Posts Tagged Canon EOS 550D

RAW vs JPEG – Usability

RAW versus JPEG. Which should I use? This is a very interesting and delicate subject involving many aspects! First of all I must say that I think that there is no doubt about the fact that a RAW file is superior – information-wise – compared to a JPEG! It is lossless, has more information per pixel (more bits/pixel), … etc. There are drawbacks also: very large files (25-30MB/picture for Canon EOS 550D), always having to postprocess…etc. There is also no doubt that you get the greatest abilities to adjust your picture with a RAW file. I have had this question for a long loong time and now is the time to finally try to get it resolved:

Is  there much to be gained from using RAW for an ordinary photographer – like myself?

Are there BIG advantages – for me? Or is it more like carrying two spare wheels for a car? Something that could be of use – but only “once in a blue moon”? Is RAW something I ought to use? Is it worth the hassle, time and space? If I pay good money for a DSLR or a premium compact am I throwing away good money by not going RAW?

I will try to stay out of the technicalities – as this post is really about usability for a normal everyday photographer – with some slight ambitions! (That is like myself! 😉 ) I want some time over for other things as well! This is not for pixel-peepers – but we will peep at pixels now and then to get at the answer! My idea for this post is to find out how close I can get with RAW and JPEG. I will be trying to get the same – or close to the same – results from post-processing both RAW and JPEG – and then comparing the result to see if it can be accepted by someone like me – an ordinary everyday photographer  – with some slight ambitions! In ordinary everyday photography with ordinary everyday camera settings will I get enough room and flexibility to handle the ordinary everyday photo situations – if I go the JPEG way?

As most photographers – especially those with compact cameras – uses JPEGs all the time the answer should be given already: JPEGs are good enough! (Or at least a good compromise.) But I want to find out how much I lose out by going JPEG – or could I actually gain something when considering more factors…?

Summer is quickly approaching here in Sweden and it’s beginning to look and feel wonderful! I am saying this so you will understand why this task might take some time before reaching an answer. While on this journey to find the answer – my answer – I would very much appreciate your input and ideas on what to look for and what to compare!

The Formats

RAW is really many different file formats – specific for most cameras or camera brands Canon, Nikon, Sony, etc … – containing more or less unprocessed info directly from the camera image sensor – and need a special program (or a plug-in to your favorite image software) for your computer to process. Software and/or plugin are usually included with the camera when you buy it. It is sort of a “digital negative” – which you then process – in your computer – into a JPEG or several with different settings. The fact that each RAW format is a manufacturer specific format does raise some (small?) concern in me about the usability over time…

JPEG or JPG files are standardized picture files (JPEG – Joint Photographic Experts Group) that can be viewed, processed and printed with all (?) image software! Not that all standards survive over time but still it is calming to know JPEG is a proper standard so (almost) any type of software with image support will open a JPEG-image – hopefully for many years to come! These JPEGs are created in-camera by the cameras image processor. The process in the camera can usually be adjusted in a few ways: White balance, Contrast, lightness, saturation, sharpness, etc … and also in more general terms like for portrait, landscape, neutral, vivid, vintage … etc.

The Variables

The are quite a few factors/variables that influence the look and quality of pictures and to even contemplate evaluating them all is quite mind-boggling! It gets even worse when trying to weigh in such things as time spent processing, flexibility, storage space, fun(!), etc.. I would have to limit myself to just a few of all the factors – but I am open to suggestions as to which! Hopefully this journey will help me to decide what really matters – at least to me!  Hope you will tag along and find your own set of what you believe are the most important factors! The following are a few of the different variables to compare: Exposure, Dynamic range, Colour saturation, White balance, Sharpness, Contrast and Noise…

The Photo Mission

I set out with my trusty Canon EOS 550D/Rebel T2i to take a bunch of pictures like any tourist (with some slight photographic ambitions) would do. I set the camera for saving both RAW and JPG. The plan was to let the camera do its automatic “magic” so I set it up for what pictures I like to get out of the camera: one notch up on contrast, saturation and sharpness! I know from comparing the different Canon picture settings that “Neutral” actually gives quite good likeness to the original – but  rather soft picture – that I would not be satisfied with but that I always would have to post process. “Standard” is my most used setting + every now and then I use “Landscape” settings. Sometimes throwing in a “Portrait” or two. I have tooled with the idea of creating a RAW to JPG processing of my own and download it to the camera. (The Canon EOS 550D/Rebel T2i allows you to do this – giving you access to loads of settings!) The more I think about it the more I wonder why I haven’t…!

The Tools

The software I will be using is Canon’s Digital Photo Professional, Adobe Photoshop Elements and IrfanView. I am also using a 24″ 1920×1200 pixel Dell UltraSharp U2410 display.

The fine print:
The above was a lot of technical stuff – don’t be scared of it because my intention is to mostly use my eyes to make up my mind and include samples so you can use your eyes and make up your mind! I will of course give you my opinions of how the pictures should look! The reason why I stress that you make up your mind is because as we all know taste and liking is not universal! You might like a different look on your pictures and because of that you will have samples to look at so that you can make up your mind! Hopefully we can all arrive at a good understanding of this tricky question!

I will update this posting to contain the complete article as I go along!

Till next time!

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Canon IXUS 210 IS – Sample Photos

Having a camera like the Canon IXUS 210 IS (also called PowerShot SD3500 IS) should – I think – place you in the category where you want good pictures without too much hassle! At least that is the assumption I have made during my testing for this review. Here I should add that this is what many many photographers want! To be able to concentrate on the motif and forget as much as possible about the technical side! Still it would go too much against my grain to use “Full auto” so I have set the camera to “Program auto” when comparing it to the Canon PowerShot S95.

Under a few common lighting conditions the two cameras will battle it out to see what kind of sample photos they will produce – on their own – with the setting “Program auto”. There are a number of differences between the cameras – and we will see how that affects the pictures! As I have pointed out earlier on these pages the differences between most cameras on low ISO-settings when lighting conditions are good (sunshine or very light clouds) are very small – even between DSLR’s and compact cameras! Ok, Ok – when pixel peeping you will see differences … But the differences are not much to write home about – not when the full picture is shown on the screen – not even when viewed on my  24″ 1920×1200 pixel screen! (As you probably know that translates only to just over 2Mpix – roughly like a FullHD television screen! On (large) printed pictures is where the differences might show – if you are very close (sort of pixel peeping again… 😉 ) BUT as the light gets weaker – even just a day with proper clouds – the differences start to show very clearly!

Note that what I will be testing is each cameras ability to produce good pictures – under similar conditions! Not what pictures you will get using the same exposure time, the same f-stop, etc..

Indoor Sample
First out will be indoors sample photos. The one not so common circumstance was to use a table for support on these pictures. Most people tends to take handheld pictures but they would have been very blurry …! Low light is not be the easiest – but quite common – task for these cameras!

As always the pictures are unchanged and unedited – this is how they came out of the cameras – only filename has been changed!

   Canon IXUS 210 on the left, S95 on the right.

Let’s start by looking a little at what settings these two cameras chose – and try to guess why the camera chose those settings!  The IXUS 210 chose 1/20 sec and S95 1/15 sec, both picked f3.5, but chose very different ISO values 800 and 80(!). It is not very easy to guess why the cameras picked so different settings for this albeit lowly lit but evenly lit subject.  Also why S95 picked f3.5 instead of f2.0 – that would have been the logical selection when light is sparse. If I would have picked settings I would have chosen to go with the full opening f2.0, 1/30 sec and let the ISO sort itself out. ISO would probably stop at around 80 – so I would probably have gotten away with slightly shorter shutter time or slightly higher f-stop. Considering the image stabilization my picking 1/30 sec is probably very conservative – for a stationary subject… But the great MYSTERY is how the cameras could have picked so very different ISO values – 800 against 80 – and that the lightness of the pictures still do not look soo much different! Agreed the IXUS 210 picture looks a little on the light side – but 800 to 80 – that is over three steps!

As can be seen the difference in chosen ISO-values makes a lot of difference when it comes to sharpness and noise in the picture. The S95 picture is clearly the winner here – even if I do not understand why the cameras picked so different ISO-values!  The IXUS has clearly overexposed this motif a bit and also the white balance is a little on the cold blue side. The differences are so big that any deeper analysis of the two pictures qualities would not contribute to anything! Of course any (at least from a compact camera) ISO 80 picture will be better than any ISO 800 picture!  Click on the pictures and see for yourself!

Even if my idea for this test aims to show the above – how the pictures from a camera will look during different but common lighting conditions – I am a little baffled by the above … so for those of you that – like me – wonder how much the IXUS and S95 differ at the same ISO-value I will include another indoor sample – this time forced to the same 800 ISO-value!

   Canon IXUS 210 on the left, S95 on the right.

Now the differences are not that big – but first let’s look at the settings the cameras picked when forced to use ISO 800. The IXUS and S95 chose 1/15 sec and 1/50 sec,  f3.5 and f2.0. Again this baffles me – a little at least! The IXUS could not do much but pick the largest aperture f3.5 and then got 1/15 sec as a result. But why did the S95 pick such a “short” shutter time 1/50 sec this time? And used the widest aperture to achieve this – when it not did so in the umbrella picture above?

Looking first at the noise levels they are somewhat similar but still it is quite clear that the S95 has much lower noise levels generally – both in dark corners and in “well-lit” areas! The saturation and contrast are slightly higher on the S95 picture – also affected by the lower noise levels. Sharpness in a ISO 800 picture is always very much affected by the rather high levels of noise but also here the S95 trumps over the IXUS.

The above is while pixel peeping (Click on the pictures and do it yourself to see what you think!) but most of it is not visible on my 24″ 1920×1200 pixel display. That is not to say that there are no differences – flipping between full size images I can both “sense” and actually see a little better saturation and slightly better sharpness in the S95 picture.

Conclusion – Indoor Pictures
The S95 has a clear edge over the IXUS 210 with sharper pictures that has better saturation and better contrast. The S95 also has lower noise with higher ISO-values.

Outdoor sample
Time for an outdoor picture taken in good light.

   
Canon IXUS 210 on the left, S95 in the middle and EOS 550D on the right – or below (depending on your screen width)

Here a slight tonal difference is clearly visible – with the IXUS going for a slightly colder colour and the S95 for a slightly warmer look. I brought along my trusty old EOS 550D for the comparison as the “gold” reference. Based on the EOS colour I would have to lean to that the S95 probably is the most correct one.  My memory of the sky colour at the time is not so exact so I could not say which is the most correct. These three pictures are similar enough that except for the tonal differences I can see no other differences when viewing full screen. This was expected – as the lighting conditions were so favorable! The settings for the pictures were – in the above order – 1/1250, 1/1000, 1/320 and f3.5, f4.5, f11 and ISO 80, 80, 100. Both compacts going for shorter shutter times – probably both because of there being fewer* F-stops to choose from and because of their intended target users … (The last is just a guess!)
(* Compacts very often has just a few f-stop settings. Some cameras go as low as two settings! Full open and something around f5.6-f8.0)

Conclusion – Outdoor Pictures
As expected – in good lighting conditions – all three cameras produce good results! Both the IXUS and the S95 faring very well when comparing them with the EOS 550D.

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Canon PowerShot S95 – Depth of Field

The distance from the closest to the most distant part of a motif that is sharp is called Depth of field (DOF). DOF affects all pictures – sometimes you want DOF to be shallow to bring out and concentrate the interest on your sharply focused main motif while the background is blurred … other times you want sharpness from close up and all the way to infinity – with a really deep DOF! This post is both a general post on DOF but it also contains specific samples that relates to the Canon PowerShot S95!

All cameras with a small sensor – and a correspondingly short focal length on the zoom lens – has a depth of field (DOF) that is quite deep! This applies also to the Canon S95 with its 6-22.5 mm zoom lens. For a DSLR with a bigger sensor it is a little more varied – but usually the DOF is more shallow.  This can be both good and bad – depending on how you want your picture to turn out!
(The picture above is taken with Canon EOS 550D 18 mm and f 11.0 – to get a deep DOF. Not shown full size.)

The DOF is affected by three things:

  • Focal length
    The shorter focal length (you might like to think of it as wider angle) the deeper DOF and (it follows) the longer focal length the narrower DOF.
  • Aperture
    The smaller the aperture (that is bigger f-value) the deeper DOF and larger the aperture  the narrower DOF. You really need a large aperture to get a nice blur!
    One complication with most zoom lenses is that they vary the aperture as you vary the focal length!
  • Distance to the motif
    The more distant you are to the motif the deeper DOF and the closer you are the narrower DOF

All of the above factors are combined so that:
The deepest DOF you will get when you are using a very short focal length, a small aperture and are very distant to your motif!
The most shallow DOF you will get when you are using a very long focal length, a large aperture and are very close to your motif!

Depth of Field diagrams

To keep things reasonably simple I will look only at the extreme values: widest angle and most tele – with biggest and smallest aperture. Moreover I have limited it to two focus points at 1 and 6 meters.These 8 cases I have plotted in a DOF Diagram for the Canon S95 – and as a comparison I have included a DOF Diagram for the Canon EOS 550D 18-55 mm  . The two top rows are showing the tele results and the three bottom rows showing wide angle. The small black marker on top of each bar is the focus point (1 or 6 m) and you can see how the DOF spreads out around it (the green/violet bars). Note that as you goes towards smaller apertures the DOF behind the focus point increases a lot!

Canon S95 DOF diagram. Looking only at the two most extreme combinations – for deepest and most shallow DOF:
Using wide-angle, f8.0 and focusing at a close object at 1 meter we get a DOF of  0.43 m – infinity. That is close to the deepest DOF you can get with the S95! Handy for landscape pictures or whenever you want everything to be sharp! Notice also that it does not matter that much if you focus on something 6 m away instead – you will still get almost as deep DOF of 0.7 m – infinity!

If you use the largest aperture (f2.0) you will still get a relatively deep DOF at a distance but it will get more shallow at 1 m.

Using the largest aperture with tele, f4.9 and focusing at a close object at 1 meter we get a DOF of  only 0.95 – 1.06 m. That is a reasonably shallow DOF! Handy for a portrait (face only) or where you want only the main motif to be sharp! Here it does matter a lot if you focus 6 m away instead – you will get a DOF of 4.5 m – 9 m! At around 6 m this works well for a full picture of a person and a few meters more will handle a whole group of people – who does not have to stand on a line either! You will get a blurred background – but (I am sorry to say) only slightly blurred.

If you use the smallest aperture (f8.0) you will still get almost as shallow DOF at 1 m but at 6 m distance the DOF will increase a few meters! Note that the only way to accomplish a really blurry background is when you take pictures really close up … Also note that due to the fact that the aperture in the tele setting is f4.9 you will not get an extremely blurry background if your motif is a few meters distant!

Canon EOS 550D 18-55 mm DOF diagram. Also with its biggest and smallest aperture – BUT note that this lens has very different extreme values for its aperture!

Looking only at the two most extreme combinations – for deepest and most shallow DOF:
Using wide-angle, f22 and focusing at a close object at 1 meter we get a DOF of  0.43 m – infinity. (Same DOF as the S95 but with a very different aperture!)  Again that is close to the deepest DOF you can get with the wide-angle!

If you use the largest aperture (f3.5) you will still get a relatively deep DOF at a distance but it will get more shallow at 1 m.

Using the largest aperture with tele, f5.6 and focusing at a close object at 1 meter we get a DOF of  only 0.97 – 1.03 m. That is a very shallow DOF! To be used where you want only the (small)  main motif to be sharp! If you focus 6 m away instead – you will get a DOF of 5 m – 8 m!

Here it is a little easier to accomplish a really blurry background when you take pictures really close up … But note that 55 mm is not long enough to give a really blurry background at a distance! You will need 100-200 mm lens to accomplish this on a half-size sensor camera like the Canon EOS 550/Canon Digital Rebel T2i!

I have already said this (in the 3 points above) but want to stress that – for all lenses – as you move away from your motif the DOF increases (can be seen very clearly in the diagrams) giving you less and less blurry background. If you focus at 18 m you will with the S95 at the longest focal length and largest aperture (f4.9) have a DOF stretching from 9 m to infinity – not much hope for a blurry background there – but on the other hand you will get a picture where most of it is in focus – could also be handy sometimes…

Want to dive deeper into the shallow depth of DOF? 😉 Then go to Wikipedia for a much longer and much more detailed take on the subject with formulas, diagrams etc…

Three examples

Blurry background – Portrait or flower
You probably want a nice blurred background to make your motif stand out. Ask your motif to move away from the background (flowers – I am sorry to say – only moves when you want them to be still! 😉 ) – the further away from trees, houses etc the better! Then use your zoom at its maximum tele setting (if you have one of those super-zooms you don’t need to overdo it 🙂 ) and you step back from your motif – but only as far as is absolutely needed to get enough coverage of your motif! Make shure that the camera (or you) select as large aperture as possible!
(The picture on the left is taken with Canon EOS 550D 55 mm and f 5.6 (full open) – to get a shallow DOF. Cropped and shown half scale.)

Possible problems:
If you want blurry background when photographing a flower: On many compacts you can only use the “macro” setting with the wide-angle! Accept it (you might like it) – or try to go as close as possible with maximum tele setting – this is by far the best way to get a nice blurry background!
The whole picture turns out blurry? Then you have shaken the camera – hold it more still – get some support! Tree, rock, table or … maybe even a tripod! You can also get a totaly blurry picture if you have missed the focus completely!

Blurry background – Group of people
Assuming you want the whole group to be sharp – first of all you have to have them all at roughly the same distance! For blurry background you do the same as with the portrait or flower above: Position your group far away (at least 10-20 m) from the background! Use your largest aperture and as much tele as you can and then you walk away – but only as far away from your group as needed – until you get them all to fit in the picture (with the tele setting). The only special handling with a group is if they are not standing at exactly the same distance: focus on one of the nearest persons in the group. Assuming that the nearest and most distant person are not more than a meter or two apart you will get a sharp picture of the whole group and a somewhat blurry background. The longer tele lens you have the nearer on a “line” the group must stand – but the “blurrier” background you will have!

Sharp background – Person or group in front of Eiffel Tower
Or any other picture where you want the surroundings to be seen clearly. Here you probably want a deep DOF so that as much as possible can be seen clearly. First of all you move away from your foreground motif and use your wide-angle. To get maximum DOF you should also use the smallest possible aperture. But also take one picture with what f-value the camera suggests – it might be good enough.

Canon S95 DOF Samples

First of all I must disappoint all of you who is hoping to get a very blurry background in your portraits with the S95 – or any other small sensor short focal length lens cameras! It will not happen – even with a large aperture lens as the f 2.0 one on the S95! But as largest aperture at tele is just f4.9 you will only get a really blurry background when you use max tele in a very close up picture – that will not cover a view big enough for a proper portrait – but might work for a close-up of a flower for example. If you have a super-zoom you are luckier but will need to use the tele setting and hold the camera very very steady!

I have taken two series of pictures samples. You will see a variation of the DOF but it is so small it hardly is worth mentioning.

The first series in which I vary the focal length from 28 mm to 105 mm (equiv – in reality 6-22.5 mm ) and use the lowest possible f-value. This affects the perspective – more than it affects the DOF. The difficulty here is that the Canon lens is only f2.0  at the wide-angle end – and f4.9 at the tele end. So as I zoom to tele I also increase the f-value and thereby keep the DOF almost constant.

The second series I kept the focal length at a mid position and varied the f-value. Also very little variation of DOF!

As the DOF variation is so small I have just put up the extreme samples – but trust me – the intermediate pictures looks much the same! All pictures are taken with AWB – which handles the flourescent energy-saving lamps quite well! The hat sits 50 cm in front of the wall.

           

Looking at the above pictures you can easily see that for the Canon S95 the first picture has the most blurry background. This is due to two factors: I am closer to the motif and can use f 2.0  – this together affects the background most thus giving the most shallow DOF – even if I use the wide-angle! And a hat – contrary to a person – usually does not complain about certain features (like the brim) looking a bit wide! 😉

I will add a few extra samples with the motif further away from the background to illustrate how blurry you can get the background – as soon as the weather improves! (We have had the coldest winter for at least 150 years!)

If you want to have really seriously blurry background with an ordinary zoom compact – you have to fire up your favorite image software and get to work! Or get a super-zoom… If you on the other hand want to have a deeper DOF than you can get with your camera and lens combination – then you can combine several pictures with different focus into one picture with a lot of work in Photoshop or similar – or you cold just use CombineZP that automates the process.

Hope this throws some light on DOF for us photo amateurs!

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Canon PowerShot S95 – Sample Photos ISO Effects #2

This is the second set of sample pictures from the Canon PowerShot S95 and Canon EOS 550D (or Digital Rebel T2i). The main goal is to see how different ISO settings – from low to high – affects the picture quality – mainly the noise levels but also colour saturation. Because this second set is looking – image quality wise – so similar to the first set I will refer you to the first set for comments!

The “Midnight sample” to the left is an extra sample I included. Taken close to midnight with only street lamps to light the scene. The light was very yellow so I used custom white balance. ISO 1600, 1/20 sec f 2.0. Turned out alright I think! For a mysterious effect look at the dark sky on the right and you will see a strange pattern – it can also be seen if you look at the sky between the tree branches! I think it is a combination of noise and the structure of the very dark clouds that was at the time when I took this picture.

Canon S95 Samples – ISO 100 and 200

 

Canon S95 Samples – ISO 400 and 800

 

Canon S95 Samples – ISO 1600 and 3200

 

PhotomanCompareStrip – Canon PowerShot S95

Canon EOS 550D Samples – ISO 100 and 200

 

Canon EOS 550D Samples – ISO 400 and 800

 

Canon EOS 550D Samples – ISO 1600 and 3200

 

PhotomanCompareStrip – Canon EOS 550D

Hope you had some use of this second set!

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Canon PowerShot S95 – Sample Photos ISO Effects

In this post I will be showing samples from the Canon PowerShot S95 and the Canon EOS 550D (or Canon Digital Rebel T2i). This time the main goal is to see how different ISO settings – from low to high – affects the picture quality – mainly the noise levels but also colour saturation.

As  always all of these samples are full size and have not been edited in any way – except changing the filenames! I have taken a series of pictures of the same motif with the two different cameras: Canon PowerShot S95 and Canon EOS 550D (with the kit lens EF-S 18-55 mm IS) – mostly as comparison – but they are interesting on their own as sample pictures from the 550D! I know it is VERY unfair comparison because of sensor size, price … etc but at least there is something that can be used as a sort of “gold” reference. A compact would have to work VERY hard to surpass any decent DSLR as the ISO goes up – and the light goes down! Give me sun (or rather low ISO) and the pictures are very good from all cameras!

NOTE! I forgot to reset the contrast and saturation on the 550D to factory setting – so the pictures can not be directly compared between these two cameras! I will redo this as soon as I have a chance! Sorry for this!

 As I like to see how the cameras work under real world situations (and I am also quite lazy 😉 )I let the respective cameras handle most settings automatically – only intervening at special situations or at price winning photo opportunities!

Both cameras were set similarly: Programmed Automatic Setting (P), AWB, all other settings to normal. Note that the sharpening on 550D is normally set for “soft” from Canon – I did not change that!

The Samples
I will of course put up the full-size samples – but I will also put up what I call “PhotomanCompareStrip” – where I have taken the same (what I think is) representative area of the picture for each of the different ISO values. This way you can very quickly see how higher ISOs affect the picture quality. I have saved the “PhotomanCompareStrip” as PNG-files so the picture quality in the crops will not be affected by one more destructive JPG-compression! Be sure to click them to see the crops in 100% size! Well, you will see below what it is – I hope you will find them convenient ! 🙂 For a more detailed look I do recommend the full size samples!

For the following I think it best to explain what I mean by “pixel-by-pixel” and “full screen”. Firstly “pixel-by-pixel” is when you size the viewing of the picture on the screen so that each pixel in the picture will be show as one pixel on the screen. This means that you can only see a (small) part of the picture but can scroll around to see other parts of the picture. Secondly “full screen” is when you scale (down) the picture so that you can see the full picture on the screen at once.

Canon S95 Samples – ISO 100 and 200

 

Both ISO 100 and 200 are quite good with the S95  I think. No disturbing noise and hardly any loss of detail! definitely nothing that can disturb your eyes if you look att the picture full screen on any normal computer!

Canon S95 Samples – ISO 400 and 800

 

ISO 400 is still quite good – but with some minimal loss of detail that you only can see on a pixel-by-pixel view! At full screen viewing some loss of contrast creeps in. Again you can not see any flaws in sharpness if you look att the picture full screen! The same can not really be said about the noise – which if you look very carefully at evenly lit areas – the sky for example – can be seen or at least “felt” even at full screen – and definitely at pixel-by-pixel viewing! It is not very disturbing – if at all seen in full screen!  ISO 400 is not att all bad and I would say that it is good enough for most purposes!

ISO 800 is still good enough – especially for full screen viewing. You can see differences between ISO 100 and ISO 800 but the later it is definitely still good enough to be used in most situations – even if big size printing will show some noise! Looking att ISO 800 on pixel-by-pixel shows that it is here that the image quality starts to be affected more clearly. Noise, sharpness and contrast are all affected.

Canon S95 Samples – ISO 2000 and 3200

 

ISO 2000 is really an amazing sensitivity – but you pay for it in noise, sharpness and contrast which all are affected. It is still quite alright to view full screen – but now you can quite easily see the noise in the sky and less detail and less contrast in the tree branches at the and of the street. Looking at it pixel-by-pixel you see a significant drop in image quality even compared to ISO 800! Most details have been lost and it has to be said that ISO 2000 should only be used if you really have to to get a picture! Still alright for big objects that fill a bigger part of the picture – but do not at all expect that razor sharpness! Compare it to the Canon EOS 550D picture below for ISO 1600 and you will realize that even if the S95 has a much developed new sensor it is no match for a bigger sensor – but the S95 sensor and processing certainly stands well up against other compact cameras. Compared to my previous “new sensor compact” Samsung WB2000 the S95 has more colour saturation as standard!

ISO 3200 is actually not much worse than ISO 2000 – so much of the same comments apply here! There is some more loss of detail but the big step seems to be between ISO 800 and 2000!

One thing to note: The ISO 3200 sample is slightly over exposed! The camera indicated this – as its aperture does not go any smaller the f 8.0 and the shutter time not any shorter than 1/1600 sec there was too much light for it to handle at such high ISO value.

PhotomanCompareStrip – Canon PowerShot S95

As I have given most comments on the full size samples I will here only observe that you can very easily see the first big drop in resolution when you step up to ISO 800. This is very good – as you normally will not have to go any higher than ISO 400 in outdoors daylight photography. Indoors, restaurant, candle light you might be more willing to accept a little more noise and softer pictures… You can also use the S95 flash – which I seem to love to hate – its annoying but good – if you accept the flat light from a built-in flash. Even if contrast and saturation is affected by the increase in sensitivity there is a very good general similarity between the pictures taken with different ISOs.

Canon EOS 550D Samples – ISO 100 and 200

As this review is of the Canon PowerShot S95 I will not comment the Canon EOS 550D samples.

 

Canon EOS 550D Samples – ISO 400 and 800

 

Canon EOS 550D Samples – ISO 1600 and 3200

 

PhotomanCompareStrip – Canon EOS 550D

A few general comments on the Canon EOS 550D samples. The image quality is amazing with perfectly acceptable results up to ISO 1600 – with very litte loss of detail or colour saturation and very well controlled noise. At ISO 3200 there is an increase in noise and a certain loss of detail but it is still quite enjoyable – especially full screen where you will see almost no loss in image quality. Looking at the picture pixel-by-pixel it looks softer than at lower ISOs and the noise is higher but still well controlled and not very disturbing – especially considering it is a 18 Mpix picture you are looking at!

More in part #2 of Canon S95 samples! 🙂

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Canon PowerShot S95 – Sample Photos

At last I have managed to get the sample photos from the Canon PowerShot S95! The post might as well be titled “Canon EOS 550D – Sample Pictures” (or Canon Digital Rebel T2i) as I will be including – as usual – sample pictures from the 550D – of the same motifs taken at the same time. The cold and snowy weather has – for some time now – kept me from getting comparable pictures from both cameras! The motifs are – of course – much of snow so I plan to do more samples of less snowy things when I get an oportunity!

As  always all of these samples are full size and have not been edited in any way – except changing the filenames! I have taken a series of pictures of the same motif with the two different cameras: Canon PowerShot S95 and Canon EOS 550D (with the kit lens EF-S 18-55 mm IS) – mostly as comparison – but they are interesting on their own as sample pictures from the 550D! I know it is VERY unfair comparison because of sensor size, price … etc but at least there is something that can be used as a sort of “gold” reference. A compact would have to work VERY hard to surpass any decent DSLR as the ISO goes up – and the light goes down! Give me sun (or rather low ISO) and the pictures are very good from all cameras!

The test shots were taken shortly after midday – with hardly any clouds and no visible variation in lighting. Bear in mind though that the sun does not rise very high on the sky here in Sweden at this time of year – giving a sort of afternoon warmth to the light and very much shadow areas!

Both cameras was set similarly: AWB, all other settings to normal. Note that the sharpening on 550D is normally set for “soft” from Canon – I did not change that!

PRESS STOP! I just saw that I had forgotten to reset the contrast and saturation on the 550D to factory setting – so the pictures can not be directly compared between these two cameras! I will redo this as soon as I have a chance! Sorry for this!

Comparing camera pictures is SOO difficult – all cameras should really be set so that YOU think it gives the best possible result – not just left with what the maker thought was the best… well... Hands up all those that have left the setting at what it was out of the box!  Taking into account that both cameras has different resolution is soo tricky – you will have to scale either way and then the sharpness changes…. but it does all the time that you look att pictures on a screen – very few 18 or 10 MPixel screens exist! Printing the pictures on paper and then comparing them is, I guess, the most fair method…

I will be showing sample photos aimed at different goals. First is the wide-angle and tele sharpness samples – with some 100% crops to make comparison easy!. Then – in the next post – the increasing ISO samples – all the way from low to high ISO. These will all be full-size samples from both the S95 and the 550D.

Click on the sample pictures to see them in full size!

Wide angle sharpness samples

 

Starting with the wide-angle samples above (28 mm equivalent) both cameras produce very similar results. Taken in mostly shade with some sunlight on the roofs. Both cameras were set for ISO 100 and the Programme Setting (P). The S95 picked 1/320 sec and f 4.0 – the 550D picked 1/125 sec and f 7.1. Both combinations are ok – the s95 goes from f 2.0 to 8.0 and the 550D from f 3.5 to 22 so I guess it makes some sense in the S95 staying with the larger apertures. Having the widest angle – that is lessening the effect of visible camera shake and image stabilization still does make me wonder why the S95 picked such a short time and such a large aperture? Would it not make sense to increase the depth of field by using a smaller aperture? The visual impression is of  two cameras that produce similar good sharpness – even if the resolution differ quite a lot! Quite impressive!

This is something to note – that some compact cameras will give images of a quality close to that of a DSLRif used with low ISOs and in good lighting! Once again: Quite impressive! That leaves us with the tricky question of lenses – and there is no question about it – the lens do influence the result! The 18-55 mm Canon kit lens is quite alright – for its price – but better lenses do exist – for a price! I have one prime lens – EF 50 mm 1:1.8 II – that is regarded as very good lens – for its very low price! Build is plasticy – but sharpness when stopped down a little is quite good! I will try to include samples of this when I redo the samples!

From the samples above I have cropped an area of the top of the tree in the middle. On the left I have shown these two 100% crops – different in size due to that the cameras have different resolution – 10 Mpix and 18Mpix.

In between them I have also included a 550D scaled crop (70%) to make it the same size as the S95. I scaled it with Irfanview to show what happens with a picture when you scale it down. As you can see the sharpness goes up! In real life you would (for viewing on a computer screen) scale most images much more than  this – increasing the percieved sharpness – and at the same time loosing some detail…! The maximum resolution and sharpness would only be of use when you print out or crop your picture! This is of course good news to anyone mostly viewing their pictures on screen – any camera (almost) will look real good! 🙂

There are many other interesting parts to look at in the sample pictures! Look at the green bin in the shady area by the fence at the left. There you can see slight noise appearing in the S95 picture where as the 550D is almost noise free.

Also on the tree branches in the very top right you can see that the sharpness has gone down a bit and also some slight purple fringning can be seen. This is something that I can not see when I scale the pictures to fit my screen!

Tele sharpness samples

 

At the tele samples above (85 mm equivalent) both cameras again produce very similar results. Taken in mostly shade with some sunlight on the roofs. Both cameras were set for ISO 100 and the Programme Setting (P). The S95 picked 1/200 sec and f 4.5 – the 550D again picked 1/125 sec and f 7.1. Both combinations are ok – but as the cameras both are using a longer focal length shutter times should really be shorter not longer as with the S95 – the f 4.5 is because at 85 mm that is the aperture you get with the S95 lens. This really comes back to the wide angle – why the S95 picked such a very short time for that? Anyhow, again the visual impression is of  two cameras that produce similar good sharpness! Quite impressive!

 

In the crops above you can see that in the tele setting again the sharpness  is quite similar – both in the centre crops (first) and in the corner crops (second)! One has to be a little amazed at the resolution of the little lens of the Canon S95 has to produce on its very small sensor with its extremely small pixels to look as good as the ones from the Canon 550D with its much bigger sensor! It is 43 mm² compared to 329 mm² which – when the Mpixels are taken into account makes the S95 lens over 4 times as sharp! A bigger sensor actually puts less requirements on the sharpness of the lenses!

Till next time – happy snapping!

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Panorama pictures

This post is about how you take and make panorama pictures or panoramic pictures with just a camera and software! I have been using Canon EOS 550D and Canon PowerShot S95 and Canon Ixus 860IS to illustrate how you go about it with a DSLR and a Point&Shoot but you could be using any camera! What’s more – it is quite easy! 🙂

The short story:  1  Take a number of overlapping pictures   2 Join (stitch) the panorama together using software!

The panorama picture above I took in Chania harbour in Crete, Greece. It took just a few seconds too shoot and resulted in a picture of close to 20 Mpixels. In this I actually used my first Canon Ixus 750 with 7 Mpixel resolution and that had a stitch assist mode. (Read here about what stitch assist mode is.)

If you look at the first row above – where all the separate pictures are shown – you will see that there is an overlap between each neighbouring picture of around 30%. That is: the same part of your motif appears in two neighbouring pictures! (See the illustration on the left – the grayed areas of the motif are the same in both neighbouring pictures!)  The amount of overlap is not critical – but if you have too little overlap the software that you use to stitch the pictures together might have problems finding common points! If you have too much overlap that just forces you take more pictures to get the coverage you want – that is ineffective but will probably not hurt! At the same time you will get more pictures that has to be stitched ==> giving more joins that might be seen! So my advice is try to keep the overlap at 30% (optimal) and not higher than 50%! Use the zoom to decide the how much of the motif you want to have height wise and let the number of pictures decide how much width you want.

To achieve this overlap take the first picture and then rotate the camera (in the Chania example above) to the right – but make sure to keep part of the first picture in the second one as well! Then you just repeat this over and over again till you have covered as much as you want. Maybe you are satisfied with just two pictures – or you might want to go the full 360 °.

In the illustration on the left you can see this! See the overlap of the pictures as three bars in the top of the illustration.  Take the first picture (green 1) then rotate the camera (according to the green arrow) – but only so much that you still have about 30% left of the 1:st picture. Take the next picture (lilac 2) then rotate the camera again – keeping 30% of the previous picture .  Take the next picture (orange 3). Repeat this for as long as you want!

Sweep Panorama
A lot of cameras this season has something called “Sweep Panorama” or something similar – in which you just press the shutter button, slowly sweep the camera sideways, release the button and then it automatically creates the panorama picture. As convenient and quick as this might be – and fun to see on the small 3″ display – as sad you will be at home on your 24″ computer screen – when you realize that what you got it is just a low resolution panorama! I don’t want to kill anyones joy about the “Sweep Panorama” – it certainly has its uses and it is fun! It is just that it is a low resolution panorama – but sometimes that is enough! This post is about creating – with minimal extra effort – beautiful high-resolution panoramas using any camera and separate software!


Also remember that taking panorama pictures does not have to be a wide&low or a high&narrow picture! You can take a matrix, say 2 rows of 3 pictures, to get a better resolution or just to get a wider picture in a cramped space  – where your widest angle lens or widest setting is not enough! I use it indoors quite a lot to fit the whole room in! (See sample above! And in case someone is worried about my reckless driving – taking a panorama picture on the go – I can calm you with that I had actually parked the car! 😉 )

Now the preamble is over – let’s  go on to the two easy steps to panorama pictures! YES! 🙂

For all three alternatives below – if you have an evenly lit motif – you can of course skip the steps concerning locking exposure to the most typically lit part of your motif and just start the sequence of at the first picture!

1. On location you do this

Five steps to beautiful panorama pictures using a
Point&shoot camera with stitch support:

  1. Select your panorama mode – on the Canon S95 it is called Stitch Assist and can be found as one of the scene modes.
  2. Look at your motif and decide which part of it is most typical – lighting wise.
  3. Halfpress the shutter button to lock exposure and white balance on that typical part of the motif.
  4. Reposition the camera to the most left or right part of your motif – and take picture no 1.
  5. Take the following pictures – making sure to line up the pictures according to the Stitch Assist.
  6. You are ready – on location!

Three steps to beautiful panorama pictures using a
Point&shoot camera without stitch support
 

  1. Assuming the motif is relatively evenly lit!
  2. Take picture no 1.
  3. Take the following pictures – making sure to overlap 30-40% with the previous picture.
    Also try to align the pictures vertically as best as you can.
  4. You are ready – on location!

If your camera has the ability to lock the exposure and the white balance you should do that to the most typical part of your motif. Actually you could follow the four step description below!

Four steps to beautiful panorama pictures using a
DSLR camera:
 

  1. Look at your motif and decide which part of it is most typical – lighting wise.
  2. Lock exposure and white balance on that typical part of the motif – and keep pushing the lock exposure button for all pictures! On the Canon EOS 550D it is the button marked with a “*“.
  3. Reposition the camera to the most left or right part of your motif – and take picture no 1.
  4. Take the following pictures – making sure to overlap 30-40% with the previous picture.
    Also try to align the pictures vertically as best as you can!
  5. You are ready – on location!

When I use my DSLR for panorama shots I usually do around 50% overlap – just because I find it is easier! Whatever is at the mid focus point I will move to the edge of the view finder and take the next picture – thus making it around 50% overlap. It would be even better to use the second focus points (the ones to the side of the middle) to give around 30% overlap. But as I said I find it easier to use the middle one – and the cost is just a few more pictures…!

Does the lens matter?
One question that I have got is if it matters what lens you have? Well, it affects the result but all lenses, wide-angle or normal or tele, can be used to take panorama pictures! With a wide-angle you can of course cover the same panorama area with fewer shots – but usually a wide-angle lens will not give as good result as a normal or tele lens because of straight lines being curved and vignetting (see below). The fact that you can use any lens, wide-angle or tele, means that you can use this to your advantage. With a wide-angle lens you will, as I just said, cover a bigger area with fewer pictures – to cover the same area in a tele setting you will have to take more pictures to cover the same area – probably layed out in a matrix – as I have shown in the illustration on the left. This also means MORE pixels and a sharper picture! This is actually how the Giga-pixel pictures are made! Remember to overlap!

Many zoom lenses will give a vignetting effect (darker corners) in its widest setting – this might be seen when you stitch the separate pictures together to a panorama picture. This is especially easy to spot in even same coloured areas like the sky but more difficult in uneven areas like trees or grass. (See sample at the left.) Do test this to see if your lens/camera suffers from this – you might think it is allright! If you find it disturbing you can avouid or lessen the vignetting by zooming in just a little, say from 28 mm to 35 mm (equiv). You can also increase the overlap a little so that you will not have to use the (darker) edges of the pictures. Some cameras even corrects this vignetting in-camera for many lenses.

2. On computer you do this

No matter which one of the three alternate ways above that you used you should now have at least 2 overlapping pictures! But you can have many more than 2 – you can have many hundred pictures!

You will need to join together these pictures using a special software! This is often called “stitching”. You probably got this type of software on the CD with your camera but there is also many other alternatives – both free and commercial. I was recommended the free Microsoft ICE software about a year ago – and it was so good that I have not used the software that Canon shipped with the cameras since then! 🙂  I will describe the joining/stitching process using Microsoft ICE.

The general process is soo simple! Just drop the pictures on the Microsoft ICE window – and the software will do the rest! The software will figure out how the pictures relate to each other – both sideways and up-downways (is it called that?). It will also figure out the camera motion – how the pictures were taken – if you were moving or turning the camera.

If you just have a few (2-5 pictures) the software will be ready in just a few seconds – presenting a joined together picture as the one above. The above one consists of 3 pictures. I will here assume that you are pleased with the result and want to save it as a JPG image of the largest possible size.

  • Zero – drop 2 or more pictures on ICE. It will automatically sort out how the pictures are related and join them up. (This you have just done!)
  • First you will have to get rid of the uneven edges – press “Automatic Crop” and a white rectangle will frame the picture just inside any uneven edges!
  • Second you will have to decide JPG quality. For now I recommend you let it stay at 80.
  • Third you will have to decide what size/scale you want the saved picture to have. I recommend to go with 100% – which means that all of your pixels will be used.
  • Fourth you press “Export…” and decide what name your panorama picture should have.
  • Ready! Open it with your favorite viewing software … IrfanView is a good one… 😉

The challenges

Generally the process is as simple as the one I described above – and the result is stunning! There are actually a few things to be aware of that can lessen the success of your panorama picture. Do read through the tricky points below so you are aware of them but do not let them worry you too much! Most of all: Do not let the it stop you from taking panorama pictures! 🙂

Bad alignment
This affects the picture in three ways: If you have bad alignment vertically the resulting panorama picture will be low – meaning that a lot of the top and bottom of the pictures will have to be cropped away to get even edges! If you do not have enough overlap – around 30% minimum – the software might have difficulty in joining together the pictures. If you have too much overlap – you will have to take many more pictures to get the coverage you wish. If you do not hold the camera horizontal or the resulting image might be crooked! (Thankfully, this can be corrected in ICE – see below!) Most of the time the software will succeed and you will get your panorama but it will be a little limited.

Moving objects
The Chania picture above has one very typical challenge when you take panoramas with water – waves! Any moving parts of the motif will be a challenge! It might be waves, trees, people, cars, … etc. (See sample below in the “Software Section!”) You can accept the flaw in the picture or you can maybe try again with better success … or you can use your favorite image editor to fix the picture. Waves are a real challenge! Wait for the waves to look similar at each picture you take. You will probably have to fix the resulting flaws in your favorite image editor. This is also true for the few/small flaws that you might see from the software join. One fun tip is to actually let a person appear several times in the resulting panorama picture – just ask the person to move into (preferably the middle of) each picture as you take it!

Differently exposed pictures
Microsoft ICE even out the differently exposed pictures before joining them together. It can do a lot but it is best that you try to keep the exposure similar. It is very easy with a compact camera with Stich Assist support – like the Canon S95 – because it will lock exposure when the first picture is taken. If you have DSLR like the Canon 550D it is also easy – just press the exposure lock button! Using a compact without stitch support and without exposure lock you have two alternatives: just take the pictures and let the software sort it out as well as it can – or lock exposure at the same point and reposition the camera for the first picture, lock exposure at the same point again and reposition for the second etc picture – this is OK for 2-3-4 pictures but becomes more and more tedious – but it is doable! (I would only do the second if I have a truly stunning view!)

Under this heading I have also put vignetting (dark corners) of pictures. Most lenses will show some vignetting at their widest angle – this can show up on the panorama picture as a darker band where one picture is joined with the next. Most of the time this effect is so small that you wont have to worry about it! In Canon EOS 550D this is even corrected for in-camera so you do not have to worry about it! MIcrosoft ICE handles some of this effect also. Most compact cameras do not do this – so in order to avoid vignetting – if your camera/lens is much affected – you can minimize the vignetting by zooming in just a little.

More functions

 We are now almost into advanced usage so I will not go through it fully but just mention that you can usually fix slanting or curved/crooked pictures and you can correct or even exaggerate the perspective by clicking the little 3D cube  on the toolbar! Move the mouse around over the gridlines and you will see several different alternatives to move and rotate the picture – click around and try things out!

Software

I thought I would mention something about the panorama/stitch software program that you can use to actually make the panorama picture itself. There are many different programs on the “market” both free and commercial ones. As always it is the requirements that will steer you to the right software for you! I want a software that will do most of the job automatically – with an advanced approach – and with a really good result! Preferably it would also allow me to make adjustments manually if I found it necessary! And it should also be free! I have above written about a few of the “challenges” to good panoramas. The program should – as much as possible – handle these “challenges”. It should leave as invisible joins as possible – giving me very little post processing to do! I have tried a few different programmes and they all have their strengths and their weaknesses

I have found only one – so far – that I think fills most of my requirements – Microsoft ICE – even if I would liked it to have more manual possibilities – to “help” it when it is faced with a difficult set of pictures! Many programmes are commercial and of those I have only used the ones that are included with Canon (PhotoStitch – an older version also as a free download) and Nikon (ArcSoft – a few years ago) cameras. Other programmes that are free have often very complex ways of using them – but at the same time some are often extremely flexible and adaptable – a good choice if you want to/need to tinker around manually a bit!

Just to mention a few of the other ones I have tried: Hugin Panorama Photo Stitcher (amazingly good – if you need the flexibility and have the time to learn) , AutoStitch (automatic – a limited demo available) and Photoshop Elements (surprisingly basic in its approach). To be honest I have seen that developments have been made on several of these to simplify things so there might be a new contender for my liking but …

For over a year now I have not tried any other than Microsoft ICE software because – I simply have not seen the need! Also it handles the panorama “challenges” very well. I especially like its ability to really stitch the pictures together – not just blend them along a straight line – and to even out exposure and white balance between the pictures! The only drawback I have seen so far is that ICE only allows some limited manual control over the panorama creation – especially frustrating if it can not automatically join the pictures – and I know that I could help it along manually! Remember that no software is perfect all the time! In the few cases when ICE fails I usually use PhotoStitch – because it allows me to manually set the common control points – to at least get a panorama – even if the quality is not as high as with ICE. But I can not help even PhotoStitch by specifying where it should do the blending!

   

See the samples above from a busy street in Sacre Coeur, Paris on how Canon PhotoStitch and Microsoft ICE handles the tricky moving people challenge! Notice the half seen blended man in the middle of the PhotoStitch sample (the one on the left) – not so good! ICE (the one on the right) have put the stitching in somewhere else … but where? Taking into account that this is a really busy street with lots of moving people – the ICE result is perfect!

Print the best out at a good photo lab – panorama pictures are really on their own when printed out i big size!
Good luck with your panoramas!

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