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Old Oct 16, 2009, 1:41 AM   #1
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Default Canon SX10 IS and SX20 IS Review

Steve,... I've been using your reviews of everything for years. I own a Canon S3 IS, G7, and the XSi. I just went through your reviews of the SX10 and the SX20 Cameras. If you take a close look of the sample images you included of your wife and child, for both cameras, the SX10 is considerably sharper image. Why is this? The both have the lens and they both use the DIGIT 4 chip. It this loss of image sharpness just in the difference in jpg capture, or processing settings, or is it because of the increase in Megapixels going from 10 to 12 but still using the same sensor size.?????

No one wants to get up that much image quality just to get 2 more Megapixels. What is the problem.

Thanks in advance.
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Old Oct 16, 2009, 9:15 AM   #2
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trigger,

The difference is, the SX20's sample image was taken with the ISO set to Auto, and the camera chose a higher ISO 400 setting. That photo was taken outdoors, just before nightfall, so it was quite dark outside. I caught my Wife and Daughter looking up at a bird in the trees, and I was more than 8 feet away. So, I suspect the reason it's not quite as sharp is due to the slight loss of detail from in-camera noise reduction processing.

When I took the SX10's portrait example, I had the sensitivity manually set to ISO 80, shooting indoors from about 6 feet away. If both images were taken under the same conditions/settings, I think you would see very similar quality results; the SX20 would simply produce a larger image due to having more resolution.

I hope this helps!

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Old Oct 16, 2009, 11:22 AM   #3
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Default SX10 and SX20 IS Review

billy,...thank you for the information. Where can if find the EXIF data when I look at the Samples. Other sites have complained about the SX20 being very grainy at ISO 400,... but when I look again, it seems to not to be a ISO problem but either bad DOF or just the sensor.

I just went back and looked at all of the Samples of the Canon XSi,... and now I'm beginning to see the same problem with those samples as I have been getting with my XSi that I have complained about for a year. They all are not as sharp as the image you took with the SX10. None of the 'N' pictures is sharp. However if you look at all the pictures of the XSi of the penguin, they are not sharp but it is because of DOF and bad focus. Look at the fabric the animals are sitting on. Parts of it are very sharp and you can see where the DOF and focus fall off. This is what 'Dulls' the image so I say it is not sharp. I must be spoiled by my G7 because that camera has much better control over DOF because they come out sharp. I wish I knew exactly why and maybe I could take a good picture or 2 with my XSi.

Also, look at the samples of the XSi and the shot of the birds with the 55-250 mm IS lens. There should have NEVER been any kind of problem with DOF in this shot,...but there is. The first bird is sharp and the twigs just below are also sharp but the 2nd bird is out of DOF range and has just lost sharpness. I would assume on a bright sunny day this would have been shot at f11 or higher, which should have given a better DOF. How do I look at the data to see what the shooting conditions were.

The shot you took of your wife and child looking up at the bird is also just a little out of focus. As I look close it does not seem to be a ISO graim problem, as the very tip of your childs nose appears to be sharp, but your wife's face is not as sharp,... so again, it appears to be poor focus and DOF problem. I don't know,.. I'm just guessing. Now I can see so many similarities between these images and what I am getting. This is why I sent back the camera and the lenses to Canon. Every thing I shot did not appear sharp at 100%, no matter what the DOF was. I compained that it was "Front Focus" problem and as I look at all the XSi samples, I see the same thing. Canon sent everything back and said it was all within spec.

I never get this kind of focus or DOF problem on my G7. So what do you think the real answer is.

Last edited by trigger1937; Oct 16, 2009 at 11:31 AM. Reason: spelling & added last comments.
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Old Oct 16, 2009, 11:56 AM   #4
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Many image editors can see EXIF information, including the free Irfanview. If you want to view EXIF information from within Firefox by right clicking on an image (and make sure you're looking at the full size samples versus thumbnails to see the EXIF), you may want to install the free Exif Viewer by Alan Raskin. It's cross platform (it works with Firefox under Linux, Windows or OS X).

Another popular EXIF viewer for Windows is Opanda IExif. If you want to use it from within Firefox, you'll need to install the main program from Windows Explorer and Internet Explorer first, then install the Firefox Exif viewer.

As for Depth of Field with your XSi, there is a reason it's shallower.

You have more Depth of Field with a non-dSLR digital camera because the actual focal length of the lens can be much shorter for the same framing at a given shooting distance. The larger the sensor or film size, the narrower your angle of view for a given focal length lens. The smaller your sensor or film size, the wider your angle of view for a given focal length lens.

As a result of a very tiny sensor compared to 35mm film (or as compared to the APS-C size sensor used in your XSi), the lenses on most digicams have much shorter focal lengths to get the same angle of view you'd have using a longer focal length lens on a 35mm camera.

If you look at the front of the lens on most cameras, you can usually see the actual focal lengths (along with it's aperture ratings for the wide angle and full telephoto zoom positions). With non-dSLR models like you're mentioning, your subject occupies a much larger percentage of the frame at any given actual focal length and subject distance, compared to a 35mm camera or your XSi.

For any given 35mm Equivalent Focal Length and aperture setting, you'll have a lot more Depth of Field with models like the Canon S3 IS, G7, SX10 and SX20 models, as compared to cameras with much larger sensors like your XSi. Depth of Field calculations use the actual versus 35mm equivalent focal length, focus distance,and aperture.

But, more depth of field is not always better.

Your ability to blur the background for any given aperture depends on your subject size, the percentage of the frame you need it to occupy (which you can use focal length or the distance to your subject to change), and the distance to the background that you want your subject to stand out from.

As a result, if you want a shallower depth of field, it can be very tough to achieve the desired result for larger subjects (i.e., your people photos) using a non-dSLR camera model, because it can be far more difficult to get a shallow enough depth of field to help your subjects stand out from distracting backgrounds (due to the very short actual focal lengths being used for a given subject framing at a given focus distance).

If you load this Depth of Field Calculator and select a camera model, then plug in the *actual* focal length of the lens, focus distance and aperture, you can calculate Depth of Field.

http://www.dofmaster.com/dofjs.html

Of course, keep in mind that when you use more optical zoom, you'll need to be further away from your subject for it to occupy the same percentage of the frame (hence, canceling out the benefits of longer focal lengths in some shooting conditions where you'd want less Depth of Field). But, shooting from further away with longer focal lengths can help with perspective (you'll have a more compressed background from shooting further away, which can give the illusion of a shallower depth of field).

For many scenarios (especially with larger subjects), unless you can budget for a dSLR model (which have much larger sensors compared to non-dSLR digital cameras), your best bet is to try and use software to simulate a shallow depth of field.

Shooting smaller subjects from close distances is one thing. Trying to blur the background with larger subjects is something else entirely (since you need to be further away for a given focal length to fit a larger subject in the frame, increasing depth of field).

That's one of the appeals of a dSLR (the ability to control Depth of Field to help your subjects stand out from distracting backgrounds). The sensors are just too small for that in non-dSLR models (unless you're shooting smaller subjects or zoomed in with much tighter framing, going for head shots versus full length shots).

A non-DSLR model with much greater depth of field can be a good thing, too.

You may want more depth of field versus less, and with a dSLR model, you'd need to stop down the aperture more (smaller apertures represented by higher f/stop numbers) to get it, often requiring much higher ISO speeds or slower shutter speeds to achieve what you can get with a non-dSLR model shooting at wide open apertures.

There are pros and cons to both types of systems.
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Old Oct 16, 2009, 12:22 PM   #5
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Shorter Answer:

You're going to have a shallower depth of field for a given subject framing and aperture with your XSi compared to non-dSLR models you're accustomed to using. It's supposed to work that way when you're using a camera model with a larger sensor or film size (which gives you more ability to help your subjects stand out from distracting backgrounds).

When shooting in conditions when you want more control of depth of field, I'd make sure to set your camera so that you and not the camera are selecting the focus point. That way, you can decide on what part of the image you want to be your focus point. Then, use Aperture settings to control how much of the image you want to be in focus (keeping an eye on your shutter speeds, increasing ISO speed if needed to prevent blur from subject movement or camera shake, as higher f/stop numbers for more depth of field will result in slower shutter speeds for a given lighting and ISO speed).

In other words, you'll need to become more accustomed to using a dSLR model for best results. Then, you can better understand and control your depth of field (and you may appreciate the ability to more easily help your subjects stand out from distracting backgrounds with a dSLR, when you have a better understanding of the differences with it as compared to the other digital cameras you've used).
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Old Oct 18, 2009, 1:16 PM   #6
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Default Canon SX10 or SX20

billy,.. If you actually did all the reviews of the SX10 & the SX20, did you also do the review of the XSi. In all of these review, the claim is that they were all shot in RAW and processed in an identical manner.

The difference I see in both of the pictures you took can not be blamed on ISO setting. ISO will produce a GRAIN effect as in NOISE. My point is there is NO PICTURE in the SX20 samples that when viewed at 100% shows real sharpness. If you know where there is such a picture please tell me where I can view it. I have taken 1 years worth of shots with my XSi and I still have the same problem. One other contributor to this web site, Sarah Jones, believes it is because of using the same sensor size (APS-C) and going form the Canon 350 (8Megapixel) to the 450 (12Megapixel), there is a loss of image sharpness. This is the ONLY thing that is different between the SX10 and the SX20, since they both use the exact same lens and the same Digit 4 processor, and the same APS-C sensor.

I believe the same effect is what degrades the sharpness of images from the Canon 350 to the 450, again the only change in these two cameras was the Megapixels.

If there is a better area on this web site to post this kind of discussion please let me know so we can get more confirmation.

While I acknowledge all of the information posted about DOF, I do not believe it has been a factor in the sharpness issue. I have purposely taken 10 shots with my XSi at several differen MM settings, and forced the f stop from 5.6 to f16,.. and still I can not get picture as sharp as the SX10 you took of your wife. I have downloaded and printed the DOF tables for every MM setting on all of my lenses and test a good many of them. It really only has an effect in very close up shots.
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Old Oct 18, 2009, 2:17 PM   #7
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Billy will probably want to comment on the review images. But, I'll take some time to discuss/address some of what you're seeing.

Quote:
Originally Posted by trigger1937 View Post
In all of these review, the claim is that they were all shot in RAW and processed in an identical manner.
Where did you get that from?

If you look at the top of the Sample Images page in the reviews, you'll see that in most cases (unless a sample is labeled otherwise), the photos are straight from the camera JPEG (not shot in raw). For example, if you look at the text on the SX20 review samples page, the "Large Fine quality" part of the text is referring to how the Image Size/JPEG Quality was set in the camera (this model gives you a choice of Fine or Normal JPEG Quality). Also, many point and shoot models don't even support shooting in raw. ;-)

For JPEG images, your Camera settings (sharpening, contrast, saturation, etc.), how a given camera processes images (amount/type of noise reduction being applied and more) will impact your results.

Quote:
The difference I see in both of the pictures you took can not be blamed on ISO setting. ISO will produce a GRAIN effect as in NOISE.
Most modern digital cameras are applying some amount of Noise Reduction during image processing. That will cause loss of detail as ISO speeds are increased from noise removal (which usually involves some smoothing of detail to help blur any remaining noise some so it's not as noticeable). Some cameras have adjustable high ISO noise reduction (off, low, normal, high), and some cameras don't let you control it when shooting jpeg (i.e., the manufacturer decides how much and what type to apply).

Quote:
My point is there is NO PICTURE in the SX20 samples that when viewed at 100% shows real sharpness.
I'd disagree. You really can't compare the portraits, as the only flash portrait (and you'll have higher contrast with a flash portrait) taken with the SX10 was using a much lower ISO speed setting, a different amount of optical zoom (and lenses are usually sharpest if they're not used at their widest or longest settings), different subject framing and more. There were no non-flash portraits from the SX10 in it's review samples, and the daylight portraits from the SX20 were at very slow shutter speeds. Considering the shutter speeds, the SX20 daylight portraits came out better than I would have expected if you're looking at images at a 100% viewing size. The comparable building photos look just fine to my eyes.

Quote:
I have taken 1 years worth of shots with my XSi and I still have the same problem...
A dSLR is not the same as a typical point and shoot for a variety of reasons.

In addition to differences in depth of field, you also have very different image processing with most dSLR models as compared to most point and shoot models.

By default, you'll usually have lower levels of sharpening, contrast, and saturation to maximize "real" retained detail. Don't confuse perceived sharpness and real detail. You can increase sharpening, contrast and saturation in most cameras if you want a "punchier" image straight from the camera. Or, use an editor to sharpen them and add contrast instead. But, increasing sharpness is mostly an optical illusion thats works by increasing contrast at edge transitions (which can destroy real detail if set too high).

Likewise, bumping up your Contrast settings can reduce Dynamic Range, resulting in loss of detail in shadow and highlights (because it makes brighter areas brighter and darker areas darker). Also, you can more easily blow individual color channels by bumping up your Saturation settings too high.

So, you'll find that most dSLR models use a more conservative approach to image processing compared to point and shoot models. Increase some of the defaults for Contrast, Saturation and Sharpening if you want a punchier image; or use an editor for more controlled results (so that you can vary the processing as needed for an individual image, taking viewing/print size into consideration, as you may want different levels of sharpening for different viewing/print sizes).

If you're trying to judge quality by how an image looks at 100% viewing size, without taking processing differences into consideration (which can take a trained eye with an understanding of the conditions and settings used for a specific photo and how the result may be effected), my advise is don't. Compare them at the size you're going to use more often. For example, compare an 8x10" print from camera A with an 8x10" print from camera B, especially with cameras that have different resolutions (so that you're not comparing smaller versus larger images when trying to view them at 100% on screen). Then, tweak camera settings or post process to suit your preferences. Also, if you're not comparing images taken in the same conditions, with the same camera settings, same subjects, similar lenses, optical zoom settings and more, you can easily jump to the wrong conclusions about a given camera model.

Quote:
...If there is a better area on this web site to post this kind of discussion please let me know so we can get more confirmation.
I'd probably read through this thread first. It has some discussion on sharpness:

http://forums.steves-digicams.com/wh...on-eos-7d.html

Also, this article by Petteri Sulonen makes a good read for a new dSLR owner:

Don't Be A Bozo

Then, when you take photos you're not satisfied with and still think it's the camera, start a new thread in our Canon dSLR forum with a downsized sample (or link to a larger photo stored elsewhere) if you want some comments on what you're getting from your XSi with a given lens and camera settings. Chances are, it's something you can change to improve on (for example, you're stopping down the aperture too much resulting in softer photos from diffraction limitations, or blur from shutter speeds that are too slow, problems with lighting, other camera settings, etc. There are many reasons photos may not look like you want them to. Usually, it's not the camera.
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Old Oct 18, 2009, 9:40 PM   #8
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Default Canon SX10 or SX20

JimC,... Please do not take my response as unappreciative or disrespectful of your knowledge. From a Photo professional to a rank amateur, there is so much information there it would take me months just to understand what you said. At this point it all doesn't matter.

All I want to know is how to shoot a portrait as well as billy shot with the SX10 IS. I have tried to shoot the same picture 100's of times at every focal length, every f stop, with and without flash, and I have yet to come even close.

As far as post processing, I have use Photoshop to enhance the sharpness of many images, but those changes are minimal compared to the quality of the image of his wife. The shot seems to focus on the right eye of the child, and the detail is so crisp, you can see each and every hair in the eyebrow. In her face and forehead, you can see each skin cell and every drop of sweat on her face,... and she is at the rear of the DOF. This is the image quality I want. I got something close to this with my G7, and I expected to get even better with the XSi,..that is why I bought it. No one ever said, "Don't expect your dSLR to shoot better images than your P&S.


I WANT to shoot pictures with high resolution, and the BEST image quality I can get such that I can crop where I need to and enlarge as far as I can go. That is what I do,,,.and I don't want any thing less.


My XSi has been a gross disappointment, and I will create a new post and start adding picture to show you that quite often I can't even get it to focus correctly, and THIS MAY BE THE MAIN REASON I CAN'T GET THE SHARPNESS I NEED. Sometime it will focus, next time it won't. As far as Canon is concerned,... the Camera is good, the lens is good,..therefore you must be doing something wrong.


If you can tell me how to shot a portrait as good as billy took of his wife and child with the SX10 is, with the XSi, I will send you a box of chocolate from Ghirardelli in San Franciscolace
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Old Oct 19, 2009, 9:18 AM   #9
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If you want a shot that looks like the portrait in the SX10 review, you'd need to shoot in similar conditions (i.e., that was indoors with the flash providing most of the light), at the same focus distance, using a zoom setting that gives you the same angle of view (so that you have as many pixels representing your subject).

That shot was at ISO 80, f/4, 1/60 second at a focal length of 15mm (giving you the same angle of view you'd have using an 84mm lens on a 35mm camera), at a focus distance of 134cm (around 4.3 feet).

If you wanted to duplicate it with your XSi, you'd need to zoom in towards the 55mm end of your kit lens to get the same angle of view (framing, so that the same size subject occupies the same percentage of the frame) at that focus distance (around 4.3 feet), and shoot at an aperture of around f/13.5 (to get the same depth of field), with a shutter speed of 1/60 second. In order to compensate for the dimmer aperture setting so that the flash provides roughly the same percentage of light, you'd need to increase your ISO speed to around ISO 800 with the XSi (although I'd probably leave it set to around ISO 400). Then, make sure *you* (and not the camera) are selecting the focus point (and focusing on the closest eye is a good bet).

Then, increase sharpening and contrast to taste (either in camera via the contrast and sharpening settings with your Picture Styles, or by using an editor later).

Frankly, I don't like portraits that look too sharp and contrasty, which is what you're going to get using a direct flash indoors with the flash providing most of the light at close range. But, if that's what you want, you should be able to duplicate it with your XSi.
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Old Oct 19, 2009, 9:59 PM   #10
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Quote:
Originally Posted by trigger1937 View Post
billy,.. If you actually did all the reviews of the SX10 & the SX20, did you also do the review of the XSi. In all of these review, the claim is that they were all shot in RAW and processed in an identical manner.
trigger,

I did also work with the XSi. We always use the highest quality JPEG settings avaialble, and all of our Sample Photos are straight out of the camera with No post processing (unless noted otherwise on the page). I'm not quite sure where you gathered the information above. We do on occasion shoot in RAW with some of the dSLR models, and then use the supplied software's "Auto" processing. This is mainly for comparison to the in-camera processing.

Jim seems to have covered everything else nicely

Good luck!
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