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Old Oct 22, 2008, 12:25 PM   #21
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I agree it's hard to believe. This is my first digital SLR, but before I worked for 6 years as professional photographer using small and medium format analog cameras, and I've got 9 years experience with digital photography, so I don't think I make any basic mistakes. I tried all kind of simple automatic modes (landscape, portrait) P mode, fully manual and fully automatic in great weather conditions, wide angle. Here are two pics in the same lighting conditions. First one with Sony DSC R-1, set for 24 mm and the second one with Canon EOS XSi, focal length equivalent 18 mm. Exposure in both cases: 1/200 sec and f7. Compare the quality
By the way my previous version of Sony DSC F707 5MP gives me just amazing images. One of them has been blown up to 2.5 x 5 meters banner. Fergot about it with my present Canon
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Old Oct 22, 2008, 12:29 PM   #22
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Here is another picture with Canon
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Old Oct 22, 2008, 2:11 PM   #23
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Those look like the lighting changed between them, and the framing is different. Light can make a huge difference in image quality. Here's a good read on the subject (but, it really doesn't touch on improved sharpness and contrast with better light, which you will tend to see). Make sure to run your mouse over the sample and look at the differences between them.

http://www.luminous-landscape.com/es...0seconds.shtml

You also had sharpening set to hard (+2) on the Sony shot, and you were still letting the camera decide what AF point to use from what I can see in the EXIF (and you can't expect unlimited depth of field with subjects that close, even at wider focal lengths shooting at f/10).

I'd make sure it's focusing on what you want it to before jumping to conclusions (select a focus point versus letting the camera decide what to focus on) and try sharpening the photo to taste later using an editor if you don't want to bump up the in camera sharpening (as you did with the Sony shot).

Test the AF to make sure it's working in controlled condtions if you're worried about a camera problem. But, I haven't seen any evidence of one so far, since you can't expect the camera to know what portion of the image you want to be sharp unless you tell it and I didn't see that any focus points were being selected in either of those samples). That doesn't mean you don't have a problem (it's just that I haven't seen anything suggesting that yet, since the AF point the camera is selecting is not being controlled in those).

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Old Oct 22, 2008, 3:05 PM   #24
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psykita, have you thought about letting someone else test your camera? I think a fresh perspective would help. Either your suspicions will be confirmed, or you'll get feedback that might help improve your images.

Trust me though, I know how you feel. I'm struggling with my XSi, which is why I'm following and trying to contribute to this thread. Right now, if someone asked me to take pictures of something as a favour, I'd have to dig out my Canon S2 IS... the image quality I'm used to getting from that camera is vastly superior to what I'm shooting with my XSi (in terms of colour, focus, clarity, sharpness). It's no competition.

But I also want very much to believe that I'm the source of the problem, not the camera. I've seen what other people are doing with my camera and my lens on sites like flickr, and I hope it's just a learning curve I haven't been able to navigate.

JimC: Maybe this is a dumb question, but where are you seeing that detailed EXIF data? The info available via right-click/Properties is limited.
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Old Oct 22, 2008, 3:50 PM   #25
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Quote:
JimC: Maybe this is a dumb question, but where are you seeing that detailed EXIF data? The info available via right-click/Properties is limited.
I'm using a free (open source) Linux based image management solution named digiKam to see that data, running under SimplyMEPIS 8.0 Beta 2 (a free linux distribution based on Debian Lenny) right now. You can see some of digiKam's features here:

http://www.digikam.org/drupal/about/features09

You can read more about SimplyMEPIS on their web site (and I'm setup with Windows Vista and Multiple Linux distros in different partitions on the same drives)

http://www.mepis.org

Note that SimplyMEPIS 8.0 Beta 3 was just released, too. See this announcement about it:

http://distrowatch.com/?newsid=05148

If you want to try it, it's relatively simple to shrink an existing NTFS partition using the including GParted utility to make room for Linux partitions on the same drive. You'll see more about how in the user guide here (it's for Mepis 7.0, but the same thing applies to the newer 8.0 beta versions, which use the same installer). You'll also see the user guide on your desktop if you boot into a Live CD . If you download the .iso file and burn Mepis to CD, and you can boot into it without even installing it since it can run from a CD (although it's much slower than way compared to a hard disk installation).

http://www.mepislovers.org/forums/user_manual/

Keep in mind that camera manufacturers don't publish the specs for what they save in the metadata portion of the image (especially, the Makernotes section). So, developers need to reverse engineer the data to try and interpret it. But, more and more image editing products are making a lot of progress in this area.

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Old Oct 22, 2008, 5:29 PM   #26
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P.S.

You do see QC problems from time to time with cameras and lenses. However, there are a lot of differences between a point and shoot and dSLR, in in areas like depth of field, how much processing the camera is doing (sharpness, saturation, contrast) and more. So, I'd rule out user error first.

Most dSLR models use relatively conservative image processing by default, and you're going to have a much shallower depth of field using one compared to a model with a smaller sensor. So, you'll need a bit of time to adjust to those types of differences.

If you think the Autofocus is off, the best way to tell would be to test it in controlled conditions, making sure to select the focus point versus leaving it up to the camera to "guess" what it should be focusing on.


This article by Petteri Sulonen makes a real good read for a new dSLR owner:

Don't Be A Bozo

Here some excerpts from it.

Quote:
... pictures are dull, or orange, or blue, or soft, or...
[snip]
...so you fire off an embittered message on 300D Talk, march back to the store, and either (a) return the camera, get your money back, and resolve never to listen to people who think DSLR's are worth a darn, or (b) exchange the camera for another unit, since yours must obviously be defective, or (c) exchange the camera and/or lens for the next better and more expensive model. If (b) or (c), you're almost certainly going to return to square one, and you'll be back at the store the next day, or the day after that, and as likely as not end up choosing (a).
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Old Oct 22, 2008, 5:51 PM   #27
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I just took another picture without any filters, 1/125 sec f8 and according to the depth of field chart:

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

for 18 mm everything within the distance of few feet up to
∞ should be sharp. Try the chart, put as the focal length 18 mm, calculate and check distances for f8,
This is not a case as you can see on attached picture. I had to re size the picture since it has 8.03MB so you don't see details, but i still keep original

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Old Oct 22, 2008, 6:21 PM   #28
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DOF charts are based on some assumptions, taking typical viewing sizes into consideration. Some users like to use a different Circle of Confusion setting if they're planning on larger print or viewing sizes.

But, frankly, I really don't see any problem with that sample. Don't confuse perceived sharpness with detail. Most sharpening algorithms are an optical illusion created by increasing contrast at edge transitions, and most dSLR models use more conservative sharpening settings by default (so that they're not destroying real detail and you'll have more flexibility for sharpening using an editor later).

Here is that last sample with a bit of USM (Unsharp Mask) applied. I'm just using an editor's default settings for it (so, you could get better results with a bit of tweaking).

Note that this is using a very low jpeg quality setting (45 on a scale of 100, with higher being better quality), in order to get the file size small enough to attach to a post here.

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Old Oct 22, 2008, 6:37 PM   #29
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Again, I'd test it in controlled conditions if you suspect a problem, making sure to select the focus point.

For AF testing, the chart momento posted a link to earlier in this thread is one way to test it. Personally, prefer to use books staggered on a table for testing.

For example, here is a shot using some of my wife's books. But, the ones in this example are a bit too reflective (which can fool some AF systems).

If the book in front of my target was sharper (I focused on middle book), I'd have front focus (with that lens, at the focal length, in that lighting, using the focus point I selected).

If the book in back of my target was sharper, I'd have backfocus (camera focusing behind my subject). The middle book (my focus target) looks sharpest, so the lens is fine in that lighting in this case (a quick AF test of a 100mm f/2 a while back on a KM Maxxum 5D):

http://www.pbase.com/image/51015183/original.jpg


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Old Oct 22, 2008, 7:59 PM   #30
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Thank you Jim for your comments. The depth of field is much smaller for macro pics, than for lanscape.

Here is the link to my flickr:

http://www.flickr.com/photos/gmacinski/

Two at the top are Canon and Sony DSC R- 10MP, before photoshoping. if you go to page 4 and 5 of my flickr you'll see more taken with my sony R-1, SLR like with Karl Zeiss lens. Actually all my sony pics start on page 4, pic #026 winter. As you can see soe of them are also macro and I'm really satisfied with sony R-1 with 14.4 x 24 mm sensor


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