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Old Dec 11, 2003, 1:28 AM   #11
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Thanks for the reply's. I have posted images: http://www.rcdgroup.net/~ggaldino/. The images are jpegs about 500kb each. The first three images are from the D10 and demonstrate my problem, the last (what I would consider "in focus" is from the Fugi S2. I took that last three images this weekend, all required sharpening in PS (I also adjusted the levels).

I do not zoom in to focus. I do use the center square focus and AF.

I am hearing that the images from the 10D are designed to be "soft". I recognize that there is a notable difference between an image that is "in focus" and one that is soft. I have seen example images from this camera that appear to me in focus, however I have not had consistent results thus far. My images are similar to images posted from SteveZ at http://www.stevesforums.com/phpBB2/v...ic.php?t=15906.

My photos resemble his and the results I am getting require too much sharpening in PS with the undesirable side effect of too much added noise/grain. (BTW, excellent article on unsharped mask in Digital Photo Pro, second issue). I understand that if sharpening is to be done, it is preferable in PS and that it is easier to sharpen than to soften a "camera sharpened" photo. I would expect, for the price of this camera, that I should get consistent, in focus images at the standard setting (no extra sharpening) and without PS sharpening. The image of the day 11/13/03 http://www.stevesforums.com/phpBB2/v...ic.php?t=16568 is what I would consider a focused image with sharp detail, however it is from the digital Rebel, and from what I have heard is that this camera is more of a consumer camera and "sharpens the image. Does this mean that the D10 cannot produce this image? Are others achieving results like this from the Rebel?

I have experience using other digital SLR cameras including the Fugi S1 and S2 and Nikon D1, and my experience with these cameras produces images that are in focus (I have posted an image from the S2 showing exquisite detail and what I would expect from the D10, in focus). However, this photo was taken with a Nikkor 60mm Macro. This leads me to believe that perhaps it is the lens that is the problem. I will soon find out, as I am comparing it head to head with my friend's D10 and lens.
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Old Dec 11, 2003, 8:30 AM   #12
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First of all, are all theses from the same lens?

o 1st picture is back focus - the garage door and lock are in focus
o 2nd picture is front focus - the Tonka/helmet is in focus
o 3rd picture can't tell - ie out of focus

What does the Canon zoombrowser indicate as the focus point? normally with the same lens it only front focus or back focus, and not both... :?
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Old Dec 11, 2003, 11:53 AM   #13
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I believe that the same lens can back focus at one mm length, and front at another. But it should be consistant at the same focal length (and aperture?)

Maybe my eyes are going, but I thought the first picture wasn't bad. Of course, if that was after sharpening was applied in PS, then that is another matter. The text on the shirt is out of focus, but I didn't think the face was that bad.

The second on does have a problem, though.

The third seems to have a bit of motion blur in the helmet. At least the blur on the edges seem that way to me.

The best way to do focus testing is in controlled situations. If the camera has a problem, it will do it consistantly for a given set of settings in the camera/lens. Often a ruler is placed diagonally across a table with something at the center of the ruler used to focus on (a box of cerial or some other object with good contrast to focus on. Note that the ruler is not what you focus on, it's the object with good contrast and good lighting (to allow a high shutter speed.) The question isn't if the lens is soft, its if the camera is focusing incorrectly.

Then take some pictures at different distances, with different focal lengths and different apertures.

There is a site about measuring your AF system:
http://www.canondslr.com/articles/m-dream/

I thought I had a link to a better one, but I can't find it. Pity, as it was described by a Canon support person as basically the same way they do it in the repair shop.

Eric
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Old Dec 11, 2003, 1:51 PM   #14
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Quote:
I believe that the same lens can back focus at one mm length, and front at another. But it should be consistant at the same focal length (and aperture?)
This is called tolerance and not front/back focus and is the limitation of a particular lens. 1mm is less than the lenght of an eyelash (witn no mascara!). Even if you give the lens a 5mm sloppiness, this is no where near the degree of out-focus in the images posted wich are in the orders of 10cm or more!

... Something really fishy here! :?
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Old Dec 12, 2003, 12:00 AM   #15
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I just wrote a reply, but erased it because I now see where the confusion is. Let me restate what I said so it's clearer.

A single lens can front focus at a certain focal length and then back focus at another focal length. I haven't experienced this, but I've been told it's true (and seen pictures that demonstrate it.) I trust the people who said it (and did the tests.) In the two cases I've read about, they were at different ends of the zoom.

I said "one mm" when I really meant "one focal length". I've been strung out on drugs for a viral bronchitis recently, so I can't claim all Iíve written recently has been the most well though out prose.

Eric
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Old Dec 12, 2003, 10:52 AM   #16
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Eric

You need a macro lens for adjusting millimeters, with a normal lens it's very tough (if @ all possible) especially with a long zoom at 5-10m away!

... Check the distance scale engraving on your lens and see if you can adjust to within 1cm (or the AF), let alone a fraction of a mm. :?
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Old Dec 12, 2003, 6:49 PM   #17
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I took a look at your first three images. I have a modem connection so thats about all I could stand to wait . The images definitely look soft for a 10D. Whats worse is that you say they have been sharpened some!

There are two things I would try.
1. Borrow a lens from someone. Go to a local shop with your camera and they will most likely let you take some shots there.

2. If that is not your problem I would try resetting the camera.. or
a. - Check what parameter is being used and that sharpness is not turned all the way down.
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Old Dec 13, 2003, 9:03 PM   #18
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Quote:
Originally Posted by eric s
I thought I had 7a link to a better one, but I can't find it.
I don't know if this is the site you mention, but it has a pretty good testing methodology... plus you can download a target from his site.

http://www.photo.net/learn/focustest/

-jb
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Old Dec 13, 2003, 9:21 PM   #19
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Quote:
Originally Posted by ggaldino
...however it is from the digital Rebel, and from what I have heard is that this camera is more of a consumer camera and "sharpens the image. Does this mean that the D10 cannot produce this image?
No, it doesn't. The 10D has defaults set differently than the 300D. Adjust the 10D's processing parameters to match those of the 300D, or, better yet, your own tastes.

The contrast, saturation, and sharpness are "bumped up" a bit on the 300D to make images better directly from the camera. Increase these default settings on your 10D to match your taste. The basic settings are similar on the two cameras, only the default settings are different...

See page 56 in the 10D owners manual. Maybe start by increasing the sharpness... take a shot... see if it looks good... tweak to suit... etc...

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