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Old May 7, 2008, 4:34 PM   #21
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P.S.

I'd also suggest taking photos with both cameras at their full resolution settings, with the same subject framing, lighting, etc., and then have them printed at around 8x10" at your favorite local vendor (for example, you can upload them to http://www.walgreens.com and pick up 8x10" prints at your local store around an hour later for around $2 per 8x10" print).

Then, you'll get a better idea of why manufacturers are using less aggresive sharpening algorithms and why you can get more detail by starting out with a higher resolution image for any given print or viewing size.

Unless you're starting out with the same framing (your subject fills the same percentage of the image), and comparing both images at the same viewing or print size (which requires downsizing of the higher resolution image if you're using a monitor so that your subject is at the same viewing size as it is in the lower resolution image), you're not seeing the difference a higher resolution sensor can make.

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Old May 7, 2008, 5:10 PM   #22
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The question is how you're comparing the photos you took at different sizes.

If you're viewing both at 100%, that's not the way to compare them. You'll want to downsize the full size image to the desired viewing size and compare them that way.

IOW, a downsized image from a higher resolution sensor should have more detail from a lower resolution image that has not been downsized, because of the way demosaic algoirthms impact the full resolution photo, with pixel information averaged together after downsizing for best results.

That's also the way you'll want to use images from a digital camera (downsize them for the desired viewing size, versus trying to crop them to get them small enough to fit on a screen). You start out with a larger image with the higher resolution model, so if you try to compare both at 100% viewing size, you're comparing apples to oranges (the subject in the higher resolution image will represent a much larger percentage of the screen compared to the subject in the lower resolution image if you framed them the same way, so that's going to look softer if you don't downsize it so that viewing sizes are the same).

As far as showing us full resolution images, that's an even better idea. The best approach for that would be to open a trial account with a photo sharing site like http://www.pbase.com and give us links to the images. They allow 10MB with a free trial account (which should be enough for a similar photo from both cameras).
Ok, i´ll try to explain EXACTLY what I do when comparing or checking pictures on my PC.

I know my way around Photoshop, but i dont use it for practical reasons, because it would take too long to load, and etc, etc. I use the default image viewer on Windows XP. I only use photoshop when comparing two images, side by side. Usually, I open one and them the other.

Concerning the Zoom comparation, lets take for instance a picture of my son. If i have a picture took 1,5 meters away from him, and the pic includes his head, shoulders, arms.

What I would do is zoom in on the image considering his eyes as the center of the image, and zoom in until only the eyes are displayed on screen. Them I would do exactly the same with the other picture taken from the other camera.

If im not comparing cameras, the only think I do is zoom in to a certain part of the object portraited to check how the detail is going. For instance, a picture of part of that tree in front of my window: i would zoom in 2 or 3 times on a given aread of the tree, usually the area on the center of the picture, and check the contour of the leaves, branches, etc.

Concerning the upload of the pics, i think 10 mb is not enough, but i will check out this site when i get home, in 1 or 2 hours. Someone suggested a certain flickr, but i dont know if that site allows big sized pics.


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Old May 7, 2008, 5:14 PM   #23
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JimC wrote:
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P.S.

I'd also suggest taking photos with both cameras at their full resolution settings, with the same subject framing, lighting, etc., and then have them printed at around 8x10" at your favorite local vendor (for example, you can upload them to http://www.walgreens.com and pick up 8x10" prints at your local store around an hour later for around $2 per 8x10" print).

Then, you'll get a better idea of why manufacturers are using less aggresive sharpening algorithms and why you can get more detail by starting out with a higher resolution image for any given print or viewing size.

Unless you're starting out with the same framing (your subject fills the same percentage of the image), and comparing both images at the same viewing or print size (which requires downsizing of the higher resolution image if you're using a monitor so that your subject is at the same viewing size as it is in the lower resolution image), you're not seeing the difference a higher resolution sensor can make.
I know that for printed outputs, the S5 will bring out excellent pictures. But as I mentioned earlier, i NEVER print any of the pics I take. I keep them exclusively for PC and TV viewing.

style="BACKGROUND-COLOR: #000000"Also as i mentioned earlier, the most common phrase on the reviews Im reading at Dpreview.com, that has a section on the review entitled Image Quality is something like: "unless you´re picky and like to do pixel peeping, you´ll be more than satisfaied with the regular prints of shots from this camera xyz".

style="BACKGROUND-COLOR: #000000"Seems like NO camera these days carries a good definition and detailing like the old ones.
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Old May 7, 2008, 5:17 PM   #24
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PS - but Jim, you didnt comment my post about that S5 picture with excellent definition and contour.

Do you agree that it was probably taken too close from the subject and probably using Macro??

I just cant wait to find a way to show you guys some of the 200 hundred test pics I already shot with this S5. Some of them are unbelivably horrible. And I know it could be counted on my lack of photographic talent, but im notTHAT stupid and know my way around my old faithfull A70.
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Old May 7, 2008, 5:24 PM   #25
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Jim (and everybody else), please check this other pic from Steves S5 samples:

http://www.steves-digicams.com/2007_...s/img_0235.jpg

The other pic you posted the link here, of a woman, was taking using the portrait option, and probably very close to subject and maybe using a tripod.

The picture above is very close to the kind of pics Im getting.

Notice how everything looks blurrish. The baby face, his skin. Theres not even close the amount of definition you saw on the girls picture.

Check specially the kids hands. See how they look moggy, like theres a fog around them!

The A70 would take this picture exaclty like the girls sample.




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Old May 7, 2008, 5:33 PM   #26
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You're still not getting the point.

If you downsize that same full resolution image from the S5 IS to the same resolution (dimensions in width x height in pixels) as you're taking the photos with the A70, you should see a much better photo than you'll have from the A70, if your subject is occupying the same percentage of the frame with the same lighting, exposure, etc.

You need to compare the images at the same viewing size, with the subject occupying the same percentage of the frame (which requires downsizing the image from the higher resolution camera model). ;-)

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Old May 7, 2008, 5:58 PM   #27
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For example, does this look soft to you? This is the same sample you posted a link to, downsized and very lightly sharpened (it would sharpen more). Keep in mind you've got a very shallow depth of field at a focus distance that close. To see how another model compares, you'd need to take the photo in the same way (subject occupying the same percentage of the frame, same lighitng, etc.).

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Old May 7, 2008, 7:07 PM   #28
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JimC wrote:
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For example, does this look soft to you? This is the same sample you posted a link to, downsized and very lightly sharpened (it would sharpen more). Keep in mind you've got a very shallow depth of field at a focus distance that close. To see how another model compares, you'd need to take the photo in the same way (subject occupying the same percentage of the frame, same lighitng, etc.).

Yes, I still think its soft, but now its also grainny.

Download it, and open with any image program you preffer, them zoom in twice. You'll see that the boys fingers are still blurry, but now theres grainy noise all over the place.

:-)
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Old May 7, 2008, 7:20 PM   #29
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Post photos from both camera models, taken with the same subjects and lighting, with the subject occupying the same percentage of the frame and lets take a look at how they compare.

As already mentioned in my last post, you also have to take depth of field (the portion of the image in focus as you get further away from your focus point) into consideration.

I doubt the A70 would handle that exact scene any better. You're looking at a smaller subject (the boy) at a close focus distance (probably focused on the closest eye). You don't have infinite depth of field with a camera shooting a closer subject. ;-)

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

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Old May 7, 2008, 10:56 PM   #30
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Ok, im back and I have more comments to share concerning the diferences between A70 and S5.

I noticed that the A70 is capable of, right out of the box, using P mode and AFAE off, producing sharp, detailed and well defined pictures of a human subject about 1 meter of distance without having to bother with manual focus, aperture, exposition, whatever.

The S5 can come "close" (i meant close, but NOT as good as) to the A70 in terms of sharpness, detail and defined contour of a human subject under the same circunstances, BUT to obtain that you need to necessarily use AV mode, set an aperture of at least 4,5 and overexpose the flash almost to the point of making a bad picture, and use a tripod. Only them I managed to obtain close pictures in terms of detail. Off course the S5 produces a better result if you are considering other aspects of the picture, but the main focus here is on detail and sharpness.

I have just shot a few pictures of a scene (flower vase, cell phones and S5 box on a table)with the S5 and A70on a tripod 90 cm away from the flower vase (center subject), and using various camera settings. I think this pictures will allow us to make a clear comparation of the two cameras hability to produce sharp and detailed pics. I currently trying to find a site to upload them. As soon as I find one, I will post the links here.

BUT......in the meantine, I found a few examples to ilustrate what i mean in terms of detail, contour, sharpness, etc, and how they variate from camera to camera. You will notice that the S5 and other canons are not the sharpest ones....



Nikon P5000 (my favorite of all samples so far):
http://www.steves-digicams.com/2007_reviews/nikon_p5000/samples/dscn0056.jpg

Nikon P5100:

http://a.img-dpreview.com/reviews/Nikonp5100/samples/Flash/Nikon_P5100_flashhead.JPG

Canon A720 IS:
http://a.img-dpreview.com/reviews/canona720is/Samples/Flash/IMG_1395.JPG

Sony H10:
http://a.img-dpreview.com/reviews/sonydsch10/samples/flash/DSC00864.JPG

S5:
http://a.img-dpreview.com/reviews/CanonS5is/Samples/Flash/IMG_0820.JPG

I wont make any comments because I think they are very clear to see. Just notice how the Nikon samples are waaaaaaaaay better.....


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