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Old Jan 6, 2005, 1:55 PM   #1
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This may initially seem like a no brainer question,but I have seen photos from a G6 (6+Megapixels) and a 20D (6+ megapixels - 16-35 Canon L series zoom). The G6 was sharper on Photoshop CS at 200% !!! What gives ?
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Old Jan 6, 2005, 2:22 PM   #2
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I don't have the expertise to answer this question, but I might ask--

Are these images of identical subject matter shot under the same conditions? Of course something shot at f/8 1/250 sec in the "sweet spot" of a lens would be sharper than something shot at f/2.8, 1/10 sec shot at either the widest or most telephoto of a lens. Use of a tripod, lighting conditions, distance to subject, all would make a difference.

Provide the images or give more information, and I'm sure someone more knowledgeable than I might give you an answer


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Old Jan 6, 2005, 2:33 PM   #3
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Couple of threads already running on this very same topic, there are other threads as well I just couldn't remember where they were(My rapidly advancing age is showing) :?

http://www.stevesforums.com/forums/v...mp;forum_id=58
http://www.stevesforums.com/forums/v...mp;forum_id=37
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Old Jan 6, 2005, 2:57 PM   #4
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The images from the G5 I used were extremely good. JPEG perameters and in-cameraprocessing in the G5, G6 or any other digicam is very intensive compared to what DSLR's do. They basically come out of the camera as finished images. You simply cannot expect that with a digital SLR- the makers don't build them do be that way, nor do many/most DSLR users want it that way.Once corrected and finished I very much prefer images from my 10D to what I gotfrom my G5, not to mention the WAYbetter AF performance.

I'm also willing to bet those images you saw from the G6 were shot at only ISO 50 or maybe ISO 100. Compare like images shot on both camerasat ISO 400. I think we all know which one would look better.
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Old Jan 6, 2005, 3:56 PM   #5
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"Are these images of identical subject matter shot under the same conditions"

Neighbor has a G6. We both shot a pic of his new car. I can't speak for his automatic camera with a fixed lens, but I shot my 20D with a 16-35 canon l zoom lens on manual 250th @ f8. Exposure is fine. However, it goes soft all over when zoomed in all the way for review. On Photoshop (browse) at 200%, his computer, it looks terrible. while his G6 looks much, much better.
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Old Jan 6, 2005, 4:01 PM   #6
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"You simply cannot expect that with a digital SLR- the makers don't build them do be that way, nor do many/most DSLR users want it that way.Once corrected and finished I very much prefer images from my 10D to what I gotfrom my G5, not to mention the WAYbetter AF performance"



His ISO was 50, mine 100. I just cannot get Photoshop to correct a soft image. Shouldn't the image be sharp from the camera, or why focus ?
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Old Jan 6, 2005, 4:18 PM   #7
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No, you can't get PS to correct an out of focus image, but if the image is not particularly sharp, there are a number of sharpening techniques to correct that (see, for example, the sharpening actions at atncentral.com)

Do you have any in-camera sharperning turned on?

Was the whole image soft, or did you have the AF point set to focus on something other than the car?

It appears that Fred Miranda thinks the 16-35 is a pretty darn good lens.

http://www.luminous-landscape.com/re...es/16-35.shtml
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Old Jan 6, 2005, 5:05 PM   #8
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If the image is focused, has enough DOF and is exposed correctly, but seems soft you should try to hit it with some unsharp filter. One method is to convert the image to LAB, apply the unsharp filter aggressively to the L channel, then apply some gaussian blur to the AB channels. Reconvert to RGB.

Digital ISO is a fiction, it is the sensors apparent speed of capture compared to film. Trying to comparethecapture on a 1.1/8 sensor to a aps-c sized sensor is like trying to compare apples and wet trout.

filmer wrote:
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His ISO was 50, mine 100. I just cannot get Photoshop to correct a soft image. Shouldn't the image be sharp from the camera, or why focus ?
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Old Jan 6, 2005, 7:18 PM   #9
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I don't think focus is the word I want here. The AF was on automatic and center weighted. It appeared sharp in the lens, though the image looked like someone had smeared vaseline evenly over the entire area. I'll try the LAB correction, but am still amazed that a sharp lens can't shoot a sharp pic. Thanks to all for your input and suggestions.
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Old Jan 6, 2005, 7:52 PM   #10
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This is from the Canon EOS pdf file at the following link (Getting the Most from your EOS-1 Class Digital SLR):

http://www.photoworkshop.com/canon/EOS_Digital.pdf

Begin Quote*******************************************

[align=left]Apply post-process sharpening effectively:[/align]

[align=left]Canon EOS digital cameras have an anti-aliasing filter installed on the image sensor.[/align]
[align=left]This filter improves color rendition and practically eliminates moiré. The liability is a[/align]
[align=left]slight reduction of sharpness. To reduce the softening effect of the anti-aliasing filter we[/align]
[align=left]recommend applying an unsharp mask to the image in Adobe
® Photoshop®. Although[/align]
[align=left]there is no such thing as a "best" setting for all applications, we suggest the following[/align]
[align=left]as a starting point:[/align]
[align=left]Amount: 300%[/align]
[align=left]Radius: 0.3 pixels[/align]
[align=left]Threshold: 0 pixels[/align]
[align=left]End quote*****************************[/align]
[align=left][/align]
[align=left]Also, as I understand it, some of the consumer digital cameras have the jpegs processed at what would be equivalent of setting sharpening to +2 on the 20D. They also pump up color saturation (+1) andcontrast (+1).[/align]
[align=left][/align]
[align=left]Regards,[/align]
[align=left]Bob[/align]
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