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Old Nov 15, 2006, 9:16 AM   #21
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Bad in what sense? There not very artistic in an emotional sense to me. If they look dark or washed out to you it could be your setup. Doesn't take a "photographer" to
take a picture of a brick wall or stuffed animals



Gumnut wrote:
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were those test photos taken by photographers?
is it my monitor or do non of their photos look any good
no matter which camera/lens combination
or did i miss something?
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Old Nov 15, 2006, 10:38 AM   #22
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Quote:

ISO 1600
Pentax K10D
http://dc.watch.impress.co.jp/... .../image_for_link/71900-5035-14-2.html
1/25s / F5.6 / -1EV / ISO1600 / Program (MTF priority)/ AWB / 45mm

Sony A100
http://dc.watch.impress.co.jp/... .../image_for_link/56930-4072-18-2.html
1/60s / F5.6 / 0EV / ISO1600 / AWB / 70mm

Nikon D80
http://dc.watch.impress.co.jp/... .../image_for_link/61341-4415-15-2.html
1/40s / F5.3 / -0.67EV / ISO1600 / AWB / 62mm

Pentax K100D
http://dc.watch.impress.co.jp/... .../image_for_link/57352-4120-15-1.html
1/50s / F5.6 / -0.7EV / ISO1600 / AWB / 55mm



I saw all those ISO 1600 shots, and have to say that the K10D isn't looking bad at all; when comparing to the others in here.

What's your take on those ISO 1600 shots?
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Old Nov 15, 2006, 3:16 PM   #23
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RiceHigh wrote:
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The issue I have is the problems you mention above may not exist in the RAW image, but may instead be introduced by the JPEG compression algorithm.

I don't know if the compression was done by post processing the image or by performing the required compression within the camera. If this was in camera compression, then it may not perform as well as an off camera compression routine will.
DC Impress like to post in-camera jpegs. So, it would be fair to see how the DSLRs perform by *themselves*. And, comparison amongst different cameras would be fair enough, too.
Actually, there is still a huge issue with using in-camera JPEGs as a point of comparison... We don't know from the information posted what compression settings were used to produce the images. Were the posted images generated with the highest quality JPEG the camera can prodce (which means the least amount of compression) or were they produced with a higher compression ratio, which means additional distortion.

Using in-camera compression, you can manipulate the results too easilly. You can set the camera you like really well to it's highest quality compression settings, and set the other camera to it's lowest quality settings. All other things being equal, the camera with the lower quality settings will perform worse than the one with the highest quality settings. This can even cause a 10MP camera to behave worse than a 6MP camera does.

If I had both the raw images and the compressed images, I can tell you quantitativly how well the compression works, and how much distortion is added to the raw image by the in-camera compression algorithm.

In any event, since I shoot in raw mode exclusivly, I'd rather see the raw imges off the camera than compressed images.

Paul
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Old Nov 16, 2006, 9:35 AM   #24
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pbender wrote:
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Actually, there is still a huge issue with using in-camera JPEGs as a point of comparison... We don't know from the information posted what compression settings were used to produce the images. Were the posted images generated with the highest quality JPEG the camera can prodce (which means the least amount of compression) or were they produced with a higher compression ratio, which means additional distortion.
[align=left]But isn't that a RAW converted image can even have many more things to be changed/tweaked, besides only the compression ratio you mentioned and so on?

Regarding the compression ratio for the Pentax images, simply use a Pentax Photo Browser to check, it is in the EXIF data!

[/align]
Quote:
Using in-camera compression, you can manipulate the results too easilly. You can set the camera you like really well to it's highest quality compression settings, and set the other camera to it's lowest quality settings. All other things being equal, the camera with the lower quality settings will perform worse than the one with the highest quality settings. This can even cause a 10MP camera to behave worse than a 6MP camera does.
[align=left]Regarding the manipulation of test results, we must trust (the integrity of) the reviewers here. Anyone can actually manipulate results to certain extents if one intends to and wish to. So, sometimes when we are seeing reviews that are full of praises (which are in a very "positive" tone) and most sample photos posted are excellent without any problems seen, then the readers should be aware (that those "perfect" sample shots are carefully selected and/or created, e.g. exposure bracketing, by MF and so on!!

[/align]
Quote:
If I had both the raw images and the compressed images, I can tell you quantitativly how well the compression works, and how much distortion is added to the raw image by the in-camera compression algorithm.

In any event, since I shoot in raw mode exclusivly, I'd rather see the raw imges off the camera than compressed images.

Paul
Any reviewer(s) so far post RAW sample images/files by the way?? (I'm afraid there is none for major sites!)

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Old Nov 16, 2006, 9:38 AM   #25
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Thanks for the summary and these are interesting (to compare). However, I would rather to compare low ISO quality first, which is more important.

RiceHigh
http://www.geocities.com/ricehigh

rhermans wrote:
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Just found these links on the dpreview pentax forum, and thought that they might give some other views (sorry for the color but couldn't get the copy displaying correct)


Warning: Since exposures of the following samples are inconsistent, these may not be not a good comparison. But in case someone wants to see high ISO samples of other cameras on the same review site, perhaps it could be a reference more or less.

ISO 800
Pentax K10D
http://dc.watch.impress.co.jp/... .../image_for_link/71898-5035-14-1.html
1/10s / F5.6 / -1EV / ISO800 / Program (MTF priority)/ AWB / 45mm

Sony A100
http://dc.watch.impress.co.jp/... .../image_for_link/56928-4072-18-1.html
1/30s / F5.6 / 0EV / ISO800 / AWB / 70mm

Nikon D80
http://dc.watch.impress.co.jp/... .../image_for_link/61339-4415-15-1.html
1/20s / F5.3 / -0.67EV / ISO800 / AWB / 62mm

Pentax K100D
http://dc.watch.impress.co.jp/... .../image_for_link/57350-4120-14-3.html
1/25s / F5.6 / -0.7EV / ISO800 / AWB / 55mm


ISO 1600
Pentax K10D
http://dc.watch.impress.co.jp/... .../image_for_link/71900-5035-14-2.html
1/25s / F5.6 / -1EV / ISO1600 / Program (MTF priority)/ AWB / 45mm

Sony A100
http://dc.watch.impress.co.jp/... .../image_for_link/56930-4072-18-2.html
1/60s / F5.6 / 0EV / ISO1600 / AWB / 70mm

Nikon D80
http://dc.watch.impress.co.jp/... .../image_for_link/61341-4415-15-2.html
1/40s / F5.3 / -0.67EV / ISO1600 / AWB / 62mm

Pentax K100D
http://dc.watch.impress.co.jp/... .../image_for_link/57352-4120-15-1.html
1/50s / F5.6 / -0.7EV / ISO1600 / AWB / 55mm

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Old Nov 16, 2006, 2:42 PM   #26
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RiceHigh wrote:[align=left]
Quote:
But isn't that a RAW converted image can even have many more things to be changed/tweaked, besides only the compression ratio you mentioned and so on?
[/align] [align=left]Actually, no.
[/align] [align=left]By definition, a RAW image is whatever information comes off the image sensor in an uncompresssed format. This is the reason a RAW image is so much larger than a JPEG image of the same size.
[/align] [align=left]Compression ratio is only important for JPEG because JPEG is a lossy compression algorithm. Not all compression algorithms suffer from this problem.

[/align] [align=left]
Quote:
Regarding the compression ratio for the Pentax images, simply use a Pentax Photo Browser to check, it is in the EXIF data!
Perhaps it is, but some of us can't run the Pentax Photo Browser software you mention.
[/align] [align=left]The information may very well be available to me, but I'd have to dig for it. It is much better to have the reviewers mention the settings they used.
[/align] [align=left]
Quote:
Any reviewer(s) so far post RAW sample images/files by the way?? (I'm afraid there is none for major sites!)
[/align] Perhaps not, but that doesn't mean they shouldn't be posted.

Paul
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