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Old Apr 24, 2007, 3:35 PM   #1
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First off, i know this is the wrong forum but I just wanted share this.

I've been playing around with ps3 ((arrived yesterday - it's nice to
have a job where you can get those toys and your boss pays :G ))
and found out a strange thing.

There seems to be a difference between the way images are saved as jpg.

Below are two images to show the difference.


http://farm1.static.flickr.com/198/4...304fdd60_b.jpg
Saved in photoshop cs3 , using Save as jpg


http://farm1.static.flickr.com/208/4...6efc47c6_b.jpg
Saved in photoshop cs3 , using Save for web and devices

The second one is much closer to what I see in photoshop. The jpg seems to have the color profile included. I haven't tested this with ps2 but this might change the way I save images.

To say it again both images are saved jpg of the same dng file without any adjustments inbetween.

Any remarks are always appreciated

Ronny


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Old Apr 24, 2007, 4:01 PM   #2
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I believe the problem is to do with colourspaces not being properly configured in your new install of CS3.

I've noticed similar problems too when using save for web in a new install of CS2

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Old Apr 24, 2007, 4:03 PM   #3
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rhermans wrote:
Quote:
The second one is much closer to what I see in photoshop. The jpg seems to have the color profile included. I haven't tested this with ps2 but this might change the way I save images.
Actually, I believe the first one is the one with the color profile. By default, when Photoshop opens an image it will apply a color profile, probably set to "Windows RGB" or "Monitor RGB". Profiles are mainly used for print application, to simulate what the image would look like on different printers, but you can also use them to simulate how the image would appear on different displays like on a Mac.

When you simply "save as JPG", you have the option of embedding a profile. This profile is only read by Photoshop, so when you display the image in another program (like a web browser), you are seeing the original RGB data.

When you "save for web", it applies the color profile and alters the RGB data so that it will display the same in programs that do not support Photoshop's profiles.

Go into Photoshop's color settings and take a look under "Color Management Policies". I'm guessing next to "RGB:" it probably says "Convert to Working RGB". I have mine set to "Preserve Embedded Profiles" which in the case of JPGs from a digicam, should not embed a profile. I think this will make the "Save as" JPGs look the same in your browser as they do in Photoshop.

Usually when saving for the web, the "Save for web" option is a better choice, but in the case of this forum it's not a favorite as it strips out the EXIF data so nobody can tell what settings you used on your camera. Otherwise, I'd say just stick with that for posting images.
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Old Apr 24, 2007, 4:08 PM   #4
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ronnie,
ck your compression ratios. i think that the problem. the first one's size is 281k. the second is 321k. saved at the same ratio the first should be at least 10k larger because it retains the exif info.

roy
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Old Apr 24, 2007, 4:15 PM   #5
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i'd forgotten the color profile but it save it also by your choice. i shoot in aRPG and PS is setup to use aRGB but when i save the shoot i don't embed the profile because unless your monitor is set up for it you will not get as good of pic viewable. i think corpe has this one nailed.

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Old Apr 24, 2007, 4:24 PM   #6
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I double checked my Photoshop settings just in case. It's been a long time since I've had to deal with that stuff. Under Color Settings, you should probably be using the North American General Purpose settings. You want your RGB working space to be sRGB (sRGB IEC61966-2.1 is what it says on mine). Some people might suggest using Adobe RGB (including a guy I listened to at a Photoshop seminar) but that is a very bad idea.

Just to be sure of what's going on, open up one of your camera JPGs and go to Edit - Convert to Profile. Let us know what it says under Source Space, Profile: (I'm assuming PS 3 works the same as PS 2). You want it to be sRGB.
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Old Apr 24, 2007, 4:32 PM   #7
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ok, checked the color profiles

they are setup up to keep the existing color profile, and they are identical to the ps2 settings (where I don't have the difference)

maybe there are some more settings to search in the ps3 version, but the menu's seem to be exact te same.

it's now just midnight here so it'll be something for tomorow.

thanks for the help, and all suggestions are still welcome.

Ronny


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Old Apr 27, 2007, 2:40 AM   #8
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Just coming back to finish this story.

It was a problem with the colorspaces,

but because I start of mostly from raw the problem was in RAW4.0,
here I exported the image in adobe RGB to photoshop.

Ps kept the colorspace, even when it was set as sRGB so when saving to jpg
the color's changed.
When saving using save for web, ps does a conversion between to the sRgb colorspace resulting in the difference above.

Now converting the image from adobe RGB to sRGB in Ps would be a solution but
to keep it easy I've set Raw and Ps both to work standard with sRGB and this works out good enough for me.
Most of the shot's I take are for the web some for a printing service but they have send me their printers colorprofile, and I always archive the raw files.

Ronny
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Old Apr 27, 2007, 10:05 AM   #9
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From what I have been able to see in trying to handle other people's images for show and tell, when PS saves for the web it strips all EXIF information. No camera, no colorspace and most important (from my point of view) no copyright.

Why do I think about this? If you have an image posted to the web and someone decideds to use it - professional outfits - will check for copyright before deciding for themselves that your image is OK to mess with. By embedding your copyright into the EXIF - you can lay claim. At 150,000 USD per instance fines - it can get to be quite expensive.

For example - one of my friend's wife copied an image off of a Getty site and put it on her personal web site (advertising her management consuting business). It had been out there for a few years - Well he got a demand from Getty last week to remove the image and pay Getty 1,100 USD - or he could pay 2,000 USD and continue to use it for some period of time (I just do not remember). They warned him that if the payment was not made that they would sue and he would be looking at Federal fines of 150,000 USD and other associated costs. Always include your copyright - many tools allow you to do this.

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Old Apr 27, 2007, 5:28 PM   #10
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When I tried it, both images were identical.
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