For some reason, whenever I save a photo in Photoshop using the Web Jpeg option, it changes the colour/contrast/saturation of my shot. The original photo is already in 8-bit, so I'm not sure what the problem is.
The file size in your example is very small. How much JPG compression are you applying? JPG compression will average / change color values.
The simplest solution is the most obvious one: don't use save for web. Back in the days of dial-up shaving a few KB of header information made save for web worthwhile, but I haven't used it for years. I just resize and sharpen using a simple action I recorded then save as a level 6 -8 jpg.
What color space is your original versus the JPEG? I've noticed some color shifts when saving an image in Adobe RGB as a JPEG. I usually convert to sRGB first, then save the JPEG file.
Were you in sRGB prior to saving for web or did you allow it to happen automatically?
I agree with the comment about file compression. You're going from a 370K file size to a 38K size....that's a lot of compression. Compressing data throws information away.
I also never use save for web, first converting to 8 bit srgb @ 72 dpi @ 800 px file size, then use save as and select jpg. I typically use a save value of 8-10. I don't know if that makes much difference in color shifts, but that's the way I've always preferred to do it.
cgardner wrote:
The file size in your example is very small. How much JPG compression are you applying? JPG compression will average / change color values.
I realize this, but this is a rather large change. We're not talking about just noise.
I went back and tried different options: Mainly, Save-to-web, JPEG, with Max quality and there is still no change. Also, I tried using the regular Save-As with JPEG option, again, with Maximum quality and the blue is still lighter.
duranash wrote:
What color space is your original versus the JPEG? I've noticed some color shifts when saving an image in Adobe RGB as a JPEG. I usually convert to sRGB first, then save the JPEG file.
The listed (Source) profile indicates sRGB.
There is something else. It appears it's a problem with my workspace. When the image is previewed elsewhere, it gives me a light blue colour. But when it's viewed in PS, it gives me dark blue (this is AFTER saving).
There is a check box in your color settings dialog box that I would recommend that you check: Profile Mismatches: ASK WHEN OPENING. This will alert you to the fact that your image color space (aRGB) does not match your working color space and give you the opportunity to make the right decision (use sRGB working space in this case). There are other ways to accomplish this (like associating a new profile with the image), but this approach should get you back on track. You should not see drastic changes. Saving for the web can create either small changes or require a small reprocessing of your image to optimize it for a small format (or presentation on a display). You might use a curves adjustment layer to add back a little more of the contrast in the smaller image. This will help restore some of the saturation also. This is often a good practice. But, just to be clear, I think that your problem is that your image is in aRGB and you needed to change that before you went to output for web.
