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Topic: Colour Issue
Username: ptrjong
Posted 2012-10-09 03:15:41 and read 4459 times.

Hi all,

It would seem that the colours in my photos have an abberration towards the red, but not over the whole spectrum; only towards the highlights/light parties.

Am I seeing things, of might this make any sense? If so, what might cause it? And what might fix it?

Thanks,

Peter 

Topic: RE: Colour Issue
Username: maaximm
Posted 2012-10-09 03:53:35 and read 4451 times.

Hi, try to correct in Photoshop tool "color change"

Topic: RE: Colour Issue
Username: dendrobatid
Posted 2012-10-09 05:38:16 and read 4431 times.

Peter
The curve can be used to give very precise colour control
An excellent tutorial here

http://www.thegoldenmean.com/technique/curves1.html

Mick Bajcar

Topic: RE: Colour Issue
Username: ptrjong
Posted 2012-10-09 06:04:32 and read 4422 times.

Hi Mick.

Unfortunately I'm using Photoshop Elements nowadays, and although Elements 10 has a basic Curves function, it doesn't offer separate colour channels.

There is a way of removing some red or adding some blue to the highlights, though. I think I'm starting to learn how to deal with this, but would rather prevent it in the first place.

Would this be a peculiarity of my camera type (Nikon D90) or even my copy?

Topic: RE: Colour Issue
Username: dlowwa
Posted 2012-10-09 16:12:17 and read 4355 times.

Quoting ptrjong (Thread starter):
Am I seeing things, of might this make any sense? If so, what might cause it? And what might fix it?

Could you perhaps post some examples? It sounds like you're describing chromatic aberration which is caused by flaws in the lens, but is often correctable with software. It would be best to see some examples to be sure.

Topic: RE: Colour Issue
Username: scopedude
Posted 2012-10-09 16:55:50 and read 4346 times.

Quoting ptrjong (Reply 3):
There is a way of removing some red or adding some blue to the highlights, though. I think I'm starting to learn how to deal with this, but would rather prevent it in the first place.

That sounds like chromatic aberration from the lens. I personally use LR 4.2 and it removes this kind of aberration very well. Just use either the lens profile and/or tick the Remove Chromatic Aberration box. Sometimes atmosphere can cause this kind of effect too.

Topic: RE: Colour Issue
Username: ptrjong
Posted 2012-10-09 17:01:03 and read 4346 times.

Hi dlowwa,

I haven't noticed differences with different lenses, so I wouldn't think it's a lens problem.

This one is straight from the camera, only resized.

http://www.horizonten.nl/pix/204.jpg

The light parties seem a bit too red, and the dark parties a bit too blue. To be honest I don't see it myself, but the pixel info confirms it to some extent, and this often seems to be noticeable for you screeners, at least after my editing.

If you tell me this picture is fine colour-wise, then I'm obviously over-editing at some point.

Peter 

(Mods feel free to move this to the Feedback forum if you must, although I think it's a pity, since this forum is so dead.)

Topic: RE: Colour Issue
Username: scopedude
Posted 2012-10-09 18:41:59 and read 4335 times.

That might be atmospheric, high humidity in the air causing such aberration. It's like shooting through a giant lens.

just my 0.02  

Topic: RE: Colour Issue
Username: dlowwa
Posted 2012-10-09 19:12:23 and read 4333 times.

Quoting ptrjong (Reply 6):
If you tell me this picture is fine colour-wise, then I'm obviously over-editing at some point.

No, I definitely notice the pink cast you're talking about. The atmospheric conditions (i.e. very low contrast) may be exacerbating it. Can't say for sure what's causing it, but possibly camera related. If you have the raw file, that would be pretty useful in determining whether it's that or maybe something else. You can send me it if you do.

Topic: RE: Colour Issue
Username: ptrjong
Posted 2012-10-10 00:11:37 and read 4316 times.

Thanks guys. I don't think this is limited to this particular day.

Dlowwa, where can I send the RAW file to? Thanks.

Topic: RE: Colour Issue
Username: dendrobatid
Posted 2012-10-10 00:40:08 and read 4314 times.

Peter
I can see the cast too though it is not much at all and I would find that very simple to correct just using colour balance.

Quoting ptrjong (Reply 6):
If you tell me this picture is fine colour-wise, then I'm obviously over-editing at some point.

That could be an issue ! If you are boosting the saturation that will exaggerate any cast, quite a common problem too.

Mick

Topic: RE: Colour Issue
Username: dlowwa
Posted 2012-10-10 01:07:35 and read 4313 times.

Quoting ptrjong (Reply 9):
Dlowwa, where can I send the RAW file to? Thanks.

Send me a message and I'll give you my email.

Topic: RE: Colour Issue
Username: vikkyvik
Posted 2012-10-10 08:42:30 and read 4273 times.

Quoting ptrjong (Reply 6):
This one is straight from the camera, only resized.

http://www.horizonten.nl/pix/204.jpg

The light parties seem a bit too red, and the dark parties a bit too blue. To be honest I don't see it myself, but the pixel info confirms it to some extent, and this often seems to be noticeable for you screeners, at least after my editing.

I see the same thing quite frequently with my 50D. When editing the RAW file prior to exporting, I've gotten in the habit of tweaking the red channel a bit to reduce the cast. If it needs more, then when editing the JPEG, I'll either use color balance, or more commonly, I'll go to Levels, select the red channel, and move the midtones slider down to somewhere between .92 and .97, depending on how much correction is needed.

Someone else on here mentioned that technique, but I can't remember who.

The worst is shooting against an overcast sky. Those are a giant pain to color balance properly when everything seems to have a red cast.

Topic: RE: Colour Issue
Username: dlowwa
Posted 2012-10-12 23:40:55 and read 4159 times.

So, having seen the RAW file, it does seem that it is a very simple white-balance issue, which is of course easily fixed when converting from RAW (somewhat relevant to the other thread about shooting jpeg vs. RAW, as this kind of correction is typically much more difficult when working from a jpeg only). Vik, the in-camera white balance settings applied do have that slightly red cast you describe, but he's using a Nikon.

Compare to the version Peter posted above:

http://imageshack.us/a/img825/9272/204i.jpg

Topic: RE: Colour Issue
Username: vikkyvik
Posted 2012-10-13 00:22:28 and read 4156 times.

Quoting dlowwa (Reply 13):
Vik, the in-camera white balance settings applied do have that slightly red cast you describe, but he's using a Nikon.

I know, I was just mentioning what I usually do about it, since he seems to have a similar issue.

To fix that shot, did you just change the color temp? Or was there more to it?

Thanks.

Topic: RE: Colour Issue
Username: dlowwa
Posted 2012-10-13 01:44:14 and read 4153 times.

Quoting vikkyvik (Reply 14):
To fix that shot, did you just change the color temp? Or was there more to it?

Just the white balance in ACR. Temperature about the same, but tint more to the left (green).

Topic: RE: Colour Issue
Username: ptrjong
Posted 2012-10-13 02:45:23 and read 4146 times.

Thanks Dana.

Quoting dlowwa (Reply 15):
Temperature about the same, but tint more to the left (green).

So this should be the basic trick, both in Camera RAW and in my camera?

Topic: RE: Colour Issue
Username: dlowwa
Posted 2012-10-13 03:22:45 and read 4140 times.

Quoting ptrjong (Reply 16):
So this should be the basic trick, both in Camera RAW and in my camera?

It will depend on each scene, as light is never consistent, but for the image above that was all it took, yes.


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