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Hi

i am forced to use a temporary monitor or my laptop for a while, both are not calibrated. One produces colder tones, other warmer. But I dont know which screen is closer to calibrated. Can you please look at this image and tell me if it goes into blues or reds? Thank you.

fresh-sea-bream-for-sale-at-a-local-fish

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It's not in the reds but actually on the green channel!

 

Just put it into Photoshop and checked the RGB values and their is an off green cast to it.

 

It can be corrected in about a minute and it looks miles better!

 

1) Stick it in PS

2) Add on an eye dropper point to the image just to the bottom right of the fin on the main fish

3) Add a curves layer

4) Go to the green channel and push it up ever so slightly and the cast will be gone

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57 minutes ago, vpics said:

I find that the lower one seems to have some highlights blown. 

 

 It's definitely got blown out highlights in the original as well but I'm intrigued by the fish-shaped catchlight in its eye.

 

It's definitely a strong magenta cast (adding green is the same thing as subtracting magenta). If I was the OP,  I would rework the raw image taking care of the overall contrast as well as the colour. A gray card is a very useful accessory.

 

 

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To check the colour cast, use an eyedropper tool on a neutral area such as the ice which should be pretty much even in RGB. The cast is magenta not red, as the red and blue values are pretty much the same but the green values are lower.  If it was a red cast, then the red would be higher than the blue and green. It looks red because of all the blood in the image. The simplest way to correct is to use the eyedropper as spacecadet has done in LR or equivalent. In Photoshop, rather than use curves, it is much easier to use the ACR filter in CC versions.

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27 minutes ago, MDM said:

 

 It's definitely got blown out highlights in the original as well but I'm intrigued by the fish-shaped catchlight in its eye.

 

It's definitely a strong magenta cast (adding green is the same thing as subtracting magenta). If I was the OP,  I would rework the raw image taking care of the overall contrast as well as the colour. A gray card is a very useful accessory.

 

 

Thank you. I am re-working these files on different monitor. I ended up tweeking the WB and tint. However, I disagree regarding the blown highlights in the top image. According to the histogram these are not blown, and I think it looks better / more natural like this - it is a fish under the light source - it needs stronger highlights.

Can you please clarify what is wrong with contrast on this image?

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1 minute ago, MDM said:

The cast is magenta not red, as the red and blue values are pretty much the same but the green values are lower. To check the colour cast, use an eyedropper tool on a neutral area such as the ice which should be pretty much even in RGB.  If it was a red cast, then the red would be higher than the blue and green. It looks red because of all the blood in the image. The simplest way to correct is to use the eyedropper as spacecadet has done in LR or equivalent. In Photoshop, rather than use curves which , it is much easier to use the ACR filter.

Thank you for your assistance. I tried using eye dropper in Capture One on ice and neutral parts of fish skin, but it was resulting in a strong green cast. I ended up adjusting WB and Tint.

 

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1 minute ago, Pietrach said:

Thank you. I am re-working these files on different monitor. I ended up tweeking the WB and tint. However, I disagree regarding the blown highlights in the top image. According to the histogram these are not blown, and I think it looks better / more natural like this - it is a fish under the light source - it needs stronger highlights.

Can you please clarify what is wrong with contrast on this image?

 

 I was looking just at the jpeg in Photoshop and the highlights on the back are right at 255, 255, 255. I don't know if they would be as high in the raw image. The texture gets lost a bit but this is a matter of taste really (not literally, I'm a vegetarian :))

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3 hours ago, Jools Elliott said:

I too found the highlights blown in all channels when looking at the jpeg.

 

Getting rid of the cast by Photoshop curves; Camera Raw curves or the Lightroom Curve would give you a far more accurate correction than using the WB and Tint.

 

I understand and you are correct I'm sure but the problem with curves is that a lot of people baulk at the thought, particularly working on individual channels. I think it's a psychological barrier really. Sliders are easier to comprehend and it is probably possible here to get a decent rendering on the raw image just with the WB sliders together with the Basic sliders as well without resorting to curves channels.

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The Kodak neutral gray cards come in a couple of sizes, the smaller of which easily fits into a camera bag or large pocket. Take a reference shot with that for use with a gray-balance eye dropper. Some software such as Photoshop allow you to save the curve as a preset to apply to other images shot under the same lighting.

If you have thumbnails opened with others, such as fish on ice for example, do yours look red/magenta by comparison?

 

P.S., bear in mind that a fish market will likely have fluorescent lighting with very low CRI and in that circumstance no amount of global correction will ever fully correct the color cast. Gray balancing will get you pretty close, though.

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1 hour ago, DDoug said:

The Kodak neutral gray cards come in a couple of sizes, the smaller of which easily fits into a camera bag or large pocket. Take a reference shot with that for use with a gray-balance eye dropper. Some software such as Photoshop allow you to save the curve as a preset to apply to other images shot under the same lighting.

If you have thumbnails opened with others, such as fish on ice for example, do yours look red/magenta by comparison?

 

P.S., bear in mind that a fish market will likely have fluorescent lighting with very low CRI and in that circumstance no amount of global correction will ever fully correct the color cast. Gray balancing will get you pretty close, though.

This was absolutely the case here - fluorescent lighting, but also mixed with a bit of daylight light and standard tungsten light. Nightmare. And yes, my images do look red in comparison to others. Fixing it now by replacing the affected batches.

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