Colour changing

A problem that occurs when I try to finish a pic.
After stacking I use my Nikon Capture NX2 (not photoshop!) to resharpen and smoothly change colours so that it looks like the original specimen.
I`m satisfied with the pic, watch it on my LCD screen and add it to mindat.

Then I`m wondering. The sharpness has gone - well this happens due to resizing - but more and more often the colours have changed even when watching it with the same LCD.

Take this one as example: [www.mindat.org]
While reworking its ok, maybe a bit too greenish but I can live with it. Adding it on mindat and its waaay to red!
Am I doing something wrong???

Make sure you are working in sRGB colour space, not AdobeRGB or any other colour space!

Or convert the final result into sRGB using photoshop if necessary (load image, go edit/convert to profile)

Jolyon

I might need to do a tutorial article on colour spaces and mineral images at some point - it's a huge issue to deal with. Mindat does not have the capability to automatically fix colour spaces (currently), so we rely on the images being uploaded in sRGB, and many people are not...

Jolyon

The situation is more complicated than this actually... If your computer is set up with a custom colour profile (calibrated monitor), then your web browser may not show any image accurately if it has no colour profile associated with it - and currently none of the resized images on mindat do.

For me to change this, I'll need to change the way we process uploaded images to use a completely different system. I think it's worth doing.

Jolyon

Thanks Jolyon!
I will not change this example pic as I think others will also want to see it so I changed another one with the same problem. [www.mindat.org]
The profile was Adobe and is now sRGB 1966-2.1. Unfortunately the red touch is still there.
Guess I must wait till my friend Harald Schillhammer will be back who calibrated my monitor!

Hi, Jolyon,

Several points on color space and their conversion.

1) Most of the photos are uploaded as JPEG images which uses the YCC color space. This color space is not sRGB.
2) If you have a profile assoiciated with you monitor, appropriate conversion should take place using the color management software in your operating system and monitor driver.
3) I use an AdobeRGB profile for my monitor and both of the images in the above messages appear normal when viewed on my display, i.e., no color shifts of green or red.
4) The sRGB color space was designed when CRT monitors were prominent and utilizes the color gamut of a CRT to it fullest. The newer LCD monitors have a much larger color gamut than sRGB and are more appropriate to AdobeRGB.

I would not recommend locking in the sRGB color space to you image library! The evolution in coputer displays, large gamut color spaces is going to continue into the future, especially with LED and/or OLED displays. The color conversion is properly done in the CCM of the operating system of the users computer and display system, NOT by the web host.

I really have to wait for Harald.
This afternoon I had the possibility to make the same test (original pic on a stick and compared with the pic on mindat) on a laptop. Normally I wouldn`t even recommend to use a laptop for reworking any stacked pic! But now I see that on the laptop there is NO colour difference at all, its just on my -new!- LCD.

This is strange, because I only calibrated the luminance and contrast. We have not saved any color profile. And, Chris, if you remember correctly, we did the same to your laptop.
Maybe the default display color space has been changed accidentally on your EIZO LCD. I have to give this another look as soon as time allows. I will also buy a new calibration device since my old one has a defective blue sensor.
Cheers

Harry