Image editing programs output wrong color values

[NightBlaze]

Recently, the conversion to greyscale made by my image editing programs has been different from the ones done by my friend's. I usually check the color values to guarantee the readability of my work, and up until mid-December, they were the same as my friends who usually help me with feedback.

• The original image: https://i.postimg.cc/Z562DffG/image.png
• The result on my computer: https://i.postimg.cc/mDgnkTb4/image.png
• The result on my friend's computers: https://i.postimg.cc/R0R8vWxG/image.png

We did test across multiple programs and devices. On my friend's computers, the result is consistently different from mine on Photoshop, Clip Studio Paint and Paint Tool SAI, and consistent across themselves. Which means, my friends didn't get different results from each other, only from me, and all of their results were the one I presented above. Their machines are completely different, including in operating system (one is on Windows 10, the other on Windows 7).

I tested in two devices, my laptop and my computer, both on Windows 11. My computer has two monitors (a HDR and a non-HDR one, with no difference in result between them). It is equipped with a RTX 2060, a Ryzen 5 3600, and 16GB of DDR4 RAM. As per posting instructions (although it doesn't seem particularly relevent information to the problem), the BIOS version is American Megatrends Inc. P5.40, 09/07/2019, every system mentioned is 64bit, and my PSU is 650W 80+. I'm using a Kingston A2000 NVME SSD. My laptop, on the other hand, has a GTX 1050 Ti, a i7-8750H, and also 16GB of DDR4 RAM. On both devices, the results are the same as my computer, across every program I tested (Paint.NET, Photoshop and Paint Tool SAI). That means that across both devices, they were consistent with my first result, and different from my friend's computers every time.

Since the only thing that seemed to be in common between my desktop and my laptop was Windows 11, I tried to revert my computer to Windows 10. Upon reverting to Windows 10, the results were exactly the same as they were on Windows 11, with no exception. I tried to change color configurations on NVIDIA Control Panel, also to no avail.

TL;DR: Greyscale should be identical in every program and every device, as far as I know. Testing on two computers with different software and hardware, i get one greyscale result consistently. My friend's computers show a different result, which are the identical to each other, but different from mine. They are also testing on different software and hardware.

What's causing this and how do I fix it?

[RTX 3071]

Have you installed the ICC profile which comes with your display?

[NightBlaze]

2 minutes ago, RTX 3071 said:

Have you installed the ICC profile which comes with your display?

I'm not aware of anything of the sort. When I bought both of my monitors, I installed a couple of different ICC profiles, but they're both more than a year old, and I have since done many clean resets to my desktop. Considering the difference can be seen across multiple monitors (my friend's, and the three displays I have), happens in greyscale, and any image editing program can pick up the difference in the greyscale with the color picker, I wouldn't think the problem is related to color calibration. This problem didn't happen before December as well, and my ICC profile was consistent at least for a couple of months at that point.

[RTX 3071]

4 minutes ago, NightBlaze said:

I'm not aware of anything of the sort. When I bought both of my monitors, I installed a couple of different ICC profiles, but they're both more than a year old, and I have since done many clean resets to my desktop. Considering the difference can be seen across multiple monitors (my friend's, and the three displays I have), happens in greyscale, and any image editing program can pick up the difference in the greyscale with the color picker, I wouldn't think the problem is related to color calibration. This problem didn't happen before December as well, and my ICC profile was consistent at least for a couple of months at that point.

Problem might not be about the color calibration but problem is probably with exporting. I can see the difference on my phone (S7 Edge). Try exporting with the web setting on Photoshop, I can't remember what exactly it's called but there's a legacy option for that which should allow you to just export as sRGB and web shades without including any other profile data. Because I believe that exporting is done with the profile you selected for that document.

[mariushm]

besides differences in color accuracy, gamma, how well monitors are calibrated, if the monitor is on srgb vs dci-p3 or other, icc profiles ...

 

No, no reason grayscale should be identical ... it depends on the tool you use to convert to grayscale, if it uses dithering or not, and what kind of dithering.

 

Your original image has 4600 unique colors.

 

First grayscale picture has 252 unique grayscale colors, the second has only 207

Irfanview generates one with 222 unique colors by going with the "convert to grayscale" feature. But, you can use "Change color depth feature" and select a specific number of colors (256 is most common) and you can choose to enable dithering

 

 

So here's for example

Convert to grayscale - 222 colors :

 

 

change color depth , 65k colors, no dithering- 201 colors :

 

 

change color depth, 256 colors max, no dithering - 140 unique colors :

 

 

change color depth, 256 colors max, WITH dithering - 139 unique colors :

 

 

Up to you to determine which is more visually pleasing if you can even tell.  And btw my pictures are 25 KB, as irfanview lets you choose compression level for png output.

 

 

As a demo of what dithering can do... here's the picture with 16 unique colors (and 13 KB)

 

[NightBlaze]

1 minute ago, RTX 3071 said:

Problem might not be about the color calibration but problem is probably with exporting. I can see the difference on my phone (S7 Edge). Try exporting with the web setting on Photoshop, I can't remember what exactly it's called but there's a legacy option for that which should allow you to just export as sRGB and web shades without including any other profile data.

If I'm understanding you correctly, you're saying that the problem happens when I export the file I'm using to edit (e.g., psd or sai) into a flat image (png, jpg, etc). But every image I posted is a print screen. The difference happens in program, before any exporting, as soon as I use the greyscaling conversion tool (adjust settings in Paint.NET or Filter in Pain Tool SAI, for example).

[NightBlaze]

3 minutes ago, mariushm said:

besides differences in color accuracy, gamma, how well monitors are calibrated, if the monitor is on srgb vs dci-p3 or other, icc profiles ...

 

No, no reason grayscale should be identical ... it depends on the tool you use to convert to grayscale, if it uses dithering or not, and what kind of dithering.

 

Your original image has 4600 unique colors.

 

First grayscale picture has 252 unique grayscale colors, the second has only 207

Irfanview generates one with 222 unique colors by going with the "convert to grayscale" feature. But, you can use "Change color depth feature" and select a specific number of colors (256 is most common) and you can choose to enable dithering

 

 

So here's for example

Convert to grayscale - 222 colors :

 

 

change color depth , 65k colors, no dithering- 201 colors :

 

 

change color depth, 256 colors max, no dithering - 140 unique colors :

 

 

change color depth, 256 colors max, WITH dithering - 139 unique colors :

 

 

Up to you to determine which is more visually pleasing if you can even tell.  And btw my pictures are 25 KB, as irfanview lets you choose compression level for png output.

 

 

As a demo of what dithering can do... here's the picture with 16 unique colors (and 13 KB)

 

Sorry for the mistake, then. I thought there was a fixed formula for gresycaling. However, my results used to be consistent with both of my friends before December, and consistent across every software I used. Now, it's different from my friends, even if they're using the same software as me, they get the same result between themselves from different softwares, and I get the same result in every software. They get the same results between themselves on different hardwares, and I get different results from them (but the same between my own) on different hardware and software. I can't quite graps what kind of entanglement is happening, even if greyscale can be converted differently. Specially when, by what you said, it seems the formula could change from software to software, and the inconsistent happens in the same software,.with the same tool, running in different computers.

[RTX 3071]

12 minutes ago, NightBlaze said:

If I'm understanding you correctly, you're saying that the problem happens when I export the file I'm using to edit (e.g., psd or sai) into a flat image (png, jpg, etc). But every image I posted is a print screen. The difference happens in program, before any exporting, as soon as I use the greyscaling conversion tool (adjust settings in Paint.NET or Filter in Pain Tool SAI, for example).

Ok, which color space your work file is on right now? Are you using 8 or 16 or 32 bits on your workspace?

[NightBlaze]

2 minutes ago, RTX 3071 said:

Ok, which color space your work file is on right now? Are you using 8 or 16 or 32 bits on your workspace?

I haven't reinstalled Photoshop since I rolled back to Windows 10 yesterday, but previously, it was set to sRGB. However, I work 99.9% of the time on Paint Tool SAI, which doesn't ask for any color space upon creating a canvas, but I would guess it is sRGB. Both of my monitors are 8bit, and despite one of them being HDR, both are set to SDR. Sorry if this isn't the information you want, or not very useful.

[RTX 3071]

5 minutes ago, NightBlaze said:

I haven't reinstalled Photoshop since I rolled back to Windows 10 yesterday, but previously, it was set to sRGB. However, I work 99.9% of the time on Paint Tool SAI, which doesn't ask for any color space upon creating a canvas, but I would guess it is sRGB. Both of my monitors are 8bit, and despite one of them being HDR, both are set to SDR. Sorry if this isn't the information you want, or not very useful.

Hmm I've never worked with the second software you mentioned so I'm out of ideas right now. 

[NightBlaze]

1 minute ago, RTX 3071 said:

Hmm I've never worked with the second software you mentioned so I'm out of ideas right now. 

Thank you for your time answering, anyways!