Why do these images look different?

Hello everyone again,

A short while ago I posted regarding why my images look different on different PCs. I've corrected the brightness & contrast settings on my CRT monitor but left the LCD Laptop screen as it is.

Anyway - the screenshot below shows the same image (although x/y offset may differ slightly). The brighter one is what I see in a blitzplus application (ie my game). The darker one is what I see on the *same* monitor but through a simple image viewer (IrfanView) as well as a paint program.




In both cases I am using the CRT monitor as my primary display with the 'desktop' being extended onto the Laptop LCD display.

Does anyone have any ideas why the same bitmap / jpg /png would look completely different on the same PC and monitor depending upon which application is in use?

EDIT - tried it in blitz3d and it looks the same as the blitzplus version.

Could it be related to the picture bits?

I don't know - it also looks like the 'brighter' one if I set it as a background image in milkshape3d.

Edit - it looks like the darker one in Poser 4.

This is a bit weird?

Another EDIT - If I save it as a jpg in IrfanView instead of a png file then it looks like the darker image in milkshape3d, if I use the original PNG then it looks like the brighter one?

A further EDIT - it may be something to do with XSI's PNG exporter because if I change the image from PNG to JPG in Irfanview then the 'darker' image is what is seen in blitzplus?

I'd be interested to hear why this could happen?

Could you upload this picture somewhere? I'd like to take a look.

The picture is a little large to upload (6MB png) - but I think it may be something to do with XSI's PNG exporter as if I resave the image as a png in IrfanView as a png then it looks correct?

oh oh oh I think I know this ;)

Either B+ or the Infranview are useing a dedicated setting within your graphics cards software. Both Nvidia and ati started to do this a few years ago, whereby you had the option, now though they often go to the NET and ask there servers what contrast and Brightness that app would like, and change it just for that.

I may be wrong, but obviously because it does it in the background without asking you, it would lead to these sort of differences that otherwise seem unexplainable.

PS I like the the Infranview one better

If an image looks different on the same monitor, but viewed with different programs, the problem may be embedded gamma information.

This is a notorious problem: png gamma correction.

Thanks for the info - I think you are right Floyd as when I've exported as JPG or BMP files I haven't had that problem - only with the PNG files.

H&K - I like the Irfanview one better also - that is how it was supposed to look.

Actually, There's another possible option:

- BPlus uses DirectX to render the image.
- Your image viewer most likely uses standard GDI.

Pretty much all video cards have seperate Gamma + color settings for the desktop and DirectX/OpenGL. (Although I'm not sure if windowed DirectX uses the same gamma as full-screen DirectX, or if it inherits the desktop gamma settings)

to view these settings, go to your display properties -> Settings -> Advanced
From there on out, the settings differ depending on your video card drivers. Look for a tab named 'color', 'gamma', or something similar.

Thanks xlsior but I think it turned out to be the PNGs as all I had to do was resave the PNGs in another program and they were then 'correctly' displayed in blitzplus/blitz3d alternatively if I used JPGs or BMPs then they also displayed correctly. It just seems to be the PNGs that Softimage exports on my machine.