How do I adjust the transparency of a layer in GIMP?

DoctorBeaver

I want to superimpose an image with partial transparency so that the layer below shows through. I've read the GIMP documentation and done what it says. I adjust the layer opacity slider but instead of gradually increasing transparency, the layer suddenly becomes totally transparent when I reach 50 on the slider. Above 50 it's opaque, below 50 it's invisible. There is no in-between.

I've tried with gif and jpeg images and the same thing happens.

Has anyone else come across this problem and, if so, did you find a solution?

brokenadvice

I can think of 2 Possible Problems.

The first is that your video card is somehow incompatible with GIMP. This is very unlikely, although a small possibility. If you export the image to a .jpg and it works, this is the problem.

If it is still funky, it is likely that you have the layer mode set to something other than normal. You can change this right above the opacity slider.

DoctorBeaver

It's an on-board video card but it's compatible with Compiz Fusion so it's not a duff 1 (the PC is a Sony Vaio desktop).

Layer mode is set to normal.

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