what is the relation between blurring and depth ?

im never quite sure what is a good blur radius, when trying to create a bumpmap
usually i go for values between 10 and22

and what is actually Depth in technical terms ?

also: why does the Depth value in Gimp only go up to 65 ??
in PS, Depth is a percentage between 0 and 1000%

The Emboss and Bump map filters although different use similar methods. Have a look at this explanation at Grokking the GIMP.

that is a very good explanation, and really helps knowing how to use the sliders

thanks Odin for the link !

ive seen that page before
it does not really answer my questions

Odinbc - Thanks for the link very helpful.

Esper - just created two guide chart to see what happens with a different sized blur and with a different depth setting, All was created using the Bump Map filter.

thank you he4rty

i already did the same experiments here:
viewtopic.php?f=12&t=6202


but that still does not answer my question

if you do some experimentation with the layerfx bevel, you will see that a size of 10 is already pretty big
and im pretty sure that size = blur radius

which again means:
a small blur, even under 10 is enough

These two articles are related to bump mapping, they might not solve your issue but they are both experts on the science.
Simulation of Wrinkled Surfaces (PDF) by James F. Blinn
Simulation of Wrinkled Surfaces Revisited (PDF) by Morten Mikkelsen

Very interesting stuff ODIN, I just wish I had paid more attention to math in my day but I hated it in school. So, needless to say all that stuff is Greek to me...
It does explain a lot about the bump mapping though.