no glossy:
with glossy:
Which V-Ray version are you using? Also what are the lights in the scene?
I suspect the blotches are a result from GI caustics though.
Best regards,
Vlado
Thanks for the reply,
I am using 1.47.03
I will dive into this in more detail a little later, just wanted to know if more people experienced these kind of effects.
The objects are imported cad files, imported with Powertranslators.
The objects are lit by vray lights.
I will do a test later when I have a bit more time if it has to do with the imported geometry.
Vlado, it seems to relate to GI caustics, like you said. Does this mean that I would need to use very high settings to get rid of this effect?
I would just turn GI caustics off.
You probabaly dont need them at all.
then GI light doesnt go through transparent objects. have you tried with max models rather than imported ones?
ooo yeah of course…hmmm that was stupid of me.
Half asleep at work… my bad 
Yes I did, I got the same ‘error’.
In this case I think it is best to not using glossy refraction, or hide them when calculating GI.
Do you have both refractive and reflective GI caustics turned on?
What happens when you turn off affect shadows? This option actually fakes refractive caustics, so when enabling it, refractive GI caustics are disabled automatically for that material (or so I tought).
its just strange seeing as how ive used glossy refractions before and never had this
Flipside, I am using only refractive GI caustics.
When I turn off affect shadows, the effect is still there, only less aparent.
Da_Elf, indeed it is strange, and I cannot remember having seen this before. I will try to post a scene tomorrow with minimal objects, if someone wants to take a look.
what scale are all your objects?
Have you tried to just quickly recreate the bottles out of splines?
Also it looks like they dont have inside faces…maybe true putting a shell mod on them and see if that helps.
The scale is cm. The bottle is about 34 cm heigh.
I’ve rebuild the object from a spline and a lathe modifier.
I attach a sample scene right here (max7):
Gijs,
Im having a look at your file now to see if i can see anything odd 
Gijs,
Found the problem.
Turn your max depth in your reflection/refraction up to 5 and the spots will dissapear!
interesting thing though, I switched the shader from blinn to phong and the spots re-appear. hmmmmm
will investigate further.
At least it works with the blinn shader! ha ha
ok now this is doing my head in.
The first time I open the file, hit render, i get the splotches. close max, reopen the file, hit render, no splotches. I didnt save the file in between.
I downloaded the file again, opened it, hit render, no splotches.
Weird.
Has anyone else tried this file?
Here is my file if someone wants to check it.
http://www.chrisjackson.nzarch.com/imageuploads/GI-trouble-cj.rar
thanks for looking into this
btw: the file you link to is 0kb