Hi Bert
Thank you for your answer. As you say, I mean light as in weight, i.e. small in Bytes. The fact is that I need to manipulate (add labels, put figures together,... nothing really difficult) some eps figures previously done with Mathematica and for this I am using Illustrator10 (it was the only way I found to do it without losing quality).
However when I save them, they get quite heavy (in Bytes). When I do that I try to select the simplest possibilities, but I am not an expert at all in the software. I have also tried to make an eps2eps which unloads them quite a lot but then the package psfrag of LaTeX (which is what I use to transform labels into whatever I want in a TeX form) does not recognise the labels.
I hope that this is clear enough. Otherwise I can explain further.
Best regards,
D.