I don't understand what I have to do. I examined in 800x zoom with GIMP, but it doesn't give me any hint about the answer.
Could someone give me some hints on how to proceed? Where do I have to focus on?
Didactic Green
You're on the right track. The letters are exactly as important as the digits. Ignore the fact that it's hex; try putting it into decimal and see if you spot something (a very basic something; don't stare too hard at the numbers, because they're not really what you're looking for).
The picture itself is quite suggestive, too; if you received this as a picture, ignoring the fact that the image is divided into pixels, are there any structures you can see in it? (sorry if I'm not being very helpful; it's quite hard to hint about the topic that this challenge is based on without revealing the whole thing!)
If you want further hints, you can private message me using the Private Messages link at the top of the page, and going to New Post.
The picture itself is quite suggestive, too; if you received this as a picture, ignoring the fact that the image is divided into pixels, are there any structures you can see in it? (sorry if I'm not being very helpful; it's quite hard to hint about the topic that this challenge is based on without revealing the whole thing!)
If you want further hints, you can private message me using the Private Messages link at the top of the page, and going to New Post.
There is no spoon.