What do you recommend?
Minimum 80 cm.

I thought of silver ones, lmk your opinion.
Also need some tips on brands.

depends on ur budget first

Let's say 50-80 euro per umbrella.

I own several umbrellas. If you are shooting studio and have space I recommend this one: http://www.adorama.com/PFRUT60.html

It's inexpensive yet seems durable. I actually have 2 of them. It's a convertible umbrella (you look cool). No actually, you can shoot through it or you can keep the black lining on the outside and shoot into the umbrella and hence bounce light back.

That said, I also own smaller ones. This one is fairly large at around 152cm. It's advantages is that if you have the space, it's a larger light source than a smaller one and because of it's convertibility they also work great for shoot groups.

Having purchased enough equipment over time, I will remind one that you do get what you pay for. I own cheaper umbrellas that have bent or broke when the wind kicked up (obv outside).

Here is some good data on umbrellas. And yep I own the one he talks about here too: http://strobist. blogspot. com/2006/03/lighting-101-umbrellas.html (remove spacing)