[bran6209]

...f/2.8 or 35mm f/2?

[dodol]

This is not a real lens specifications. I think you only specify the first lens on the wide end of the lens which will give us nothing to help you.Except if you mean 28mm f1.8 and 35mm f2... they are both very sharp. The only thing you should choose is whether the focal length fits your profile or not.

[dotsnail]

The F/2.8 aperture on a 28mm lens is pretty common. A 35 mm/f2 lets more light in and may be a bit more expensive. Both lenses will be fine. Typically, you want to stop down the lens a bit because they have some small flaws at full aperture. In low light situations a larger lens opening will make hand-help shots possible.Your choice should be guided by what angle you need. 35 mm is only mildly wide-angle (on 35 mm film) while 28 mm starts to be wide angle.The fixed focus (prime) lenses are sharper and have a wider lens opening than zoom lenses. It is exceptionally difficult to make good zoom lenses that go to a really wide angle (unless you spend over $1000). So enjoy your wide angle lens.

[Petra_au]

Both are quite old prime lenses, which lack USM (ultra sonic motor) but from the reviews below, I'd say the EF 35mm f/2 is a little better than the EF 28mm f/2.8.If you want a very good wide angle lens, have a look at the EF-S 10-22mm f/3.4-4.5 USM, if you have a 1.6X crop factor dSLR.Another very good prime lens is the EF 50mm f/1.4 USM. It's more of an 80mm (1.6X crop factor equivalent) and makes an excellent portrait lens.

[TheCat]

I would consider EF-S 17-55mm f/2.8 IS. This is known as the sharpest standard zoom lens and it has image stabilization too.