« on: September 26, 2012, 09:39:20 AM »
My copy of the 70-300L is very very sharp at 70mm till about 135-ish even on the 5D3. I start noticing the edge softness above 200mm even at f8-f11. The center frame sharpness is identical for both bodies. For your application at 300/5.6 the edges would be blurred anyway.
If you're not looking at the 24-70 for shallow depth of field and mainly just for low light, I think the 17-55 on 60D with IS is better. I'm not very stable so the slowest I can handhold is 1/100 even at 24mm so I really miss the image stabilization from the Sigma lens. After I acquired the 24-70L, I found out that Tamron makes a good 24-70 f2.8 with IS, it's too late for me but you might give it a consideration.
Yeah, I looked at most of my shots from 200-300mm and (with a few exceptions) they are all attempting to isolate subjects from the background. So the edges are OOF anyway.
As for the 24-70, I currently use the 17-55 for wide perspective at social events (group shots, portraits from short length, candids) and where I find IS to come in most handy is when the lighting is dim and I'm forced to use a flash. Normally with regular shutter speeds the background comes out dark, but I can take advantage of IS to use much lower shutter speeds and try to get more of the background lit. I notice the colors come out richer when I do that as well. That is one perspective I will miss (unless there is another way to achieve this)...otherwise for most event shots I have to shoot 1/80 anyway or the person moves enough to become blurry.
I haven't tested the 35L but if you like the 35/1.4 on the crop sensor, you'll definitely like it on full frame. I recently shot a charity event with the 24-70 mostly at that focal length and at 70mm. It is wide but not too wide as to cause distortion. You can really get close to your subject while also including some of the environment. I also have the 50/1.4 which I rarely used on the 60D because it's too narrow for most things and not as sharp as the 70-200II for portraiture. I use it a lot more now on the 5D3 because of it's size and weight and low light ability. The depth of field seems better too on the 5D3, it's smoother. It's almost useless at f1.4 though. I don't know why you would need an f1.2. I personally rarely use my lenses wide open. I prefer the look of f4-f5.6 for sharper portraits and just blur the background and I prefer to raise my ISO for low light. I'd rather have grainy photos than blurry/ out of focus ones, but I'm still learning, I've only been shooting for about a year so that might change.
Isn't this a similar perspective to 24mm on the crop? Perhaps I'll look through my event photos and see how many I take at ~22-24mm setting. Often I tend to stick mostly to the ends (17mm good for group shots as long as folks aren't at the edge of the frame; 55mm good for head shots at close range). But the main appeal of the 35 1.4 is that it's the only ultra-fast lens in my collection. All others are 2.8 or slower. Without flash, I can shoot even in the darkest of places with it (color balance is another issue altogether, but shot is better than no shot). That is why I mentioned the 1.2 (I know the 1.4 is there, but I didn't like it even on a 1.6x camera due to softness and fringing at 1.4-2.8 )...but we'll see. Most sites seem to be unimpressed by it given its price premium, and I look at a few sample shots and wasn't astonished (although they were landscape shots in daylight, that wouldn't be my use for a lens like this)