# 20mm f/2.8 vs. 28mm f/1.8



## grey4 (Jul 17, 2012)

I'm having a hard time deciding between these two wide angle primes. I have a 7d and i'm going to acquire a 5d mark ii soon. I feel as if we can debate wider/slower versus tighter/faster. They're also about the same price. But my question is regarding optical quality. Would anyone know if one of these lenses is significantly better in terms of sharpness, CA, and the sort? If it's a tie, I think i'll pick the 20mm f/2.8


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## bdunbar79 (Jul 17, 2012)

Free literature:

http://www.the-digital-picture.com/Reviews/Canon-EF-20mm-f-2.8-USM-Lens-Review.aspx

http://www.the-digital-picture.com/Reviews/Canon-EF-28mm-f-1.8-USM-Lens-Review.aspx

Take the reviews with a grain of salt: this is a pro review. I have heard that the 28 performs better, both perform better on crop vs. FF, but they take pictures that are good enough. Look around on flickr as they have pages devoted to specific lenses.


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## Videoshooter (Jul 17, 2012)

I'm in a similar position to you - I have a 60D and am looking to upgrade to a 5dmkII, and want a fast, wide prime. I think I'll go with the 28mm 1.8 for the extra speed - I feel the the 20mm 2.8 is too close to a regular zoom lens (eg my current 17-50 2.8, or a 24-70 2.8 when I upgrade to FF), whereas the 28mm 1.8 will actually add something that is not available with other lenses. 

Plus while I'm waiting to go FF it will work as a nice 50mm-ish equivelant on APS-C, as I currently find my 50mm 1.4 a bit long to handhold in dim light or when shooting video.


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## CharlieB (Jul 29, 2012)

I've got both. I've shot the 20mm since film days on a pair of EOS5's

Here's what you'll find.

Both have falloff that is considerable wide open, even on a 1.6 crop. The 20 is worse.

On a 5d2, the peripheral adjustment almost corrects that fall off 100 percent. Think in terms of 95+ percent, bare bare perception of falloff, either lens.

Stop down either lens one stop, and fall off is greatly reduced. If you shoot either stopped down more than a stop, you'll not even notice any falloff, except on bare flat surfaces shot straight on. Its a non-issue for the vast majority of shooting, if you close the lens more than a stop from wide open.

Both show a little flare, but its not bad. The only wide lens that I own that does not show ANY flare, is the 28/2.0 Summicron Aspheric... but its $2000 more than either of those lenses. Wides tend to have a little flare, neither of these are bad.

Sharpness - both are a little soft in the corners wide open, and sharpen up nicely with two stops stop down on FF or a stop down on 1.6 crop. Centers are very sharp. Contrast is excellent in the center, and like sharpness, a little stop down makes it excellent. Color rendition is the same. CA doesn't bother me in my shooting, but... both have a little residual CA, the 28/1.8 worse in that regard but not terrible.

Honestly, they're lenses that work like we'd expect them too. Relatively fast optics, showing typical wide open edge softness, that clears up well with a little stopping down. 

My overall opinion - they're not punchy like Leica current Leica lenses, but... they're decently good lenses, either one. Choose by your focal needs. I liked both on a 1.6 crop - the 28 shot sort of like 50, and the 20 shot sort of like a 35 (my favorite focal length). Both are ok in low light, with the 28 a bit faster, naturally.


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## mathino (Jul 29, 2012)

So here we go, all shots using 450D and 28 f/1.8 at ISO 1600 and at f/2. No adjustments made, just sharpness at 3 in camera, conversion to JPEG via DPP.

https://picasaweb.google.com/118404355708350245990/Cats


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## wickidwombat (Jul 31, 2012)

That's a lot of pussy


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## mathino (Aug 2, 2012)

wickidwombat said:


> That's a lot of pussy



Well, all photos shot at cat show here in Bratislava - thats why so many cats  I can post more samples taken with 28 f/1.8 USM but they are on my extrenal HDD and I had to dig them out. Maybe in the evening Ill find some time to check them a post.


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## Wideopen (Aug 7, 2012)

wickidwombat said:


> That's a lot of pussy



Lol agreed


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## wickidwombat (Aug 7, 2012)

If you are considering a 20mm prime have a good look at the voigtlander 20mm f3.5 color skopar SLII I am loving mine its so awesome and a great pancake partner for my 40mm


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