70-200L f/2.8 vs 70-200L f/4: The battle @ f/4

100% crops.
Both lenses on 5D mark II, 200mm, manual focus on "15", tripod, MLU, default LR 2.6 sharpening.
The f/2.8 has been rotated a few degrees to match the f/4.

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still inconclusive because you had to rotate the 2.8... rotation can degrade the photo... lol

personally... none of this even matters lol... if you need the 2.8 get the 2.8 if you dont.. get the f4 lol simple choice.

70-200L f/4 IS owners will be in here shortly to discredit your test...

canonnoob wrote in post #9247266
still inconclusive because you had to rotate the 2.8... rotation can degrade the photo... lol

Honestly I cannot see the difference between the rotated photo and the original in these 100% crops: test is valid !

Megapixle wrote in post #9247277
70-200L f/4 IS owners will be in here shortly to discredit your test...

LOL

Well , what I can pick on is: slightly more contrast in the shot from f4. Slightly more CA from the f2.8 @ extreme bright coloured edges and a little better sharpness (marginal!) from the f4 but that's just being picky.

MHO wrote in post #9247306
Well , what I can pick on is: slightly more contrast in the shot from f4. [...]

Actually I prefer the lower contrast on the 2.8 due to less digital noise and better shadows. I usually increase contrast - if needed - in PP.
The 5D2 has ugly digital noise patterns.

I see a very slightly sharper shot from the f/2.8. Theres more contrast and a slight difference in exposure which disguises it a little.

I don't have the IS version, because acording to lab tests at the time I was buying the non IS f/2.8 is very slightly better than it's younger brother. In the real world it makes no difference which of the three you use.

Try a similar test; versatility, about shooting fast moving action indoors under marginal light.

If your primary use for the 70-200 would be outdoor events for kids, when would you need the f/2.8 over the f/4? Strictly a dusk and dawn issue?

rijndael wrote in post #9250974
If your primary use for the 70-200 would be outdoor events for kids, when would you need the f/2.8 over the f/4? Strictly a dusk and dawn issue?

yes, dusk and dawn issue because of the low lighting, but not strictly. you can also use f/2.8 over f/4 when you want narrower DOF as well. And, also if you feel like working your arm a little too.

Thanks. I'm trying to decide between the two. I'm not overly concerned about the price of the f/2.8 if I can justify the need for f/2.8 over f/4 ..... I'm not convinced yet.

hmmm weird, 2.8 looks better to me here. F4 looks to be suffering a bit CA.

Maybe I'm just missing something here. I don't see really what this test proves, or disproves. One lens is stopped down, the other wide open. Either compare them both wide open, or both stopped down. To me, debating the sharpness of the 70-200 L's is kind of like debating the sharpness of Bic razors vs Gillette razors, they're all sharp.

canonnoob wrote in post #9247266
still inconclusive because you had to rotate the 2.8... rotation can degrade the photo... lol

personally... none of this even matters lol... if you need the 2.8 get the 2.8 if you dont.. get the f4 lol simple choice.

your statement doesnt make sense. where did u learn that ?

zshaft wrote in post #9251615
your statement doesnt make sense. where did u learn that ?

you referring to the degradation portion? do a quick google search for "photo rotation degradation photoshop" or something similar...you'll see that this can, and does, degrade the photo...

if you're referring to his overuse of LOL, then i can't help ya there...