f2.8 vs f4 with today's high ISO cameras?

[seekinglight]

What are you going to be photographing? I own the 70-200mm f4L to photograph Cross Country and Track and Field. Plenty of light outdoors and because I can get close to the action I can still get shallow depth of field.

I would not consider f4 for indoor sports. In indoor sports where I'm often shooting at 1600 ISO and 1/640 sec at f2.0 or even f1.4 I consider f2.8 too slow.

I consider f2.8 to be too slow for indoor sports. If I had a higher ISO camera I would enjoy lower noise ISO 1600 shots, not go to higher ISO with slower lenses to get the same amount of noise. I have considered that the new cameras might make the 70-200 f2.8 more usable for indoor sports.

 

[manaheim]

I missed that they were both L lenses. Sorry.

 

[c.cloudwalker]

L does not always mean much. Although an L zoom will most probably be better than a non-L zoom, it may not be better than an non-L prime.

 

[inTempus]

L does not always mean much. Although an L zoom will most probably be better than a non-L zoom, it may not be better than an non-L prime.

I agree, I've compared the F/1.4 50mm to the f/1.2L 50mm and I swear you couldn't tell any difference in the IQ when eyeballing the images side-by-side.

I've found the same to be true of the f/1.8 85mm vs. the f/1.2L 85mm. I actually think the 85 f/1.8 is a better all around lens. I've often considered selling my 85L and replacing it with the faster focusing non-L version, then taking the difference and buying yet another lens.

 

[MrLogic]

I've found the same to be true of the f/1.8 85mm vs. the f/1.2L 85mm. I actually think the 85 f/1.8 is a better all around lens.

This is what the great Ken Rockwell has to say about these lenses:



[FONT=Arial, Helvetica, sans-serif]"This Canon 85mm f/1.8 is very good. It's more resistant to ghosts and flare than the Canon 85mm f/1.2L II.[/FONT]

and:

[FONT=Arial, Helvetica, sans-serif]"The Canon EF 85mm f/1.8 USM is an easy lens to recommend. It's much better than you expect, so if you're reading this because you think you want one, then just go get one. You'll love it![/FONT]
[FONT=Arial, Helvetica, sans-serif]
[/FONT]​

[FONT=Arial, Helvetica, sans-serif]The only things the five-times as expensive Canon 85mm f/1.2L II does better is lighten your wallet, fatten the weight hanging around your neck and it's a little sharper in the far corners, full frame, wide open.[/FONT]
[FONT=Arial, Helvetica, sans-serif]
[/FONT]​

[FONT=Arial, Helvetica, sans-serif]The f/1.8 focuses much faster and easier, and is an all-around more satisfying lens than the f/1.2. The f/1.2 is for weird things like astronomy where you absolutely, positively need f/1.2."[/FONT]​

Canon 85mm f/1.8

 

[inTempus]

OMG, please delete your post. That's not nice. I can't have that dolt agreeing with me.

 

[robertwsimpson]

85mm f1.8 vs 85mm f1.2 @ f/1.8

is it just me or is the L lens much sharper at f/1.8 than the other lens? I don't think they're even until about f/4

maybe in practice it's less pronounced, but there is a definite difference.

 

[inTempus]

I'm sure there is a difference, but the question becomes is there a noticeable difference in real world pictures and is that difference worth $1400.

The 1.8 looks better in some respects than the 1.2, and in other respects the 1.2 looks better than the 1.8 in the linked to test IMHO.

 

[robertwsimpson]

how? I mean, I get the whole "is it worth the extra $1400?" argument, which I don't think so, but I see more vignetting and less sharpness and contrast in the 1.8 in every interval. Like I said, when it gets to f/4, they look pretty much exactly the same. I was surprised to see the amount of CA on the f1.2 when shot wide open. the black looks purple.

 

[c.cloudwalker]

L does not always mean much. Although an L zoom will most probably be better than a non-L zoom, it may not be better than an non-L prime.

I agree, I've compared the F/1.4 50mm to the f/1.2L 50mm and I swear you couldn't tell any difference in the IQ when eyeballing the images side-by-side.

Wow, inTempus, you mean we can actually agree on something... WINK!

And believe me, if I had known I was saying something agreeing with Rockwell, I would have shut up. LOL.

Seriously, as you say in your later post, there is a difference between lab tests and everyday reality. And personally I can't care about lab tests if it passes the other test.

For those who don't know me, I can only repeat that I worked for about 12 years in PJ with no pro equipment. No magazine or newspaper editor ever asked me what equipment I was using. Even when they were buying my photos rather then using their man-in-the-field's work...

 

[Derrel]

how? I mean, I get the whole "is it worth the extra $1400?" argument, which I don't think so, but I see more vignetting and less sharpness and contrast in the 1.8 in every interval. Like I said, when it gets to f/4, they look pretty much exactly the same. I was surprised to see the amount of CA on the f1.2 when shot wide open. the black looks purple.

Robert,
Yes, the black looks purple--that's chromatic aberration, which is something the 85/1.2-L suffers from pretty severely at wide apertures. It also has a green chromatic aberration as well; one color in front of the point of sharpest focus, the other color behind the point of sharpest focus--but that does not show up on a flat test chart! That purple AND green CA is now often called bokeh chromatic aberration, but the proper term is longitudinal chromatic aberration, and longitudinal CA is VERY hard to eliminate in post--as in basically impossible to eliminate; lateral chromatic aberration, ie color "fringing" is easy to eliminate, and the better new Nikon cameras know the lens by CPU EXIF exchange information,and those cameras can "map out" lateral CA from all the Nikon lenses entered into the camera profile. I suspect Canon will be introducing this same feature pretty soon on in-camera created JPEG images. It's a software thing,and it would be easily done, if it became a design priority,and it might, in time.

Anyway...yes, there is plenty of purple CA shown, and the L lens does resolve better on the test chart--BUT, in real world shooting of many subjects, CA is not as visible as it is on these test charts. As far as CA goes, a good comparison would be between the Sigma 50mm f/1.4 and the Canon 50/1.2-L; the Sigma is targeted directly AT the CANON...Sigma deliberately went after one of Canon's most highly desired lenses, and priced their lens $1,000 lower, with higher resolution and lower CA. Of course, it's a Sigma and not a Canon-L lens so for some people that makes a difference. A lot of people are purchasing lenses based on test chart and pixel-peeping, and also on status value and marketing practices; the "status" value of f/2.8 appeals to many people, as does the L-designation. Worth,price,and value are all separate things, but many people intertwine or confuse them.

What does this have to do with the OP's question? Well, looking at the Chart linked to above, the differences on the 1Ds-III at 22 MP are more pronounced than on the 1Ds-II at 16.7 MP. I think a few things are relevant here: there IS A WAY to map-out lateral chromatic aberration on in-camera JPEG images and also on RAW images, and Canon will probably work on that in the future. Also, the differences between the 1.8 and the 1.2 and the 2.8 and f/4 70-200 lenses is reasonably small,and on BigTwinkie's current camera, the difference is probably very,very slight. On a 10-12 MP sensor, especially a FF model, any lens looks good; as we go forward to the higher and higher and higher MP count sensors, like 17MP on 1.6x ie 7D, lens quality and lens characteristics become a bigger problem,and better lenses are needed. And finally, these lenses last a LONG time. In amateur use, I'd expect most Canon L lenses to last 30 years. These L-grade Canon;s are built like TANKS! These lenses will last two decades or more.

The 70-200mm f/4-L IS is the NEWEST of the Canon 70-200's; as such, it has the best design Canon could come up with for the price point. I think it is worth every penny of the asking price--the 2.8 IS model that I own is known to be weak at the longer focal lengths, and I think Canon corrected for that in the design of the newer f/4 model. Lenses have their own signatures, their own problems, and the test charts show those, but real pictures show what the lens can do. I think it really come down to, "Will I pack it, or leave it home?" ie--is the size/weight so high it'll ride on the camera, or sit at home? Most of the modern lenses now are pretty good. A few are great. Worth, price, and value; the 70-200 f/4 L-IS USM...it's got all three bases covered. What's it worth to have a small,light, pro-grade lens?