While the suretele
While the suretele
first off: I always love the high quality answers I get here. thank you all for that.
rich, I have the 70-200 f2.8 LII IS as well - is the 24-70 as fast? (that would be great imho.)
jan and wickerprints, I appreciate your advice on the bodies. not sure if my immediate budget will allow for an upgrade but it finally explains to me why I should invest in those bodies when up until now the 7D seemed fine to me. (image size didn
Originally Posted by Jan Paalman
<span style="font-size: 10px;"]<span style="font-size: small;"]As far as pre-focusing I was referring to the very slow and delectable 85mm f/1.2L.
<span style="font-size: 10px;"]<span style="font-size: small;"]I agree that it would be tough to prefocus on a plane in flight with the 100-400mm f/4.5-5.6L, since you don't know where it's going and where it will end up in order to prefocus on a pre-determined distance point. I don't own this lens so I don't know how fast or slow it is. I would guess that it is on the slow side since it's a variable aperture zoom and f/5.6 @ 400mm. I certainly think it's a great zoom range for an Air Show. As HDNitehawk has mentioned, the super-telephotos have a nice pre-focus ring that is useful if you know what your pre-focus distance will be.
<span style="font-size: small;"]The 100mmL Macro IS focuses just as fast as any other 2.8 lens that I have. The key to the fast AF is to make sure that you don't manually rack the focus ring into the macro range. If you look on the barrel of the lens, make sure that you "don't start within the yellow markings on the barrel between 1:1 or 1:5", what you want to do is start with the white markings on the barrel at 1M, as Wickerprints has suggested, if you do that when you start shooting sports then this lens can AF just as fast as the other f/2.8's mentioned in this thread. If you accidentally, manually go into the macro range then you are no longer using it as a standard 100mm lens so all bets are off and you won't be able to AF on far objects. <span><span style="font-size: small;"]Also make sure that the distance limiter switch on the barrel is selected to the appropriate distance.<span><span style="font-size: small;"]
<span style="font-size: small;"]The same rule applies for the 24-70mm f/2.8L macro, however the non-macro range starts at 0.7m on the lens barrel. This lens however can seem to get itself out of macro mode much easier than the true macro 100mm f/2.8L IS.
<span style="font-size: small;"]Since I don't own the older model of the 100mm f/2.8 macro, I will refer you to Bryan's review;
http://www.the-digital-picture.com/Reviews/Canon-EF-100mm-f-2.8-USM-Macro-Lens-Review.aspx
<span style="font-size: small;"]Bryan's Quote:
<span style="font-size: 10px;"]<span style="font-size: small;"]"Utilizing USM (Ultrasonic Motor), the Canon 100 Macro internally<span style="font-size: small;"]focuses very fast<span style="font-size: small;"],<span style="font-size: small;"]quietly<span style="font-size: small;"]and<span style="font-size: small;"]very accurately<span style="font-size: small;"]. I've been questioned on the fast AF statement several times since writing this review. I've rechecked my lens and, though it takes a little time to go from 1:1 macro to infinity, it focuses very fast at normal focusing distances. The second person to question this exchanged their lens for another - the replacement was much faster than the original lens they received. This would indicate to me that there may be an issue with some samples of the Canon EF 100mm f/2.8 USM Macro Lens. Another site visitor emailed me - they were ecstatic that a firmware upgrade to theirCanon EOS 1D Mark III DSLR[/i]<span style="font-size: small;"]resolved their 100mm Macro focusing speed issue. Also note that there is a discontinued non-USM version of this lens. Keep these datapoints in mind if you run into a slow version of this lens."
<span style="font-size: small;"]I suspect the discrepancy in AF speed regarding this 100mm Macro lens may have to due with people accidentally or unknowingly wandering into the Macro range, where it will be as slow as a turtle. Anyone who owns this lens should give it a try, and then they'll understand the discrepancies from Macro AF Speed, to Normal Range Fast AF speed. Their also may be other explanations as Bryan has alluded to; such as an older non-USM version, a bad copy, or out of date firmware.
<span style="font-size: small;"]
Rich
Originally Posted by memostothefuture
<span style="font-size: 10px;"]<span style="font-size: small;"]Memos to the future..., <span style="font-size: small;"]It's our pleasure!
<span style="font-size: small;"]
<span style="font-size: small;"]I just tested the 24-70mm f/2.8L macro and compared it's AF speed to the 70-200mm f/2.8L IS II. I used my 7D in one shot<span style="font-size: small;"]so I could hear the "beep and be more aware when AF lock was achieved.
<span style="font-size: small;"]<span style="font-size: small;"]I can't really tell much of a diifference in AF speed, maybe the 24-70mm f/2.8L feels a little faster due to it's shorter focal length.
<span style="font-size: small;"]As a reference, I also compared both to a 135mm f/2L and they all seemed very fast. If I had to choose a winner, I would give the nod to the 135mm f/2L, not surprising because it's a prime and f/2.
<span style="font-size: small;"]They all appear to be "very fast and instantaneous" to me.
<span style="font-size: small;"]I also tried them all in AI Servo and they all felt very fast.
<span style="font-size: small;"]Just be aware, as mentioned above that the 24-70mm f/2.8L Macro, has a macro range that you should stay out of.
<span style="font-size: small;"]I hope that helps,
<span style="font-size: small;"]Rich
You guys also forgot the 35mm f/1.4 L.