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SportsShooter.com: Member Message Board

Canon EF 70-200/2.8 focus issues -- HOW to FOCUS A ZOOM LENS
Cory Lum, Photographer
Honolulu | HI | US | Posted: 3:42 AM on 11.02.08
->> greetings ss members

has anyone used a new CANON EF 70-200/2.8L lens and had focus issues. maybe its pilot error. i usually zoom to 200mm focus critically, then go to 100 or 150mm for composition and get sharp results. i got a new 70-200/2.8L and the focus shifts. giving me out of focus pics. comments ? suggestions ?

when using my 16-35mm i do the same for critical focus. first i zoom to 35mm then i go to the 16mm focal length. i always have sharp pics this way.

thanks !
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Stew Milne, Photographer
Providence | RI | USA | Posted: 9:11 AM on 11.02.08
->> I've noticed this too. If you focus at 200mm, then zoom out and hit the autofocus button, the camera/lens refocuses. I may be wrong, and please correct if so, but I think it has something to do with the digital bodies.

When I used film, this is the method I used to focus, with perfect sharp results. But with DSLR, the focus doesn't stay when you zoom out.

-sM
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Michael P. King, Photographer
Appleton | WI | USA | Posted: 9:23 AM on 11.02.08
->> Thanks for bringing this up Cory,

I have to agree with you. I notice this with my two IS specimens (one work, one personal). And for the record, I've never been very happy with the overall sharpness of the 70-200 lens.

Like you say, it could be user error... I'd love to hear what people think about this.
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Nik Habicht, Photographer
Levittown | PA | USA | Posted: 9:39 AM on 11.02.08
->> There have always been two ways to build zoom lenses --- way one allows you to focus and then change the amount of zoom while the image remains in focus --- these are harder and more expensive to build. Way two is to have the lens not hold focus as you zoom it --- cheaper and easier to build. In this day of AF cameras, I wouldn't be surprised if more manufacturers were going to go the second route....
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Daniel Bates, Photographer
Fayetteville | NC | | Posted: 10:24 AM on 11.02.08
->> I use back button focus and the zoom-in technique. It worked with my 70-200 non-IS. The trick is separating the act of focusing from the act of taking the picture.
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Stew Milne, Photographer
Providence | RI | USA | Posted: 10:33 AM on 11.02.08
->> Daniel, I have always used back focus, and have always had this problem. It's not a focusing issued related to having the AF linked to the shutter button.
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Jeff Mills, Photographer, Photo Editor
Columbus | OH | USA | Posted: 12:04 PM on 11.02.08
->> I've always belived the 70-200 was in fact a parafocal lens but perhaps thats not the case. If you focus it at 100mm and zoom to 200mm and take the shot, as well as at 100mm and then zoom into 200mm and take the shot, are the results both out of focus ? Perhaps its just parafocal if you zoom in more ?

How critical of testing are you talking about ? In actual shooting with mine, I never had any issues of the lens not being parafocal, however, that was only under typical shooting conditions where the larger DOF could of covered any errors. I never tried or tested it under controled conditions. I could always shoot a group shoot at 100mm and then zoom into a tigher shot at 200mm with no problems though.

Personally for critical focus, I've always found that its best to focus at the actual focal length you'll be shooting. There really aren't that many parafocal lenses made so its typically nessacary. I used to always use an angle finder C with the 2.5x mag, or later, the zoomed in LCD view of liveview on the DIII
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Cory Lum, Photographer
Honolulu | HI | US | Posted: 12:07 PM on 11.02.08
->> i have a mark IIn, 5D and even my 10D, it works with my older EF70-200/2.8 by focusing at 200mm and then zooming to 100 or 70mm. the odd thing, the new 70-200/2.8L i just received has this problem. so its not just w/ film bodies. and i always use custom function 4, back focus. i've always used my zooms w/ digital this way, by going to max focal length, then zooming out to the wide focal length for critical focus and have never had a problem, even w/ my old canon 10D. i'd like to hear from more people on this.
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Tom Knier, Photographer
Lancaster | PA | USA | Posted: 12:12 PM on 11.02.08
->> Cory, your method only works so long as your lens' back focus is accurately set in the factory. My Nikon 80-200 holds it- but it's slightly fuzzy. I need to re-focus after I recompose a shot.

Broadcast video lenses have adjustable back focus (technically, focal flange length)- meaning, if you focus, zoom, and it's no longer in focus, you can adjust it so it remains focused throughout the zoom range...

Here's the best explanation I can find online as far as video lenses go:
http://www.mediacollege.com/video/camera/focus/back-focus.html
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Josh Merwin, Photographer
New york | NY | USA | Posted: 1:37 PM on 11.02.08
->> The Canon 70-200 lenses are the worst focusing lenses I have ever used. I have had several versions of both the IS and non IS lenses and shooting action it was basically pot luck on whether or not the shot would be in focus, especially when shooting in a burst. I would say that I don't know how a company could produce a lens that doesn't function well, but just look at the Mark III and its issues...
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Andrew Nelles, Photographer
Levittown | PA | usa | Posted: 1:46 PM on 11.02.08
->> Oddly my 70-200 non-IS is one of my few Canon zooms that does not have this issue. My 16-35 and 24-70 both have focus shift from zooming out, although slight, the 70-200 is dead on.

I love my copy of the 70-200, next to my 85 1.8 I feel it's the sharpest lens I own, keeping me from upgrading to an IS copy. I guess I just got reallu lucky.
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Jeff Mills, Photographer, Photo Editor
Columbus | OH | USA | Posted: 1:53 PM on 11.02.08
->> Like Andrew I've never had a problem with a 70-200. I've had 2 copies of the IS version, one of the non IS and one of the non IS f4 version. Every one has been flawless. Great focus speed and no sharpness issues anywhere over the range. Hands down Canon's best zoom lens if you ask me.

Josh, have you had these issues all on the same body ? Sounds more likely you've got a body issue than the chance of getting several bad 70-200's in a row.

If your getting inconsistant results, especially in a burst, that sounds way more like a body issue than a lens issue.

I had 3 mkIII's and 2 of them defiantly were horrible in servo burst shots, one frame sharp, next two OOF, next one sharp etc. Lens worked fine, just horrible cameras
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Josh Merwin, Photographer
New york | NY | USA | Posted: 4:22 PM on 11.02.08
->> It was with several different cameras...I'm now shooting Nikon. I don't have to worry about cameras that don't focus anymore
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Greg Ferguson, Photographer
Scottsdale | Az | USA | Posted: 6:42 PM on 11.02.08
->> A couple things:

Autofocus bodies, especially PRO autofocus bodies coupled with pro-lenses, are plenty fast and accurate to track focus as you zoom, and should supply tack-sharp images assuming you've got good light and a subject that isn't monochromatic.

Parfocal lenses were great when we focused manually, but today's gear should be so accurate and fast that it's not an issue not having parfocal lenses. I keep the focus button mashed as I zoom. You have to have a pro-lens though as the consumer lenses seem to have a war between focus and zoom, with focus losing. More info about parfocal and the zoom-focus issues are on these pages...

http://en.wikipedia.org/wiki/Parfocal_lens
http://www.cheapshooter.com/2007/09/25/focusing-trick-can-lead-to-blurry-im.../

If a body and lens combo is suspiciously out-of-focus too often, then switch lenses with another body and see if the problem follows the lens or the body. If the problem goes away don't use that combo. If it follows one or the other, send it in for calibration, don't waste time hoping it will get better.

Dirt can affect the contacts between the lens and the body, as can moisture so make sure they're clean. Wipe them periodically with a microcloth.

Lenses get banged a lot and that can damage internal components and/or bend the mount at the body causing misfocus or bad electrical contact. Again, trying the lens and body swap will help diagnosis the problem. Another test is to mount the camera and lens on a tripod perpendicular to a wall with a newspaper taped to it. Photos taken should be sharp in the center and corners. If all corners are equally out-of-focus it might be a design problem in the lens. If one or two corners are not sharp the lens or camera mount might be damaged or the sensor might not be parallel to the focal plane of the body.
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Jeff Mills, Photographer, Photo Editor
Columbus | OH | USA | Posted: 9:23 PM on 11.02.08
->> Greg. you must of never used a Sigma 120-300 then LOL.
That lens, while having plenty of merits, proves for an awful battle between trying to focus while zooming out. I think the way its set up, zooming out changes the focus one direction and the camera is trying to focus on the advancing player the opposite direction so it gives tons of OOF shots. Really need to zoom, stop, then focus, which sort of defeats its main purpose.


Some bodies though, like the first two 1D mkIII's I had while "supposed" to work, sure didn't track well in the slighest.
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Chuck Liddy, Photographer
Durham | NC | USA | Posted: 12:48 AM on 11.03.08
->> ya know, I read threads like this and all I have to say is I think there are a lot of people out there who haven't a clue of what their doing.......or how their equipment works.
oh, and yes I'm VERY sure the good ole "inappropriate" button will be pushed for saying this. after all it is ME!
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Stew Milne, Photographer
Providence | RI | USA | Posted: 8:16 AM on 11.03.08
->> Chuck, are you referring to the fact that anyone with enough money can buy expensive camera equipment that does EVERYTHING for them. You just need to point the camera in a direction and push a button? Simple, right?

I'm sure there are many SS.com members who have no idea how their equipment works and don't care to know either. Do you have to know how it works before you use it? How many of us have never read the owners manual for their DSLR? There's an classified AD currently on SS.com that mentions "manuals still in original opened plastic wrap." Many of these questions are rhetorical.

I won't mark you (Chuck) "inappropriate" though. I enjoy your remarks, most of the time. ;)

"the only dumb question is the one not asked."
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Luke Trottier, Photographer
Bath | ME | US | Posted: 9:08 AM on 11.03.08
->> The 70-200 should focuses almost instantaneously on a 1 series body. If its not focusing correctly send it to CPS for repair.
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Chuck Liddy, Photographer
Durham | NC | USA | Posted: 10:19 AM on 11.03.08
->> stew, that was kind off my point. I used to NEVER read the manuals...back in the film days....and even the first digital
cameras we used were pretty easy..but now? I'mn not sure how many different function controls there are on a mark III. I read the manual the day I was issued the cameras because (well I was a nikon guy) I didn't have the faintest clue what I was doing. in fact I keep a manual in my computer bag all the time so I can refer to it if I have to. now a days that's the deal.
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Jeff Mills, Photographer, Photo Editor
Columbus | OH | USA | Posted: 1:11 PM on 11.03.08
->> Manuals are really a must read these days if you ask me, theres just so many layers of functions and controls that to get the most out of your camera, or even make it perform halfway decent, you need to fully understand how it works

Take my first 1D mkIII, I was rather frustrated with the inability to shoot ISO100. Couldnt figure out why it wouldn't go down that low and then I finally read in the manual that if you had that higher dynamic range mode or whatever it was called turned on, ISO200 was the lowest setting.

Since switching to Nikon I found the buffer to be rather small but read that its due to the active d-lighting and/or noise reduction turned on. Problem solved yet again.

Cameras have never been more complex and manuals never thicker or perhaps more boring to read, but trying to pick up a camera like a D3 or 1D mkIII and expecting to just figure it out on the fly probably isn't going to happen.

I've honestly still got my D3 manual in my bag because coming from Canon, I was clueless.

Just last week I had an assignment were I needed to create new folders for each group, and I had to take a few minutes, pull out the manual and read how to do it lol.
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Renay Johnson, Photographer, Assistant
San Diego | CA | | Posted: 2:05 PM on 11.03.08
->> I admit I am guilty of the "focusing "trick" of zooming to focus, then recompositioning before shooting. I guess it's a crapshoot on whether or not it works. As long as you to recompose too far away from your focusing point, they your okay.
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Eric Francis, Photographer
Omaha | NE | United States | Posted: 3:11 PM on 11.03.08
->> This is going to surprise you Chuck, but I'm with you and know what you're saying.
I don't understand why 'you' wouldn't just hit the focus button at the focal length your composition is.

Now, someone help Chuck up off the floor as I'm sure he fell from his chair after reading I agreed with him.... lol.
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Jeff Mills, Photographer, Photo Editor
Columbus | OH | USA | Posted: 3:36 PM on 11.03.08
->> Eric, I think the OP was talking about zooming and manually focusing (perhaps a 1D mkIII owner lol) which of course is easier to do the more zoomed in you are.

Personally I'm with you 99.9% of the time. Maybe I'm just rusty or need glasses, but the camera AF is more accurate than my MF skill in nearly any situation. (especially since I switched to Nikon and got a D3)
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Chuck Liddy, Photographer
Durham | NC | USA | Posted: 4:12 PM on 11.03.08
->> "code blue!! code blue!! bring the crash cart!!!" 8))
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Wesley R. Bush, Photographer
Nashville | TN | U.S. | Posted: 4:20 PM on 11.03.08
->> Chuck: you're being a jerk.

Cory: My 70-200 is doing the same thing after I dropped it (one of many times, but the latest is right when the problem began.) Prior to that, it focused perfectly after zooming back out. Now it seems as if the focus is always about one foot behind a person standing 10-12 feet away. I'll let you know when I get it back if it's fixed. I'm sending it in probably next week.
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Chuck Liddy, Photographer
Durham | NC | USA | Posted: 5:40 PM on 11.03.08
->> wes, sorry you're apparently humor impaired. at least when I state my opinion I don't resort to name calling. geez.
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Michael Zito, Photographer, Photo Editor
West Hills | CA | USA | Posted: 6:11 PM on 11.03.08
->> Back in the dark days when there were just manual focus cameras and lenses, (Stills and motion picture)the correct way to focus a zoom lens(as oppose to a variable focus lens) was to zoom in all the way to achieve most critical focus then zoom out to desired focal length. (If subjects moved, you would have to follow focus!)then shoot. You focused and then shot.
Stew, You said "If you focus at 200mm, then zoom out and hit the autofocus button, the camera/lens refocuses" Why would you focus twice? If you are going to zoom out and focus, no sense of zooming in to focus. If you have a stationary subject, zoom in, focus, Lock the focus then zoom out and shoot. Or put it on one shot, zoom in,focus zoom out and shoot.
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Greg Ferguson, Photographer
Scottsdale | Az | USA | Posted: 7:09 PM on 11.03.08
->> Some of the "zoom all the way in, focus, then zoom out" thinking is probably the result of using manual focus lenses. My old Minolta lenses worked better when I did that.

I held off from purchasing an autofocus system for a long time, then bought in when the D1x came out. I did a lot of tests to make sure it was able to out-focus my focusing abilities by manually focusing and then letting it take a whack at it, or by letting it focus then trying to tweak the focus to be better. It was at least as good as me and a lot faster 90% of the time - macro photography of nature was the usual place I'd win, especially if I was shooting through some plants.

Otherwise the technology is hard to beat, and second guessing it really doesn't pay off as far as I'm concerned. As said several times above, if you are seeing weird results odds are good something needs recalibration or fixing, because it should be tack-sharp. The only times it isn't is when the camera just doesn't have enough light to focus or no patterns or contrast to find edges.

As far as using Sigma lenses, the only ones I used were with my Minolta X-500. As far as using lenses that fought when I tried to zoom and focus, I've used several but they were not pro glass. The consumer Canon lenses feel like they're jamming up - my wife's 80-300 f4-5.6 zoom is a great example. She can't track focus and zoom because the images are all soft. Give it a chance to focus after the zoom has been set and it's tack-sharp.

The same thing was true of one of my Nikon lenses, I think it was a 100-400 f4-5.6. It sounded hellacious like it was spitting out gears when I'd zoom and focus. If I didn't zoom it'd focus reliably. Their pro 70-200 was just as nice as Canon's; Both were smooth and focused and zoomed reliably, but those are pro lenses and the others were consumer grade.

You better have the gear to get the job done and it has to be trustworthy because you very seldom get a second chance. We buy the expensive gear because it works even when we've treated it like inexpensive gear. :-)

In the rodeo arena I have about three seconds to get a shot of a bronc and rider before I need to look for safety. I shoot as I run backwards and can't stop, zoom, focus, rezoom and refocus unless I want hoof prints on my body.
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Cory Lum, Photographer
Honolulu | HI | US | Posted: 2:12 AM on 11.13.08
->> well

i got a replacement

its better.

but still off...
compared to my zoom i got.

shall i shuck my whole canon system in favor of the 'greener grass' ?

aloha
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Cory Lum, Photographer
Honolulu | HI | US | Posted: 12:28 AM on 11.23.08
->> update.

i got a brand new replacement.
the second lens is also not focusing properly.

i need to return and get a third replacement.

i tested my friends lens and it works, so its not the body.
wondering why canon factory is so sloppy and sending out defective lenses.
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Clark Brooks, Photo Editor, Photographer
Urbana | IL | USA | Posted: 8:53 AM on 11.23.08
->> One question....

"i usually zoom to 200mm focus critically, then go to 100 or 150mm for composition and get sharp results. i got a new 70-200/2.8L and the focus shifts. giving me out of focus pics."

When shooting like this are you hand holding the camera and lens?
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Eric Francis, Photographer
Omaha | NE | United States | Posted: 9:41 AM on 11.23.08
->> Cory,

Maybe it'd be easier at this point to adjust your shooting style.
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Stew Milne, Photographer
Providence | RI | USA | Posted: 11:31 AM on 11.23.08
->> Hey Michael: I would not normally refocus after zooming in to focus, but I was just testing the lens to see if it WOULD refocus. If it did refocus, it meant that the subject was no longer in focus after zooming out.

You can also test this w/o the camera doing the AF. You set the lens to MF, zoom in, focus then zoom out. When you you the back button focus after you've zoomed out the little green dot in the viewfinder will tell you if your subject is still in focus. Typically it is NOT.

-s
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Marc F. Henning, Photographer
Bentonville | AR | USA | Posted: 12:35 PM on 11.23.08
->> my Canon 70-200 f2.8 non-IS is my workhorse lens and is always sharp and is arguably the most reliable zoom lens, or any lens, in the Canon arsenal. i agree with Chuck 100% on this one. you've got to know how to use the gear correctly. i'm on my second 70-200 f2.8 now. i bought a new one last year. not because my old one had failed me, i just wanted to get a new one since my old lens had about 10 years on it...with no issues whatsoever.

as far as the Nikon equivalent. the Nikon 70-200 f2.8 VR is the biggest piece of crap i have ever attempted to shoot with. we have five of them in our pool at work and not one of them will yield consistent images when shooting sports. i've fallen back to an old 80-200 f2.8 just to get the job done. no problem with the old zoom. works great. i love it. the other sports shooters on my staff switched back to their 80-200's a long time ago. that Nikon 70-200 is nothing more than an overpriced paperweight i tell you.

marc
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Israel Shirk, Photographer, Assistant
McCall | ID | US | Posted: 2:24 PM on 11.23.08
->> Cory-
It's not the lens. It's not made to be used in that manner - it's not parfocal (though it is close). My 70-200 f/2.8L's (IS and non-IS) are the same way.

Parfocal lenses allow you to zoom after focusing; non-parfocal lenses need to be focused during and after zooming.

The 16-35 does the exact same thing, only it's a lot more subtle.

It's just going to require you changing shooting style - you have to focus while or after zooming. If you need to check critical focus/don't trust AF, use live view or check it afterwards. A manual focus grid might help if that's what you're trying to do.
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Adam Hemphill, Student/Intern, Photographer
Willimantic | CT | | Posted: 10:17 PM on 11.23.08
->> Despite easily found claims to the contrary, Israel is absolutely correct in his assessment that Canon's EF 70-200mm f/2.8 L (IS) USM is not a parfocal lens. The user manual states this (though perhaps not explicitly) when it advises that refocusing may be necessary after a change of focal length. While some have said that their copy of the 70-200 behaves consistently like a parfocal lens would, this is due to coincidence rather than design.
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Cory Lum, Photographer
Honolulu | HI | US | Posted: 3:29 PM on 01.14.09
->> i just tested an older 70-200/2.8 . seems it works like a parfocal lens. is this coincidence ?

tested my colleagues 70-200/2.8 IS and it works perfectly ( parfocal )
i focused at 200mm and then zoomed out to 70mm. tack sharp.

any more thoughts on this ?

my nikon 80-200/2.8 AFS works like a parfocal and focuses dead on.

thanks again for your thoughts on this

c
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Cory Lum, Photographer
Honolulu | HI | US | Posted: 3:55 PM on 01.14.09
->> list of parfocal lenses . from Chuck Westfall

EF 16-35mm f/2.8L USM
EF 17-40mm f/4L USM
EF 24-70mm f/2.8L USM
EF 70-200mm f/2.8L USM
EF 70-200mm f/2.8L IS USM
EF 70-200mm f/4L USM
EF 75-300mm f/4-5.6 IS USM
EF 75-300mm f/4-5.6 III USM
EF 75-300mm f/4-5.6 III
EF 90-300mm f/4.5-5.6 USM
EF 90-300mm f/4.5-5.6
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Steven E. Frischling, Photographer
Live HVN : Work SFO-NYC | | | Posted: 4:58 PM on 01.14.09
->> I had no idea my lenses came with a manual.

Maybe because I avoided using auto-focus (even with AF bodies and lenses) until late 2002 when I switched from Nikon to Canon) there was no need for a manual.

Pop the lens on and shoot.


Holy crap, now I feel like Chuck. Why do my knees suddenly hurt and I feel the urge to complain about a crick in my back......
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Dave Amorde, Photographer
Lake Forest | CA | USA | Posted: 6:05 PM on 01.14.09
->> "There's an (sic) classified AD currently on SS.com that mentions 'manuals still in original opened plastic wrap.'"

Stew, I do sell stuff like that all the time. After all, when I buy my third D2X or sixth SB-800, I don't need to OTFM because I already RTFM that came with the first one!

And Chuck: YOU GO GIRL! :-)
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Ron Scheffler, Photographer
Hamilton (Toronto area) | Ontario | Canada | Posted: 7:37 PM on 01.14.09
->> Cory,

Thanks for posting the list. I find it very interesting and informative because I've used the 16-35 for years in a way that assumes it's parfocal and when I upgraded to the 16-35 II I noticed much less consistent results. With the II lens I focus at each focal length for best focus. It might also explain inconsistent results with the 70-200 f/4L IS...

Is there a link to website/forum/blog where you found the list posted by Chuck Westfall, or did he send it to you directly? I only ask because if it's from another forum/blog, it would be interesting to read for additional background info.
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Stew Milne, Photographer
Providence | RI | USA | Posted: 8:29 PM on 01.14.09
->> Dave, your argument about not opening a manual makes sense if it is your second or sixth camera body or flash, but if it's your first and only lens, then I stand by my statement.

Anyway, this thread wasn't really about reading your manuals, but knowing your equipment, and I find it interesting that the 70-200 is listed as a parfocal, but I know mine sure doesn't act like one.
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Thread Title: Canon EF 70-200/2.8 focus issues -- HOW to FOCUS A ZOOM LENS
Thread Started By: Cory Lum
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