Advice re: 1.4x III extender

[samthefish]

Lemme give you an idea of my equipment:

7D, 24-105 f4L, 17-55 2.8 (EF-s), 100mm IS Macro, 70-200 IS II, Sigma 10-22, 1.4x extender

For every lens up until the 1.4x extender I've been happy with the sharpness so I've never messed with AF microadjustment.  I recently bought the 1.4x extender to add some reach to the 70-200 for sports and photos of critters in the yard.    The other day I took about 20 photographs of a chipmunk, used just the center focus point, braced myself against house and used IS mode 1, f4.0 @ 1/250.  Not one of the photos came out sharp.  I then tried mounting camera on a tripod, doing mirror lockup remote release and taking some photos of a remote squirrel with just the 70-200 (@200) and with the 1.4x extender added.  I really couldn't see any advantage of having the extender as I could get a sharper image from just enlarging the native 70-200 lens photo.

I then tried a poor man's calibration by putting a ruler at an angle and trying some different AF microadjustment settings ... the best I can figure it's best setting is about +12.  Even then it's not as sharp as native but I expected to loose some sharpness with the extender.

I realize the "every lens is different" but doesn't that seem like a lot of adjustment?  Am I better off trying to exchange it?

Also what's everyone else's experience with the extenders?  When it comes down to it I still wonder if I'm not getting an as good or better photo by just cropping the photos from the 70-200mm lens.  Also not loosing the one stop of light.

Any ideas or experiences welcome...

SamTheFish

[neuroanatomist]

I then tried a poor man's calibration by putting a ruler at an angle and trying some different AF microadjustment settings ... the best I can figure it's best setting is about +12.  Even then it's not as sharp as native but I expected to loose some sharpness with the extender.

I realize the "every lens is different" but doesn't that seem like a lot of adjustment?  Am I better off trying to exchange it?

Not the best way to do that (see this thread for a longer discussion of AFMA), but a +12 adjustment is not unreasonable.  With my 5DII, the 70-200mm f/2.8L IS II is at -3, and when I add my 1.4x II it's +4.

Also what's everyone else's experience with the extenders?  When it comes down to it I still wonder if I'm not getting an as good or better photo by just cropping the photos from the 70-200mm lens.  Also not loosing the one stop of light.

Extenders are at their best when used with the supertele primes (300/2.8, 400/2.8, 500/4, etc.).  They are not as good with zooms, although the 70-200mm II is arguably the best zoom lens available, any lens takes a hit on sharpness when used with an extender.

IMO, an extender is for occasional use only.  If you need a certain focal length, get it.  My 100-400mm, older design though it is, is optically better than my 70-200mm II with either the 1.4x or 2x extenders.  I use an extender only in two situations - 1) I am traveling with the 5DII, and don't want to bring the 100-400mm and the 70-200mm II, and 2) I am using my 7D in the rain, and the 70-200mm II + TC is weather-sealed, whereas the 100-400mm is not. 

Sharpness is still decent - here's a rainy-day shot with 2x extender (which delivers a bigger IQ hit than the 1.4x):


EOS 7D, EF 70-200mm f/2.8L II IS USM + EF 2x II Extender @ 400mm, 1/160 s, f/5.6, ISO 3200

[samthefish]

Thanks for the info - nice photo of the bird, BTW, looks sharper than what I was getting.    I would love to get a 300mm prime lens but for budget / space reasons was hoping the 1.4x extender would give me something "good enough" with my 70-200 and some flexibility.  I like the idea that for soccer I could put it on and then to shoot a basketball game take it off.  I also liked that it's water sealed. 

I'll see if I can't calibrate it a little more accurately and use it for a bit more before figuring out what to do.  I'm definitively not a "pixel peeper" but in this case it's the first thing I've gotten from Canon I wasn't happy with out of the box.

SamTheFish

[Aaron78]

I have a 7D with a 70-200 2.8 IS II with a 1.4 III extender, and the photos are pleasingly sharp considering the extra glass the extender adds.

[Mt Spokane Photography]

If you have a canon 1.4X MK III extender with a 70-200mm f/2.8 MK II, images should be very sharp.  The AF will be slower, and sharpness will be a bit less, but not a big hit.

Bad extenders do exist.  If focus is sharp without, return or exchange the extender.

[samthefish]

I called canon about it and they said no problem, send it in and we'll have it back to you in about a week.  I'll let you know if them calibrating it really helps.

BTW I've discovered that in my case you're much better off calling Canon than using email.  My first email to canon they said "send some sample photos" and a few days later no response.  Guy on the phone took 5 minutes to determine they should look at it and sent me an email describing how to ship it to them in NJ.  The customer care person was from NJ as well and understood the cameras/lenses very well.  All good things.

SamTheFish