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02-05-2011, 10:25 AM - 1 Like   #1
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FA*300mm F4 on 645d

Just a pair of shots and crops.I think this is another example on the lenghtening list of lenses with very good performance on the 645d.
The 300 required an AF correction of -3 to obtain perfect focus..
I have the camera from just a few days, and learning to use it, so not completely sure
of my results, but at the moment the only no no is the 645 FA45 2,8.
Full size jpg available on flickr.




100% crop (note the spider web wire from the leave 1 pixel wide)






100% crop center




100% crop near lower corner






Sergio

02-07-2011, 01:57 AM   #2
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Looks very clean and crisp to me, Sergio. I don't see any color fringing...
02-07-2011, 11:38 AM   #3
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Very comparable to what I see with the FA* 300mm on 645D here. The only issue I have is when mounted on a solid tripod but with only single point support such as the lens foot clamped to the ball head. There is detail loss (presumably from shutter shake) if the shutter speed drops below around 1/250s, rendering all such frames useless. At higher shutter speeds, or when shooting hand-held, it's a great combination.
02-07-2011, 01:07 PM   #4
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Royce,
I don't have problems at any shutter speed. But my tripod is an old one I used with large format view
cameras with 3 axis articulating movements. Unfortunately weight is exactly 20 lbs....



02-07-2011, 03:15 PM   #5
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I've tried that orientation as well, camera clamped to the ballhead instead of lens clamped to the head. But I still see loss of critical sharpness from shutter-induced vibration, at slower shutter speeds. Perhaps with a more massive support I could eliminate it but that's going the wrong direction for me in terms of weight. Especially considering that I've already scaled up the weight by going from a 5D Mk II rig to the 645D rig.
02-07-2011, 06:10 PM   #6
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I wonder how the less expensive 300mm FA 5.6 performs?

Steven
02-07-2011, 08:17 PM   #7
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Royce - I had/solved similar problems with a Mamiya 645AF 300/4.5 - nearly the same foot design (e.g. most rearward) - you may want to consider a single plate like RRS attached to the body and lens with a shim plate under the body to match the level of the foot. In that configuration you do give up body rotation - you'll have to use the ballhead instead of the collar.
02-07-2011, 10:46 PM   #8
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Thanks VoltMan, I'm indeed looking into something along those lines...

02-08-2011, 01:10 AM   #9
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superlative results, nice to see the FA* keeps it's stellar reputation.
02-08-2011, 04:14 PM   #10
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I would love to have this lens

Steven
02-08-2011, 05:22 PM   #11
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I once thought I bought it. Adorama sent me the A version instead. Yet returning it meant I had to pay shipment & insurance - from the UK not inconsiderable. And in the end, I liked the lens and the price was indeed commensurate with the A. This lens has the same optical design as the FA, but apart from manual focus it lacks the tripod mount.
02-08-2011, 05:37 PM   #12
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QuoteOriginally posted by Smolk Quote
it lacks the tripod mount.
That would make it somewhat more difficult to use on the 645D due to the way mirror/shutter vibrations propagate.
02-08-2011, 06:15 PM   #13
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QuoteOriginally posted by Digitalis Quote
That would make it somewhat more difficult to use on the 645D due to the way mirror/shutter vibrations propagate.
Yes, I'm looking for a mount, read somewhere that Canon may have suitable mounts I could use but have to check, perhaps with Calumet in London
02-08-2011, 06:27 PM   #14
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Actually I don't find that true in practice - medium tele lenses especially with a rotating collar/mount are just as (if not more) susceptible to vibration issues - probably due to the looser required tolerances in the collar which allows slight movement. On the other hand lenses supported by body mount only require a v. stiff plate and connection to the tripod. The best solution I've found for any tele (Nikon, Mamiya MF, Contax 645) is a 2 point support which puts the fulcrum in the center, e.g. using a "U" frame carrier for the lens (e.g. Mamiya RZ tele) but those aren't widely adopted. Also putting a sandbag on top of the lens to preload the bearings in the collar seems to help - did this many times with a Nikon 600mm with great results.

QuoteOriginally posted by Digitalis Quote
That would make it somewhat more difficult to use on the 645D due to the way mirror/shutter vibrations propagate.
02-08-2011, 11:44 PM   #15
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you are quite correct in regards to looser tolerances with tripod collars, my sigma 100-300mm f/4 IF APO EX DG suffered from these kinds of vibrations, therefore I applied some self-adhesive velvet to tighten up the grip the tripod collar had on the lens, and The modification has substantially improved stability.

I use the manfrotto 359 long lens support in along with a gimbal head for my 400mm and over lenses. This combination while being slightly slower to lock down provides excellent stability.

But nothing can help you if you aren't using a solid tripod head and legs to start with. My manfrotto 405 should be ideal for the 645D, with lenses up to 400mm and perhaps beyond.
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