Micro 4/3 Adapted lens - Canon FDn 200mm f2.8 on G1

BillN

Hall of Famer
Location
S W France
Name
Bill
Does anyone use this "adapted" lens

I have never been able to get anything in focus - shots appear to be in focus in the EVR but turn out badly - OOF and soft

Looking thru the G1 EVR - at Infinity, (on the lens barrel), is a blur and just before infinity seems to be infinity, (i.e. in focus on the EVR)

here are 4 shots that I took today trying to find focus points - taken at f8 (or maybe one at f2.8) - with high very shutter speeds, (so no shake) - and ISO100 or ISO200

to me they all look terrible, (maybe the building is semi OK - on second thoughts, no it's not OK)


canon_200_1.jpg


canon_200_2.jpg


canon_200_3.jpg


canon_200_4.jpg
 
Bill, it's the age old trouble of an adapter that doesn't hold the lens in quite the right place. Is there any way of adjusting it to move the lens mount on the adapter slightly further away from the camera sensor, it will probably only be three or four thousanths of an inch, excuse the imperial measure. I don't know with bayonet adapters, but I have some for Leica screw lenses where I have shimmed the threaded collar, which is separate from the bayonet part that mounts onto the camera, with three or four thicknesses of silver cooking foil. If that is possible it needs a little experimentation to get it right.

Barrie
 
I own several FD and nFD lenses which I have used very sporadically with m4/3 via adapter. I have found that with some (for example, 100mm 2.8 FD) there is some play in the mount. This could cause the lens to switch position after you have focused it, with the resulting loss of sharpness. I think Barrie's advice is right on the money and may be the solution.

Cheers,

Antonio
 
Go carefully Bill, if you think that the adapter performs ok with another lens, then Antonio's experience with play in the mount on the actual lens might be the problem. Worth looking closely at the mount on your 200mm lens and how it attaches to the lens body. Another way if it's possible is to remove the actual mount flange from the lens and re-attach that with thin shims behind it, which the camera manufacturer might well have done when the lens was built to fine tune it's focus point. That would achieve the same effect, but would throw the lens out when mounted on a Canon camera, in other words it would be adjusted solely to suit your G1 and that adapter.

Barrie
 
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