I have a 600mm mirror, and that's bad enough.
By trial and error, I have found that using the front grip at a 45 degree angle on the tripod ring reduces camera shake quite a lot. It gives a more natural posture and the movement when pressing the shutter trigger is minimised.
I might try the grip on the Sigma as well to see how it goes.
No point today, we are surrounded by Cornish mizzle.
I have found out today that this lens is the Noflexar B model, introduced in 1965.
The 1955 models had screw mounts between the various parts. the B model has breech bayonets. There are C and D models as well as some telephoto lenses.
Waiting for an OM>NEX adapter, so I can use the (very slightly) lighter one without the bellows unit.
Even with both hands, it is quite tiring to hold.
May get a monopod.
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