Do Canon FD lenses like the 24mm f2.8 or 50mm f1.8 have fixed aperitures? I was checking out those Canon FD to m4/3 adapters and they all seem to have open/close aperiture rings on them. Any reasin why? I thouht you could adjust the aperiture on the FD lenses by turning the aperiture ring on the lens?
Canon FD lenses fixed aperture?
- Thread starter Movie
- Start date
The open/close aperture rings on the knock-off FD to m43 adapters is a redundant nuisance. All FD lens were built with perfectly functional aperture rings. The FD to m43 adapter's open/close ring is mindlessly inherited from m43 adapters designed for Canon auto-focus lens which lack mechanical aperture rings.
stoneinapond
Veteran
Some old M42 lenses for Zenith SLR I owned had a similar open-close switch, so that you could select aperture by rotating the lens ring, flip the switch to open position to allow maximum light for focusing, then close (to selected aperture) for shooting. Yeah, so I agree this vestige from the past makes little sense on a live-view sensor, which I think is more light sensitive than human eye.
I am surprised you would say that. I think that continuous aperture ring adjustment is one of the most important features for video. Panasonic charges a ridiculous premium for their “HD” lenses. The only benefit to video quality for those lenses is that they have a continuously variable aperture. Otherwise they are poorly suited for indoor video because of their small relative apertures.
If you are only shooting pictures then I could definitely see why you wouldn't need a continuously variable aperture ring. However, this is a video forum so I would expect a lot of people use that ring.
With Manual focus lenses the only way to continuously vary the aperture is through the adapter aperture ring. Without that ring you are pretty much stuck with one aperture while filming.
Here are a few of the adapters I use with my FD and other manual focus lenses.
http://shop.ebay.com/rainbowimaging...adapter&_osacat=0&_trksid=p3911.c0.m270.l1313
MF lenses I use.
http://www.youtube.com/watch?v=7FPbqhFt_oY
Different shooting styles, but you're right, I shouldn't assume everyone uses a fixed aperture for each clip. It's a nice effect when you can keep the exposure constant while varying the aperture to change the depth of field. However, I've found the GH1's continuous auto-exposure compensation to be too twitchy to rely on and the crude aperture-lock rings on the m43 adapters hard to adjust without disturbing the shot.
I agree with you on Panasonic's "HD" lens - and there's only one so far, the 14-140mm kit lens. Continuously variable aperture is a frustrating feature on a lens that can't maintain anything below f5.6 across most of its zoom range.
Martti Ekstrand
Veteran
Well you can always let a camera workshop de-click the aperture ring. Or DIY if you are comfortable with fine mechanics.