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Why can't all lens diaphrams be like this one?
- Thread starter RichA
- Start date
V
Vivek
Guest
They need not be slow. Clear aperture of Rich's Wollensak (I have a 240/4.5) is likely to be ~60-70mm.
Of course they will be expensive! Even 5 bladed ones are!
Of course they will be expensive! Even 5 bladed ones are!
Godfrey
Well-known member
That's not what I mean. I mean that for an SLR, or any other auto-diaphragm camera, a many-bladed iris like this has a lot of static friction and is going to operate slowly as a result.
You'll never see a Nikon D3s running 8 fps with a lens that has an iris like this...
V
Vivek
Guest
Good point!
But, we do not have that problem with the m4/3rds and the CDAF, do we?:ROTFL:
BTW, Rich, I checked a few Kodak Anastigmats I have (and the Raptars) all have round apertures. The Schneider Clarons have them, APO Nikkors (process lenses) have them...
Godfrey
Well-known member
Well, all lenses built to date for Micro-FourThirds are designed for open-aperture metering and focusing with auto-iris operation. The cameras don't need it to operate well, but it does help.
RichA
New member
I've even seen some c-mount lenses with inward facing scallops on the aperture blades! Interesting what you come across.
D
duckrider
Guest
Aaaaahm, a D3s not, but my F2H will do 10per second with that lens:sleep006::
reason is: On the F2High speed the Nikkor lenses are always in stop down mode. If You press the "stop dowm" knob diaphragms open.
Camera was not able to close & open diaphragms 10 times a second....
be fast
Thomas