I just acquired two lenses. One a Rodenstock Sironar N 210 in Copal 1 shutter and two... Rodenstock Sironar N 135 in Copal 0 shutter. While, I've always been vaguely aware that shutters do not often shoot the listed speed, I've never had a shutter checked for speed. I've presumed that film latitude, meter variances and other factors took care of some slack, although I know how such variances stacked up in one direction might have a negative effect on exposure (HAH!!)
However, I wonder how much of a factor this is, and how common it is to have a table of corrected shutter speeds for each shutter in your possession. Having seen camera's come back from service with a list of actual shutter speeds, it makes me wonder how likely it is that a service on a shutter can achieve listed speeds, or simply come back with a correction table.
The lens board on each of these lens has a table with actual speeds. They are:
Copal 1
1=1
2=2
4=4
8=8
15=15
30=30
60=52
125=108
250=216
400=300
Copal 0
1=1
2=3/4
4=3
8=8
15=20
30=20
60=60
125=125
250=250
500=450
Interesting to me that the big shutter is so correct on the slow speeds and quite off on the 1/400th, while the Copal 0 is the opposite.
How many of you concern yourselves with this aspect of your equipment. It seems that one could spend some time chasing the "perfect" shutter with all speeds matching the listed scale, as opposed to having a corrected table of speeds for each shutter. How big a factor is this?
And of course, then there is the aperture???? Should an aperture be re-scaled every time a new set of lens cells is screwed in?
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