shawn
Veteran
I was curious to see how my accurate my S2A shutter is so I hooked it up to a Phochron XA tester
I shot 4 tests at each speed and the tester gives an average speed as well as the min/max for each speed.
1 second = average of 1/1.05 (min 1.03, max 1.08)
1/2 second = average of 1/2.08 (min 1/2.02, max 1/2.13)
1/4 second = average 1/4.01 (min 1/3.93, max 1/4.26)
1/8 second = average of 1/11.1 (min 1/11.0, max 1/11.1)
1/15 second = average of 1/16.8 (min 1/16.6, max 1/16.9)
1/30 second = average of 1/28.5 (min 1/28.4, max 1/28.6)
1/60 second = average of 1/66.5 (min 1/66.3, max 1/66.8)
1/125 second = average of 1/133 (min 1/132, max 1/135)
1/250 second = average of 1/259 (min 1/256, max 1/261)
1/500 second = average of 1/448 (min 1/441, max 1/452)
1/1000 second = average of 1/719 (min 1/689, max 1/782) Min 1.278mx max 1.450ms
The 1/1000 is about half a stop slow but For a 50+ year old mechanical shutter I am very impressed with the accuracy and especially the consistency of these.


I shot 4 tests at each speed and the tester gives an average speed as well as the min/max for each speed.

1 second = average of 1/1.05 (min 1.03, max 1.08)
1/2 second = average of 1/2.08 (min 1/2.02, max 1/2.13)
1/4 second = average 1/4.01 (min 1/3.93, max 1/4.26)
1/8 second = average of 1/11.1 (min 1/11.0, max 1/11.1)
1/15 second = average of 1/16.8 (min 1/16.6, max 1/16.9)
1/30 second = average of 1/28.5 (min 1/28.4, max 1/28.6)
1/60 second = average of 1/66.5 (min 1/66.3, max 1/66.8)
1/125 second = average of 1/133 (min 1/132, max 1/135)
1/250 second = average of 1/259 (min 1/256, max 1/261)
1/500 second = average of 1/448 (min 1/441, max 1/452)
1/1000 second = average of 1/719 (min 1/689, max 1/782) Min 1.278mx max 1.450ms
The 1/1000 is about half a stop slow but For a 50+ year old mechanical shutter I am very impressed with the accuracy and especially the consistency of these.