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Anirban
Tinkerer Username: Anirban
Post Number: 10 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 13, 2007 - 01:01 am: |
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Hi Everyone! Does the shutter speed tester described by Rick Oleson here http://rick_oleson.tripod.com/index-135.html work for a speed of 1/2000s? My recently acquired Fujica ST-801 seems to show almost the same TV screen area at speeds of 1/1000s and 1/2000s. Thanks, Anirban |
Rick_oleson
Tinkerer Username: Rick_oleson
Post Number: 224 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 13, 2007 - 05:01 am: |
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Yes, it does; however, the difference may be hard to see for two reasons: first, the difference in band width between 1/1000 and 1/2000 second is very small, and second, there is a small dwell time in the phosphors in the CRT display which adds to the width of the band at any speed. This is a negligible amount at the slower speeds, but as you get beyond 1/1000 the difference may begin to become measurable. The effect of this would be that, although the band at 1/2000 is narrower than that at 1/1000, it may be a bit more than half as wide. I will try checking this with a digital camera and post the results up to 1/4000 second. |
Anirban
Tinkerer Username: Anirban
Post Number: 11 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 13, 2007 - 09:45 am: |
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Thanks Rick, for the information. If I understand it correctly, at any given point of time, some phosphors will be in a transition process of being "switched" on (because of scanning) , and some being switched off, resulting in a wider band, with the edges not bright enough. So, the sensitivity of the eye and the phosphor characteristics also come into play. Please keep us posted with your results. Anirban |
Rick_oleson
Tinkerer Username: Rick_oleson
Post Number: 227 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 13, 2007 - 10:45 pm: |
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Okay, I ran through the test with my Canon XTi (400D) at speeds from 1/60 through 1/4000 second. With my monitor, the test clearly shows the difference at each speed, the phosphor dwell is insignificant. Other CRTs may be different; it is just as likely, though, that the 1/2000 second speed in your Fujica is slow. Tolerances generally permit more error in the slow direction at the top end of the speed range, and a camera that old at 1/2000 may well have been less accurate than a modern one. Here are the results that I got with my Canon: http://rick_oleson.tripod.com/index-208.html |
Anirban
Tinkerer Username: Anirban
Post Number: 12 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Saturday, April 14, 2007 - 06:15 am: |
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Great information, Rick. Thanks a lot. |
Charlie
Tinkerer Username: Charlie
Post Number: 59 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Saturday, April 14, 2007 - 07:34 am: |
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Should a horizontally traveling shutter camera be held vertically? |
Anirban
Tinkerer Username: Anirban
Post Number: 13 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Saturday, April 14, 2007 - 10:30 am: |
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No, cameras with horizontal travelling shutters should be held horizontally (shutter slit travels laterally seen from the opened back for speeds more than the fastest flash sync speed). Vertically travelling shutters like the ones in most modern film cameras, should be held vertically, so that the slit travels laterally. |
Rick_oleson
Tinkerer Username: Rick_oleson
Post Number: 228 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Saturday, April 14, 2007 - 11:02 am: |
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That's correct: to make the photos in the above illustration, I had to hold the Canon vertically because it has a vertical-running shutter. |