Luminous Landscape Forum
Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: studio347 on June 02, 2012, 03:37:14 pm
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Hi,
Are there any unexpected disadvantages when using the fastest shutter speed?
For example, 1/500 S of copal shutter or 1/800 S of Hassel_HC 100 lens...
Common sense tells me that don't push too much since it's near the limit of the shutter's ability. But I'm guessing that the makers did some tests before installing the functions.
Any thoughts?
Thanks!
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I have absolutely no idea why it would be a bad idea. The shutter just opens and closes and I have never had an issue with one. If in doubt a couple of test shots should give you the info you need.
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Unless you see a marked difference in exposures , I don't see a problem.
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With a leaf shutter shooting at 1/500 about f/11 or so and smaller, you need to test to see if you need to correct the exposure since many times you will get a little bit more light on your sensor/film due to the shutter mechanics at that aperture. At wider apertures, it's not an issue. It's just the nature of the beast and something leftover from the days of film.
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Thanks for the rely.
When a car's maximum speed is 120 MPH, for example, it might be not a good idea to drive the car at 120 MPH all the time...
Maybe I'm wrong. It might be perfectly fine : )
Since I'm dealing with a leaf shutter( either copal shutter or HC shutter), I have another question for the shape of aperture in these shutters.
When I look through the inside lens, the aperture shape is not perfectly symmetric. It's a little irregular shape.
Does it affect the light fall-off of lens? I guess so... a little. Does it affect the image quality of lens? I'm not so sure about this...
Sorry that it's a little too technical question. When I see the irregular(not-perfectly symmetric) shape of aperture, I was wondering if this shutter has a mechanical problem.
But I also remember that some other shutters, which I have, show a little irregular shapes ...
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The aperture mechanism is made up of a series of overlapping leaves, which give you an iris diaphragm that is continuously adjustable. Perhaps it would be best for you to get a book on basic photography which will show diagrams of the principle parts of a camera and lens.
The number of blades in the diaphragm can affect the look of out of focus parts of an image - the more blades generally the better.
Jim
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The speed at which the shutter moves is the same no matter the setting. All you are doing is changing the delay. There is no wear difference. Cameras are not cars.
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The speed at which the shutter moves is the same no matter the setting. All you are doing is changing the delay. There is no wear difference. Cameras are not cars.
That is not entirely correct. According to Hasselblad, "Mechanical components gradually drift out of tolerance through regular use - affecting focus, shutter speed accuracy, frame spacing and other vital functions".
Although one can argue that the wear affects all shutter speeds equally, I believe it is more correct to expect the fastest mechanical speeds of 1/500 to be affected more. In other words, shooting a scene at 1/500 and f/2.8 may not produce the same exposure as (theoretically equivalent) 1/60 and f/8. But once you do the test and you confirm there is no practical difference, then I do not see any further "danger" of shooting at the fastest speed.
The accuracy issue is a bit different for the OP's other example, 1/800. It is a combination of electronic and mechanical mechanisms, or as Hassleblad calls it "’mechatronical", and is, again according to Hasselblad, far more precise than mechanical shutters. They claim they use more stringent standards than ISO, and that, in fact, their 1/800 could be safely labeled 1/1000 according to ISO.
Hasselblad also claims that the effect of smaller apertures on shutter speed accuracy is eliminated by their True Exposure mode (i.e, "if the aperture is small, the light opening is cleared a little earlier and closed a little later than when the aperture is wide open.")
Actually, Hasselblad has a pdf on the subject: Shutter at High Speed. (http://www.hasselblad.com/media/1664043/shutterathighspeed.pdf)
Hope this helps.
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This is all well and good insofar as the control of light reaching film or sensor for exposure is concerned; problems are different when you think of it in terms of flash synch. and/or also motion-stopping ability.
Rob C