Measuring your shutter speed without any new equipment

[Peter K]

The larger shutters the worse the problem.

What problem?

Normaly a shutter is used to expose a light sensitive material like film to the light formed with an optical system. And if you will see, or measure, no difference in density also if the shutter has a tolerance of 30 % there is no need to hold the tolercances below this value. It's much more important a shutter works well in different enviroments like different temperatures, humidity, dust etc.

And for other applications like for very short exposure-times there are shutters without any moving part aviable like "Kerr's cell". Or with very small moving parts like the "light valve" used for the sound of movies.

Peter

[BetterSense]

I agree that in principle the DSLR test is more accurate, since it actually is integrating the light coming in the lens. I wouldn't have thought of such a clever way to achieve this!

Practically, my opinion is that the sound card test is well within accuracy expectations most of the time. At high (200+) speeds, large apertures (which does change the 'effective' shutter speed), or large lenses, simply measuring the 'open time' could be inaccurate for exposure purposes. Probably not drastically, though.

[Ivan J. Eberle]

I just think you're making it harder on yourself than you need to, that's all.

How are you comparing multiple exposures to gauge shutter timing consistency? Is it fast and easy? (It sure is slick and dead simple to measure the mean shutter open to mean shutter closing duration via the graphical interface in Audacity.)

I'll be the first to admit that integrated light readings could be useful. However, they'd more useful, I'd think, to determine your real f/stop ratings once you know you have a well-timed shutter.

Film was traditionally used for this purpose. Probably still most useful for determining the system integrity (i.e. light leaks).