Flash sync

[eggman6]

I dont understand the concept of studio photography and lighting so much, but i gather a sync as low as 1/30 is considered useless for portrait photography. What kind of limitations does a flash sync of 1/80 cause as aposed to one of 1/200 or so. I'm geussing it limits the range of situations you can use the flash mode in, but how and in what cases i dont know.

Any advice or links would be helpful.

 

[projectbluebird]

The higher the flash sync, the faster the shutter speed you can use. The faster the usable shutter speed, the longer the lens you can use. Portraits tend to be taken with longer lenses, so higher speeds are a good idea.

Personally, I try to use flash as little as possible. There are enough variables already!

 

[rxmd]

The focal length of the lens is actually irrelevant when using flash, because the flash lasts a few microseconds and you're unlikely to shake the camera much during that time.

But the faster the shutter speed, the better you can do fill-in flash outside without getting aperture issues. It does make a real difference. Imagine standing outside on a sunny day, you need flash to brighten your subject against the background, you have 100 ASA film loaded, your lens goes down to f/16, and your flash sync speed is 1/30. What do you do?

Philipp

 

[eggman6]

Thanks for the info. I had a rough idea but i wasn't sure. So anything under 100 can really limit your shots. Doesn't the leica m7 have a really low sync at about 1/50.

In studio photography is it possible to copensate with other lighting equipment for instances where a flash couldn't be used. I've recently taken interest in this and cameras i have my eye on have a low flash sync at about 1/80.

 

[rxmd]

Doesn't the leica m7 have a really low sync at about 1/50.

It does. Flash-wise the Leica sucks.

In studio photography is it possible to copensate with other lighting equipment for instances where a flash couldn't be used. I've recently taken interest in this and cameras i have my eye on have a low flash sync at about 1/80.

Firstly I'm not much of a studio shooter at present so I guess there's other RFFers with more hands-on experience. Of course you can always replace flash with conventional lighting. However flash units tend to be quite powerful, so you may need a lot of studio lights to replace flash units. Those tend to put out a lot of heat, too, which can be a problem when using light-shaping accessories like reflectors or colour filters, or with regards to your energy bill if you do a lot of studio work.

If you only work in the studio under artificial light, and if you only use flash, then you can happily shoot at 1/30 because all your light comes from the flash anyway. You shoot at 1/30, regulate brightness for the scene with the flash, and for the camera with the aperture control. It can be a hassle to get everything right, but it's possible. However sync speed is problematic when you have a bright scene where more of your light does not come from the flash. Basically any scene where without flash you'd have to use a faster speed than your sync speed becomes impossible to photograph. Beyond that it's a matter of control over the absolute lighting. So if you're using 100 ASA film and your scene is well-lit and already without flash you could shoot at 1/50 and f/11, you don't have a lot of control over the lighting at all, because all control you have is by stopping down a stop or two. So the best you get is a 1:1 or 1:2 ratio between flash and ambient lighting, and only by stopping down, so in order to get the lighting right you have to relinquish control over DOF. With a higher sync speed you can retain more control over the ratio of flash and ambient lighting, while maintaining the option of using open aperture. You can always start fiddling around with ND filters but that's stupid and a bit of a hassle and you get into trouble when you want to use other filters, too.

Whether 1/80 is enough or not depends. It's not bad, but not great either. I don't know what camera you're thinking of. If you're talking about medium format cameras, you're unlikely to get anything better unless you buy a lens with built-in shutter (which is the reason why these exist). If you're talking about 35mm cameras, and you expect to do a lot of flash work, you might think of getting another body for that. I went from a Canon AE-1P (1/60 sync speed) to a T90 (1/250) and it makes a lot of difference. It really depends on your scenario and your camera.

Philipp

 

[NickTrop]

Hence the beauty of the fixed lens rangefinder...

Leaf shutters - which all classic fixed lens rangefinders have, sync shutter at all speed.

Cloth focal plane shutters - all SLRs and interchangeable lens rangefinders sync up to a particular shutter speed.

It's an engineering thing, I won't get into the detals.

Classic fixed lens leaf shutter rangefinders are usually limited to 1/500 of a second top shutter speed. Cloth (or metal "venetian blind" variations) focal plane shutters give you a faster top shutter speed 1/1000, 1/2000 or more.

From a practical standpoint, the top shutter speed of 1/500th is plenty fast.

Indoor posed shots "still subjects" - slower shutter speed. 1/30th. Yep. Gets rid of those annoying, nasty, picture wrecking harsh shadows of of the flash because it "mixes" whatever natural light is in the scene with the flash.

Outdoors - obviously not "candid" or street shots, stop down a stop or two (print film affords you this latitude) from what the meter tells you for fill flash, which eliminates harsh shadows on faces caused by bright sunlight and isolates the subject from the background. In order to do this you will usually need complete control of the shutter and the ability to set the shutter speed at 1/250 or more typically 1/500.

The "cheap Chevy" classic leaf shutter fixed lens rangefinders let you do this...

The "Rolls Royce" focal plane shutter Leicas? Not so much.