Fill Flash

Mablo

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I know rangefinder cameras are considered hopeless flash rigs because of the 1/50s sync speed. But I just happen to like rangefinder cameras and I need a flash from time to time. Mostly fill flash.

Let's see if I get this sorted out. I'm shooting outside on a sunny day, let's say that the ambient light is f/11 on the sunny-16 scale. Quite a typical scene for fill flash use. I'm using a common auto-thyristor type of flash. So I dial in f/8 on my flash (instead of f/11) for one stop fill.

Shutter speed is naturally fixed to 1/50s.

If I'd be using Tri-X I'd run out of small enough apertures on the lens. I would need f/32. I guess this is why people think rangefinders are no good with fill flash.

But if I use a ASA 50 film everything falls nicely into place. I dial in f/11 on the lens and f/8 on the flash and shoot away.

Am I missing something here?
 
Flash power and recycling...f8 at 50 is a lot of light. If you're shooting portraits it's a lot to blast a person with directly into their eyes too...
 
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Had a thread about this running in "technique".

I've done some messing around with it, and honestly, you can run the flash a few stops under the prescribed exposure for fill. It all has to do with the latitude of the film and the exposure setting on the camera.

Example: Sunny day. Mid-late afternoon. Harsh shadows on the face when someone turns away from the sun.

Now if we do sunny 16, then proper exposure for the sunny side is f/16 (at prescibed shutter speed for film) and the shadowy side is f/5.6 --Three (3) stops difference.

Now, here's where it's important to know film latitude. Lets take Portra 160vc for example (I use this because I know the latitude) it tolerates 2 stops underexposure and 3 stops over.

So here's the deal--right now, your subject (in the shadow) in this hypothetical situation is 3 stops behind the background, when 2 stops is all it can handle according to the film lattitude.

Thus, if you brighten the subject up by just one stop, it's going to come out--even though it's technically 2 stops underexposed.

My point is, one stop under on the fill flash may be too bright. Too obvious. The point of fill flash is to be rather transparent--it fills in the dark areas that are beyond the scope of the films latitude.

Also, I understand your problem with 400 speed film and the 1/50 flash limit. Unfortunately, that's the way it is. If you want to shoot higher speeds, you may have to get a flash that offers more exsposure variation. I know a Vivitar 285hv could cover that.

Hope that helps--not really sure if it will or not.
 
With f/11 I use between f/8 and f/5.6 or just f/5.6 with some of my flashes, on others it is 2 or more stops. You will have to test. I'm not sure how good the sensors are is full sun, but I have to say they always seem to work. Also, if you are crazy enough you could use a ND filter to adjust either the shutter speed or the aperture. But that is a little out there.

I have had f/22 (at 1/50) at times with a weak flash that would only give me f/4 on auto and the fill was fine, maybe even better.

I have used fill flash off camera and coming in at 45 degrees, but this was for special situations. Generally, on axis fill flash is what is recommended. So using your hotshoe is great.
 
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Thanks for your ideas. Maybe one stop fill is too bright, I can buy that, but all in all using 50 ASA film will in essence let me circumvent the often cited Leica 'slow sync speed problem' and using flash is actually a breeze. At least in theory.

I'm going to test my hypothesis and ordered today a brick of Ilford Pan F 50 for the purpose.
 
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