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Doug Dolde
13-May-2007, 12:49
Has anyone used fill flash for 4x5 outdoor landscapes? I know it's a common technique with 35mm (Galen Rowell style) but haven't seen much info on this for large format. I am thinking a lot more power would be needed than a small 35mm style strobe could provide. I shoot Provia 100F for the most part, once in a while Velvia 100F.


Any help greatly appreciated.

David A. Goldfarb
13-May-2007, 13:03
I have a Norman 200C setup that I usually use with 4x5", though I don't often use it with landscapes. Norman, Quantum, and Lumedyne all make portable barebulb systems that put out enough light for LF in the field.

Greg Lockrey
13-May-2007, 13:34
Why wouldn't a "35mm strobe" be large enough for a 4x5"? My old Metz 45CL-4 puts out a pretty bright and wide light. If it's just for fill after all.

Henry Ambrose
13-May-2007, 14:20
For fill in a sunlit scene you'll need lots of power and the further away the area to be filled is, the more power you'll need by far. My 1600ws monolights at fullpower and a standard reflector will fill against full sun at 10 feet. Add a softbox or umbrella and it drops off. You'll likely need a flash meter when adding light modifiers.

In terms of distance from light to sublect, exposure drops off by the inverse square - twice as far = one fourth the light. Even the most powerful on-camera flashes will poop out unless you can get them close to the subject to be filled.

Guide numbers will work, no meter required.

Guide Number = f/stop x Flash-to-subject distance

Assuming you know the GN for your flash (at its various settings) and the f stop in use you can calculate the distance from light to subject to get the flash exposure you want. And obviously knowing any two of the three parts of the equation lets you figure the third unknown.

For real control to see what you're lighting and how much you'll want Polaroid. But I'd hate to think about carrying all that stuff that around in a backpack.

C. D. Keth
13-May-2007, 15:29
Why not just take some bounce? It doesn't need power and if the sun is bright enough to need fill, it's bright enough to bounce for fill.

Nick_3536
13-May-2007, 15:34
Why wouldn't a "35mm strobe" be large enough for a 4x5"? My old Metz 45CL-4 puts out a pretty bright and wide light. If it's just for fill after all.

Personally I never considered the Metz 45 a 35mm flash. Maybe I need tougher standards :D

Greg Lockrey
13-May-2007, 17:35
Personally I never considered the Metz 45 a 35mm flash. Maybe I need tougher standards :D

I never heard of a "35mm flash", that's all. :) I've been more concerned with angle of coverage and power. Never considered the paramaters were different for different formats.

Frank Petronio
13-May-2007, 18:11
I just take off my hat and let the sun bounce off my dome reflector, aka beauty dish.

You see a lot of f/16 strobe against sun portraits in ESPN, Sports Illustrated, etc. and those guys are usually using a 2400 w/s Speedo/Profoto big boy strobe in a softbox to pull f/11-f/16 on ISO 100 film.

Doug Dolde
13-May-2007, 18:12
Frank, before I even saw your name on it I knew it was you.

Ben Calwell
15-May-2007, 05:16
I once shot a mission in California and used a small, shoe mount strobe to fill in the dark stone fountain in the foreground.
I didn't do any calculations, figuring that the little light, at full power, would pump just enough light in to fill the shadowed side of the fountain, and it did.

Gene McCluney
15-May-2007, 08:56
Using flash, any flash is not format specific at all. The only issue is that we normally use smaller f-stops with LF cameras. So, while a common F-stop for 35mm format cameras might be f8, this is not even getting started on many LF lenses. The same issues would apply shooting at f22, for example, no matter what format the camera is, and there are lots of us that like to shoot at even smaller apertures than f22 in LF. Those old press camera flash guns that used the large flash bulbs pumped out tons of light making flash photography quite feasable at smaller apertures.