I just got a 6-1/2 inch highly polished deep dish reflector for my Kalart flash unit. To date I've been using a 5-1/2 inch polished semi flat dish reflector on my camera. Typically exposures come out good using mostly 11 and 5 bulbs however I get a bit of corner vignette. Is it possible this larger deep dish reflector will eliminate this problem... or make it worse ?

I always make sure my bulbs are centered especially when changing from the Mazda to the miniature adapter.

Camera is a Baby Speed with a 120 roll film back (2-1/4 x 3-1/4) and a 101mm Optar lens. Pics without flash don't exhibit vignette.

I just don't get it... unless it has something to do with using the different size bulbs. On occasion I'll use a 2, 22 or a Wabash 3 in the flat dish and there is no vignette.

TIA,
George

The smaller reflector will throw a narrower light pattern. The 6 1/2 inch reflector will throw a wider pattern and may cure the problem.
Does your flash use the focusing reflector system? On these the reflctor can be moved back and forth to focus the light beam for subjects at different distances.
All the way back for distant scenes and all the way forward for close distances. It's possible I'm not thinking of the model you have, though.

Thanks Glenn. The Kalart reflectors are fixed. This weekend I'll take some similar snaps with both reflectors using 5's and 11's. I'm hoping the larger reflector will do the trick.

I have to assume, then, that you have the black plastic handle model? That flat reflector that comes with those casts a very wide beam but loses much of it as it gets farther from center. That could be the whole problem unless you're shooting at portrait distance or closer. Did I guess right this time?

The flash handle is metal however it uses the same reflector as the black one you mentioned. I think you're right about the beam cast as I mostly do on location full length people shots. It appears that the further the camera is from the subject the more the corner light falls off (vignette). The larger deep dish reflector hopefully will solve this problem. It doesn't have to be 100% but the vignette is just too extreme with the shallow dish reflector. I'll know soon enough after I take some snaps this weekend.

Ya know, in the olden days when I used stroboscopic speed lights on camera I never had this problem. Now using modern flashbulbs it's a whole new learning experience.

George-It's definitely the reflector-it's so shallow that light just goes all over. The deeper reflector will concentrate the light better. I used those Kalarts with the small, almost flat reflectors. Great with a longish lens, indoors with a ceiling to bounce light off of.
Not so hot with a normal/wide lens, outdoors, or further than 15-20 feet from subject. C-cell Kalart guns were made for 35 mm and Rollieflex TLRs. Even with a 2x3 Speed Graphic, I'd recommend a 2 D-cell unit with 7 inch reflector if you're using big old Edison-base # 11 and 22 bulbs.
The reason the strobe didn't do this is because its light source was built into a reflector which was already optimized for coverage. Big flashbulb in a small, shallow reflector is almost like flashpowder-it's a lot of light, but it goes everywhere.

DHF845... thanks so much, now I get it. I'll soup the roll I shot and see if the Kalart deep reflector did the job. If not I'll look around for a good old 7 inch reflector flash gun meant for bigger bulbs.

FWIW: The larger deeper reflector works great.