no not where to get them (sitting on a gross) but here is the question I have with respect to my Crown Graphic 4x5 and using flashbulbs. As anticipated with the leaf shutter and the flash you can get a vingetting of the subject and darker out to the edges.

It's (IMHO) actually kinda cool and reminiscent of nostalgic photos. What I am doing is shooting photos at a friends Oscars theme party as guests arrive on the red carpet. Ya campy, I know, but they think it's fun. Going to be using a polaroid back and FujiFilm 100 color instamatic film so the guests will get to take their snaps home with them.

Ok. long way round the barn to get to the question. How can I control the degree of this light vignetting or at least calculate/guestimate to what degree I will have it in combination with say using the guide number on the flashbulb for distance / aperture? The flash is a Graflite with a 5 inch reflector, I am using either 25B or 5B bulbs (yes adjusting for different GN), also will either be shooting a 135mm Optar or 203 mm ektar.

THanks in advance!

more like that you will see any vingetting with the 203mm
just have give it a try

http://graflex.org/flash/navy/
http://www.donsbulbs.com/cgi-bin/r/t.pl
use the Library to find the photo bulb catalog for the brand of bulbs that you have.
http://graflex.org/helpboard/viewtopic.php?t=1453
http://www.southbristolviews.com/pics/Graphic/manual-pdf/GrafliteManual.pdf


Not being a flashbulb user I do not know off hand what will give you your required result but a misaligned reflector, mis adjusted solenoid/incorrect delay setting on the shutter, or weak batteries are some things that come to mind that may cause the desired effect.

If I understand what you are trying to achieve I would consider using a filter similar to a Cokin ~062, ~063, ~072, ~073 or Ambico 7731, 7981 or 7982 instead of trying to duplicate the light pattern of the flash bulb & reflector that we tried hard to avoid back when everybody used flash bulbs.
BTW the Cokin numbers would have either "A" or "P" where I indicate "~" for which Cokin System size you use.

C. Henry