test shots for assessing exposure with 4x5 sheet film

[Pasto]

I'm spending quite a bit of time now using my 4x5 indoors. I've managed to stay away from flashes so far. More recently, I've been photographing more elaborate interiors and flash now seems like a real possibility maybe even a necessity. I'm thinking about using instant film to help me judge proper exposure when using falsh. My prefered indoor color film is Portra 400NC, but I may decide to use 160NC with flash. I only have small portable strobes (Metz 45 and 40, as well as 2 Nikon speedlights). Not a lot of power but that's all I have :) I would appreciate advice on materials/procedures/tips for doing this (i.e., using instant film to test exposure), as I've never done this before.

[jeffreyg]

A flash meter and some slaves would be helpful.
http://jeffreyglasser.com/

[Pasto]

So, no need for instant film?

[John Koehrer]

There's a pretty limited selection of instant films isn't there?
Flash meter's going to be less expensive than the film but having a print in hand is useful to see how the lighting actually looks so, use the meter to set the lights & instant film to evaluate the result.

[Konical]

Good Afternoon, Luigi,

Ditto on the flash meter suggestion. If circumstances permit, it can be helpful to shoot the scene first with B & W film of the same speed as your color film. Processing a batch of negatives takes less than an hour. If you don't normally process sheet film but your camera takes a roll film back, that may also be an option with B & W. Judging negatives is a bit tricky, but contact sheets don't take long to make if necessary. After a while, experience will begin to be very helpful.

Konical

[2F/2F]

I wouldn't rely on instant film, or a digital camera, to judge film exposure in anything but a rough manner. There is way too much difference in the way these media render a scene and the way a film emulsion renders it. The prints are better suited to giving one a warning of possible lighting and compositional problems that were missed by eye; to double check ones setup before exposing it onto film. I use them rarely, and almost always with flash, to check the qualities of the lighting I have rigged up. I might use them for what you are doing, and definitely would do so if I was getting paid enough to cover the [expensive] materials.

[pgomena]

Ditto 2F/2F. Judging exposure from instant film is tough. It takes practice (lots of expensive instant film). Instant film is contrastier by nature than regular film, and you have to figure in reciprocity effects for both emulsions.

Peter Gomena

[Mainecoonmaniac]

When I shot professionally, I used to use tons of Polaroid. Since the instant film is so hard to come by, I would use a digital camera to do testing. I also did multiple shots on sheet film and procesessed test sheets to see if I need to push or pull process other shots exposed identically. A shoot sheets to record exposures will also help.

[jnanian]

hi luigi

i am not sure if this is helpful or not, but if you haven't seen it,
look for a copy of Ross Lowell's Matter of Light & Depth (http://www.lowel.com/book.htm)

you might look for a set of hot lights ( tungsten ) or lowel L lights ( take standard 1/4 flood bulbs )
they are often times very inexpensive and very helpful when lighting a tricky interior, so you can
actually SEE the light, and how it is behaving in the space you are photographing ( shadows, brightness &C ).

you can sometimes find a case filled with 10+ L lights on that auction site for not very much money ...

good luck !

john

[Pasto]

Thanks to all for the helpful comments. These are very much appreciated.