light meters

[Clive Gray]

You can also use the film plane metering probes from the Sinar system with non metering backs or other makes of camera if you have the metering cassettes it is less ideal but perfectly useable.

[Ivan J. Eberle]

Learning how to program a meter or compensate it is probably about as difficult as doing the maths in your head. The benefit of not offsetting the meter is the next reading will not be skewed if you forget to zero out the meter.
If shooting modern neg films, it's all pretty easy. If transparency, it's more critical.

[Doremus Scudder]

I think many make the issue of compensating for bellows draw much too complicated.

My solution: A table with bellows compensations for all my lenses and a small tape measure.

By the time you've put your disc in the scene and taken it out again (and then measured it on the ground glass and consulted a table...), or fiddled with your iPhone or hand-held computer, or twisted the ISO dial on your meter (which you may forget to reset...), or done the mental gymnastics to come up with a rough estimate (and maybe not got it right... do it again to check...), I've measured my bellows draw and looked up the exact compensation in either shutter speed or aperture change on my little table.

If you're dealing with close-up work, the time it takes to measure bellows draw and consult a table is a miniscule fraction of the time it takes set up the shot and is often fewer steps than other methods of finding the bellows compensation. Plus, it is accurate and you don't have to do calculations when you should be concentrating on composition and getting the shot right.

Best,

Doremus

[Henry Larson]

Are there any light meters that take into account bellows extension?

My LunaPRO sbc has a bellows extension function.
It is described in detail in the Lunapro sbc instruction manual

[Jim Jones]

Some small format macro accessories such as bellows and extension tubes came with a scale to be placed in the plane of focus which would directly read information such as magnifiation and exposure factor. This one came with Spiratone extension tubes. The inch and metric scale is not part of the macro scale, but added for reference. A similar aide for any large format could easily be calculated by anyone proficient with modern calculators. I'm too rusty with a slide rule to volunteer.

[Leigh]

A similar aide for any large format could easily be calculated by anyone proficient with modern calculators.

Calumet sells such a set for $10.95 IIRC. I bought a couple of them last year.

It consists of two pieces:
1) a high-contrast square target that's placed in the scene at the desired plane of focus; and
2) a little scale to read the bellows factor directly from the image of the target on the ground glass.

Very nice item.

- Leigh