While I admit a bias to photofloods, I have also shot thousands of shots with studio strobes. As a general rule in studio, using a good flashmeter, read at subject position with the incident dome in place and the meter pointing at the camera position. This integrates all the lights and seeks the proper exposure.
However, realize that just like camera technique everyone has their own metering technique. If you are getting consistent under exposure, you will need to re-rate your film or your sensor to a lower sensitivity. This is found through testing. With film it means taking a careful reading at the published ISO and making an identifiable exposure. Let us assume ISO100. Good meters let one set one exposure index in much finer incriments than most cameras, so try a shot at around ISO80 and ISO64. In other words downrate the sensitivity by a 1/3 stop bracket. Once the film is back, identify the ideal exposure and go with that.
ISO ratings for film are done in lab conditions using sensitometric measurements that don't necessarily translate into accurate settings for one's metering technique in the field. Pros buy large batches of film with a single emulsion number, and test it to get their individual exposure index. This raging is the one they use until that batch of film is used up. Regard the published ISO rating as a guide to where you may start to test for your own individualized rating.
With digital cameras, there is no problem using studio strobes. If you have a flashmeter it will save a bit of time, but the best exposure method is using trial and error. Do a test shot, review and adjust accordingly.
With studio strobes, the camera's metering is irrelevant, since all studio strobe work is done on manual exposure.
If you are using a dSLR, set it to the X-sync speed as listed in the manual. From there, all exposure is set by aperture ONLY. If the picture is dark, open the aperture and keep doing so bit by bit until the exposure is perfect. If the picture is light, stop down. Moving the lights closer will lighten the exposure and moving them back will darken it as well.
The same is true if using a prosumer camera like the CP5000 or CP5700, except that it will sync at ANY shutter speed. Use a high enough shutter speed to eliminate all the light from the modeling lights and then use the aperture to regulate exposure as above.
When shooting digital, the histogram is your best friend. Become familiar with it and it will keep you out of trouble. No matter what conditions I am shooting under, I am CONSTANTLY testing and checking the histogram. My exposures are rarely short of perfect - not because of talent, but because I fully utilize the histogram reading.
Shooting in a portrait studio, one gets to the point that you know about what f-stop to use by experience. One keeps the lights at reasonably constant distances, and the exposure varies only a little.
In kidnapping studios in chain stores, the lights may actually be fixed in place as well as the subject position. The formula never varies, and the results are completely consistent. Prints can be made very cheaply since every shot has exactly the same exposure and there is no need for individual attention.
Even in a studio where a photographer seeks the ideal lighting for each subject, the exposure will be remarkably consistent. If the nominal exposure is f-8.0, it will generally only vary perhaps by half a stop each way. Shooting day after day in one's studio, meters get lost and no one notices.
This does not apply to a commercial studio where product is shot. Prior to digital, product photographers checked their exposure with Polaroid when shooting strobe. Since then, product has gone almost totally digital and often with cameras directly tethered to computers and the strobes have been replaced.
The highest resolution backs work like a scanner, scanning the image at the focal plane of the camera - a medium or large format camera fitted with these backs. All shots are done with either incandescent lights or no-flicker fluorescents with very high CRIs (Colour Rendering Index). The backs have little or no memory of their own other than a little bit of buffer. Since the image is acquired directly into the computer, the moment the exposure is done it can be checked in software and the exposure adjusted.
larry! ICQ 76620504
