How often, if ever, do you use a light meter to set up shots in a studio setting? I have started to work in a small studio and they never use a light meter so many shots are over or under exposed. (kind of like guess and check) I was just wondering if this was normal or are light meters the norm?
Light meters are standard equipment in a professional studio - or they were when you shot 5x4/10x8. Saved a great deal of time and money. If you are using flash they are essential. You do find that with familiarity you get to know the flash exposure for a standard set-up - but you still use a light meter.
When using flash/strobes in a studio type setting, I use a light meter to set or check my ratio (key vs fill light) and to find my shooting aperture. However, once I'm in the ball park, I'll fine tune the exposure settings...based on what I see on the histogram.
In order to assure you are getting an accurate reading from your meter you must calibrate it to your digital camera. First take a gray card and attach it to a light stand or something else that can be moved in or out. Put your camera on a tripod and don't move it, camera settings should be any iso speed 125 and at f8. Take one studio light and put it directly over the camera and move the gray card in or out till you get a reading on your meter at f8.0. Once you have done that take a close up photo of just the gray card. Now take your cf card and put it in your computer and look at the histogram, it should have the peek directly in the center. If it does then your are calibrated correctly if not and it is to the left it means you are under exposed, now take your graycard light and move it closer to your camera and reshoot. Again take your cf card and put into your computer and look at the histogram again, if it still is not in the center and to the left you are still underexposed and again move the graycard closer again to the camea. Keep working with it till your spike is right in the middle. Now if your spike is on the right they you are over exposed, you will have to move your gray card further away from your camera and again reshoot and check it's histogram, keep doing it till the spike is in the center. Once your histogram is in the center now take your meter and again check it's reading at the gray card. It will show how far your meter is off. Most meters have a calibration adjustment that you can make, check your owners manual for it's location. Keep adjusting the calibration adjustment till your meter reads f8.0 at your gray card. It sounds complicated however it is really very simple. You should see a difference immediately in your exposure using you strobe immediately.
This is working on the principle that the meter in your camera is accurate - which is not always the case. If you invest in a professional meter they are already calibrated and are accurate (mine is accurate to less than 1/10th of a stop). The above proceedure will then show if your camera meter is accurate. But do remember that the proceedure only works with digital cameras. For film cameras the process is somewhat different.
If you are using a digital camera you need to make sure that your camera is recording the same exposure that your meter says it should. That is why you must calibrate the meter to the camera. With the exceptions of the cheaper meters the rest have a calibration adjustment for this purpose. Last year H&H Color Lab had a course where each person was to meter a person with their meter, set their cameras to exactly what the meter said to set it. From there they had an 8x10 printed without any correction. From there each person was to calibrate their meter to their cameras and reset the compensation for the camera not the meter. Again everyone took another photo, it again was printed with no correction done to the image. Towards the end of the class each person was first given the 8x10 that was taken using the reading of the meter prior to correction, then was given the other 8x10 of the image that was taken after their meter was calibrated to their camera. 100% of the class was in agreement that the second image was right on for exposure. If you doubt the results contact either Bentley or Jeff at H&H Color Lab and they too will confirm the results. Cameras sensor can and do vary even from the same manufacturer. I have been in this business for 30 years and purchase ONLY professional equipment. When I bought me newest meter they had 3 of the same ones. We set all three next to each other exactly the same distance from the light sourse and not one of them read exactly like the other, one might show 8.0, the other 5.6.8 another 8.3.
