This is the start of a write up I’m doing for the tips/techniques section; I decided to make a smaller post separate to catch everyone's attention.
For the camera setup I used a mamiya RB76 with a 90mm lens, Polaroid iso-3000 film as a base. For the exposure calculations I used a pentax V analog 1 degree spot meter. For the subject I used my mares mr-22 non-titanium, non-ruby 2nd stage. It is sitting on top of my pentax meter case and a gray card. My meter point is the shadow of the regulator. At this location “proper exposure” according to the meter gave me F/5.6 at 1/15 seconds.
For reference this is a gray card, a.k.a. Zone V. This is ‘middle gray.
This is an image with correct exposure. Note that the shadow of the meter is the same as the gray card (well not 100% but very close)
For the next shot I decided to over expose. I decided to use 1 second, which is 4 stops over exposed. Yes that’s a drastic over exposure but it suits the purpose. Note the detail on the meter case (the bag under the regulator). Also note the highlights on the bag are burned out.
For the final shot I decided to under expose. I used 1/400 seconds, 5 stops under exposed. Again this is drastic. Note only the very bright areas are visible.
Remember that the meter in the camera views the world as a gray card. If you wish to lighten or darken a scene then you need to adjust the exposure accordingly. This not only depends on the film you are using but the camera as well.