We are imaging many many 1000's of botanical specimens in botanical institutions in different countries. These are pressed plants mounted on flat usually white, rectangular, thin card - somewhat larger than A4. I have a tripod and 3 way head. A Nikon D750 with a Nikor 50 mm lens. I have good LED lighting. The camera is mounted on tripod facing down and had a release cable.
The plant specimens range from very flat to a little bulky max depth of a woody specimen may be 1.5 cm.
So our objective is to have sharp as possibleimages to put online. As a non-photographer, I want to get the best out of this excellent camera and with no movement and plenty of light, I guess it's possible to get top top results.
Im looking at what settings to choose for best results. Sharp and light images.
As an example, my ISO is set to 100; F16; Shutter speed I have at 1/5 second
1. I have read that for 50 mm lens, the speed should be faster? Should I up the ISO? I want all to be in focus hence F16.
2. I have it set to manual and use the green square in the centre of the specimen. Can I use the D750 to focus on multiple areas rather than just one green rectange area?
3. And would there be a way to adjust the light balance as a lot of the specimen is white card.
Much appreciate a few pointers, Denis