Digital Light & Color

I need to photograph a relatively large number of relatively small artifacts/antiques (glasses, statues, figurines etc.). It's to catalogue them. The images are for explanatory purpose and have no artistic value, but I still want them to be presented semi-decently. The ad-hoc 'studio' consist of either black or white large card background (hanged from the wall and gently folding on a table on which I will place the artifacts). The lighting is ambient and will be changing over the few days that I'll be doing the project.

Could anybody offer a brief advice as to how to go about it and what to avoid?

For example: I plan to use A-priority with average meter and the exposure biased by maybe a +/- 1.5 stops depending on black or white background and Auto WB on account on changing lighting conditions while still controling the DoF. Then I would like to batch process the resulting images minimally with some sharpening at the end, but I would like at least keep the backgrounds consistent: would Auto Dynamic Range and Auto WB in Levels and Colour do the trick in batch and how to adjust thresholds given the large areas of background (doe's it matter?) Perhaps some other combination of Transformations would be a little more complex to set but work better in batch?

Cheers!

p.s. Do I interpret the Threshold meaning correctly (in Auto Range/WB): low means small amount of highest value pixels are being ignored, high means that the larger amount of highest value pixels are being discarded before deciding on e.g. what the white point for the image is? On a philosophical note, I always had a problem with interpreting which way 'the Threshold goes'. Some time ago all (or at least most) of the threshold sliders were redefined to be more intuitive: slider to the left = no effect, slider to the right = full effect. It changed my life! :-)

I would consider the following.

Use a tripod. Set camera to manual mode. Set ISO to 100 (for best quality). Set the aperture to a value that you will keep consistent throughout the shoot.

Vary the shutter speed based on exposure needs which I'd recommend setting using a gray-card in the subject light. Set exposure (shutter speed) and white balance to the gray-card.

Use a remote shutter release, or the camera's short timer mode to minimize camera vibrations during exposure.

If you're familiar with using raw mode and the camera-supplied raw processor (or something like DXO PhotoLab), use raw since you'll have more post processing flexibility than shooting jpegs.

Ambient light is not your friend. Not only will the exposure be changing but you'll likely end up with odd mixed color-casts based on how the ambient light is reflecting off the surrounding surfaces. Also, the shadow harshness can change over time.

If you can light the scene through a diffuser (translucent white shower-curtains are cheap and effective) you'll will probably be better off.

That's my 2 cents.

Jeff

A couple of additional points:

I agree with setting the exposure with a gray card and leaving it the same for all photos taken in the same lighting.

Regarding lighting -- I recommend getting a mini ColorChecker if you don't already have one and including it in each image, next to each object. Then use Match Reference to undo the effects of different lighting and do the color correction. You might be able to get by just doing this once each time you change lighting but you would need to keep track of which color checker image goes with which images.

https://www.bhphotovideo.com/c/product/ ... _mini.html

Also consider getting some LED light panels and use them for lighting instead of ambient. There are also various tents made for product photography that surround the object with a uniform white background and diffuse the incoming light. Or you could improvise your own.

If f/16 doesn't get you enough DoF, you might need to focus stack.

The threshold in Auto WB relates to what percentage of the brightest (or darkest) pixels in the image to ignore. The idea being that you don't want to set the white or black point based on a few random pixels that happen to be very light or dark.