Photographing with glass base
17th Jun 2015 20:21 UTCMatt Courville
If one is happy with "mineral mug shots", then certainly the choice and control of the background has little to do with quality.
A good background creates an "environment" that emphasizes the shape and color(s) of a specimen without being distracting itself.
And a glass base gives you more flexibility in controlling this background/environment.
As Ed said, you can exchange backgrounds without moving the specimen, leave more or less space between the specimen and the background to blur or even "remove" the shadow.
You can create spots of light in the background at some distance without illuminating the specimen. It's easier to create smooth transitions from bright to dark with the background at some distance. Specimens that hover in space do look odd, and the reflections of the specimens on the glass actually help to make it look more "normal".
And not to be forgotten: You can still put whatever you want on the glass, even an ugly carpet. You don't lose much using a glass base.
There are two potential drawbacks of a glass base:
1. Its reflections illuminate the specimen, too, and depending on the position of the lamps, sometimes much more than a white cardboard would. In the beginning I was very worried about this and did not use a glass base and instead added an artificial background in post.
Later I found it to be much less of a problem than I had thought. In fact, when I did not use a glass base, I always had to add some illumination from below, otherwise the specimen would be too dark at its base.
2. If you make use of reflections, the specimens must be placed in the correct position on the glass, otherwise reflections will be oblique, and many specimens need a stand or another extra support to get them in the right - and unfortunately often instable - position. You also have to make up your mind on how to position the specimen before you put it on the glass, you can't rotate it freely in all directions.
Three examples, all done with the same setup, all with a glass base (the upper part of all backgrounds is still artificial/altered):
Plain window glass with "normal" reflections, blue background 10 cm below it.
Roughened non glare window glass (no special non glare glass) with blue backgrund 10 cm below it. One can really see the glass in that photo, it is nevertheless not distracting
Plain window glass like in the first shot with a white background moved up to about 5 mm from the specimen, resulting in a soft shadow.
A good background creates an "environment" that emphasizes the shape and color(s) of a specimen without being distracting itself.
And a glass base gives you more flexibility in controlling this background/environment.
As Ed said, you can exchange backgrounds without moving the specimen, leave more or less space between the specimen and the background to blur or even "remove" the shadow.
You can create spots of light in the background at some distance without illuminating the specimen. It's easier to create smooth transitions from bright to dark with the background at some distance. Specimens that hover in space do look odd, and the reflections of the specimens on the glass actually help to make it look more "normal".
And not to be forgotten: You can still put whatever you want on the glass, even an ugly carpet. You don't lose much using a glass base.
There are two potential drawbacks of a glass base:
1. Its reflections illuminate the specimen, too, and depending on the position of the lamps, sometimes much more than a white cardboard would. In the beginning I was very worried about this and did not use a glass base and instead added an artificial background in post.
Later I found it to be much less of a problem than I had thought. In fact, when I did not use a glass base, I always had to add some illumination from below, otherwise the specimen would be too dark at its base.
2. If you make use of reflections, the specimens must be placed in the correct position on the glass, otherwise reflections will be oblique, and many specimens need a stand or another extra support to get them in the right - and unfortunately often instable - position. You also have to make up your mind on how to position the specimen before you put it on the glass, you can't rotate it freely in all directions.
Three examples, all done with the same setup, all with a glass base (the upper part of all backgrounds is still artificial/altered):
Plain window glass with "normal" reflections, blue background 10 cm below it.
Roughened non glare window glass (no special non glare glass) with blue backgrund 10 cm below it. One can really see the glass in that photo, it is nevertheless not distracting
Plain window glass like in the first shot with a white background moved up to about 5 mm from the specimen, resulting in a soft shadow.
As Ed and Amir told a glass plate (I do not use plexiglass, because it scatched very easy) is a very usefull base for photographing minerals with different background colours. It's only a question of taste if you like a mirroring on the base of the specimen. One can create this mirroring with PS or Gimp, but this looks allmost artificial. The mirroring depends only from the angel between glass and camera, so you can do photographs with or without mirroring with the same setup! The most important and in my opinion the difficultest thing in photographing minerals is the illumination and the point of few of the specimen.
Some examples:
Double mirroring depends of the glass plate (not very aesthetic):
I made a special preparation of the glass, I have only a single mirroring:
The background of all my photos here on mindat is natural, only some photos have a generated background with Gimp.
Some examples:
Double mirroring depends of the glass plate (not very aesthetic):
I made a special preparation of the glass, I have only a single mirroring:
The background of all my photos here on mindat is natural, only some photos have a generated background with Gimp.
Kullu District, Himachal Pradesh, India