Some basic considerations on the microscope photography of minerals, a beginners guide.

Here are some tips for those of you that would like to venture out into the wonderful world of mineral micro photography.
I'm aware of the diversity in financial resources different people have so I'll take different methods into account; photographing "hand held" through the microscope eyepiece, photographing using an adapter on an eyepiece of a binocular microscope and photographing using a trinocular microscope with a phototube.

Here's what you need:
1-a microscope, doesn't have to be an expensive one, either a binocular or a trinocular, although the rule applies here that the more money one is willing to spend the better results can be expected.
2-a digital camera with an optical zoom (very important, only digital zoom won't do!!), the same goes for this, it does not have to be an expensive one but quality helps..., and in case you use the phototube of a trinocular you also need an adapter to fit the camera to the microscope (one can design and construct ones own tube but there are also several manufacturers that offer standard and customized tubes.
3-a lightsource, the best option is a "cold light" (i.e. optical fibre) source, because in that case there is no excessive heat building up close to the specimen or your microscope (if you think such an installation would be too expensive it's also possible with ordinary spots, take care though with the heat!)
4-a software kit for editing photo's, these come usually with a new camera, for instance, with my Nikon came Photoshop and with my Canon cam- Photo-edit deluxe.
This is what you do:
1-You place the specimen under the microscope and look for the crystal or area you would like to photograph.
Look only through one ocular, this wil be the ocular trough which you'll make the photograph when working with a binocular.
When working with a trinocular it would be good to attach a notebook or a TV screen to the camera to be able to judge the right frame.
Take great care in positioning the object at an aesthetically appealing angle (a crystal photo from a 90 degree angle on it's top is hardly ever appealing).
Just tilt the object until you have a nice angle and turn it around until you capture it's most favourable side with as little strong reflections as possible.
Keep in mind, a low horizon (in this case the matrix on which the crystal rests) makes the crystal look far more impressive and make them stand out more against the background!
Also take great care in the composition of the image, make sure that there is an equal balance between the crystals in the image, one corner shouldn't be heavier as the other ones, and if it is (if that's your decision) move the specimen around until you have a "counterweight" somewhere else in the image (you can edit the composition with your software, more on this later).
Now make sure your specimen is properly lit.
For me the most beautiful results are achieved when you have an overall moderate lightsource and a strong lightsource from one direction (left or right, whatever makes the crystal look the most brilliant.
I usually take my pics in front of the window with daylight and boost this using a fibre light (cold light installation) from either the left or right side.
If you're ready with this you can move on to the next step.
2-Take out your camera and place the camera on the eyepiece of the microscope through which you were looking when you were positioning the specimen, when working with a trinocular or a binocular with a tube on one eyepiece the camera is already attached to the phototube.
Then zoom in using the optical zoom until the rounded edges of the ocular or phototube disappear, or further until you have the image you like (this will show on the little screen on the camera, important not to turn this off, this is where you should look from now on, looking directly through the camera won't work, or of course on the TV screen or notebook), don't use digital zoom though as that will dramatically decrease the resolution.
Switch off the flash.
Put the dial of your camera on the "manual" position and the macro position, when you are making Z-stacks one should set the dial to infinite (more on this later)
If you use an extra lightsource besides daylight you should switch the white balance of the camera to "incandescent" light.
If the background of the image you've chosen is very light compared to the crystal make sure you switch the exposure (exp. +/-) a few stops up (+), if the crystal is very shiny you can counter this by putting it a few stops down (-) or take back on the lightstrength (not too dark though!).
Now hold the camera in place on the ocular (this of course doesn’t apply to working with a trinocular scope or a binocular with a tube) with your left hand and turn the adjusting/sharpening knob of your microscope with your right hand whilst looking on your camera screen, turn it until the image on the camera appears as sharp as it can get.
Then hold your camera very still or make sure the camera is properly attached to the phototube and press the button to make your photo, when working with a phototube remote control comes in very handy, or if that is not available make sure you set the dial of your camera on time release (a couple of seconds will do to avoid the vibrations)
Try this a couple of times until you get a satisfactory sharp image and then go on to experiment with your lighting, camera settings and positioning of the specimen.
If you experiment a lot you'll quickly see your images improving dramatically, experience is the key here, as so often.....
When you have a couple of shots on your camera you can go on to the next step.
Use the RAW format on your camera as this retains the highest detail, after initial processing save the result as a TIFF format.
3-Edit the photograph using the software provided with your camera.
The manual will tell you what to do in order to be able to use the software the most effectively, of course I can't go into that any further here because there's so much different software around, I can say though that I'm very happy with Adobe photoshop augmented with Photo-edit.
Now on to the final step.
If you don't have any editing software you can skip this step and go on to the next step.
4-Save the pics on your computer in your documents and if you like print them on photopaper.
If this is all consumed well and everything works fine you can go on to making multilayer images and stack these using the software from Helicon or CombineZ (free!!), you'll be surprised what you can do with that, but that's for later, first get to know the basics well.
Well, that's about it.
I hope I've been able to show to you that you don't need a lot of fancy expensive equipment in order to make basic mineral photograph through the microscope.

Some small additions....

About lighting:

I found out that the best results are achieved when using different lightsources, preferably from the same spectral range.
Make sure you can control your lightsources individually, either by means of varying the actual intensity or by means of using reflective surfaces.
My latest photographs are made using up to 5 different lightsources in one pic: (northern) daylight from the window, coldlight reflected on white paper (if one uses coldlight directly on the specimen one gets very annoying and ugly reflections on the crystal faces), a Halogen light, a led light (also reflected, for the same reasons as coldlight) and an ordinary bulb within blue filter.
Like this you can experiment a lot, it gives you a lot of tools to be able to highlight all aspects of a crystal's faces although white balance will prove problematic sometimes.
Better would be to use several directable lightsources that have more spectral uniformity.
Also a light with a lens in front of it gives very nice results, that way you can minimize the area being lit so you can realy make the main object stand out from its background.
I also would like to stress the importance of composition, a sharp pic alone won't do.
Try to look for diagonals in the area you want to capture, nice diagonals can result in a very dynamic and exciting picture (they can be diagonals caused by the placement of crystals, of "claire-obscure" (=light-dark), of colour etc.
Always make your composition well balanced, object opposed to background/periphery, light opposed to dark, counterweight "heavy" colours (red, orange, yellow), perspective etc.

One more addition on the use of stacking software:

When using stacking software be sure to always take a shot of the nearest point of the specimen you want to have in focus first, then work down to the furthest point you want in focus, and upload it to the stacking sequence the same way.
Allways switch off the sharpening function and set the dial on your camera to infinite!
Don't allways go for the completely sharp pic as you will loose all atmospheric perspective and the result will be a very flat pic.
Also be aware that the true perspective will always get distorted when stacking, a perfect cube will appear as though the front of the crystal is narrower then the end taken proper perspective into account, much in the same way as with a technical camera.
Take care not to move the object, the algorithms in for example CombineZ and Helicon are quite powerful but they can't cope with too much difference between consecutive shots, resulting in a lot of noise.
Take control of too harsh reflections as most stacking tools can't cope with them resulting in annoying "halos".
Make also sure you use small increments between shots, especially when using high magnification, there's a logic to that: the higher the magnification the lesser your depth of field will be so the smaller increments should be taken between the shots, this goes v.v., the lower the magnification the deeper depth of field so the steps can be bigger.
Now to what camera to use.....SLR (digital mirror-reflex cameras) will give the best result BUT in stacking it is very good to be able to see real time what you are doing, taken that into account there are a number of very good options for compact cameras, very helpful is a camera that supports remote capture as you can control the proceedings from your computer.
Finally a short line on what gear I use:
For the basic method I use a Canon A540 combined with a cheap standard Byomic scope (with very good natural light coming through) with a homemade tube on the eyepiece, this still works the best for moderate magnifications.
For higher magnifications I use a Canon A640 combined with a Bausch&Lomb StereoZoom7 with a customized phototube (by Euromex).

One small note on artistic values....

The reason for making a mineral photograph can be to document a piece or a crystal, no more, no less.
On the other hand ones goal could also be to make an artistically pleasing picture.
In that case it might prove very helpful to study the paintings of renown masters.
For instance, when it comes to "claire-obscure" Caravaggio and Rembrandt are the masters, when it comes to diagonals building a composition Rubens is the one, for a strong and balanced composition one should have a look at Vermeer's painting and for excellent atmospheric perspective have a look at Gainsborough.
Apart from learning a lot about composing a picture one will have a great time looking at so much beauty!

Well, that's about it, hope to have been of some help!

Cheers

Harjo