I have been an avid mineral collector since I was young and I spent some time learning how to photograph them properly. With the right specimen and setup these can look absolutely stunning. I will share a few of the things I've learnt.

There are no hard and fast rules and all of those below will be broken in some circumstances to great effect.

1. Find a good specimen

This is somewhat subjective of course; but there are important things to look out for when choosing a mineral specimen. Many crystals are damaged during their growth and this natural variation gives them their beauty; but avoid any obvious damage caused when removing the mineral from rock (more posts later). Look for crystals with nice sharp edges and smooth faces as these will catch the light nicely.

2. Presentation

The angle of presentation should be chosen carefully; avoid flat images where the object appears dead centre; facing the lens. Introduce some rotation and tilt; stick the specimen down using mineral tack if needed (slightly better than blu-tack).

You can opt to use an aesthetic looking stand as I often do. I have some custom produced perspex plinths with bevelled edges; as these look great. Using old or scratched plastic is a bad idea as the macro lens will show it up (although minor scratches can be airbrushed out).

The background should be simple; white or black. Using a reflective surface to mount the mineral can be really effective (I use black acrylic); but be careful not to scratch and mark the plastic with repeated use.

I have occasionally looked to up the ante even further by creating a "halo" effect around the object. This was done by suspending a white paper disk somewhere behind and above the specimen (adjusted manually using the live camera feed) to cause a reflection from the black acrylic (this requires a large sheet of acrylic so that there is enough space behind the mineral for the reflected disk).

3. Camera and Lens

Use a decent camera and a macro lens. I use a 100mm focal length Nikon macro lens on a Canon 550D DSLR camera. The camera obviously controls the quality of the image quite strongly; not only through overall resolution but through the flexibility to adjust the camera settings to optimise the image for the particular setup. The use of a macro lens is essential to produce the detail seen in some of these images. However, a regular lens can also do the job well.

The camera should be setup on a good quality tripod. Stabilising the camera is very important as we will soon discuss. The ability to remotely control the camera via a USB connection also comes in very handy.

4. Lighting

After the camera, the most important aspect of mineral photography is lighting. This has taken me the longest time to get right; very fiddly and somewhat costly. I will try to cover all the mistakes I've made but no guarantees...

First off; we need a good overall diffuse lighting onto the specimen. I use a large LED grid light used by professional photographers because it has high CRI, intensity and a good neutral white colour light. Using yellow light or poor quality bulbs will negatively affect your image; the best mineral pictures have a very sterile light colour. All the interest of the image is in the inherent beauty of the object. Diffusing the light is important (I use a diffusion filter which comes with the light, basically just a sheet of tranluscent plastic).

I tend to place this light above the specimen; fairly close, and with an intensity which illuminates the entire specimen. Now if you take a photo you will get a great result; but it can be better!

We need to add spotlights; which are small pointlike sources of light used to highlight various parts of the mineral. Mostly; I use these to create reflections from crystal faces. If you look closely at some of the images you will notice that several non-parallel crystal faces are illuminated (sometimes even with different colour light). I achieve this using several additional LED grids placed very carefully around the specimen. This process is the most laborious of the setup; and it really helps if you setup up your DSLR to produce a live image on a laptop or PC screen within view as you adjust the lighting.

Make sure the spotlights are as dim as possible; so the reflected light can be seen, but it doesn't saturate the camera (most crystal surfaces have striations or features which add depth and detail to the final image and we want these to be visible despite the spotlightling).

5. Taking The Picture

Just click the shutter, no?

Not quite. Because of the use of a macro lens; the "depth of field" is very shallow. This means that only a small depth (few mm) of the object is in focus. This image would be mostly blurred. We can adjust the in-focus area of the object through the f-stop of the lens.

This is where the use of a good DSLR and macro lens is important. Canon produce a software for controlling the camera from a PC or laptop; you just need a USB cable. With this software you can control the f-stop of the lens and take an image without touching the camera. This is important for two reasons;

• Controlling the f-stop allows many images to be taken, each with different f-stops. Each image will have a different depth of the object in focus; you should make sure that the set overlaps so that none of the depth of the object are missed.

• Following from the first point, not touching the camera retains stability of the image throughout the entire process.

Now we have a bunch of images of the object; each with a different part of the object in focus. We need to combine them into a single image using a process known as "stacking". This is best done by professional software (I use Helicon Pro); which in some cases may require a small subscription fee.

Once complete; the stacked photo should look sharp. You may notice some artefacts in the image caused by the stacking algorithm. This is particularly true around parts of the crystal that scatter or reflect a lot of light.

6. Fixing Up the Image

The final step is to post-process the image. There are many things I commonly do at this stage; and a lot of it comes down to preference or trial-and-error as to what looks best. I use GIMP on Mac for editing.

• Cropping : Crop the image so the specimen takes up most of the space. Cropping asymmetrically can "guide the eye" in the image. Keep the main feature of the specimen near the centre.

• Airbrush out stacking artefacts: Get rid of those irritating haloes around the sharp edges of crystals using the brush tools.

• Adjust the colour histogram; this sorts out the lightness of image (don't leave it looking dull). If the image is saturated we can't recover the detail in those regions; so its always better to take a duller image and correct it by brightening, than accidentally saturating any areas.

• Selective blurring : If the specimen has very aesthetic focal spots such a big colourful crystals; consider applying a light blur to the matrix or outer portions of the specimen to draw attention to the focal point. You can also selectively dim region of the image (for example around the base of long crystals) to achieve the same goal.

• Remove pubes and dust from the image. There are always a few hairs or dust particles strongly scattering the light, these can be removed using the brush tools in GIMP/Photoshop.

7. End!

That was longer than I thought! I will follow this post up with some more details and further expansion on some of the things I've mentioned here.

Checkout the results of this guide in my Gallery.