Technically, anything more than 10x magnification qualifies as Microphotography. Microphotography is a fairly specialized field, as you can imagine, and one might be inclined to think that it’s best left to the researcher, professional or hard -core enthusiast who has plenty of $$ to spend on an expensive microscope-camera setup.

However, if one is willing to settle for less than the very best and latest equipment, there are plenty of options for the stubbornly dedicated amateur who wants to put together a microphotography kit for under $100, including the illumination. The secret? Old College microscopes that appear with startling regularity on eBay. You can get a nice new microscope for about $250 -$500 these days, (mostly imports from China and India, and pretty decent optics), but that’s not being thrifty and adventurous.

Also, many of the new telescopes are made of lighter materials – they are designed for optical quality, and for the most part they are expected to be used with lighter digital cameras with a C adapter, or “in-tube” digital USB cameras that fit into the viewing tube in place of the ocular (eyepiece) and are connected to a computer display. Fitting a full size manual or film or even digital SLR camera on these newer telescopes can cause problems with vibration and shake. Older telescopes were constructed solidly. They generally feature all metal construction and this makes for a rigid camera platform.

I’d look for the full size ones that have been pulled from Colleges – stay away from the toy microscopes that have low grade optics and are 7 inches tall. The full size microscopes are HEAVY, and are about 12-14 inches tall. They weigh about 8-10 lbs. The weight is needed to support your camera… most colleges these days are pulling their Monocular microscopes in favor of the Binocular or Trinocular scopes that have built in illumination and can take a digital camera attachment. Too fancy for me… and too expensive for an amateur looking for the cheap, affordable microphotography solution.

College surplus monocular microscopes are ideal – they generally come with an 10x eyepiece (ocular) and a couple of objective lenses (generally 10x and 40x) – this gives a 100x and 400x magnification. Its important to look for a microscope with a 25mm outer diameter tube and 23mm diameter eyepieces. Luckily, microscopes were standardized early on, and unless you choose a really old antique from the 1900’s you should be okay. If you’re lucky, you might find a complete microscope, with eyepiece, objectives, stage, condenser, spring clips, fine and coarse controls AND illuminator.

Most microscopes come with some sort of illuminator – its good to have a electric source for consistent lighting needed for photography. Also, it isn’t sufficient to have lighting just on the underside – we need a bright beam focused ON the stage as well. A halogen table lamp serves pretty well for surface lighting.

I was lucky to find a German made Wolfe Wetzlar monocular microscope with a 15x eyepiece, 10x and 45x objectives, a decent Abbe condenser and an electrical illuminator with a blue filter and on/off switch. The combination gives me a 150x and 675x magnification. However, at 675x, the field is pretty dim, even with the electric illuminator.

More recently, I picked up a Japanese-made Propper microscope for a very reasonable price, (less than $20) thinking that I could just scavenge the optics off of it and throw away the frame… the Propper has a set of fine British made Cooke-Vickers Microplan objectives – a 5x, 10x and 40x, and a zoom eyepiece (10x-15x-20x), so I will just clean it up and use it for general microscopy.

Ideally, one would want 40x (or 50x), 80x, 100x and 150x magnifications for photography. Remember that high magnifications are very hard to illuminate. About 150x is easy to handle in terms of lighting. To get these magnifications one would have to keep keen tabs on eBay or other online sources for cheap eyepieces and objectives – don’t worry if it’s DIN or JIS – see the note below.

Surplus Shed is a good online place to pick up additional objectives and eyepieces. They stock lots of very reasonably priced objectives from India, and ship quickly at low cost. I was happy with their service (no, I’m not affiliated with them in any way, just a happy customer). Another place that stocks used microscope objectives and eyepieces at a reasonable prices is NY Microscope, a school supplier. They generally have other microscope parts as well, in case you want replacement parts. I haven’t bought anything from them yet, but they were quick to reply to my email inquiry, so thats a very good sign.

Here is what you can add over time, unless you get lucky and get them cheap like I did with the Propper – 10x, 15x and 20x eyepieces and a 4x and 20x objectives. Fit the microscope with the 4x, 10x and 20x objective and put the 40x and higher power objectives away, since you wont be using them much. Don’t waste your money on a 100x objective, unless you got it with the microscope – they’re usually oil immersion objectives and require that a drop of type A oil be placed on the slide between the objective and glass. This is a pain. The oil apparently becomes part of the optical system gives the high magnification in conjunction with the 100x objective and eyepiece.

At least one of the eyepieces should be a widefield (WF) if possible – these are designed for wider viewing fields and also provide greater eye relief (image is formed at a little distance above the top of the microscope eyepiece). This eye relief is for use with glasses, but serves us even better in photography since the camera will “see” a bigger field than with a normal eyepiece where only the center of the microscope field is imaged on the film.

To complete the setup, I also purchased a camera to 25mm microscope tube adapter. One end is a T-mount thread and the other end clamps on to the tube. The adapter tube comes apart in the middle – the smaller end which goes on the microscope body receives the eyepiece, and the other end receives the camera. They generally go at $30-35 plus shipping on eBay, but you can usually pick up one new for about $20 from SurplusShed.

Get a few glass slides, or even an old UV camera filter, drop it on the stage with a bug or leaf or whatever, get the illumination going, mount your trusty camera loaded with 100 or 200 film, and you’re set. Exposures will be long – 2-5 seconds at lower magnifications, greater for higher – reciprocity failure will happen anyway, so don’t worry – easiest is to set the camera on B, and give it a good 5 or 10 second exposure. The camera is mounted solidly, but since it’s all metal to metal connections, anything that will reduce vibration is a good thing. If possible, use a camera that has a mirror lockup. An old OM-1/OM1n is ideal since it has the mirror lock-up feature especially if it has a working meter. If your camera does not have mirror lockup, don’t worry about it. Minimize other sources of shake as far as possible, and use a cable release.

Note: A word about DIN and JIS – one is the German Standard, the other Japanese. The diameters, thread pitches etc are exactly the same. However, when magnification is stated, the DIN standard bases its calculation on a 160mm microscope tube length while the JIS standard uses 170mm tube length as the basis. In both systems, the standard eyepiece diameter is 23.2 mm, generally stated as 23mm. (there are 30.5mm diameter tubes as well, but they are much newer, and not cheap, so we will not get into that discussion). Now, no matter what the sellers say, the 2 systems are completely interchangeable – although magnification will not be correct – it will differ by approximately 10%. For our purposes, that’s not important.


text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.
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