1. Atmospheric conditions
An important consideration regarding site conditions for lunar photography is atmospheric stability, or seeing. The finest of equipment is meaningless if one attempts to shoot in less than ideal conditions. The slightest wave of atmospheric turbulence distorts and blurs the moon's surface. Hence, the shorter the exposure time, the better. Obviously, seeing becomes more of an issue with greater magnification.

I never shoot in less than (near) ideal conditions. Being a perfectionist, I consider it a waste of good film to shoot under poor conditions. I only shoot when seeing is equivalent to an 8-10 on the Pickering scale. For those disappointing nights, I just relax and observe neat details on the moon.

2. A solid, stable mount
The second-most critical element to perfect lunar photography is a stable mount. Perfect seeing will never compensate for a mount that shudders and vibrates every time you breathe. Just tripping the shutter can be enough to ruin a potentially good shot if the mount is too weak. Best advice: You can never buy a mount that is "oversized" for your scope. The beefier the better. I use an Astro-Physics 600E mount: portable for traveling, solid enough for lunar work.....and best, I can lift it!

3. Camera
I admit straight out that I am a dedicated Nikon fan. An all manual camera is preferred, especially in colder climates. Most of my shots were taken with a Nikon F body. However, some shots were taken with my Nikon 8008 body (which has an excellent, bright viewing screen).

The main thing with camera bodies is that you want a mirror lock-up function if possible. Mirror lock-up is mandatory prior to exposure in order to reduce mirror flop vibration. The Nikon F series cameras have this locking function.

However, the Nikon 8008 does not. To get around this, I employ the old "hat trick" method. Place a large flat-black object in front of the lens, trip the shutter (on bulb setting), wait for the equipment to settle, then expose by removing block. Replace block after proper exposure, then release shutter.

Oh yes, always use a cable release.

Focusing:
I had great difficulty focusing when I first began lunar work. I tried using an eyepiece magnifier (2x) that attached to the viewfinder. While this helped, the image was somewhat dark and still difficult to focus. Currently I have found that the Nikon DW-2 (6x) focusing magnifier is the answer I was looking for. Its bright screen and good magnification allows for excellent critical focusing! This device replaces the pentaprism on the Nikon F series cameras.

If you don't have access to equipment like this, there is another option: knife edge focusing on a star. You can find a detailed description of this process here: http://web2.airmail.net/capella/myknife.htm

4. Film
Film carries a somewhat overrated importance in lunar photography. My seemingly indiscriminate use of a variety of unconventional films (TMax, Fugicolor Reala, Kodachrome) suggests that other factors are of greater importance. I shoot whatever is in the camera at the time.

If told to choose one film, however, I would pick TMax 100. Why? Good latitude. I want the most grey scale possible in the shot. Grain isn't a critical factor for me as the image is displayed via the internet. Screen resolution limits the visible grain on most medium ASA speed films.

5. Eyepiece projection
I occasionally use eyepiece projection for achieving larger scale. I use an eyepiece projection adapter sold by Orion. They are relatively inexpensive. The major drawback to eyepiece projection, unless you use a specialty eyepiece, is field curvature (where only the center of the field is crisp while focus drops off rapidly away from the center).

To calculate image scale and focal ratio use the following formulas (all measurements in millimeters):

1. Projection focal ratio (PFR) = Telescope focal ratio (FR) x magnification (M)

2. M = Eyepiece (EP) to film plane distance - EP focal length (FL)

EP FL

For example: Let's calculate the magnification if we used a 20mm eyepiece projection device (assuming that we are using an f/7 scope).

M = 80mm - 20mm

20mm

M = 60mm

20mm

M = 3 power

To calculate what projection f-ratio the scope is working at:

PFR = 7 x 3

PFR = 21

The shots I have taken using the 10.5 mm Televue Plossl results in a focal ratio of 45 with the 6-inch, f/7 scope. For f/28 shots, I used a 17.5mm Televue Plossl.

I have also utilized an AP Barlow (2x) which effectively doubles the magnification (or making the 6-inch f/7 scope work at f/14). On photos, such as the Straight Wall and Eratosthenes, I used a TeleVue 5x Powermate--a neat alternative to eyepiece projection, allowing me to work a 130mm f/6 scope at f/30. However, there is still the problem of field curvature.

6. Exposure
I am fortunate enough to have a camera (the 8008) that has an extremely sensitive and accurate meter. Even using eyepiece projection, I am able to meter with precision. I simply switch camera bodies after metering if I am shooting with the Nikon F.

Realistically, most people aren't as lucky to have a good meter on hand. There are two options available. First, there are lunar exposure tables that can be referenced (Covington's Astrophotography for the Amateur has these tables). Second, if you hate math, there is always the mass bracketing technique--and hope one of them turns out.

7. The final product
I use both traditional darkroom processing (enlargers, paper, and chemicals for those of you computer nuts) as well as digital processing. I like the image result in the darkroom better than digital, but no doubt it is my lack of experience with digital rendering that hampers the end result.

For digital, I scan my negs/slides using a Polaroid Sprintscan 35 Plus (superb!). Adjustments are done to the final image in Adobe Photoshop. Typically three adjustments are necessary: a sharpen routine (absolutely); contrast increase; and brightness increase. Sometimes I play with the burn tool (in the darkroom, I always burn and dodge) to enhance some lunar surface characteristics.

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