More Moon Tips

The nearly full moon of October 28th, 2012.

When using a DSLR for Moon shots, many of the same film based tricks or techniques still work. 

A 100% full Moon is a subject fully lit by direct sunlight, so the Sunny16 Rule applies for an exposure starting point. The Sunny16 Rule states that for a subject fully lit by direct sunlight, a good starting point for exposure would be f/16 at the reciprocal shutter speed of the film's ASA (ISO). 

So, if using Kodak Plus-X B&W film, our exposure would have been 1/125th of a second (the reciprocal of the film's 125 ASA) and f/16. Kodacolor II at ASA 100 would give us 1/100th of a sec, but we would have still used 1/125th on those older cameras, it being closer to 1/100th than 1/60th was. We could have adjusted the f-stop a bit if we wanted to get the EV (Exposure Value) exactly the Sunny16 Rule for that film. Tri-X (ASA 400) would give us a 1/400th speed, 1/500th being closest to that on our old cameras.

We mostly likely would have bracketed exposures, taking one or two each above and below the recommended EV, perhaps in half stop increments. Of course, we were only doing this Sunny16 Rule if our exposure meter was out, or if we were just having fun going "old school."

Now, our DSLRs don't have any mechanical speeds (what would be the point?), but we do have full manual control available on most of them. And we have incremental shutter speeds, either in 1/2 steps or 1/3 steps. Our sensor sensitivities are changeable from shot to shot if we choose. We can go from an ISO (ISO replaced ASA) of 100 to 12,800 on some models.

So, when shooting the Moon (Earth's natural satellite), we set our cameras to manual and use the Sunny16 Rule as a good starting place for the exposure. Bracket a lot, it's not like we are burning through rolls of film. Don't get fooled into thinking we need multi-seconds long exposures. That will merely burn out our exposure, giving us no useable data.

Another thing we may need to bracket is our focusing. Depending on our camera, lens, and focus system, we may not be able to find true infinity with autofocus. So, switch to manual. And when you get a clear image on your viewscreen or in your viewfinder, take that pic, but also tweak your focus forward and back a tiny bit, thus increasing your chances of getting a sharp image.

Finally, even though you are using fairly fast speeds (compared to other low light situations), brace yourself. Tripod, monopod, fencepost, beanbag, etc...

Now, even if your image looks small on your computer screen, you probably have enough sharpness and image detail to crop in, giving you a virtual zoom. In the photo above, I shot at 300mm (450 equivalent compared to 35mm). I enlarged it via my image processing program to about a 1000mm equivalent.

Enjoy your digital Moon shots!