Telescope Reviews: Printable, mirror-reversed moon map?

Andy,

If you aren't able to find what you're looking for ready-made, you might find the freeware Lunar Terminator Visualization Tool (LTVT) more suitable for your purpose than VMA. Whether it's as easy to use, I don't know; but it's certainly more flexible.

With LTVT you can use any of the textures provided with VMA, as well as many others freely available from the USGS Map-a-Planet service, as well as (as you suggest) actual photographs of the Moon taken by yourself or anyone else. The software will automatically supply the correct (and correctly spelled) labels, and with a little practice you should be able to produce quite professional looking results. I'm no expert on VMA, but LTVT gives you total flexibility over what features are labeled and with what font (including size and color). It also places dots unambiguously identifying what feature is being labeled, and (if you wish) can draw circles indicating the feature boundary.

The name and position information is stored in something called a "dot file", which is a simple text file that can be edited with any text processor, like Notepad or WordPad. One way to control what is labeled is to use a text processor to "flag" the items you want in the dot file (or in a spare copy of it). Setting the Size Threshold to -1 will then overlay (and label) just the features you've flagged. Another, and perhaps more educational way, is interactively choose which features should be labeled by pointing the mouse at whatever looks interesting to you, right-clicking and selecting "Identify nearest named feature." You can then, if you wish, right-click a second time and ask the software to "Label nearest dot," and the label will be automatically supplied. Hopefully you'll learn something about the feature names in the process. You can also manually add non-standard names (and their positions) to the dot file if you want those names to appear on your charts. And you can also add a longitude-latitude grid if you wish.

In addition, you can set the libration (the lon/lat of the map's center point) to (0, 0) -- which is the standard for lunar mapping, yet something I believe you will be unable to do with VMA.

To use actual photographs, rather global textures, you need only to correlate any two features visible on the photo with their long/lat positions on a standard texture. As with textures, LTVT can automatically re-map the photos to zero libration, although the results may not look as satisfying (because of an absence of data around certain parts of the limb). You can also automatically label images that have non-zero or even exaggerated libration to bring out details near the limb.

The size limitation mentioned by Roger might seem an especially serious show-stopper for LTVT since it draws only in a fixed 641x641 pixel window. However it has a precisely adjustable Zoom capability and an equally precise X-Y "Go to" capability which can set the center position in terms of fractions of the lunar radius. If, as a somewhat arbitrary example, you set the Zoom to 4, it will take exactly 4 of the on-screen windows to span the lunar diameter, meaning that the entire Moon will fit exactly in a 4x4 array of 16 tiles with a total width of 4x641 = 2564 pixels. The edges of these will be at the Moon's center, 0.5 of the radius and 1.0 of the radius; so the centers are at 0.25 and 0.75 of the radius. Thinking of this as a grid pattern, you can quite easily use the X-Y Go To function to correctly center the simulations to produce exactly the 16 tiles needed to cover the Moon. They will fit together seamlessly and can be easily butted together with Photoshop or the Gimp or nearly any other photo processing software. The process may sound overly complicated, but this is no harder than what imagers do to produce full disk mosaics. In fact it's much easier because the tiles fit perfectly.

You don't, of course, need to use a Zoom of 4 -- you can use whatever you need to get the final pixel width you want for the full lunar diameter. I should mention that there may be some problem with labels that span tile boundaries, but this can be solved by generating tiles that overlap. Again, the overlaps will mesh perfectly, so aligning them to make a multi-megapixel mosaic is quite trivial.

I don't realistically expect anyone to follow through on this -- buying the S&T Field Map is easier and more efficient -- but if you want something with custom labels, the capability is certainly there.

-- Jim

P.S.: you'll find image inversion (left-right and/or up-down mirror inversion) under Tools...Cartographic options...

P.P.S.: if you use LTVT to make a useful set of printable images, and they're under 10 MB each, you might consider posting them for download on the LTVT Wiki so that others won't face the problem you did.