Here is a couple of pics of my first moon phto. I built the 400mm F5 lens. I admit to just missing perfect focus. But I didn't have a split screen in my DS yet. FOV would be like a 600mm in 35mm film.
[IMG]http://i630.photobucket.com/albums/uu25/wildlifephotog/400mm-lens.jpg[/IMG]
[IMG]http://i630.photobucket.com/albums/uu25/wildlifephotog/400-moon_filtered-web.jpg[/IMG]

Source of the word cockpit.
http://www.aerospaceweb.org/question/history/q0064.shtml

I've been using Michael Covington's figures for years with no problems. His Astrophotography for the Amateur book is a solid read for budding astro shooters.

BTW. It makes a huge difference where the moon is in relationship to the celestial equator. The closer an object is to the celestial equator, the shorter your exposure has to be. A 28mm lens can be pointed at the pole star, which is 90 degrees from the celestial equator, for as long as 90 seconds with no apparent star trailing.
[IMG]http://i630.photobucket.com/albums/uu25/wildlifephotog/specs.jpg[/IMG]

At 200mm you can go as long as 1 second for critical work, 4 seconds if some blur is acceptable.
Full moon, start with f16 and 1/125, and make adjustments as needed.
The red ring is chromatic aberration caused by the design of the lens.
Try stopping down when shooting very bright subjects.

Ponzo is spelled correctly. It is a dressing/marinade.
Google ponzo dressing/marinade.

Be prepared to do some major white balance adjusting. Otherwise, you will have the strangest colors in the photo. I use this kind of glass on some of my scopes for shooting the sun.

I was just at a gallery showing of David Fitzsimmons work. He is one of only 5 north american Sigma pros. He uses round frames for almost all his 4.5mm fisheye shots.
http://www.enaturalist.org/component/option,com_jevents/Itemid,19/catids,77%7C79%7C78/day,07/evid,130/month,03/task,icalrepeat.detail/uid,1253805209evt12/year,2009/

They really work well.

The 90/2.5 was designed to use the extension tube to give 1:1 at 90mm.
The 2X converter gives 180mm at 1:1. But there is some loss of resolution in it's use.

There are many VERY good astro photographers on Cloudynights.
I have learned much from just reading their posts.

Here is a link to the Registax software.
http://www.astronomie.be/registax/html/download_v4.html