JF: If you have a suitable tree in the front yard, mount a sheet at a convenient angle. Then beam your scary images to impress those trick or treaters. Put a little outdoor speaker behind the sheet for sound effects. Lastly, mount a suitable located videocam and post the best scenes to YouTube.

Reminds me of those nights 70 years ago when I spent a summer on a farm and had to go to the barn in the dead of a moonlit night for some reason or another, now forgotten. So your shot is more than just a picture. Thanks.

JF: Moonlight, while it illuminates, is different from sunlight. If you have access to a garden with several different hued flowers, then on the next bright moonlight night look at the flowers. While sunlight has all wavelengths from red to violet, moonlight is reflected sunlight so its wavelength span is different.

Have you tried Photoshop to correct the offending spots?

I meant two titles.

A quick look into the Apple Book store shows to titles by Kingslake. The newest is $109, but you can get a sample which is 111 pages (the first 35 or so are the preface kind).

I want to thank everyone for the very helpful replies. To extend a bit. I long ago read a short article in which the author opined that some if not many lens abberations could be averted were lens ground to elliptical curvatures instead of spherical. In photography we are partly saved by film emulsion grain size and now digital pixel size, but astronomers were not as fortunate. Commentary invited.

Long ago, I read an article on the Zeiss Tessar lens. It was developed in Germany before World War Ii and was said to have admirable properties. Is there a lens history article somewhere that tells how lenses developed and what optics problems were sought to be solved. I am an old gezzer with lots of time on my hands. Oh my, its getting late; I better get out to sprinkle the garden (i.e., three plants).