Vixen 140mm Neo-achro, 2" AP Maxbright diagonal, 40mm Orion Optilux, 35mm, 30mm, 18mm, and 15mm Ultrascopic/Ultima, 28mm & 20mm ES 68, 19mm TV Panoptic, 5.5mm Meade UWA, 2.4x 2" Dakin barlow (prototype barrel),1.6x Antares barlow.
--------------------- --------------------- "Nothing exists but atoms and empty space. Everything else is opinion." Titus Lucretius Carus 99-55 B.C.
Quote:I'm familiar with those novelty 3D posters, and used the same technique to study stereo pairs of aerial photos back in the day. But that takes two eyes. Are you using a binoviewer with your scope?
Thomas Watson - Author of Mr. Olcott's Skies. Available in paperback and ebook formats. Weblog: Under Desert Stars
Mardi 4" achromat, ETX-70, 8"cat. Whitepeak Lunar Observatory Website
Quote: This is an example of an optical illusion called "reversible perspective" typified by what is called a "Necker Cube".
Cactus Patch Observatory / 14" LX200
"The four points of the compass be logic, knowledge, wisdom, and the unknown. Some do bow in that final direction. Others advance upon it. To bow before the one is to lose sight of the three."
Quote:Mardi: You're back! YAY!!!!I'm familiar with the illusion, but I've never actually seen it. Not on the moon, and not in your photo. And I've tried! But, I *have* seen it in Mad Magazine, when they used to have the "Mad Poiuit", a 2-prong - no, 3-prong optical illusion.Which makes me agree with Hank about Escher's work.
Brian S. Johnson
All Terrain Z10 http://tinyurl.com/ouxfsyu with refigured primary, 63mm Protostar secondary.
Carol Lakomiak, Tomahawk WIWriting Sky at Night magazine's astrosketch page since June 2009Moon Sketch TutorialSun/DSO Sketch TutorialCN GalleryPhoto Gallery
The opinions expressed herein are solely mine as an amateur astronomer hobbyist & consumer. Information herein was correlated from experience, discussions with others, & research from multiple sources freely available at time of posting. All reasonable care & skill was used, but no warranty is made as to accuracy, & liability cannot be accepted for errors/omissions. This is for information only and not intended nor implied to be a substitute for professional advice.
10" Sumerian, Webster D18, solar scope, small 'frac, Vixen Foresta 8x42 Take action against Light Pollution. Together we can make a difference.