M42 Inverted

M42, the Great Nebula of Orion
Sketch and Details by Serge Vieillard, translation by Frank McCabe

M42 before sketch inversion
Sketch by Serge Vieillard

Inverted sketch of M-42

It was January 3, 2009, on a beautiful and cold (- 7°C) evening in Royal Port (78) and I was with the buddies of the club. The crescent moon was bright and interfered somewhat with the observation. However, I want to try out the technique of color application by what I call filters interferential. M42 passes to the meridian line and lends itself magnificently to the test.
T400mm-c (Obsession Telescope) is equipped with Ethos 13mm ocular. A first vision without filter makes it possible to place with the lead pencil the star field and the various luminous zones of nebula. Then the use of a filter OIII makes the object more filamentous and accentuates the thinner extensions. These additional details and these appreciations are drawn with the purple pencil. (Upon inversion this will provide the green shades commonly see at the eyepiece)
Lastly, the filter H-beta radically changes the vision into literally revealing invisible zones under the current terms, like the broad wing on the left of the drawing and the fine line wing which borders its green neighbor, here completely extinct by the filter. On the other hand M43 is almost invisible with the OIII whereas it is detached well with H-beta. These additional details are drawn with the green pencils which reveal the reds and pinks at the eyepiece after inversion.
After passage into negative and treatment of the colors, one obtains this result which I describe as L, R (H-beta), V (OIII).