Starship Asterisk*

True color image of the Cirrus nebula (NGC6995) , taken with my 94mm f/4.4 Apochromat and an ASI294MC Pro using a VIS filter for the stars and Dualnarrowband for Ha and OIII. Ha and OIII are weighted in the linear space according to the relative sensor sensitivities and then given those colors, whic...

Two Comets and a Flaming Star The Comets C2022/E3 (ZTF) and U2 ATLAS in a rich starfield in Auriga with hte open clusters M36 and M38 as well as with the flaming star nebula. Taken with Pentax K3 Mk III, Pentax FA 77mm f/1.8 limited at f/3.5, 15x120sec @ISO400. Stacking and processing in PixInsight....

You misunderstand me. The wavelength of Ha contains no green or blue signal from typical display primaries. It can only be represented by red. Imperfectly, of course. There are emission lines from different species that we can see as different with our eyes (say, with a gas tube) that cannot be ren...

As my intention is not to have any misleading discussions here, I would highly appreciate that one of the moderator team would simply place my post back to the submission thread, because my main intention was to submit this image and its explanation for APOD. By the way, Ha - for example - isn't eve...

And this consistency is defintely beneficial, as it gives us an instrument to avoid NGC7000s having all colors from orange to purple, just to the individual photogapher's taste. But believe me, if you display my Ha color on a monitor, it is measurable, that this specific color does have the least de...

Hi Chris, it is not color, it is perception, which is physiological! Thats why you worked in a color PERCEPTION lab. I, however, am still working in a color-measurement and color/emitter calibration lab. You will never observe e.g. a monochromatic yellow as a different color or variety of colors, un...

The problem is that "color" is physiological, not physical. There is no "correct" mapping for that which we cannot see. Hello Chris, there I have to strongly disagree. For sure, perception is physiological, but color is NOT! Even, there is a clear relation between the primary st...

How Narrowband emitters really do look like... This image shows a comparison of conventional color rendering (left side) and the physically correct color rendering (right side). If you have ever observed M42 in a larger aperture instrument under good skies, you will remeber the grey-blue greenish t...

Hi, my name is Markus and I am into astronomy since childhood. Having my first job enabled me purchasing my first telescope back in 1998, a 4.5" newtonian. As I did photography already for more than two decades, I more and more started trying astrophotographical work. First on chemical film wit...