Tag: Rosette nebula

NGC 2237 Rosette Nebula

Rosette Nebula is a giant cloud of hydrogen gas. The gas is ionized by the star cluster located in the middle and therefore emits the light. Circular shape and the color correspond to the name – the rose. The cluster in the middle can be observed even by using small telescope, but the nebulosity is very dim, therefore in order to see it, one would need perfectly dark sky and very large telescope with low magnification. It’s definitely easier to photograph the nebulosity. My previous photo was done through the narrow band filters, which suppress the light pollution and increases the contrast of the picture. Now I tried it with normal one shot color camera and I must conclude that it went quite well.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure16x300s, Gain 94, bin 1x1,

NGC2237 Rosette nebula

Another place where the stars are born is called Rosette nebula. It is a cloud of hydrogen gas, located 5000 light years from Earth in constellation Monoceros (unicorn). The diameter of this nebula is 50 light years.

This time I processed collected data by two different ways. Basic data are three monochromatic pictures captured through narrow band filters: Hydrogen alpha, Oxygen OIII and Sulfur SII.

First technique is called Hubble pallet – natural color of H alpha is red, but it’s inserted into green channel, oxygen is blue, therefore ends in blue channel and sulfur is even more “red” than the red color, therefore lands in red channel. After many different post-processing steps the final picture looks like this:


Second technique is more realistic for the human eyes and brain, and requires pixel math. H alpha is red, SII even more, therefore the combination of this pictures (SII + 0.8*H alpha) will end up in red channel. Green channel is a combination of 0.075*H alpha + OIII. Finally blue channel is just OIII.


I am quite curious which picture you like more…