So, after shoting Eta Carinae Nebula (NGC 3372) with a wide angle lens, now it’s time to shot this target again, this time to inaugurate my new OTA with a close-up of those beautiful hydrogen clouds and giantic star clusters.
Not everyone knows, but Eta Carinae Nebula (NGC 3372) is four times larger than the Orion Nebula (Messier 42) and even brighter. Don’t misunderstand me. Messier 42 is incredible, but Eta Carinae is special. It is so complex, with a lot of star clusters, Hydrogen Alpha regions, dark clouds… and it’s huge! And the big red giant in its center? Speechless. This red giant totally deserves an dedicated post for its own.
The Astrobackyard also shooted this same target some months ago in Costa Rica and again recently in a Caribbean resort.
Man, I really hope to be that good one day! This guy is awesome!
Capturing Eta Carinae (NGC 3372) with a telescope and a DSLR camera
For the first time I was able to use my new OTA, a Long Perng S400M-C 66mm f/6 refractor! It is not an apochromatic refractor. It have only 2 elements, but for its price, it have an awesome color correction! It pushes a little bit to the blue, but nothing worrying.
As you can see, I’m not using autoguiding yet, and my camera adapter is far from the ideal. 😛
Nevertheless, the real issue is on the “camera attachment” side. I’ll write a dedicated post for this OTA, but in a few words… its focuser have one a SCT thread, and not a 2″ barrel.
Ok, I know, this target deserves at least 5 hours of integration. But I was so excited with the good weather and new setup that I reserved only 1 hour to NGC 3372. The rest of the night was used to try a lot of other targets, as I’ll post later.
Once my autoguiding isn’t working yet, I chose to stay with only 30 seconds per frame.
Processing the image
The amount of stars all arround NGC 3372 means that is really hard to proccess the image. It is common to over saturate the stars on the attempt to bring color to the gas clouds, or even lose details on the nebula when sharpening the stars.
My method here is to correct the black levels, then start pull the colors with curves. This process is repeated a few times. Again, thanks Astrobackyard for its lessons!
After that I reduce the size of the stars, or even cut them from the main image, putting all of them on a separated layer. This means I can process the “nebula” and the stars independently.
Try it yourself!
For those who want to try process a deep sky image, here is the link for the TIF file, as how it gets after Deep Sky Stacker. How about to send your version to me? 🙂 You can send me via Twitter, Instagram or Facebook.
Here is the final image:
Setup for imaging Eta Carinae (NGC 3372):
- Equatorial mount: iOptron CEM25P with a 2″ tripod
- Telescope: Long Perng S400M-C 66mm f/6 refractor
- Camera: DSLR Nikon D5000
- Autoguiding: No!
- 120x30s ISO 800
- 32 BIAS
- 37 DARKS
- 50 FLATS
The original frame was much wider, but a severe crop was needed. As my adapters not arrived yet, I’m using an 1.25″ T adapter, and it results in a lot of vignette.
I hope you liked! 🙂 Next time I’ll try more light on this nebula