Gabriela reprocessed in HOO colours from 0riginal Data captured in 2021
Eta Carina Nebula 2021
Eta Carina reprocessed in HOO colours from 0riginal Data captured in 2021
IC 2944 Nebula
IC 2944 reprocessed in HOO colours from 0riginal Data captured in 2021
Short exposure of the Orion and Running Man nebula
Testing out the camera with a 40 minute exposure of Orion
Finally Imaged Tarantula Nebula-NGC2070
After many years away from the hobby I decided to upgrade the obs, and my gear and here is the first image with the new gear.
Horse Head Nebula
I have tried in the past to get a reasonable image of the horse head nebula, but have never had much success due to the light pollution and lack of experience.
I wanted to take advantage of the relatively nice weather and started trying to image the Horse Head Nebula. Light pollution has become a problem in my area, and after several terrible results in the past using a colour camera, I decided to splurge and purchased a second hand QSI 583 mono camera with filters.
Man I should have done this sooner. This is the result of first light for this camera. The image below is not fantastic and is only monochrome but I am very happy with the amount of detail I can see in this test exposure from a suburb that is heavily light polluted now.
It was windy so the Active Optics unit was working overtime and there was a very bright moon very close to the target, so I used an Astrodon Ha filter. This is the result of 4×10 minute exposures through an ED80. There are many issues with the image for the fussy peeps, but it taken in difficult conditions with new gear and much cussing, as I was working out how to get it all working together. I can see more detail in the nebulous regions then I have ever managed to capture before. In the past the cloudy region around the horse head always looked plain and featureless. This time I have picked up more detail.
I now want to capture much more data as 40 mins is no where near enough for this faint object, but of course its gonna be cloudy for the next week hehe.
My First Narrow-band Colour Image
Here is my First ever colour image in Narrow Band using the Hubble Palette (kind of).
I am still learning how to process images taken through narrow band filters, so I probably got a bit carried away 🙂
Eta Carinae nebula: Total exposure time is approximately 1.5 hours with 6 x 5 minute exposures for each narrow band filter: Ha, Sii, and Oiii Filters.
Hydrogen-Alpha Filter vs Red Filter for Astro Imaging
Hydrogen Alpha Filters
To add to my equipment list (as you do), I decided to get a more sensitive Monochrome camera and a set of Narrowband Filters.
When I first entered this hobby I used one shot colour cameras in the past. Either an Canon 40D or the QHY8 cooled camera.
Mono cameras don’t do colour, as you can see from the images below. But this give a few advantages, such as being more sensitive and give sharper pictures (due to the fact that in colour cameras there are pixels next to each other for each RGB colour, so you get slightly reduced resolution per colour and the camera interpolates the pixels in between).
You still can create colour images with a monochrome camera, but you need to take individual pictures through different coloured filters and merge them, post processing to make the coloured image.
This does mean though that your are not limited to Red, Green, and Blue, light like a colour camera. You can use all sorts of specialised filters to pick very specific bandwidths of light.
What amazed me about using a narrowband Ha (hydrogen Alpha) filter, is that even though the Hydrogen Alpha filter captures a much narrower portion of the red band (hence the name: narrow-band), for the same amount of time it revealed much more nebula data depending on the target you are imaging.
The chart below shows the typical narrowband filters that are used for astrophotography. As you can see they only allow light in from very specific narrow areas of the spectrum. If you have ever seen pictures taken by the Hubble telescope, you have probably seen narrowband images. They often reveal more detail by showing light from specific wavelengths emitted by Hydrogen, Sodium and Oxygen. Colour pictures taken with these filters are often presented in what is called the Hubble Palette.
Below is an image of the Eta Carina nebula taken with a mono camera. There are two variants. Each is a single 5 minute exposure taken on the same night. The first is with a standard Photometric red filter, the second is with an Astrodon 6mm Ha filter. You can toggle between the two images by click on the right arrow on the side of the image.
Although the HA shows less stars, it shows a lot more of the nebula.
