Jump to content

sgl_imaging_challenge_2021_2.thumb.jpg.72789c04780d7659f5b63ea05534a956.jpg

Recommended Posts

Hello Astronomers,

During the week when I was imaging the Helix Nebula, I was exposing it when it was east of the meridian.

So as it hit 15 degrees past the meridian and the meridian flip happened, there was no guide star in the OAG FOV so I had the option to pack up and continue imaging another day or try for another object and hope for a guide star.

As the sculptor galaxy was close to the location I slewed to it (with favour western horizon selected in the CGEM settings) and to my joy when the sculptor galaxy was framed a 1/3rd of the frame to the edge there was a guide star in the OAG... WOO HOO :grin: ... and so a second object imaging continued.

After getting 3 nights worth of ISO400 10 minute RGB subs, I found that after processing the image was very amber at best.. almost sepia... and no matter what I done to it it always looked too green or purple at certain parts... just didn't look right.

When I eventually got a chance, I was going to image some pure blue subs to add to the image to correct for the amber look, but as luck would happen, forecast was for at least a week of clouds and rain... this week was no better BUT I did see a break in clouds the other day with a 3/4 FULL MOON!!!!  :mad:

I couldn't afford to let this opportunity go to waste so I imaged NGC253 through a Halpha filter to cut out the moon glow... remembering that when imaging through Halpha in the 40D there is a lot of data in red (of course) and about 30% as bright in the blue channel.... I thought that I could use that added to blue as well as add some halpha to red and perhaps reveal some nebulosity.

I only managed 8 x 15 minute subs before clouds started coming and 4 out of those were usable... here is the result.

Thanks for reading my babble....

MG

post-43662-0-36325000-1440807260_thumb.j

  • Like 13
Link to post
Share on other sites

I have one of those tubes, but I gave up on imaging with it, without ever trying. I have the f6.3 reducer and the whole setup to image with it, but I thought the stars around the edge were going to be really bad. I did a little bit of imaging with it with my old canon.

your field looks pretty flat. maybe I could do some imaging with it after all with my ccd. at 1280mm

  • Like 1
Link to post
Share on other sites

I have one of those tubes, but I gave up on imaging with it, without ever trying. I have the f6.3 reducer and the whole setup to image with it, but I thought the stars around the edge were going to be really bad. I did a little bit of imaging with it with my old canon.

your field looks pretty flat. maybe I could do some imaging with it after all with my ccd. at 1280mm

My work around any coma at the edges is to simply work with a crop limit of 3000-3200 x 2000-2200 from the 40D 3888x2592. That allows me to crop out any bad stars due to coma and vignetting.

Overall I'm very happy of the quality of subs that I'm getting with my NS8. I can't stress enough that tracking and focus are the most important to quality.

A f6.3 reducer & flattener really does do a good job at fixing field curvature delivering a very flat field, at least for a APS-C size sensor.

Don't give up.... Your OTA is capable of some great close up images of DSOs, especially useful for the smaller objects such as the dumbbell or butterfly nebulae.

Link to post
Share on other sites

Correct me if I'm wrong but I'm quite sure that this galaxy is visible from UK.

Yep, it is visible. Doesn't get particularly high but certainly doable with a good southern horizon.

  • Like 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By MarsG76
      The Witch Head Nebula, aka IC2118 & NGC1909 in the constellation Orion, near the star Rigel.
      This object is very large in the sky, being 3°×1°, so I had to use my smallest telescope to deliver the wide angle and low power needed to image all of the "Witches" profile.
      This is a very difficult object to image using a DSLR, and a dark sky is needed to capture it in it's full glory. I thought that I'd give it a go with my DSLR, and see what I end up with... I'm happy that the end result in my image shows the shape of the "Witch Head" but I think that the overall image will not be winning any awards.
      This image has been exposed through a 80mm refractor @ 500mm FL, using my cooled and full spectrum modded DSLR for a total exposure time of 12 hours and 34 minutes, in a semi-rural, Bortle 5 (maybe 4) sky.
    • By MarsG76
      I managed to bag another object, this time the reflection Nebula M78 in the constellation Orion.
      I was planning to capture natural color subs than add some HAlpha and OIII narrowband data to emphesize the image details and reveal deeper matter, but after processing the OSC/RGB subs, I decided that adding the narrowband data is not necessary.
      This image was taken across two nights (juggling clouds), 6th and 11th February, and I managed to capture 3 hours and 18 minutes worth of useful subs (21x60 sec, 19x120 sec, 18x180 and 17 x 300 second subs).
      The telescope used was a 80mm refractor, at 500mm FL using my full spectrum modded and cooled 40D DSLR.
    • By MarsG76
      Mosaic of the Large Magellanic Cloud One of two (known) companion/satellite galaxies of the Milkyway galaxy, located 160,000LY away and only visible from the southern hemisphere. Due to the angular size of the LMC, this image consists of 4 frames, each exposed in natural color at 500mm focal length through an 80mm refractor. The 4 frame are combined into one image to fit the whole satellite galaxy into the frame. The camera used was my astromodded and active cooled canon 40D. Exposure time was 2 hours and 42 minutes per frame for a total of 11.5 hours for the whole image.
    • By MarsG76
      This is a close up of IC 2944, also known as the Running Chicken Nebula or the λ Centauri Nebula, with the Bok Globules visible in the upper third of the frame. IC2944 is an open cluster with an associated emission nebula found in the constellation Centaurus, near the star λ Centauri. This image was exposed using a Cooled and full spectrum astro modded DSLR through a 8" SCT at it's native 2032mm (f10) focal length. The total exposure time was 8 hours and 25 minutes, through a UV/IR filter to capture natural colour data.
    • By MarsG76
      The view of the deep southern part of the Milkyway around the Southern Cross, Crux, and Centaurus region. This image was taken with a Canon 5D mk4 using a Canon L-series 24-105mm Lens set to f4. Image taken from a mountain, a dark(ish) location, down southern part of NSW near Kiama, called Saddleback Mountain.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.