Hi res. M1 nebula with 300mm newtonian

[Luis Campos]

Hi guys,

Now that I got a couple Xmas presents in advance (an ASI 120MM camera for planets and autoguiding and a set of tube rings for my 300mm newt) I went crazy and decided to put my big 300mm GSO newtonian on the EQ6 and try a small target in narrowband, M1 nebula was the chosen subject for this test as it has some delicate structures when using a Ha filter, unfurtenately i'm having some issues that I still have to iron out, the stars are a bit elongated not due to bad guiding or tracking error (the graph was flat as a pancake) but due to micro wiggling in R.A. wich Ithink is from the stepper motor itself ressonating with the huge OTA, I notice this when doing Hi res lunar and planetary imaging, a slight and fast back and forth movement in r.a. only, this is not a problem for planetary imaging as the ASI 120MM fast frame rates overcomes this but for deep sky it's a real problem!

The way I'm thinking on improving this is to use a hargreaves strut, this is mainly used on long refractors but I think it will add something to my big newt, ok I know an EQ6 is not supposed to carry a 300mm newt with >20kgs but it's what I have...and I love a good challenge!

So here it is, M1 nebula in Ha using 10 min. subs. with my 300mm newtonian and mono cooled Canon 550D with a Baader 7 nm Ha filter, the image is only callibrated with bias, still have to do the flats, I'm not using darks here as it's not necessary

Here the full frame:

https://www.flickr.c...eposted-public/

Here a crop at 75% resolution:

https://www.flickr.c...eposted-public/

Never mind the bad stars, I think this shows promisse when I address the wiggling problem...wiggle, wiggle, wiggle

Cheers,

[laudropb]

Very nice images. Thanks for posting.

[baggywrinkle]

Good images..

[Luis Campos]

Thank you for the kind words,

Merry Christmas!