M13 from tonight

[Anweniel]

Heres my first ever glob attempt, M13 from this evening, unfortunately sat right behind the sodium street lamp so massive gradient that I cant seem to remedy:(

Anyhow heres a crop about 20mins in total of lights:

lights: 41 x 30s @ ISO 800

Darks: 21 x 30s

Flats: 25

Bias: 40

[malc-c]

Nice - shame about the street light. Here's one of my raw subs - 300 seconds @ 800 ISO - just cropped to fit forum specs

[Anweniel]

Thats very nice Malc-c I assume those hot pixels are from the longer exposures? Wish I could tease out 300s subs but I think the exposures I get from the alt-az are not too shabby at times. Was getting some decent 60s out of this last night but I wanted to keep as many as possible considering the position of the street lamp so stuck with 30s I leave about the same period of time between taking exposures and @ ISO 800 havent had any hot pixel problems - touch wood.

You put me to shame though your single sub is better than my stack by a country mile lol

[malc-c]

Yes, the camera was giving a fair few hot pixels last night, which hopefully the darks will take care off when processed. If your shot was on an alt-az mount then that is very good going to get it that precision. I cheated, mine was guided

[Anweniel]

Hardly cheating Malcolm, I would certainly be guiding and using equatorial if I could! Its still a massive learning curve for me and I have wanted to image a cluster for a while and I suspect when I do get a CGEM I will need to learn to look for such things so its good to talk to experienced guys like yourself, best way to learn

I think my flats are poor maybe they would help with the light reflecting from the lamp but I doubt it would sort it out completely, even with 25 the colour version is decidedly red over half the mage from one corner to the other

[malc-c]

What camera did you use. I have a cls filter fitted in my canon 400d. it does seem to reduce the colour in the images I take, but removed the LP very well

[todd8137]

Hi the image is great lp spoils lots of great pics but ou got righ in to the core lovely image

[Anweniel]

Yeah I missed a lot of info out didnt I! heres the kit:

Telescope: William Optics MEgrez 90

Mount: Skywatcher Supartak

Camera: Canon 1000D ( unmodded)

Filter: Skywatcher LP

The LP filter does a decent job it was just the fact that it was almost right down the throat of tube last night :/

[Anweniel]

Thankyou Todd

[Anweniel]

Had a mess with a colour crop, not sure its any better tbh but a little larger if nothing else lol

[Gina]

Was that with LP filter? Very annoying, that street light!!

[Quatermass]

Great shot shame about the LP problem might be worth taking a trip out to a dark site for this one to get more detail but great to be able to get out there and have go at last.

[Anweniel]

Was that with LP filter? Very annoying, that street light!!

Yes Gina the skywatcher one, sorry I was late posting the equipment details. It performs quite well for the price but it wasnt much better than someone shining a big orange torch right down the scope lol.

Thanks again Mark, yes its great to have gotten out, 2 nights in a row!!! Clouds have made an unwelcome return here today and the forecast is for a return to the bad weather - sigh

[Gina]

Ah yes. I've got the Astronomik CLS-CCD clip-in filter and that seems to work very well with street lights.

[Anweniel]

They do look like a fine tool, they are a little expensive and I feel the 'real' solution is to move away from the LP, at ~£27 the SW LP filter is value for money. I think when I invest in my own DSLR (using my gf's atm) I will look to mod it and probably go for the Astronomik filter