M45 first DSO attempt

[jonathancd]

Here is my first ever DSO image so please be gentle.

I only have an alt az mount so had to keep exposure to about 25 secs. They are taken with an equinox 80 on a nexstar SE mount. I stacked six 25 sec subs plus 2 dark frames in deep sky stacker. Background seems grey is that because of the full moon or general light pollution. All tips welcome.

thanks for looking.

Jonathan

(click to enlarge)

[blinky]

Very nice, espeially for a first image! What camera did you use? One thing you could try (If you have photoshop or similer) i to lower the mid point of the image (I think thats correct?). Anyway open the image and select levels (CTRL L) and drag the middle pointer towards the white. This will darken your sky bakground.

[jonathancd]

Hello,

thanks for the tip. I am using a 400D.

Jonathan

[anthony]

Very good start. How long can you go before the stars start to trail?

Anthony

[jonathancd]

I think it depends on the bit of the sky I am shooting in but I expect with the alt az mount I'll be limited to 30-40 secs. I live in North East London so with the horrible light pollution we have here Iexpect much longer and the shots would be very orange.

thanks

Jonathan

[Psychobilly]

Hi Jonathan,

Nice first ever DSO...

If you havent got it already download PixinsightLE and the tutorials on DBE this will help with the vignetting and the LP

Billy...

[LostNSpace]

Hi Jonathan!!!

Congrats on your 1st DSO.......

You should be fine working with 25sec subs, just take more of them.....And when taking darks try and use no less than 3 as a general rule.......

To follow up on what Craig mentioned about darkening the background, in PS and Gimp under levels you have 3 droppers, Black, white and grey....if you click the black dropper and then click on part of your image without any stars then it will darken the background.......

Sometimes it makes the BG too dark and unnatural looking but at least it gets rid of that horrible LP......you can always tweak the shadows/highlights and brightness/contrast to give it a more natural look.......

Your images should improve once the moon has disappeared again, you`ve done a fine job considering the bright moon and the LP where you live.......

Mark

[johnh]

Well Done, m45 is a great target bet you can't wait for m42 in Orion which suits dslr perfectly.

[thing]

Very nice first image. What you can also do in DSS is make sure that the RGB curves (bottom left after you have stacked) are on top of each other by moving the sliders. This gets rid of a lot of the orange muck.

[Tim]

Very nice, well done! Are you shooting in RAW mode? If not, try it, you'll get a hundred times more data to play with!

TJ

Little tip: MartinB's tutorials are great and will really help. For this image in particular you could use the levels tool to bring the black point up to the start of the histogram data, and bring the white point down to the end of the histogram line. Right away you will see an improvement. even in this jpeg, which seems heavily compressed there is the indication of a little nebulosity, if you send me the RAW files if you have them, i'll try and bring that out for you. PM me for mail address. Cheers

[jonathancd]

Thanks for all the tips. Have retouched in photoshop and in DSS and I think it is quite a bit better.

thanks again

Jonathan

(click to enlarge)

[MartinB]

Congratulations on your first image Jonathan. Good focus, round stars and well framed - pretty good for starters!!

[jgs001]

Jonathan, that's a nice M45. I'm using a NexStar SLT Alt Az mount, and I've been able to shoot at 120s on M45, M31 and M33. The duration of sub shortens the higher in the sky, and the closer to north/south. Have a look here for info on max sub lengths in Alt Az. I'd suggest try at various lengths and see what you can get away with. I was trying to image a cluster in Cassie the other night, nice and high and 30 second subs were no problem at all. 60 second subs were borderline and field rotation was causing problems in most of them.