M51 - Attempted longer Subs

[johnb]

Hi

I have done M51 before but never really long subs, so here is an attemt at 8 minute subs and im really pleased with it. Think my guiding is nearly there so now I need to go for 10 minute subs I guess;

Think i need more work on my processing skills but hey its all falling into place

Lights - 13 x 480 Secs

Darks - 6 x 120 Secs

Flats x 8

Total Time - 1 Hour 44 Mins

Thanks for looking

Regards

John B

[Bizibilder]

Very good image. May I suggest - use darks that are the same exposure (and temperature) as your lights, also try and get 20+ of each ie darks and flats. Hope this helps

[JCorley]

Lovely picture, yes I agree, get darks the same time exposure and temperature as the lights. I store my darks in folders according to temperature, after a while you accumulate enough variations to not have to take new ones, or at any rate to use a close fit for a quick preview of how the picture may come out.

can you tell me how long is the overall tube length of the skywatcher scope? Is it the 250PDS you have?

Regards John Corley

[johnb]

Thanks, its the 250 DPS and its 1200mm long

thanks for the pointer on darks

Regards

John B

[rfdesigner]

Yup another one suggesting getting the darks correct.

I've seen some very advanced astronomers able to make use of different length subs and darks, but I wouldn't advise it unless you really know what you're doing.

If you're not sure then just stick to using darks of the same length and at the same temperature as the imaging subs.

I'm looking forward to seeing the results of the image once you take some new darks, it could lift it quite a bit.

Derek

[Bizibilder]

May I just add: Darks are a good use for cloudy nights. Set the camera up with the lens cap on and put it somewhere at the temperature you want (I use the observatory, garage or even the fridge depending on the temperature you want and the time of year!). Take your flats (a timer release is very useful: Canon RS-60E3 Comaptible LCD Timer Shutter Release: Amazon.co.uk: Electronics I think is OK for your camera). And store them on your computer for future use.

My own are every 2 °C from -6 to +14 (until it gets warmer!) for 1, 2, & 5 min subs I usually take 24 of each - thats a lot of darks but I now don't have to worry about them!

PS They will need to be re-done from time to time as the camera sensor will vary in response/hot & cold pixels etc over time.

PPS Like the website!!

[dc509]

nice image

d

[johnb]

thanks to all, really good tips for darks, im pushing for 10 minute subs now so having prepared darks will be a real bonus

Regards

John B