M1- crab nebula

[gonzostar]

This image taken of M1 was taken over a few rare clear nights. Thought i would process this while awaiting another un. I have cropped this one to see some detail

Telescope - 102mm APO ES refractor on a AVX mount

Camera- Canon 450d unmoded iso800 with a Astronomik CLS filter.

Duration 5.5 hours   - 300s lights also with Flats, bias, and darks. Processed in PS

Thanks for looking!   Any ideas to bring out improvement more  much appreciated

Dean

[wimvb]

That looks great. The only constructive criticism I could have is that personally, I would darken the background a little. This will make the nebula "pop" a little more.

[gonzostar]

Cheers Wim, Will make the nebula pop out later  

Next plan is going to be the Orion Nebula not sre how to shoot this oject with my set up

Either, lots of short subs say 60s 

or 300s subs

or a combination of both?  to get the trapezium and the outer dust parts. 

Just waiting for a clear night! 

Dean

[old_eyes]

You need both long and short exposures for Orion Nebula and then combine using a high dynamic range method. I used the version in PixInsight to create this image.

 

good luck!

 

[gonzostar]

Thanks for the link lots of useful informaton.  So for example 40 * 1min subs, processed to get a image

Then 60 * 5min subs processed to get a image.

Blend the 2 images in PS would that work? 

 

Dean 

[wimvb]

There is a workflow in ps that can do this. Jerry Lodriguss wrote tutorials about this

http://www.astropix.com/html/j_digit/toc_dig.html

[old_eyes]

11 hours ago, gonzostar said:

Thanks for the link lots of useful informaton.  So for example 40 * 1min subs, processed to get a image

Then 60 * 5min subs processed to get a image.

Blend the 2 images in PS would that work? 

 

Dean 

You need some really short subs for this target. The trapezium and core are surprisingly bright. 1 min subs are likely too long, and since you can collect short subs quickly it does not cost much time to have them available in the mix

[gonzostar]

1 hour ago, old_eyes said:

You need some really short subs for this target. The trapezium and core are surprisingly bright. 1 min subs are likely too long, and since you can collect short subs quickly it does not cost much time to have them available in the mix

Cool Will drop it down to 30s. I have backyard EOS so this should make tjings easier  

[gonzostar]

10 hours ago, wimvb said:

There is a workflow in ps that can do this. Jerry Lodriguss wrote tutorials about this

http://www.astropix.com/html/j_digit/toc_dig.html

Thanks for the link. Looks like lots of practice and scratching my head!  But will be good fun though.  

[gonzostar]

Does the total time need to match for the short and long sub frames?

eg 2 hours worth of 30s subs for the core

     2 hours worth of 300s subs for the outer nebula?

If that makes sense or not

Dean

 

[old_eyes]

Now you are stretching my knowledge, and others may answer better, but the way I look at it, it is the number of subs that counts rather than total time. So when I did mine I used the same number of subs at each exposure. Obviously, more time means better signal to noise because more subs, but at shorter exposures you are dealing with brighter and better signal to noise parts of the target, so don't need to spend so much time to collect a useful signal.

Just a comment, you may want shorter exposures as well. My shortest was 2 sec at ISO 800. That contained useful information on the bright stars and the trapezium. Longest were 120 sec. More data always better (cf Olly Penrice's mega project 

), but us ordinary mortals can do useful things in a single night with average seeing and a typical UK sky.

[gonzostar]

 

Thanks for useful tips much appreciated

400 hrs of data that would take a10's  of years with my set up!  

I have attached a single 30s raw file from last night is this to bright?. I am concerned if i go to low with exposure i may not get enough stars for DSS, Especially in my LP skies. So i do tend now to go more data

Cheers

Dean

 

LIGHT_30s_800iso_+12c_20171118-00h53m25s777ms.Info.txt

[Stub Mandrel]

21 hours ago, gonzostar said:

Does the total time need to match for the short and long sub frames?

eg 2 hours worth of 30s subs for the core

     2 hours worth of 300s subs for the outer nebula?

If that makes sense or not

Dean

 

No similar numbers of subs, in fact the short ones will be less noisy and you will not be stretching them hard so you will not need as many

[gonzostar]

Cheers that makes sense, How short where your short subs?

[Stub Mandrel]

58 minutes ago, gonzostar said:

Cheers that makes sense, How short where your short subs?

Looks like I took 101 subs at 5 seconds and 97 at 30 seconds, so clearly not taking my own advice.

Here's the (Massively overprocessed!) result. I'm going to try stacking these subs with my five minute ones.

[gonzostar]

Cool image, Are you at a dark site for 5 sec? The Trap is showing up really well  

[Stub Mandrel]

13 minutes ago, gonzostar said:

Cool image, Are you at a dark site for 5 sec? The Trap is showing up really well  

No, just in my garden.

[gonzostar]

Same here processed int back garden.  I have attached a very crude image processed last night and by all means not a finished product. This is just 23 mins worth of 30s subs, a heck of a lot more data needed but as a start can you see the Trapesium or do i need to decrease time for sub frames to get it more? 

Cheers 

Dean