Not A Great Night Data Wise! NGC1396

[wesdon1]

Hi all. So recently I got my first light with my L-Extreme 7nm/7nm filter. The night didn't go to plan data wise for three main reasons...

One, I totally underestimated the length of sub exposure time ( 90sec )

Two, I didn't get anywhere near the required total exposure time ( 72mins )

Three, I didn't frame my target properly so the "elephants trunk" part of the neb was almost out the frame ( 6-7 o'clock position ) Because I had such limited data, I had to really stretch it to get anything out of it.

I am not pleased with results but conversely I am happy for my mistakes because ultimately they educate me! next time I won't make such mistakes!

( edit - The clouds rolled in after 70-80 minutes!! So not entirely my fault! lol )

*IC1396 aka Elephants Trunk Nebula

*49 x 90sec subs/73.5mins total exposure

*HEQ5 Pro Mount

*66/400 ED doublet Refractor

*L-Extreme Filter

*Canon 600D astro modded DSLR

*ZWO 120MM Guide Camera

*Bortle7/8

*Light processing in PS, stacking and registration in DSS

 

Edited August 18 by wesdon1
missed a bit!

[smashing]

I mean....for just over an hour's worth of data that looks good to me. I used to not really do much with my modded DSLR unless I had upwards of 4-5 hours or so.

 

[ollypenrice]

May I ask how you got the framing wrong? Did you rely on plate solving? We seem to be entering a world in which plate solving is regarded as the beginning and end of framing an image, but it isn't. It may or may not be the beginning, but it certainly isn't the end. I would always check it very carefully before pressing Go.

Olly

[smashing]

41 minutes ago, ollypenrice said:

May I ask how you got the framing wrong? Did you rely on plate solving? We seem to be entering a world in which plate solving is regarded as the beginning and end of framing an image, but it isn't. It may or may not be the beginning, but it certainly isn't the end. I would always check it very carefully before pressing Go.

Olly

I have also fallen into this trap recently, I now use it to get myself roughly in the right area and then get the framing that I want and then save that as the target for future nights.

I actually tried this target out the other night and the Asiair takes you to it no problem but it certainly wasn't optimal.

 

[Elp]

It's not bad, I assume with framing you want the trunk more centred but at least you've captured it. If you can try for 2-3 minutes exposure. Or stick to around 60s, but you need around 3-4 hours with the 600d to see more "significance", with that camera at around 5-6 hours the noise starts to reduce significantly also.

[wesdon1]

On 18/08/2024 at 18:55, ollypenrice said:

May I ask how you got the framing wrong? Did you rely on plate solving? We seem to be entering a world in which plate solving is regarded as the beginning and end of framing an image, but it isn't. It may or may not be the beginning, but it certainly isn't the end. I would always check it very carefully before pressing Go.

Olly

I wanted the "trunk" part more centred. No I actually own an ASI Air but I haven't been able to use it properly yet because it starts to overheat when controlling my 600D DSLR? I called RVO who sold me it and they said send it back to them so they can run tests to check if it's the ASI Air with the issue or my camera. But to properly answer your question, I simply use GOTO on the Synscan, then manually frame up my targets with Synscan controller. on this occasion I forgot to frame up the target to my liking! I agree a lot of people are now using plate solving religiously! 

Regards, Wes. 

 

[wesdon1]

On 18/08/2024 at 20:43, Elp said:

It's not bad, I assume with framing you want the trunk more centred but at least you've captured it. If you can try for 2-3 minutes exposure. Or stick to around 60s, but you need around 3-4 hours with the 600d to see more "significance", with that camera at around 5-6 hours the noise starts to reduce significantly also.

Thanks for kind comment!

Yes I don't know where my head was at thinking 90sec subs were ok with a 7nm/7nm filter?? I think your suggestion of 2-3 min subs would be much better. 

Oh right? You know I've been wondering for a while, how my data would be if I managed to get 5= hours on a neb with my 600D, so thank you for the advice, that's really helped me a lot! I'll aim for as many hours as weather allows ( 50/50 I might get some cloud beaks tonight! ) and then when it comes to post processing I'll have useful data to play with!

[phantom199]

The clouds can be a pain, but at least you got some data to work with.

[Albir phil]

20 hours ago, wesdon1 said:

I wanted the "trunk" part more centred. No I actually own an ASI Air but I haven't been able to use it properly yet because it starts to overheat when controlling my 600D DSLR? I called RVO who sold me it and they said send it back to them so they can run tests to check if it's the ASI Air with the issue or my camera. But to properly answer your question, I simply use GOTO on the Synscan, then manually frame up my targets with Synscan controller. on this occasion I forgot to frame up the target to my liking! I agree a lot of people are now using plate solving religiously! 

Regards, Wes. 

 

Hi like you I don't use platesolve I found that I polar align with polemaster, then do a 2 star align with synscan this gets the target almost centre in f o v🫡