Elephants trunk nebula versus na nebula

[TiffsAndAstro]

So I really like my image of the north America nebula ngc7000.

So I decided to try the elephant trunk nebula because it was just about visible at 1130 and could do three hours on it (got about 55 x 120 sec subs in the end). It would be even betterer

After a quick stack and 2 hours processing nelly, it's crap. I will do this with more care and attention again hopefully tonight and maybe it will turn out better but I'm not confident it will be anywhere as nice as my ngc7000.

Is there some major reason why ngc7000 seemed easier than elephant trunk? They're both Ha emission and vaguely position in the sky. No moon for either too.

If so, what is that difference? So I can use it to choose more realistic targets than might turn out more like ngc7000 for my gear and bortle 6 etc.

 

[carastro]

Could be less bright than NA neb, not sure as l had a modified DSLR when l tried it before l got a Cooled CCD camera.  
 

Did you by any chance miss the target?  
 

 

[TiffsAndAstro]

28 minutes ago, carastro said:

Could be less bright than NA neb, not sure as l had a modified DSLR when l tried it before l got a Cooled CCD camera.  
 

Did you by any chance miss the target?  
 

 

tbh that was my only thought, but telescopius doesn't list its apparant brightness.  random google result say magnitude of 3.5 and na nebula apparent visual magnitude of 6 which makes nelly quite a lot brighter than na?

fortunately, i put aside part of my initial budget to pay for a premium flog which i am currently applying vigorously to the data  also ill try binning again forgot that

Edited June 5 by TiffsAndAstro

[TiffsAndAstro]

there is definately something out there i think. here is a quick screenshot of histogram after gradient removal, noise reduction, photometric colour calibraion  and then binning 2x2.

that garnet star is bright. also my dust mote is still in the same place and its annoying me. i did take flats again so im not sure what's causing it.

 

Edited June 5 by TiffsAndAstro

[carastro]

Yup that’s part of the Elephant trunk. 
Are you referring to that black dot at the top? 

Edited June 6 by carastro

[TiffsAndAstro]

2 minutes ago, carastro said:

Yup that’s part of the Elephant trunk. 
Are you referring to that black dor at the top? 

yeah same dot was in my ngc7000 image, i assumed new flats would remove it. i can touch it up a little in gimp, just can't think how its still there.

im gonna restack the lot manually see if the couple of frames i chose not to stack might make a difference.

 

[carastro]

I have one like that on one of my cameras l think it is on the sensor but because l use a dual set up and sometimes multi nights there is overlap.

Don’t suppose you dither as that might help if you do a large dither. 

[TiffsAndAstro]

18 minutes ago, carastro said:

I have one like that on one of my cameras l think it is on the sensor but because l use a dual set up and sometimes multi nights there is overlap.

Don’t suppose you dither as that might help if you do a large dither. 

i assume flats help with dust on sensor too but im not certain. i haven't removed my camera from the scope for at least a month, so no harm me having a look and running the clean sensor thing

i dither by 7 pixels which i got from a dithering calculator. i think this is 7 pixels on the guide cam but again not certain  i also drizzle and seemingly have to resample 50% before using starnet or blue screen of death (over 260 tiles seems to do this bluescreen) but binning 2x2 has a similar/same result to resampling so i just do that now. 

[TiffsAndAstro]

also any recommendations for a different target when there's the next clear sky in a couple of decades's time?

definitely not tonight

not good by any stretch of the imagination (geddit?) but its better than nothing. ill give it another go but at least there is something visible

 

Edited June 5 by TiffsAndAstro

[woldsman]

2 hours ago, TiffsAndAstro said:

also any recommendations for a different target when there's the next clear sky in a couple of decades's time?

definitely not tonight

not good by any stretch of the imagination (geddit?) but its better than nothing. ill give it another go but at least there is something visible

 

Both images make good use of your gear. You are just limited by not having a narrowband filter as this reduces contrast on an emission nebula. 

[TiffsAndAstro]

31 minutes ago, woldsman said:

Both images make good use of your gear. You are just limited by not having a narrowband filter as this reduces contrast on an emission nebula. 

Au natural is the new black i read somewhere  i quite like my broadband ngc7000, hence why i was expecting what seems to be a vaguely similar target, elephant trunk to give me vaguely similar results

also im reluctant to get any filters until i get a proper camera, though its possible, if im ever able to visit my (very) local astro club and join i could loan one.

also, guess who forgot that there were some clouds last night. i think i had nightmares about phd2 bonging away. while i checked the plot in siril and rejected the high fwhm subs, i didn't notice bands of cloud in the ones with lower fwhm. gonna remove them and try again.

Edited June 5 by TiffsAndAstro

[Elp]

48 minutes ago, TiffsAndAstro said:

im reluctant to get any filters until i get a proper camera, though its possible

I wouldn't hesitate other than available funds, you can always use the filter with an OSC camera after anyway, it'll separate ha/o3 signal from the background sky literally like magic, you won't believe the difference. The only thing I don't like about them, sometimes if they catch stray light they can play havoc on your gradient removals, and they don't give true RGB colour starfields, but that's easily remedied with one or two hours imaging via a luminence filter.

Regarding elephant trunk, it is actually quite dim compared to what you'd expect. I did it in SHO and the colour saturation doesn't pop compared to say the rosette (IE the pixels were far more saturated in the latter target, I'm not talking about PP colour adjustment).

Edited June 5 by Elp

[TiffsAndAstro]

1 hour ago, Elp said:

I wouldn't hesitate other than available funds, you can always use the filter with an OSC camera after anyway, it'll separate ha/o3 signal from the background sky literally like magic, you won't believe the difference. The only thing I don't like about them, sometimes if they catch stray light they can play havoc on your gradient removals, and they don't give true RGB colour starfields, but that's easily remedied with one or two hours imaging via a luminence filter.

Regarding elephant trunk, it is actually quite dim compared to what you'd expect. I did it in SHO and the colour saturation doesn't pop compared to say the rosette (IE the pixels were far more saturated in the latter target, I'm not talking about PP colour adjustment).

i realise some/most of this, but main problem is my 'filter holder' is inside the nose peice of the flattener...and i don't use the nose piece. i could get a clip in for my dslr but they're expensive and won't work with a proper astro camera. also i haven't bothered looking at mounted/unmounted and i can't fit a filter drawer between focus tube and flattener otherwise i could use a rotator

also not even glanced at any narrowband siril videos. 

pp colour adjustment is photometric colour calibration? im siril + (a slight bit of) gimp only. however, if its pop you want shade you eyes and glory at the clown show below

12 hours ago i thought i had nothing. now i have something, whatever that something is  still needs a little work

 

 

 

[Elp]

6 hours ago, TiffsAndAstro said:

but main problem is my 'filter holder' is inside the nose peice of the flattener...and i don't use the nose piece

Any reason why? All flatteners I've used have a 2 inch front end (obviously to fit a 2 inch aperture focuser, I've used around four different ones) and I've always screwed in the filter there if I'm not using a filter drawer which you can't use due to using a DSLR.

2 inch is also a useful size if you use camera lenses as a lot of the time with them I'll screw on the filter out front, sometimes I used step down rings to do this.

Elephant Trunk actually frames better with a camera lens too.

Edited June 6 by Elp

[900SL]

I think you are ready to move to a dedicated astro camera. The difference is amazing. I shot this with a 533MC pro and dual narrowband filter, Redcat 51

 

Edited June 6 by 900SL

[Elp]

1 hour ago, 900SL said:

I think you are ready to move to a dedicated astro camera. The difference is amazing. I shot this with a 533MC pro and dual narrowband filter, Redcat 51

 

It's a nice image for sure, but you have to attribute a lot of the separation from the background sky due to the filter. Even with my D2 filter the difference from imaging plain luminence is night and day, with my lextreme even more so, and that is with an unmodded camera. The astro camera will help more, and also have less noise, but it doesn't mean an astro camera is a necessity, many people do excellent images with camera bodies, modded or not.

There is no substitute for total imaging time which the OP needs to really start concentrating on doing, I was the same at the beginning trying to image anything and everything, in fact I still do it testing the feasibility of certain targets, once settled on something quality NEEDS more imaging time.

Edited June 6 by Elp

[TiffsAndAstro]

1 hour ago, 900SL said:

I think you are ready to move to a dedicated astro camera. The difference is amazing. I shot this with a 533MC pro and dual narrowband filter, Redcat 51

 

holy smoly that's lovely. its broadband right? and i agree i need an astro cam but need the funds first.

also looking into them a bit more im not sure a imx585 based one is as ideal for me as i thought. so im thinking zwo533 (i think it is) with the square sensor, but i don't like the aspect ratio. looks like 1980s television.

having said that, i've only just noticed your amazing image is square, so maybe it doesn't really matter to me after all.

Edited June 6 by TiffsAndAstro

[TiffsAndAstro]

32 minutes ago, Elp said:

It's a nice image for sure, but you have to attribute a lot of the separation from the background sky due to the filter. Even with my D2 filter the difference from imaging plain luminence is night and day, with my lextreme even more so, and that is with an unmodded camera. The astro camera will help more, and also have less noise, but it doesn't mean an astro camera is a necessity, many people do excellent images with camera bodies, modded or not.

There is no substitute for total imaging time which the OP needs to really start concentrating on doing, I was the same at the beginning trying to image anything and everything, in fact I still do it testing the feasibility of certain targets, once settled on something quality NEEDS more imaging time.

im certain you're right about imaging time, but when i took this, there is no astro dark and the 'next type of dark' is about 1130 to 230 and the number of stars in my subs according to nina was about 550 at 2pm and by 215 it was 18 stars

i did save my sequence, so i can resume as soon as there is a clear sky, but doing it 2 hours per night is not great  

to be fair, it was more of a test of "can i even get anything" (like my ngc7000) and it seems i can, just about. but need a lot more time especially with no astro dark.

[Elp]

Imaging during summer isn't great (it's great in that you don't have to wear three or four layers of clothes and a coat), using a dual narrowband filter on emission gives you around 15-30 mins or so each side of darkness extra imaging time.

[TiffsAndAstro]

9 minutes ago, Elp said:

Imaging during summer isn't great (it's great in that you don't have to wear three or four layers of clothes and a coat), using a dual narrowband filter on emission gives you around 15-30 mins or so each side of darkness extra imaging time.

yeah i don't like the cold   but at the moment i can have everything outside and plugged in ready to 3ppa in 8 minutes after the sequence is going i can sit inside and maybe even risk sleeping for a few hours.

[900SL]

1 hour ago, Elp said:

It's a nice image for sure, but you have to attribute a lot of the separation from the background sky due to the filter. Even with my D2 filter the difference from imaging plain luminence is night and day, with my lextreme even more so, and that is with an unmodded camera. The astro camera will help more, and also have less noise, but it doesn't mean an astro camera is a necessity, many people do excellent images with camera bodies, modded or not.

There is no substitute for total imaging time which the OP needs to really start concentrating on doing, I was the same at the beginning trying to image anything and everything, in fact I still do it testing the feasibility of certain targets, once settled on something quality NEEDS more imaging time.

I think shooting dual narrowband with a unmodded camera is like going to watch Dune wearing blinkers, in some ways. Depends on how much Ha the sensor can pick up, and then you have the noise due to the significantly longer exposures.

Agree on imaging time though. Mr Tiff seems to have the bug however, so he will be shooting all and sundry like an overexcited flea and posting same here, so the sooner he makes the move to a dedicated camera the better he will find it. And if bortle 7 or higher I'd likely go 533MM (mono). Save the expense and headache of nickel and diming your way to that point by intermediate steps, and not being happy with the results.

 

 

 

 

[Vroobel]

I also think that the dual-narrowband filter is the must have. Here is one of my best pics taken with modified Canon 6D and L-eXtreme filter:

https://www.astrobin.com/d2jqql/

 

 

[TiffsAndAstro]

2 minutes ago, 900SL said:

I think shooting dual narrowband with a unmodded camera is like going to watch Dune wearing blinkers, in some ways. Depends on how much Ha the sensor can pick up, and then you have the noise due to the significantly longer exposures.

Agree on imaging time though. Mr Tiff seems to have the bug however, so he will be shooting all and sundry like an overexcited flea and posting same here, so the sooner he makes the move to a dedicated camera the better he will find it. And if bortle 7 or higher I'd likely go 533MM (mono). Save the expense and headache of nickel and diming your way to that point by intermediate steps, and not being happy with the results.

 

 

 

 

i really really don't have the money for a mono + filters set up though so i think a osc and filter + drawer is a reasonable compromise. well, more of a hope i guess.

but even that is out of my reach for a while.

[Vroobel]

So start with an affordable (but decent) dual-narrowband filter ASAP, then try to modify your DSLR when you can. I agree that the astro OSC cam is better than the modded DSLR, but as you can see the DSLR can also satisfy you. 

Some cheap dual-narrowband filters may bring halos around stars, but it's up to you if you accept them or not. 

[900SL]

48 minutes ago, Vroobel said:

I also think that the dual-narrowband filter is the must have. Here is one of my best pics taken with modified Canon 6D and L-eXtreme filter:

https://www.astrobin.com/d2jqql/

 

 

Thats a great example of what can be done.   I see from Astrobin that's around 5 hrs at 600s exposures. How do you deal with thermal noise with the DSLR? Darks etc?