Advise for Heart and Soul Nebula

[LordLoki]

So i would like to snap a Picture of the Heart Nebula and also of the Soul Nebula

Beginning of the Year i got myself a Zwo Asi 1600 Mono and a filterwheel before i was shooting with my Canon 60D

So far i only had 1 productive night out with the new Cam, due to work and stuff and also a lot of sheit weather

Now for the next clear night i would like to shoot the Heart Nebula and try out the new Narrowband Filters. And i was hoping you fine folks could give me some tips on what to use.

I have LRGB Filters and Ha,S2,O3 at my disposal and shoot through the explore Scientific ED80 currently no field flattener but a 0.8 reducer/flattener should be arriving hopefully before end of the year.

First question would be what settings to use for Binning gain (bortle 4 if that matters)

and then i got the info that Narroband is good for these targets and if i shoot only one night expose HA/S2/O3 equally if i go for multiple nights do more S2/O3 

Would anyone be able to confirm that and maybe give some info from experience what ratio would be good?

Thanks in advance   

and if anyone is interested my first try with the Zwo and LRGB Combination feel free to leave feeback as well

First results with new Zwo only L Channel

First attempt with Zwo camera and first try to combine all channels

Edited December 10, 2020 by LordLoki

[Adreneline]

This was my take on the Heart in SHO:

This was taken under Bortle 5 skies and so there is no LRGB content; when I've attempted LR~GB it has always been disappointing to me.

All are taken with gain 139, offset 50 and temperature of -20 with no binning.

Nearly everything benefits from more data

HTH

Adrian

 

[LordLoki]

Great Picture if i get somewhere even close to that id be a very happy man

Thanks for the tips and just to clarify that i understand binning correctly no binning would mean 1x1 in APT correct?

[Adreneline]

1 minute ago, LordLoki said:

no binning would mean 1x1 in APT correct?

I don't use APT but yes - 1x1 implies no binning.

There are numerous threads on SGL re. the benefit or otherwise of binning and whether you should hardware bin or software bin.

I have used software binning in PixInsight to convert OIII 1x1 binned to 2x2 binned with, in my view, little benefit - but! - that could have been a function of the original poor data. If I have read the threads on here correctly I believe there is a concensus that software binning is preferabe - but don't quote me on that!

There are also extensive threads on using different gain/offset with the 1600 on SGL and CN. In the end I decided to go with the 'keep it simple' approach and always use the same gain and offset - makes life easier with calibration frames. I am sure it might be fun to experiment with different settings but we get so few clear nights I can't afford to lose them to experimentation.

Good luck.

Adrian

 

[rickwayne]

Adrian gives good advice, but I would modify it slightly since you're looking at narrowband. ZWO actually did some experimenting and their results indicated that if you want to maximize dynamic range (i.e. get dim stuff but not blow out stars), use the lowest gain. If you want to minimize read noise and shorten exposure times, use the gain where read noise is low but you still have some kind of dynamic range left.

For me, that means 65 on my ASI183MM for LRGB, because star color is a thing. For narrowband, 178, which is the max practical gain on that camera (or so I read from the greybeards) and I'm not getting real star colors in the first place. Likewise for temperature, there is no significant improvement by cooling past the knee of the curve and so it's best to pick one reasonable temperature and always use that unless environmental conditions absolutely prevent it. For the weather in Wisconsin that's -10C.

Likewise exposure, you can drive yourself nuts looking for the perfect exposure but again the gains are really marginal once you've got the peak of the histogram clear of the left edge and aren't blowing out stars. Piling on the sub-exposures for more integration time is a much more flexible and sustainable strategy. You can always go out and shoot more!

Since narrowband filters aren't passing nearly as much light, you'll likely wind up with better results if your standard narrowband exposure time is as long as you can get without mount problems. I'm using ten minutes now, but have gone as short as 30 seconds (!!) when my autoguiding was cranky.

Finally, for a first outing, consider simplifying your life and just capturing and processing Ha. It's by far the dominant signal in that target, and IMO a monochrome image of the Heart is not bad at all. The Soul is less interesting graphically and perhaps cries a little more for color.

[LordLoki]

@rickwayne thanks for the tips, will look into the topic! 

So far i have only done unguided shots but the tracking on the EQ6-R is good and i use a Polemaster for polar alignment so i usually can get away with a couple of minutes of exposure. 

I like the idea of starting with HA only for the first try less points of failure due to filter changes :D 

Also nice shots of both targets! and you are right the Heart is still sexy in mono :)

 

[rickwayne]

Not nearly as sexy as the Horsehead though >;-}