SHO vs BiColour

[Midnight_lightning]

I'm relatively new to narrow band imaging and have just produced my first SHO image using PixInsight and following a LightVortex tutorial step by step.

I have a dilemma but don't know enough to know what to do, all suggestions welcome. 

The dilemma is this, I have 7 filters, L, R, G, B ,Ha, SIII, OIII but only a 5 position filter wheel and it drives me mad swapping filters so I'm thinking of upgrading to a 7 filter wheel but would be expensive. 

I intend to produce this style of NB image with Golds and Blues rather than include green and I'm wondering if I can get this effect using Ha and OIII only rather than SHO?

If so I can manage with a 5 filter wheel by using Ha in place of L - i.e. R,G,B,Ha,OIII.

So I guess the question is, If I want to produce Gold / Blue NB images does SHO or HO give the best result ?

Thanks

Jon

 

 

 

[x6gas]

That's a very nice image.

Why don't you experiment processing your data using just the five filters and see if you like the results?  Plenty of lovely HOO images out there...

I must admit that I had the same issue and got fed up with constantly having to change the filter carousel; I always seemed to have the wrong filters on the rig so in the end I bit the bullet and upgraded to a seven filter wheel and i am really pleased I did...

 

[knobby]

Lovely image, same dilemma here ... I'm trying L Ha R Oiii B with the idea I can try R (synth G) B and Ha Oiii (maybe blend of Ha/ Oiii)

[kirkster501]

You’re going to have to experiment mate. However, ultimately a good reason to ensure always buy a seven position filter wheel.  This is not always possible of course if you have a big chip camera and are using 2” filters.

[Midnight_lightning]

I am experimenting but its complicated by my lack of experience processing both SHO or Bicolour. I found an SHO workflow which worked for this image but when I tried to adapt it to Bicolour on the same image using just the Ha/OIII the results weren't as good. I don't know whether its the data or my processing that is the problem. As I'm writing this I just thought maybe go through Astrobin and see what others are achieving with Bicolour - that should help

 

[Adam J]

4 hours ago, Midnight_lightning said:

I am experimenting but its complicated by my lack of experience processing both SHO or Bicolour. I found an SHO workflow which worked for this image but when I tried to adapt it to Bicolour on the same image using just the Ha/OIII the results weren't as good. I don't know whether its the data or my processing that is the problem. As I'm writing this I just thought maybe go through Astrobin and see what others are achieving with Bicolour - that should help

 

If I only had a 5 position wheel I would do one of three things, 

1) Focus fully on narrow band, Ha, SII, OIII, Lum

That combination would allow me to do three channel SHO images and take mono images of objects such as galaxies. I might then change things over for galaxy season later in the year. 

2) Do something half way, R, G , B, Ha, OIII 

So I can take bi-color narrow band images and I can take RGB images without lum, using all RGB subs stacked in place of lum.

3) Sell the 5-position wheel and get a 7-8 position wheel. 

Thats the hardest one to swallow as it involves admiting that you made an error getting the 5 position wheel in the first place. I almost made the same error and then at the last min realised it was always going to turn into a false economy at some point in the future. 

Adam 

[Tommohawk]

Nice image!

I had the same problem and in the end went for an 8 position wheel. All you have to do is wait until we've had about 99 consecutive cloudy nights and then look on the "For Sale" section! 

[Hallingskies]

I tend to stick with HOO and some RGB to give star colour, as I don’t care so much for the Hubble pallet.  Your 5 position wheel would give you good service then.  If you ever want LRGB you’d just have to create a false luminance from the RGB.  

That said, I have a bigger wheel with an SII filter which I hardly ever use - maybe it’s just me but I never seem to get much SII signal compared to Ha and OIII.

[Adam J]

2 hours ago, Hallingskies said:

I tend to stick with HOO and some RGB to give star colour, as I don’t care so much for the Hubble pallet.  Your 5 position wheel would give you good service then.  If you ever want LRGB you’d just have to create a false luminance from the RGB.  

That said, I have a bigger wheel with an SII filter which I hardly ever use - maybe it’s just me but I never seem to get much SII signal compared to Ha and OIII.

I dont even own one and have not missed it so far. Eventually there will be a target which I want to try SHO on but not right now, I like HOO better, its more natural.

[ramdom]

In my view, the problem is going to be due to the fact that a lot of the NB targets (in my case, half) don't have O3 data at all or it's (sometimes much) lower than S2.  So for those targets, even though bicolour could work, it'd have to be Ha and S2.  But there are enough targets so you certainly can plan it so that you do the  HOO ones first, then do the SHS ones every season/year or so (which is what I do in terms of cameras/scope combinations).  It's going to be very target dependent whether RGBHO works or not for any particular target.

I too use a five position EFW but I've decided to not do RGB imaging and instead do a OSC for my RGB images but I just started that this year. The first two years, I stuck with only doing SHO (and L) images. There are so many NB targets out there that I could probably spend the rest of my life doing only SHO images but again I think switching filters once a year isn't a big deal. 

Another option is to go with LRGBHa as a first pass for targets and then once you've done a few dozen, you can come back to the ones that are most interesting and redo them with SHO if needed.  

--Ram

[kirkster501]

You could image perfectly well R,G,B.Ha,OIII.   You'd beed to bin 1x1 though so could take more time.  You need 1x1 somewhere and traditionally this is done on the Luminance.  I have not tried 1x1 on say Blue and 2x2 on R and G.

BTW - Your Heart Nebula is superb indeed!