Problems with Iris nebula RGB channel combination

[Wyvernp]

Morning All,

I'm having an issue combining my channels in pixinsight. I have 3 separate R, G and B channels made from 17x30sec and 7x300sec subs each.

When I combine them the channels histograms seem to match so closely the entire image still looks greyscale. I'll upload them shortly in case anyone wants to have a look.

Thanks in advance.

Wyvern

[Wyvernp]

Blue_HDR.fit

Green_HDR.fit

Red_HDR.fit

[Astrosharkey]

Just had a very quick go with PS and Fits Liberator and cannot get any colour to come through on the combined image, will have another look later with more time.

[michael.h.f.wilkinson]

I had a go in GIMP and got some colour (the red has a satellite trail by the look of it). As even, colours are subtle, and boosting saturation gets more pronounced. I will also give APP a go

[michael.h.f.wilkinson]

This is what I get in APP followed by boost in saturation in GIMP. There is some subtle colour there, along with more trails

[Wyvernp]

12 minutes ago, michael.h.f.wilkinson said:

I had a go in GIMP and got some colour (the red has a satellite trail by the look of it). As even, colours are subtle, and boosting saturation gets more pronounced. I will also give APP a go

 

14 minutes ago, Astrosharkey said:

Just had a very quick go with PS and Fits Liberator and cannot get any colour to come through on the combined image, will have another look later with more time.

Glad to see it's not just me, thanks for trying. Unfortunately yes there's a couple of satellites at the moment, I don't yet have enough subs to do any sigma clipping.

[wornish]

You have multiple satelite trails in the Red and also two in the Green.  These don't help when it comes to increasing the colour saturation in the Nebula.

[Wyvernp]

Yeah, I think I'll try again after I collect a few more subs tonight.

[Fieldsy]

I'm having a few issues with this target myself data ql not being that good, apparently it's not a easy target.

[wornish]

I think you are right. Getting the detail at the core of the nebula itself at the same time as getting the dust clouds to stand out is a real processing challenge.  There are quite a few YouTube videos of people trying different techniques.  

[Wyvernp]

I think last nights data just made things worse... they are at 45 degree rotation to the ones from the previous night. Still the satellite trails are gone but the image still looks colourless

[wornish]

If you can you share your new stack for each channel I will have a go using APP to see if I can get more colour out.  

[Wyvernp]

Blue_HDR.fit Green_HDR.fit Lum_HDR.fit Red_HDR.fit

 

Here, It's not great data because of the rotation. Looks like i'm going to have to image for a few more nights  

Edited May 27, 2020 by Wyvernp

[wornish]

No success,  I can squeeze a bit of colour out of the nebula but nothing from the stars themselves.

 

I think you are right in saying more data needed.

Edited May 27, 2020 by wornish

[Wyvernp]

Yeah and at only 3 hours max of data each night this time of year it might take a while

Thanks for trying though!

[Wyvernp]

Whilst I gather more data over the next few days, Can anyone think of any reason why there's such a lack of colour? I understand that if the histograms have almost identical curves this would happen as there will be equal amounts of R, G and B light, making white. But I'm a little concerned about my setup.

[Wyvernp]

Ok, I figured it out. I removed the camera from the filter wheel and tried to rotate through the filters in SGP. Well... it doesn't move so all exposures were from 1 filter...facepalm

[MarkAR]

Does the filter motor run do you hear nothing ?

If it runs it might just be out of alignment and not engaging the wheel.

[Wyvernp]

Just now, MarkAR said:

Does the filter motor run do you hear nothing ?

If it runs it might just be out of alignment and not engaging the wheel.

So when I power up the rig the motor rotates through the filters so mechanically it is functional. The filters are aligned but theres something wrong with the communication between SGP and the wheel. Trouble shooting now.

[MarkAR]

Good, that's ruled out mechanical issues. Try a different cable ?

[Wyvernp]

Just sorted it, it was using the wrong ascom driver... totally my bad I had loaded the usb one when I needed to be using the one for a direct link with the camera. Thanks all for your help and apologies for wasting your time.. On the plus side I now have all the luminence subs I'll ever need!

[MarkAR]

Glad you sorted it out, now to get loads of colour data to match the piles of luminance.

[happy-kat]

Might have a fiddle later that night make a nice grey tone image

[wornish]

I actually thought yesterday that they were all too similar but held off saying it.  The colour I managed to force out was simply the very slight difference between the three sessions.

Glad you have found the solution.  

Edited May 28, 2020 by wornish

[Wyvernp]

Well I managed to get some data last night, it definitely needs more...and a bit more love in processing but a huge improvement in terms of colour.