Gina

No, that doesn't work.

Just been reading about multiplying the Ha and OIII to produce a synthetic green instead of adding proportions of each. This was using Photoshop but the same thing should be "do-able" in PI I think.

Running the simulator I reckon if I got some clear night sky before too long I could capture two or three hours of SII for the Heart and Soul with the 135mm lens. I could also do with more OIII. Previous subs were captured with a gain of 440 but I could increase this to 500 or 600 and capture more data in a given time. I think probably I'd best go for SII first as that's the worst set of data.

Been play around with different formulae in PixelMath but the only combination that seems to give any colour is HSO. I guess the problem is that there's very little nebulosity showing in the SII. Maybe I should stick to bi-colour until I can get more SII data.

Tweaked the green curve.

Bit too much black level on that one - here's another. But trick to get the balance right but practice makes perfect they say Hmmm... bit green this one - tried SCNR and it turned purple!! (magenta)

Another go with curves on the bi-colour.

Had another go with curves on the tri-colour but I think I've still cropped the black a bit. Better but I'll probably another go. Here's a full res version saved in PNG format.

Thank you The O could have done with more data - yes it's a lot weaker than the H. I'm still learning the best techniques with this combination of lenses and camera. I think this season will probably be put down as learning and maybe next year I'll have a lot more experience and know more what to concentrate on. Still hoping I can make some reasonable final images from the data I already have though.

Thanks It was a very quick go with curves - I'll have another go. No masks applied. There's clearly a lot more that can be done with these images.

Couldn't resist one little tweak - applied curves manually instead of auto-stretch giving these images.

Think that's enough for today I'll look into other combinations in PixelMath tomorrow.

Images look fine for registration but rather "washed out" - not much colour contrast. Applied DBE and LinearFit, then combined colours with PixelMath. LH image is tri-colour using equal weights plus SCNR. RH image is bi-colour using R=H, G=20%H+80%O and B=O.

Found my silly mistake!! Picked up the wrong set of images after Dynamic Crop! Now trying again. I've checked that the images I'm using now are registered. PI has the useful property of showing the top image partly transparent when moving it - it's possible to see the underneath image through it and see the images exactly line up as the frames are aligned Clever stuff - the more I use PI the more I like it DBE next...

Back a few steps I guess to before Star Alignment. That's all the processing I've done today!!!

Went on to apply DBE which was successful then on to combine mono images to form a colour image. Firstly, I tried using just Ha and OIII as the SII image is very poor but I don't think the result looks right. I suspect the registration in Star Alignment. Then equal H S O followed by SCNR as the image was very green. The second image confirms the lack of registration I believe.

Yes, that's what I did. Tried again and it worked properly.

Very light rain, moon just rising, oooooodles of cloud...

The snow has stopped and there's just cloud. The droplets have disappeared from the dome

I'm trying to make a colour image from my three NB images using the Light Vortex Tutorials. Firstly, preparing the images for combination. Ran the Star Alignment - no problem. Now I'm trying to do the Dynamic Crop. Worst margins were on the SII image so used that to go by, dragged the instance to the desktop, then applied the process to the three images. The result I got is shown below. That is after applying Zoom to optimum fit for each image.

Heater working - the drops have dried off the leeward side of the dome (the side sheltered from the wind). This lens gives a FOV of 185° and goes just below horizontal. Round the edge to the south (from E round to W) is the next door fields, E-NE is the snow covered apex roof of my observatory, NW is my bungalow, SW next door house. And the mast to the NE carries the wind instruments for my weather station.

Think I'll have to look at the source code for the INDI driver for the camera and see if I can reduce the exposure. This driver will only go down to 0.001s = 1ms whereas the camera goes down to 32µs = 0.000032s. The above images were captured with all the camera controls at minimum - gain=0, brightness=0. Changing gamma doesn't help. There is no aperture control on the lens. Of course, this ASC is really only intended for night viewing but until I can get a daytime ASC done, this is all I have for daytime.

It's asking a lot when there is actual precipitation landing on the dome.

Snowing here so I thought it might be a good test for my "raindrop drier" high power dew heater. Let's see how it copes with this lot. Melted the snow already

I'll see what I can find.