geeklee

"Right everyone, it's time to head inside and process this. I've set up chairs behind my computer so you can watch me for the next X hours as I get this into something I think you'll really like..." 😅

You should also have the option of using the Live Stack feature too. This could give you a few more options. Maybe the shorter subs but more of them or some longer ones for certain targets. A little reading required and by the sounds of it, if you can get away without calibration frames it would be easier.

You've recovered a lot from the description of the conditions @Clarkey. There's plenty of the larger structural detail and the colours are helping that separate out nicely. The stars are quite flat and grey but appreciate this may be on purpose if you're trying to suppress them a lot. There's some coloured edges so they must have been shining nice and bright earlier in processing?

That's looking great Adam. Fantastic colour and detail. Knowing the weather, it'll let you get all of the third pane but just the Ha on the fourth or something!

Fingers crossed you get a resolution. Do the Gain and Offset values in the FITS file header of a Lum sub match what you'd set? No problem, I only threw SharpCap out there in case you used it for Polar Alignment. It'd be quick to connect the camera to this for a few minutes to test.

HI Neil - for the RedCat 51 - at least the current version - you can unscrew the M48 adapter piece at the back and it will reveal a place to screw in a 2" filter. Then replace this back on the RedCat and you've still got your M48 adapter to connect the camera - assuming it has M48, which it seems to above? Picture from WO here showing filter position. Due to the Redcat's design, a fixed back focus isn't the case. I like the information in section 4 here (scroll down) - there's a nice diagram from WO too 👍 I still aim to have my cameras around 55mm (but have had 53, 54 & 56 with no difference).

Using Statistics (16-bit [0,65535]) in PixInsight or the Pixel Aid tool in Apt will give you an idea (For the Pixel Aid tool, ensure it shows "FITS Mode". You get this by double clicking the image - e.g. dark frame - on screen so it zooms in). ~1920 should be offset 30, ~512 should be offset 8. The Pixel Aid below is on a shortish Dark Flat sub as it's all I had on that machine that Apt could read. My 300s Master Dark in PixInsight shows similar numbers for average/median. Apt: PI: Your file earlier was around 512 (offset 8).

Sorry about that Graham. Did the software meltdown include reinstalling ZWO drivers (both native and ASCOM) or just getting Apt up and running again? Nothing unusual when you connect the camera and set the gain (e.g. it sometimes resets)? Very strange it's just the Lum - it kind of pulls you away from thinking it's camera/hardware related. Can you take a Red sub, it's OK, then immediately take a Lum sub and it's bright white, then go back to Red (for example) and it's OK again? Do you have any other software you can try to take a Lum sub with - Sharpcap maybe (or another capture prog of course).

I had a look at the FITS header for the individual dark frame. Example (I've removed some of the FITS info like your latitude and longitude) I use Apt for my calibration frames and use the ASCOM driver - the defaults for unity gain (120 - which you're also using) give me 30 as the offset. Perhaps the native ZWO driver is giving you 8.

Great to see this version of the data appear Adrian, excellent job. I like the colour palette and you went all in with the full 183MM resolution - good on you. That faint OIII is popping up everywhere - I'm glad you managed to add in the extra 7 hours. The reduced star field really shows off the nebula. Best work out the next scope you'll need to do PK178-02.1 justice.

Thanks @Adamar98 Thanks @Clarkey I think your 600D version was a superb image. Equipment differences always come into play. Thanks @carastro For this one, it wasn't too bad (certainly not like a previous collaboration from late 2021 of a region in Cepheus - four panes with Ha, OIII and SII!) as most of the data was from the Samyang lens with a 183MM camera. Seeing the OIII come out in this image was a real treat especially in the very faint regions.

This seems high for Luminance with the 1600MM at unity gain. Looking at your site, you are taking your Lum typically at 300s (I see some 60s Lum too on a few images) with Ha subs typically at 10min/600s. It might not be as simple as this of course but wanted to rule out the obvious - I remember accidently taking a very long Lum sub in quite bright skies once and it came out grey and the histogram on the right. With this though, I'm not so sure it could happen without being close to the moon with the longer exposure 🤔

If you've temperature, gain and offset matched and they don't show any abnormalities then they should be fine - just try calibrating a Light sub with them. You can always retake darks. I had a look but unfortunately I can't directly compare to mine as you're using offset 8 and I'm using 30. Your median values look inline with the offset. Your starburst certainly looks like mine Just make sure your lights are offset 8 as well, if you're using that. Hope this helps.

For the horsehead image - halos aside - it looks like the Ha and OIII are not aligned. I've drawn a few arrows showing where the OIII should be matched with the Ha. If I extract R, G and B then star align G & B to R and recombine I get: It's not perfect of course but hopefully shows how out of alignment the channels are. If you can fix this first for your masters, it will at least bring the image together in a uniform way and let you go from there. Hope this helps.

Thanks for the positive comments Olly (@ollypenrice) and Steve (@tomato). The starless version is very nice and has that little bit of extra depth that a busy starfield can sometimes hide. The Samyang is an easy lens to recommend - very particular spacing with an astro cam and filters but once you're up and running you'll have a lot of wider field options.

Thanks for the comments @Adreneline @Sunshine and @Tom OD. Tom - the 183MM camera gives up a lot of FOV with the 135 but gives you back some surprising detail. Here are a couple of Ha crops at full resolution (I resampled during post processing).

This image was another collaboration with @Adreneline where we shared our Ha and OIII. It comprises a total of 23.75 hours of Ha and 11 hours of OIII. The Ha data is a mix of mosaic data and "all in one" where our differing setups attempted to cover the whole of the nebula. The capture for this was started on 17th November 2021 and include subs from 17Nov21, 05Dec21, 07Dec21, 10Dec21, 28Dec21, 01Jan22, 03Jan22, 06Jan22 and 21Jan22. Most of the data was captured by both of us with the Samyang 135 @ F2.6 (with stop down ring). A little Ha was done with my RedCat. I'm not sure if one or both of us are finished shooting this, but after many attempts I've settled on an image I don't want to immediately throw in the bin! If you've imaged this yourself you know how weak some of the data is and how it feels like there's even more compromises than normal! My main trade off was leaving a busy starfield - which I personally like as I think the nebula still stands out enough. There's a lot of intricate detail within this nebula that I want to explore a little closer at a later date. Thanks for looking!

If that doesn't work, the next thing to look at is LNC (just above MBB). Again the tooltip is concise and gives you good starters. I typically use LNC initially but if it's multiple nights in the same pane and lots of panes then... If you're still having trouble after this then the next level is looking at each pane - cropping, gradients/background and matching levels to other panes - then combining.

As a first pass, ensure you've ticked MBB under Integration. The tool tip explains things well but try 10% as a starter. There are a few other things that can help - both settings in APP and approaches but start with MBB. Are you choosing Mosaic in Registration? EDIT: that's looking good already!

I would have loved to get a better first light, but you've got to work with what you get. Here's a couple of common targets from 21st Jan, both in Ha. Fingers crossed for clear skies soon to get some decent integration done. Thanks for looking. StellaMira 90 + 294MM Pro (Baader UNB 3.5nm Ha) IC434 (15x300s) A real mix of sub quality. M42 and M43 (30x120s)

That's a cracker and just stuffed with different areas to enjoy! A great example of the extended nebulosity from the Rosette and it's interactions. APP just got it stitched! A smidgen of black to fill in around the periphery 😅

Thanks Pierre. No plans at the moment but it would be awesome to get an HaRGB image - it's the constant battle against clear skies really 😐 Thanks Adrian. Me too, I really like where a bit of this is shown in an image of Orion - close in on something or far out framing things. Here's one more wider shot that includes the Jellyfish nebula (IC443). M35, NGC2158, Monkey Head nebula (NGC 2174) and Lower's nebula (Sh2-261). This is 3 panes with the Samyang and 183MM - between 15 and 30 minutes per pane so not much.

Recent subs suggest you've hit a sweet spot with the latest setup. Nice shot with the "under the L" focus clear 😉 Adding one more to the thread, here's a six pane mosaic of a small piece of Orion. Around 5 hours of data captured across a few nights - not all of which were very good quality - with a few patchy areas where I didn't get as much data on 1 or 2 panes. The Samyang had the 183MM camera stopped down to ~F2.6.

Super image again Adam. I prefer the added touch of stronger OIII but the Noise Reduction (NR) reduction looks a little stronger here - personal preference of course, but I thought the NR in the first, with a little grain, was fine. Maybe somewhere in between on NR? It looks great at full resolution and should make a cracking final mosaic in 2030 when you get the skies 😉 😅 One thing to keep an eye on is some of the brighter stars, they have some small artefacts around them, perhaps from Starnet?

I was expecting something to appear much later than this - maybe even winter 2022! Fantastic final image.