tooth_dr

Extensive workflows on the website https://www.astropixelprocessor.com/mosaic-tutorial-milky-way-to-rho-ophiuchi-by-mabula/

There are several video demonstrations of complete processing of an image from start to finish. For example, the MW image he stitched together at the start is there on his website. The videos last 30+ minutes and would be similar to that talk he gave tonight. Well worth a look if you are genuinely interested in finding out more. I really enjoyed tonight and finding out about the much awaited comet feature

Nah that’s amazing. I’ve started doing a few solar timelapses and appreciate the huge effort they goes into them.

Just to reiterate I’m asking about exposure lengths not total exposure. You will obviously want more total exposure time for luminance, but I was just wondering why choose to expose individual subs for half the time when you are already only getting a third of the signal of lum / broad band spectrum (approx)

Indeed, thanks for that! I’m just trying to assertain why you would choose to expose for less, with filters that will inherently let less signal through then luminance

Thanks Steve. I don’t mean you want 2x the total exposure for RGB compared with Lum. I mean that your individual exposures should be twice the length of the luminance subs, or at least the same length. I’ve produced images with as little as one or two subs from RGB channels but a good luminance data set.

APP is simply fantastic and the personal support by Mabula himself is second to none.

That’s a very nice image! I image at 215m which is considered high for here 😂

I've been reading exposure times, as I'm just getting started on LRGB imaging, and thought RGB should be the same (or 2x longer ) than luminance, so I wondering what was the rationale for shorter RGB subs. l'd have thought that it you can get 10 mins on luminance then you would get 10+ minutes on RGB, and wouldnt be limited to 10mins on H-alpha.

A few months ago I bought an M42 adapter to connect a nikon lens to my QHY9 CCD. When I added in the filter wheel to the imaging train, the lens was a few mm too far from the CCD sensor and I couldnt get it to focus at infinity. I set about working out how to get it to focus. I figured out that if I could screw the whole adapter into the filter wheel then I could gain probably 5mm of back focus. The current nikon lens adapter was an M42 thread, but the body itself was large enough to cut an M54 thread externally. I could then thread that adapter into the EFW casing. I had to be careful not to foul the filters inside at the same time. This adapter replaces the M54-M48 (or M54-M42) adapter that comes with the EFW. I couldnt do this myself so I sent a fella I know a message about it, and he was happy to try and sort it out. We met up a couple of times, and he took some measurements, and set to work on it. I wasnt in a panic, so a few months went by, with me finally getting it 3 weeks ago. In between times I bought another used QHY9 and matching QHY EFW. It is a 5 x 2" wheel which is perfect for the KAF-8300 sensor size at a potential F2.8. I had a luminance filter already, and I picked up a 2" Baader Ha filter off here a couple of weeks ago. I'm still looking for RGB filters. In between times I had lent the QHY9 to xiga off here, so when he was finished with it a week and a half ago, I got it back and set about connecting all together. I wasnt sure if it would focus at infinity, but initial testing looked positive. I had my first session on Thursday night with it, and it focused fine at infinity with the 180mm lens at F2.8, with just the expected amount of extra travel past infinity. I 3d printed a microfocuser but it's a mm too narrow in diameter to fit over the barrel, so I might just rub it down later with a file to get sufficient clearance. It's virtually impossible to turn the focus ring by hand at small enough increments, but I got as close as I could with a Bahtinov mask. I dont have any calibration data yet - I went to get it today but the camera is sitting at 19 deg C and since I run at -20 deg C, it might just push the camera power a bit too far for my liking as it only does a -40 delta T. There is no longer a locking button that normally locks the lens in place. I have the camera supported on the dovetail so there is no pressure on it, and it cannot easily turn. The overall fit of the adapter is tight, and not loose like the way a normal camera lens feels when you connect it to a camera body. My friend could have made it, but it just wasnt needed. I'll post a few images of the adapter, how it was made up and how it fits into the imaging train. I painted it black and rubbed it down with fine sandpaper to prevent reflections. My friend had planned to anodise it for me, but his factory machine was out of order, and with no repair timeframe, I was happy enough to paint it myself. The image itself is 6 x 20 minutes, 7nm H-alpha filter. QHY9 mono KAF-8300, with Nikon 180mm lens at F2.8. Stacked in APP. I didnt get the pre and post meridian flip platesolving done, so the frames dont all match up, but you can see the FOV of the KAF-8300 and 180mm lens. I plan to run this alongside my Epsilon and ED80, which both have KAF-8300 sensors, and try to produce a variety of views of the nebulae. Hope this is of interest to anyone attempting the same thing. It also works with my Atik EFW2, which is 22mm thick. Original purchased Nikon lens to M42 adapter off ebay for £10 (or less cant remember exact cost) - it was used for the lens connecting parts New adapter being made, my friend informed me he turned all the threads by hand. Completed adapter: A few photos of equipment attached:

Its interesting about your exposure times RGB subs. Do you bin 2x2 the RGB?

Well deserved. Incredible image.

Would it be an option to buy one NB filter - Ha. The Baader 7nm filter works down to F2.8. If you buy it in 2” then it would be one less filter to worry about if you switch to mono?

Very nice Sean. You have a filter wheel between the lens and camera?

Cheers Alan. It does look really blue. I tried but didn’t get that result. Overall your colour adjustments looks better 👍🏼I wonder would it be hard to get the background a little more neutral and keep the ion tail blue etc.

Thanks Ciarán. You’re guide was helpful. I stacked separately comet and then stars. I did 20+ stacks in DSS and ended up fluking a comet one that turned out ok. Most were mush. I ended up with 106 subs in the stack. I might tackle the background

Looking at the weather etc, I think I'm done with Neowise and to be honest quite satisfied that I saw it, imaged it, and shared time with friends new and old.

Uncropped version. I have some artefact running across the middle of the sensor, so I cropped the original (above), but i like this version.

Final image of Neowise, over to the experts now 🤣 I've looked at my individual subs, and it's really hard to see the blue ion tail against the blue sky.

LOL yes only messing, I had 160 subs

1. OSC useful for planets, mono better for solar and probably moon too 2. uncooled, you don’t need cooled for planetary imaging 3. If entirely planetary then a large chip isn’t necessary but you have mentioned lunar and solar. In this case you might want a larger chip. I have used a ZWO 120MM for planetary/solar/lunar. It’s cheap and effective and well within your budget. 4. You mention you have CMOS cameras. What model? Why can’t they be used?

^^^ For wide angle at a budget of £100 - it’s tight. I used to have one of those lenses above. Used it in Iceland for widefield shots. It’s slow enough but decent. Is something like that of interest?

https://www.mpb.com/en-uk/used-equipment/used-photo-and-video/used-lenses/used-nikon-fit-lenses/sigma-10-20mm-f-4-5-6-ex-dc-hsm-nikon-fit/sku-1011545/?gclid=CjwKCAjwx9_4BRAHEiwApAt0zkGsKHp1yU5uLrEtM_tlYhZNrC98Y9kc4jkN_gY_IhK3vL9HRyF0ZRoCeU0QAvD_BwE&gclsrc=aw.ds

This is me done now I think, I've spent three evenings on the processing and this is the best I can achieve.

Very interesting Francis, thanks for sharing. I had noticed a similar red streak, but it turned out it was @Xiga walking past the camera last Sat night 🤣🤣