Xiga

I was really hoping to get more data for this, but the weather just hasn't been playing nicely. We did actually have an amazingly full clear night last week (and with no moon about either) but as luck would have it i was sick at the time and could barely lift my head off the pillow nevermind lift the gear downstairs! In any case, it now sets below the roof of our house too early in the evening to get much in the way of data, so i'll have to wait to next year now to get some more RGB (especially the Red) plus some Ha to help give the edge of the Bat more definition. Until then, i decided to just go ahead and process what i have for now. The Lum was captured over 2 nights in late Sep with no moon about. The RGB was captured over 2 nights in early Nov, with a fairly bright moon about (although low down). In all honesty I really didn't think i'd be able to make a presentable image with just 30 mins of Red data, but i'm happy enough with how it came out, all things considered. SW 80ed; Qhy268m; HEQ5-Pro Lum: 125x120s (4 hr 10); G: 20 x 180s (1 hr); B: 20 x 180s (1 hr); R: 10 x 180s (0.5 hr). Total: 6 hr 40 Stacked in APP and processed in PS. Starless processing (using StarXTerminator) used to bring out the dust, and NoiseXTerminator used for NR. C&C welcome, and thanks for looking 🙂

Really nice to meet up with you too Adam. It was good to talk processing to someone (other than myself! lol) for a few hours. Hopefully i didn't ramble on too much 😅 You're off to a good start. Are you using the option in APP to separate out the Ha and Oiii signal into 2 mono stacks to process independently, or are you just integrating it into one colour stack? It's been a while since i did any bi-colour work with OSC data, but i always found that having the 2 stacks gave more control.

thanks mackie. it came as a nice surprise to me too! cheers Lee. I've used this method before in the past, but i was never totally satisfied with it to tell you the truth due to the limitations of the software available at the time. It's only now with the much improved StarXT (or Starnet++V2) but especially NoiseXT that i've now found it possible to push the data far enough without ruining the image thanks Adam 👍 I think for any image containing dust (no matter how much) using a starless image to help boost it is always worth a go now. it might not work on every image, but it's always worth a shot, especially now we have software that's able to give us clean starless images and an effective way to deal with the noise thanks mate! you're absolutely right about camera technology, it really has come on a lot in recent years. I'm super hapy with how the 268m performs, it definitely has made processing more fun for me in my Bortle 5-6ish skies. Thanks Olly, that means a lot! 🙏 By the end, i'd been staring at the image for so long i'd forgotten just how much the addition of the starless processing had transformed it. It was only when i looked back that it hit me, and that's when i had the idea of showing it as an animation.

Thanks Adam. 🙂 For a long time, while i was processing it, i wasn't really happy with how it looked. Then when i removed the stars and boosted the starless image, it suddenly came to life. I thought it would be fun to show a quick animation. Here is a gif which starts from the image right after doing the LRGB combination, and ending at the final image. No intermediary processing steps, just a smooth transition between the two. Note, i had to downsize it by 50% in order to keep the file size down. Ignore the slight posterisation effect, this is just a side-effect of converting the image into a gif.

Very nice indeed Carole. I love those gold and cyans! I think you could safely lower the black point a tad more, just to darken the sky background and help the nebula stand out a bit more. ps - I prefer the one without the star reduction. It looks like this was shot with a narrow bandpass Ha filter, is that right? I've found that since getting one of the 3.5nm Baader Ha filters, i now usually only need to do a very small amount of star reduction.

Good to see you back posting images again Adam. I took a break capturing data between Feb and Aug but am back at it now myself. For only 40 mins with the 2600mc it looks really good! You can tell the Ha has made a real difference and added some nice detail inside the nebula. All it needs now is some more data and you'll have a winner. ps - The stars look a bit elongated from bottom-left to top-right. Given this is a tight crop and you're using a CC, it's unlikely to be coma or tilt. Do you think it was a collimation issue due to using the Ocal?

For anyone interested in how the 'unscreening' method of separating stars from an image works, here is a video where Bill Blanshan (the guy who came up with it) describes it. The video itself is actually about star reduction, but he also shows how the method is superior for extracting stars from an image. The whole video is worth a watch, but the specific section on the method above is from 13:40 to 17:20.

Glad you liked the new method of adding back in the stars Olly 🙂 I'll post a link to a video which helps to explain how it works (although i have to admit i don't think i fully get it myself!). I'll add it to the thread above for consistency.

Astonishing set of images and level of dedication to get to 100 hrs on a single target. Congrats! My personal favourite is the 1st, but having never seen M33 shot in SHO before i have to admit the last one is doing it's best to woo me!

Thanks simmo! 🙂

Shot over 4 nights in Aug & Sep, 3 nights for the Lum and 1 night for the RGB, all with pretty much no moon from Bortle 5/6 skies. I've been processing this on and off for the best part of a week and a half now, as and when i get a chance late at night. For whatever reason, I was able to get to 90% of the finished image pretty quickly, but i then seemed to struggle when it came to settling on the final brightness, saturation, and overall level of star reduction for image presentation. I was initially worried that i wouldn't have enough RGB data to bring out the colour. but as it happened i had to actually dial down the colour in the end, which really surprised me. I have to say, the new tools for star removal (StarXTerminator) and noise reduction (NoiseXTerminator) really are amazing, and allowed me to push the data further than i would have been able to before. Details below: L - 164 x 120s (5 hr 28mins). Astronomik-L3 R,G,B - 19/18/16 x 180s (2 hrs 39mins). SVBony filters Qhy268m. Mode 3 (Extended Full Well). Gain 16, Offset 25. -5C. HEQ5-Pro\SW 80ed\OAG & 290mm AstroPixelProcessor used for stacking and light pollution removal, Siril used for PhotometricColourCalibration, and Photoshop used for everything else. The sheer number of stars in the field was overwhelming at first, so i had to use starless processing to help tame them and boost the dust. It's amazing just how much dust is there, hiding in the background, and only visible once you get the stars out of the way. Up to now i've never bothered even trying to shoot anything dusty, so i'll definitely be trying more now in future. In fact, i managed to also grab about 4 hrs of Lum on B150 (the Sea Horse Nebula) in the last couple of weeks, so fingers crossed i can get some RGB on it in the next few weeks otherwise i'll have to put it on hold until next Autumn. Thanks for looking guys, and clear skies! 🙂

Nice ghost Olly! Looking forward to seeing you go through your (no doubt vast) back catalogue! Did you know, there's actually a better way to add back in the stars than just using the original image in Lighten Mode. I'll explain the manual method below: 1. Put the original image (ie with stars) on the bottom layer. 2. Put the Starless image on the layer above. 3. Invert both layers. 4. Set the top layer (the Starless one) to 'Divide' blend mode. 5. Do a 'Stamp Visible', ie CTRL+ALT+SHFT+E to make a new layer, (i like to do this rather than Merge Down as it keeps the bottom layers intact). 6. Invert the top layer. This is now your 'Stars Only' layer. Note, this stars image is superior to the one you get by just using blend mode Subtract (or Difference) between the Original and Starless images, as this new stars image contains the full brightness of all the stars. 7. Finally, when you're ready to add back in the stars, just add the layer and set it to 'Screen' blend mode. Try it and see. I found it was a game changer for re-adding stars in a starless workflow. ps - The method above works just as well for those using Starnet++V2 btw, but for those using Star-XT and Photoshop you're better off just using the PS action that Russ Croman has created here https://www.rc-astro.com/StarXTerminator/UnscreenStars.atn.zip The action runs StarXT and removes the stars and puts them in their own layer all in one click.

Excellent write-up Adam. How did it go on Saturday night, did the Ocal lead to better shaped stars? I still haven't done anything with the old Vixen R200SS i picked up a while back (unfortunately it will be a while before i can do anything with it, but i'm not in any great hurry either) but i did have the Ocal in mind for collimating it when that time comes. As soon as i saw it i thought it lookedlike a very neat way of taking the guesswork out of collimating fast scopes. Quick question, is it always the case that you need to align the outer 2 circles and then put the crosshairs over the centre point of the mirror, and just ignore the inner circle being slightly 'offset'? Or is it only certain scopes (e.g those below F5) that you need to do this?

That's lovely Rick, i really like that! Nice and colourful with lots of detail in the nebula itself, and the stars look great too. I've been processing an LRGB of this one myself this week, though only with a wee SW 80ed. Not quite there yet. Managed the first 90% of the processing quite easily, but for some reason am struggling with the last bit, mainly in regards to how bright the final image should be, and how much (if any) star reduction to go with. Should hopefully finish it soon. Cracking image!

Love this. The level of detail is insane. The resolution of the big scope being put to good use here. Very nice processing too. Great work!

I got some Lum data of the Cocoon Nebula a few weeks back, and I experimented with Mode 3 (the extended full well one) at a Gain of 16. I think there's a bug when using Gain 0 in that mode, so people recommend using a low Gain of at least 14 instead. I thought the data looked good tbh, although I don't have any data to compare it to so it's all fairly subjective. These cameras have pretty low RN even at low gains. As long as you are able to sufficiently swamp the RN then it shouldn't make any difference in the final image. I was shooting 120s subs and still able to swamp the RN by more than a factor of 10 so I'm going to give it a go for a while and see how I get on.

Thanks mate! I think having short 60s subs helped when it came to bringing out the detail in the core. Saying that however, i think i'm going to experiment with slightly longer Lum subs (120s) at Gain 0 next time i'm shooting broadband. I'm curious to see how they come out, given the much higher well depth.

thanks mackie! 🙂

Thanks 🍅 😄 Cheers Dan. It was a nice surprise to me 🙂

Thanks Bryan. It's one of my favs too 🙂 The wee ed80 doesn't really have the FL for these types of targets, but with the small pixels of modern CMOS cameras you can still get some surprisingly good results just by cropping in.

Hi, Apologies for posting this one out of season! I shot this back in early March, but only processed it this week. Truth be told, i've kind of lost my AP mojo a bit this year due to technical issues, so I decided to take a break from the hobby right after i shot this. I've recently taken it up again, and was out getting some Lum on the Cocoon Nebula a few weeks back. The data capture issues remain unfortunately (25% of subs unuseable) but what i did get i was happy with, so with any luck i might still have time to get some RGB over the coming weeks so i can actually make another finished image. Between work and the kids I think my current hit rate is only about 5 images per year lol. Details: Qhy268m, -5C, Mode 1, Gain 56, Offset 25. Calibrated with Flats, Dark Flats, Darks and a BPM. Skywatcher ED80 w FF/FR HEQ5-Pro OAG & ZWO ASI 290mm mini Lum: 516 x 60s (8.5 hrs) RGB 30 x 180s (1.5 hrs each) Stacked in APP, processed in PS. I'm still getting to grips with LRGB processing, this is only my 2nd one so far. The SVBony filters revealed their budget roots in the Blue and Lum subs, where the stars were noticeably bloated. I really need to get a Baader IR/UV filter to put at the front of the imaging train to fix that! The camera is very good i must say. I'm more than impressed with it. I wasn't expecting to capture any of the faint tidal stream that loops around the top of M63, but when i came to process it i could clearly make out some of it, even if it was extremely faint! With just 80mm of aperture and a relatively slow F-ratio of 6.3, not to mention so-so skies of Bortle 5/6, i'm very impressed that the camera managed to pick any of it up at all. I've included a downsized inverted image of the Lum stack below that's had an Equalize adjustment in PS which just about shows it up. The small pixels of the IMX 571 sensor also allows for some nice cropping, so i've included a 100% crop of the galaxy itself. Clear skies all!

It comes with a 30 day free trial, so nothing to lose. Honestly, give it a go. I think you might be pleasantly surprised.

I think that's pretty amazing Rodd. The colour looks spot on, and the detail you've captured is very impressive for a galaxy of this size. As you say, the background is a bit too dark. Have you tried Russ Croman's NoiseXTerminator? If not, you should definitely give it a go. It's a game changer in terms of noise control. You will probably find it allows you to use a higher black point than you've been used to.

Just beautiful Maurice! The Nikon is a great match for the Tak and still gives many modern cooled astro cameras a run for their money when paired with a good scope and a skilled operator.

Just to echo Peter's comment above Carole, i also love the colour palette on this one. Bright and colourful, right up my street i have to say! A special mention as well on the stars. They look especially natural, and not disc-like, which is so easy to do on NB images. 👏