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Yeah, don't really want to have to change the cc due to the cost and the fact it changes the focal length of the scope.

Hi, I'm seriously considering doing this mod but have some questions regarding it: Firstly, thanks to using a low profile Canon adaptor (1mm optical length rather than 11mm) and an extension tube for the coma corrector to keep the 55mm spacing I 'only' need to chop about 12mm off my FT rather than the usual 25mm. However, when examining it ready to do the mod I spotted that its not just the FT itself that protrudes in to the OTA, but the outer part of the focusser as well (labelled B in the attached photo). So my question is, do people just remove the end of the FT itself (A in the photo) or also trim back part B as well?? Second question is regarding preventing the FT coming off the bearings when racked out for visual work. Looking at the design, the amount the FT can be racked in or out is controlled by the length of the flat section on its outer part that engages with the shaft for the focus knob. So one option would be to cut the FT and then drill and tap a small hole in the flat section of the FT 12mm from the scope end and put a small short screw in to act as a new end stop. It would stop the FT coming off the bearings but I've then lost 12mm of outward adjustment. Would one of these get that back for me if attached at the threaded outer end of the FT for visual? https://www.astroshop.eu/extension-tubes/ts-optics-extension-tube-m54-15mm/p,71886 Second option is to not remove the small section of FT that runs along each of the two bearings, basically leaving two fingers in place for the bearings to engage on. Advantage being its effectively no different for visual. Potential disadvantage being they may have an effect on stars. Has anyone taken this approach and can advise on imaging results afterwards? Thanks Ed

Thanks for trying Olly. Interesting comment about it being a bit cold. I've kind of taken spcc as gospel once applied and tried to stay true to that. The stars were on the money regarding following the expected plot lines, maybe I should try tweaking it a bit more and see what happens. Ed

Thanks, I tried something similar but it ended up as a horrible mess lol. I'm sure others would do better with the processing but I do feel I'm improving with pixinsight. The generalised hyperbolic stretch has become my new friend with regard to preserving colour during stretching. Ed

Happy to do that, though the file is rather large! Thank you, I'm very happy with it, just never satisfied lol! Have finally come round to the idea that I really need to chop the focus tube on the 130PDS to get rid of those bl**dy pacman stars! Something for this weekend maybe. File can be found here(FITS rather than TIF, hope thats ok): https://www.dropbox.com/s/amcmgxly9zgbtwf/Triangulum_Galaxy-session_1_session_2_session_3_session_4-NoSt.fits?dl=0

Yeah the more I think about it the more I realise that 4hrs is not that much actually (and that I need a dedicated astro cam lol!)

Just thinking about this a bit more - is there anything I can do by splitting the channels and boosting red somehow? I know its a bit of a cheat but just curious as to what the possibilities are other than gathering HA data.

ok, thanks Adam. Makes sense

Thanks Tomato, and no I'm not using an NB filter, only just recently ditched my CLS filter in order to grab more photons per hour. Something I don't understand with NB filters though, hopefully you can help.....if I can explain myself correctly lol. So I've collected 4hrs of data here, that should include 4hrs of HA as well presumably. So how do NB filters help above and beyond just getting more integration time in LRGB? (clearly they do - I just don't understand). Its not that they can somehow boost HA collection, just isolate that and reject other wavelengths? So how does that help more than just getting more RGB? I guess what I'm asking is how does gathering more HA specifically help more than gathering more LRGB which should include HA anyway? Thanks Ed

Hi, I've just finished processing some data I got on the Triangulum galaxy over January, but despite my best efforts I can't seem to draw out much HA. See below. I'm using SPCC and GHS within PI, and although very much a beginner still I can find my way round a number of the processes. This one was dynamic crop, DBE, SPCC, BXT, NXT, Starnet 2, GHS (starless), LHE (Starless), GHS (stars), Pixelmath to recombine. I've had 3 or 4 goes at it now and this is the best I have done so far, but would still expect to see more HA from my astro modified EOS 600D and 130PDS. If I look closely I can see hints of red throughout the spiral arms but not sure what I would need to do to draw that out without affecting colour balance. Its about 4hrs data, so do I need more maybe? Any pointers gratefully received! Thanks Ed

Ok, thanks

Thanks Michael, so to increase contrast should I be doing something different in GHS, just pushing the initial stretch more or something else? also curious about red being low, does SPCC not make R, G, and B correct relative to each other? Maybe I'm not fully understanding what SPCC does... Thanks Ed

I'm looking for a bit of collective wisdom from people on how I can boost the HA element in the attached image of the Triangulum galaxy that I'm currently working on. I can see there is more HA in there to come from the spiral arms as the pinks / reds are already subtly visible. I just don't know the best way of boosting them a little without adversely affecting the rest of the image. For info the processes I've followed to get this far are : DBE, SPCC, Blur X, Noise X, Starnet 2, GHS (Colour enabled) stretches, HDR Multiscale transform on the core. Any advice gratefully received!

That says highly elastic though, is that what we want to hold the mirror? Would assume that moves more during meridian flip?

I don't think the coating is on the back of the mirror though on the 130PDS? Not 100% sure though.

Thanks all, i'll just order the V-tech stuff then. Does have me wondering now though if aquarium sealant would work. That can't have any acids in it as it would pollute the water and needs to cure reasonably quickly and obviously designed for glass..🤔

Hi, Can someone confirm if this silicone sealant is suitable for mounting the primary mirror in the 130PDS? It says its 'neutral' but in what way I'm not sure... https://www.amazon.co.uk/Everbuild-700TTR-Roofing-Silicone-Sealant/dp/B0012RI3BI/ref=sr_1_11?crid=2F04891P5YQZ0&keywords=neutral%2Bsilicone%2Bsealant&qid=1673458332&sprefix=neutral%2Bsilicone%2Bsealant%2Caps%2C95&sr=8-11&th=1 Thanks Ed

Question on this, I'm lucky enough that work have supplied me with a good quality 34" monitor as I work from home most of the time. Can I use that as a flat panel if I also put paper / tee shirts between it and my scope? Thanks Ed

yeah image tags are the right way round 😕 Hadn't really noticed the salmon redness of it tbh, was more focussed on pulling out more detail from the core. Thats what you get for not stepping away from it for a while I guess! Still learning though and I'm sure I'll come back and have another go at it at some point but desperate to get new (better) data on it as well as I'm sure that will help. Colour balance has always been a pig with this datatset and when I asked here people suggested its likely the LP filter is the culprit, so I've ditched that as I'm 'only' in bortle 5 skies and PI should handle that with DBE etc. Thanks for the comments though, gives me something to focus on

So as part of my evaluation of whether I want to buy BXT and NXT I've been reworking some old data. Over the last couple of days its been Andromeda, which I took back on 2020. Lots has changed for me since then, includign the jump from PS to PI, but I have to say that BXT and NXT are game changers for me in terms of the time spent on processing. I really want to get some new data on this target as well to see if the pacman stars are as bad for me these days (I've changed my setup quite a bit since this data was taken) and I don't know how to fix pacman stars in PI yet. Anyway - here is my previous best attempt and todays back to back... Previous best Todays effort

Interesting, I will have to have a look at this.saw a video the other day by Sascha Weiss that said to use APP over PI as its stacking is better. I did think at the time he would be ripped to pieces over that lol.

Interesting, so would there be scope to run nxt before the stretch then a small amount later on towards the end? I too thought killing noise early was a good thing but have noticed subsequent processes introducing noise back in...

Hi, While evaluating BXT & NXT to see if I want to splash the cash I've been going over old data to try them. One such dataset is Andromeda. While doing so though I have found a bit of a funny that has me wondering if there is a prescribed order in which I should be running the above processes? The reason I ask is that I was running BXT & NXT before SPCC but this resulted in an image that was VERY red biased and the SPCC plots were all over the place. After some trial and error it would seem that NXT is the culprit, needing to be run after SPCC in order to keep a well balanced image. Is this to be expected or am I doing something really dumb here? Example screenshots below Actually - in uploading the screenshots I've noticed its even more subtle in that its only if I run NXT immediately before SPCC?!? Though the image where I did SPCC-BXT-NXT looks more washed out than BXT-SPCC or BXT-SPCC-NXT, but tis still way better than BXT-NXT-SPCC which was a red mess! BXT-NXT-SPCC: SPCC-BXT-NXT: BXT-SPCC: BXT-SPCC-NXT:

How are you finding WBPP Brendan? I've not used it yet, can't drag myself away from APP for stacking as its what i've got used to, and to be fair is very very good!

I managed to grab a couple of nights imaging in November, between all the cloud and rain we seem to be getting in southern UK still. This Pelican Nebula image is the result. Approx 6hrs of EOS600d data stacked in APP and processed in PI. I have used the trials of BlurX and NoiseX on this as well, probably a little too heavily but its enough to give me an idea as to whether I want to spend the money on them. Something going on with my stacking as some of the stars in the corners have trails (rather than my usual CC spacing egg shaped ones) and double diffraction spikes, yet others don't. Very odd but hey ho! Rough PI process was as follows: Crop, DBE, BN, SPCC, NoiseX, BlurX, Starnet2, GHS (Nebula), Curves (Nebula), GHS (stars), Pixelmath to recombine Nebula and Stars. JPG format seems to have washed out the colours though