teoria_del_big_bang

I think the idea is to separate he stars and nebula so you can stretch the nebula without over stretching the stars so they are saturated and take over the image detracting from the nebula, Also to do some colour saturation on the nebula without affecting the star colours without the need to use masks which are not always easy to create for all stars. So with that in mind it is done early on in the post processing and I usually do this in the linear stages. Not sure why you cannot get it working in PI though. Are you using Starnet2 ? Maybe explain what the issue is, that you cannot download it so it appears in the process menues or that when you use it it fails in some way ? Also maybe try StarXTerminator, I am finding it works better than Starnet2. Steve

Wow what an amazing project 🙂 Steve

Thanks for that, it is just something else to fit in the train behind the reducer so I might have to leave my rotator out, although probably not an issue as most targets will fit in the FOV without having to rotate to fit it in. Yes that makes perfect sense to me now why it is necessary. Steve

Well that's the current thoughts, but probably will not happen as quick as I would like - need to acquire the funds first thing and then see what stock is available (I think the scope if I go 8" is not an issue although tempted by the 9.25" but not sure what I really gain between the two scopes, except a lot more weight to guide and it is another £1K more so maybe stick with the 8"). Also it seems most seem to go with the OAG and not a piggy-backed guidescope which is all new to me. Steve

Looking at what others had done for AP yes I thought that was the best option, unless there is a better way. Steve

Well after looking about a bit more it looks like the best option is a Celestron Edge 8". I know there is still collimation but it looks to be easier than the RC and from reports stays in collimation well. So the next thing to look at is what else do I need. There is a dedicated 0.7 reducer but the blurb seems to say that for flatfield this is not required so is this just a genuine reducer and not a flattener / reducer ? Should I go with this reducer from the start rather than finding I am better off with it and then introducing it to the image train ? Also, fitting a motorised focusser does not seem to be too straightforward and many seem to think the Moonlight is the only way to go (or a FT). Anyone on SGL able to help me with their setups of this scope ? Steve

On reflection I probably was a bit quick to say sub £1K , I sort of stated this thinking in the end I would spend more anyway but to tell myself that was the original budget. I probably would have to spend nearer the £2K and all along was very impressed with the Edge 8". Steve

I understand there are a lot of choices (if you can find stock anywhere 🙂 ) hence my indecision. Budget I would say under £1k but could stretch a bit if necessary. Payload, according to specs is 27Kg, but unlike some mounts it does not state different payloads for visual and AP just the one 27 Kg. I was erring towards a 150 frac but just wondered if I would still end up over-cropping the images. Steve

Currently all of my limited imaging is done with my Esprit 100ED + QHY268M. And for many DSO's it works well but when it comes to galaxy season for me it is a bit of a waste of time due to the FOV. Also it does not yield great results for smaller DSO's like dumbell and bubble etc. I did buy a RC6 to hopefully get a better FOV for these objects but after a year I am still struggling to collimate it properly and am maybe thinking I could do better with a different scope. So any recommendations ? Ideally I could do with something not too expensive, easy to collimate if a reflector, something that my CEM60 mount will handle with ease and I would want to use it with the QHY268M or possibly the 1600M. Steve

I don't think an apology is required 😂, always great to view your images Olly. Steve

Welcome back Ron. I don't think too much has changed to be honest, there was some big changes around being allowed on the classified section but that should not affect you, otherwise much as it was , just be courteous to others, no swearing or politics and you should be fine 🙂 Steve

Just came across this SCRIPT while Googling, can't say I had seen it before. Basically it sort of looks along the lines of WBPP but reports that it can do all the processing from the initial lights, darks & flats through to final image. I was very sceptical but thought I would download and let it do its thing on a computer whilst I got on with other things. There are a host of possibilities you can setup, far too many to list so on the face of it seems quite complicated, however, undeterred I added just 3 NB already preprocessed images (pre processed in WBPP) and flicked through the options and ticked a few boxes, really I did not pay much attention to what I was doing as I thought it would not yield great results without putting a lot of effort into selecting all the right options. Then I pressed run and well in not too long a time (42 minutes) a SHO image was on my desktop and to be honest it had done a pretty good job. Left is the autogenerated image and right is one I did earlier. So for a load files up and let it go script I think looks promising. In all fairness I have not studied all the options or read any instructions so it is probably capable of much better images. It is supposedly capable of RGB, LRGB and various NB paletes. One great aspect of this is it has a preview window to see the image developing as it runs various processes. It seems to allow the use of pretty recent new processes such as NoiseXT, StarXT. I did load up 3 already calibrated images, calibrated in the fantastic WBPP so not yet tried loading raw files but I do not see why this also would not work (it may even use WBPP to do the pre-processing) Also I admit the image I processed may not be the best and is not my final image. I am not saying this is the way to go or in fact is for everybody as many enjoy the processing and of course you have much more control as you go through all the steps to enhance or tweak things, But it does have some very good uses :- It seems a real quick way to put some images together to see what your data is capable of and could be done all autonomously with very little input from yourself so maybe you can get an image in the morning after a session and a good indicator to see how good the data is. For those learning PI it is a great way to get a RGB image without much effort and at least see what their data is capable of and then they can maybe do it themselves and try to improve on the autogenerated image. I guess for those that love imaging but hate processing (and I think there are a few) then this at least may get them half decent images without too much pain. Anyway I cannot comment too much as I say I did not give it too much thought but it is certainly a script I will be experimenting with, but maybe not use for final images just an initial process to get an idea of the datas capabilities. Steve

Oh I have done that already don't worry 😱 Steve

There is definitely a free version, I think the subscribed one is just for organisations. Don't ask me the ins and outs of how to do it but I am sure it will work with Win7 and 10 but I say this with no certainty. Steve

Just been talking about this approach on THIS THREAD started by @carastro and this for me is a prime example of how it can help stop the stars overpowering the nebula. Both great images by the way but I much prefer the new version 🙂 Steve

Totally agree. But I think THIS great image just posted by @gorann is a good example of what I mean by some images being swamped with stars and the starless approach (albeit just during the processing not the final image) really helps. But having said that @alacant has a point and I guess the amount of star reduction is down to personal taste but as with a lot of things in processing often subtle changes can give better results. Steve

Oh I hope so, I don't have to move from Yorkshire then 🙂 So long as I can get NINA to update it to wipe during the dither. Steve

I don't do much 2D printing as I find the ink is much more expensive than the plastic for the 3D stuff 🤣😂 Steve

So the trick really does work eh ? Steve

When all the star removal tools appeared (or at least good working versions) I think there was a glut of actual starless images appearing but to be honest it didn't really seem to last that long as they were different but do look so unnatural. However, I do think star removal does have a place in processing for a few reasons. These are things I have read about and have been trying so it maybe there are other ways, or maybe better ways to do the same thing as I am still learning all this 🙂 Some images of nebula are swamped with stars and that does detract from the main target image and so some star reduction does help the final image (in my opinion). But for me even your image without any star reduction is not swamped by stars and looks perfectly natural and can still see the target. Some images with feint contribution from one, or more, of the filters, need quite some stretching to bring out the detail and it can help to separate the stars early on in the processing and add them back later to prevent the stars becoming saturated as an alternative to star masks. For NB images there is the opportunity to remove the unnatural colour stars if you managed to take some short RGB images just to capture the stars, and then use tose to add to the image instead. I also have used star removal on the luminance to bring out the detail of the nebula without swamping the stars. I think the latest star removal tools seem pretty good at not leaving artefacts on most images,. As I say this is very much my thoughts and these may not be the best way to achieve what I am after so would be happy for others to educate me 🙂 Steve

I have a fanless PC on the mount running NINA and wifi via remote desktop. There are lots of programs like Windows RD and I think you need Win 10Pro (or similar) to use RD, I don't think it works with home edition but other programs work well, I just like RD because I can easily use both monitors on my desktop whereas I struggled doing so with the other available programs. Steve

Quite true, maybe I will order a spare as well just in case 🙂 If these can image through the clouds then that is just what I need in Yorkshire, so long as it doesn't rain. Steve

Why do they never use round figures, it's always 99p not a pound isn't it, even at this price range why isn't it a round million ? Steve

New scope serving you well I see, that is another great image (or images). For me there is not much in it but if I were pushed I too would probably say the image without star reduction is the better of the two. I have not had a clear sky since coming back from Kelling (and didn't see much there either - maybe it's just me 🙂 Steve

Nice images and a good test albeit maybe not actually a comparison of mono V OSC but as you say it is a good test of your current OSC setup v your current mono setup. I think both are good cameras as for a long while value for money wise the 1600mm seemed to be considered one of the best on the market and for around the £1K mark (which it was before recent price rises) was a great buy. The 2600mm and other makes with same spec are a breed apart being a far better camera. But that's not in question. I am no expert at all so cannot really say for definite what path I would take given the same circumstances. But, this is one target and if I am right it is very strong in Ha with some OIII and very little SII emissions. The little bit of SII I think is mainly the very outer dust and there is definitely more thin stuff in the outer part of the nebula in the mono + filters image. So maybe it depends on what targets you want to image: For LRGB then the 2600 C is a clear winner. For Dual band Ha / OIII I think from your image and many others I have seen using the same dual pass then again I am sure the 2600C is more than adequate or better than the 1600mm + filters. I know many have good arguments why the mono is better but at the end of the day the 2600 is a better camera (greater sensitivity and lower noise) and more to the point much easier to use so given the choice if I had both setups would probably opt for the osc + dual pass filter approach. However, for any targets with very strong in say Ha but do have significantly weaker OII you may struggle to get enough OIII and targets with any SII emissions, you are going to miss it altogether. Like I say mine is not an expert opinion just my thoughts (I I could be wrong) as I have often contemplated going OSC, using a dual pass filter for NB targets but what has put me off so far is that currently most of my limited imaging time is from my backyard which is Bortle 4 with some LP but not too bad, however, I live in cloudy Yorkshire and I get very limited RGB imaging time as my few clear nights are often accompanied by near full moon and so generally look for NB targets if that is the case and so my main concern is not being able to obtain SII data, or indeed devoting more time to the weaker OIII channel if required. Steve