Adreneline

With the likes of the ASI1600 bias frames are likely to increase noise in the image. @Jamgood has provided the info on a dark-flat. Adrian

The perceived wisdom is not to use bias frames - better to use flats, corresponding dark-flats and darks to calibrate. Adrian

As you say a promising start with your first light. There are numerous views on what gain and offset to use on all the forums. I've used a 1600 for a couple of years now and always use gain 139. I use the 1600 with an ASIair and ZWO set the offset at 50 with no means to change it. On that basis alone you might say 50 was a good place to start. Sticking with one setting makes life easier with calibration frames too. HTH Adrian

FIrst off this is a really good image of the HH with some excellent detail in the nebulosity and the structure of the HH. To me the main issue is the stars. You don't say what scope/lens/camera you used so I may be well off the track with my comments so apologies up front. I have had every problem going with RGB imaging, not the least of which was very different fwhm values for stars taken with each filter. I used to suffer from terrible 'blue bloat' giving rise to significant bluw halos around stars. I think it was either a feature of the doublet scope I used or a feature of the filter - I use feature as a euphemism for shortcoming. I managed to ameliorate these features by reducing the star sizes in G and B until they were comparable with R; it wasn't a perfect solution but it did help. You don't mention which software packages you use but if you use PixInsight you can remove the stars in the R, G and B channels and process them separately before recombining with the starless images. Working on starless images let you "work the data" more without compromising the stars. Without doubt you have lots of good data to go at so it is worth a shot. Adrian

Some people advocate using Screen instead of Lighten - you can do that in PixelMath with 1-(1-R)*(1-Ha). Personally I prefer the result using Lighten but maybe it all depends on the data. Experimentation is the name of the game! Adrian

Very nice image - I prefer the first one - great framing. I'm no expert but I was advised to add Ha to R using a Lighten blend (in PixelMath that would be max(R,Ha) - you can add a multiplier in front of the Ha if you wish, e.g. max(R,(0.7*Ha)). Once the Ha is added to R you can combine with G and B. There is also an NBLRGBCombination script but I've never used it so can't comment on how well it works. I'm sure someone who is an expert will pop up and advise. Adrian

Very nice Michael - I love the Rosette. Not sure about the star colours but on my MacBook screen there is a definite hint of green in the image. I ran it through SCNR in PI and to me it looked better and the stars too! Hope you don't mind. Adrian Rosette-aa-scnr.tif

Thanks for telling me that Peter - I hadn't registered the "may". I may switch one day but in the grand scheme of things - compared with the cost of all the gear - it's a modest price to pay each year. For me PixInsight represents about 4% of the cost of all of my imaging gear - Affinity is less than 1% - APP just over 1% per year. I can live with that. I understand the figures can look very different for others though. You pay what seems right for you and you take your pick of what's available! Adrian

I would be surprised if it doesn't fit. I have a Canon Samyang and I bought the Astrojolo M42 adapter before the Uranium235 became available. It is simply a case of removing three screws and the end plate comes off and you replace it with the M42 fitting.

I use three pieces of software to help me process my images (a) APP for all pre-processing, (b) PixInsight for most post-processing, and (c) Affinity for final cosmetic tinkering. If I could only keep one it would be PixInsight . I rent APP and like the ease with which I can carry out pre-processing and, the main reason for buying in the first place, the ease with which it handles mosaics. APP is regularly updated with enhancements and improvements as is PI and Affinity. One advantage of PI is the lifetime free updates once you've paid the initial cost; the same is true for Affinity but not for APP unless you rent. Personally I haven't missed the lack of manual - there is plenty of help online and in published magazine articles. PI benefits from a wealth of printed and online material, in particular the excellent online Light Vortex tutorials. Affinity is in the same category as APP - search and ye will find. I presume you have already tried DeeSkyStacker (free) and the likes of GIMP (free) for pre and post-processing. Adrian

Thank you Jody. Yes I am really enjoying the RedCat - it's a really nice piece of kit and I am very pleased with the performance so far. Thanks Tristan. I centred the image on IC444 but then decided to crop the image as well. Sadly the clear skies have gone elsewhere for the foreseeable (CO) future. That's very kind Adam. I tried HSO and HOS but decided SHO looked best in terms of revealing structure and detail. Thanks @glafnazur - glad you like them. Really appreciate all the comments folks. Adrian

This is 20 x 180s of Ha, OIII and SII; I also took 10 x 60s of R, G and B but decided against using them. Apologies for Tejat Prior and Tejat Posterior, they seem to wish to dominate the image despite all my attempts to contain them. Preprocessed in APP and processed in PI and Affinity. As always C&C welcome. Adrian

Thank you Paul. I was pleased with the way it worked out. As always more data would be good - along with being about 20 degress further south I always worry that I've over done the processing so I appreciate your comment. Adrian

Thanks Dave. We used to live in southern Derbyshire but the view to the south was over a major area of conurbation so LP was a nightmare - skies are much darker here so I thought I'd give it a go. Thanks Peter. I'm really pleased with my new RedCat 51 - it might not be an f2 Samyang 135 but it certainly performs well for f4.9 and I love the fact that my filters really are parafocal when used with the RedCat - not the case with the Samyang. Adrian

And there was me thinking you were deadly serious CS Adrian

Think someone other than me might need to second that - and even then I don't give much for your chances! Nice idea though Glad you like it. It's a tricky target from here because it barely gets above 25 degrees. Worth a shot though. Adrian

Thanks Adam - as always more data would be good, especially OIII, but I should be grateful we got a very clear night - a rare event! Thanks Tristan. Two clear nights on the trot and another one forecast tonight. No doubt that'll be our quota for February! Keep the faith! Adrian

Another clear night and this is 10 x 180s of SII, Ha and OIII; pre-processed in APP and processed in PI and Affinity. As always C&C welcome. Thanks for looking. Adrian

Thought I'd have another crack at it and this is how it came out: Enough for today. Adrian

Thanks Peter. The RGB image looks reasonable - given my limited rgb processing skills - the HOO image looks pretty reasonable as well - the trick is clearly bringing it all together and realsing a bit of synergy. More trial and error required! Adrian

Thank you Adam. M42 is a real challenge with it's huge dynamic range. I was reluctant to use HDRMultiscaleTransform to pull out the core detail because all too easily it can look sort of false and contrived. As for the halos .... ! Adrian

Really not sure about this one as my RGB processing skills leave a lot to be desired. This is 10 x 60s + 20 x 30s of RGB blended with 20 x 180s of H and OIII. Really not sure I used the best blend method but in the end I opted for the one that seemed to better keep the halos in check. Taken with a RedCat 51 + ASI1600 using Baader RGB and Astronomik NB filters - all unguided. Pre-processed in APP and then processed in PI and Affinity. As always C&C welcome. Thanks for looking. Adrian

Great iamge Graham. The Samyang is a joy to use and produces quite extraordinary results. I certainly won't be parting with mine! Like you I just wish we got more opportunity to use it! Adrian

Really like the sense of depth you've achieved and love the colours - excellent job! Adrian

Very nice image - and nicely processed. May I suggest you post the jpg or maybe png so it shows up on the thread and members don't have to download 170MB file and open a viewer, that way you're likely to get more feedback. Thanks for sharing. Adrian