WolfieGlos

I’ve only had this happen to me once. When I first bought my lenhance filter over a year ago I tested it on the NA nebula with the Evostar 72ed with flattener and a DSLR, and it seemed to happen on bright stars near the edges - see below. I had the clip in filter for a DSLR (which didn’t clip, it just “sat” in so it was able to move around…until I taped it in), so I was under the impression that the filter was moving, it wasn’t square to the sensor and thats what caused the spikes. The below image was 2 hours if I recall and it didn’t happen in the first hour, but as the scope tracked the target it started to occur in the later subs and gradually got more pronounced. It may have also been tilt/backfocus related as you can see below all over the image, but I’ve never had it happen since on any image or sub with the 72ed, and certainly not on my Starfield 102. Looking at yours, you may have some slight tilt/BF issue in the top left? Does it occur if you position Alnitak elsewhere in the frame away from this corner? Hope that helps.

Same ole **** different year it seems!! Our forecast has changed in the last 24 hours. Only yesterday it was predicting most of next week to be clear. Last night, it changed to Monday+Tuesday and then Saturday and Sunday (typical as I'm away on the weekend....). Now, todays forecast? Tuesday and Wednesday, partly Saturday and rain on Sunday. I mean...it's so changeable, I think it'll be putting our heads to the windows every night it "might" be clear 😕

I caught that fireball at 11:50 as well, it streaked for what seemed about 7 or 8 seconds, slowly through the head of Pisces. As you say, an incredible sight.

It was perfect for an hour, then it was a few gaps between clouds…and that was it sadly. I probably jinxed it by making that post 🫣 However, being outside keeping an eye on clouds for a while I saw a few meteors including the brightest meteor I’ve ever seen at 23:50, streaking for about 7 or 8 seconds, slowly through the head of Pisces. I had a huge smile for about 5 minutes afterwards, despite looking at clouds! Fingers crossed the forecast for the next 10 days is as Paul has said.

Our forecast has it clear from 2am tomorrow morning, with hazy conditions up until then…it’s been clear since at least 21:30 when I looked out the window on the off chance 😳 Straight outside, rig set up and getting data. I’m in total shock given the recent run of weather. I hope everyone else has the same 🤞

Really nice image, this one’s on my list but that’s a lot of time to get a result as good as yours with our poor weather! Agreed on the spiral, I can just see it in your image turning up the screen brightness, and in fact Euclid appears to show it in a slightly overexposed view: https://en.wikipedia.org/wiki/IC_342#/media/File:Euclid’s_view_of_spiral_galaxy_IC_342_ESA25170723.jpg

Absolutely tremendous image Olly and co 👏 The colour and depth is superb, and this must be APOD worthy surely. I agree with the Wow emoji sentiments! Ive never noticed before how the cone nebula with its surrounds looks a bit like the head of a flower, with the stem running down to the rosette. I suppose this is the extension you were on about in an earlier post. What’s next, up to the Pleiades or down to the Seagull! You must have enough data for a “northern hemisphere” mosaic by now 🤣

If you're able to move to a different part with a garden or roof access after a while, would it be feasible to put the mount and scope into one of those secure storage centres near to where you're moving to? I've never used one, but it could be worth looking at a few prices to see if it's worth doing (along with anything else personal or otherwise you may want to take with you). Alternatively, if you're on a 4th floor, does it have a balcony you could use your kit from? Obviously you would still need to look at ways of getting it all there. I assume there's no way the airlines would allow it even if you paid for the extra luggage and weight? Another thought, are you be hiring a removal company / man with a van / friend on a roadtrip who could take it over?

Close call, glad all of the kit is OK. Our winds were also much higher than forecast, and it lasted all of an hour and it brought a tree down across the road from us this afternoon. Luckily it just blocked the road but if it had been 3m taller it would have gone through our fence and onto the house. So at least that didn't happen to your shed, or that could have been a lot worse. Luckily for me also....it's removed an obstacle from my southern horizon view 🤣

If I wasn't planning to go to mono later this year then I would be picking one up. I see no reason why it shouldn't work.

Cheers Adam. I did think of shooting at f2.8 for the background, and say f4 for stars to combine them but it would require a lot of faff having to connect a DSLR to stop down the lens - which obviously uses a different connection compared to the 585mc I intend to pair it with. Refocusing would also be a pain - so I’ve ruled this out. Another option would be to pair it with a DSLR in the first place I guess. I like the idea of the FMA 180, I’ve just been looking at it and the FMA135 and they are well priced - much more affordable than a Redcat which I’ve always struggled to justify for the price for a similar FOV and aperture. I’ve just had a quote from Wex for the 200/2.8 and I can get £275 for it in a trade in (or cash) - pretty good considering I paid around about £350 for it. I’ll check a few other places but as a ballpark figure that will basically pay for either of those in the Askar range. Although I’m saving for an astrocam later this year (533mm or 2600mc), I can probably justify this and it seems to be the best option to get a working wide field view.

Thanks for the quick reply Adam. I must admit I don’t see the same collimation issue in the second image that you’re seeing (even zooming right in on the bright star), but I’ll take your word on it. I’ve had the lens for a few years, not long before I started Astro actually, and initially I had read it was a pretty good lens for it, maybe that was just due to low cost and the fast aperture. I might try stopping it down again and seeing if its any better at f4.5 or f5, but at that point it’s speed is basically lost. Would you say it’s worth pursuing using the lens at all? Initially I wanted to use it for the fast aperture but if it’s only usable at slower f stops then I’d probably look to sell it and put the funds towards a redcat 51 or SY135.

I don’t actually know the difference between them, but although it says bias frames, it also works for dark flats which are similar (which you just have to put in the biases folder). You will need either biases or dark flats for flats to work. Dark flats are different to darks though, so not sure if you have the dark flats or not?

Using Siril’s scripts is quite easy. Take all your light frames, and put them into a folder called lights. Repeat for biases, darks and flats (use those folder names), and then use the script called OSC Preprocessing. Done 🙂 Just make sure the 4 folders are all in the same directory and that Siril is pointing to it. For narrowband, if using the lextreme, you can do the same as above but use the OSC Extract Ha and OII script. This will produce two files; one for Ha and one for OIII. You can then, in Siril, use RGB Compositing and assign Ha to R, and OIII to G and B for a HOO image. That’s it, aside from then processing the result. I did manage to find a “cheat” way of getting SII from my lenhance filter, but it’s not technically correct. Here’s a result I got on the heart and soul. I used this guide, it took a few goes but got it in the end, using the luminance noted in the post halfway down with the Eagle Nebula. I don’t know if you can use an SII filter with OSC though? I’d be interested in hearing if you can, but like Elp said, Askar have just released dual Ha/OIII and SII/OIII so that might be the best option, and that would also double your OIII integration which I understand is usually the weaker signal.

Well I finally had a test session under some clear skies two nights ago. What with Christmas I haven’t had any opportunities to try during the day. After setting up my main scope, I then set up my Star Adventurer along with the ASIAIR (which I bought in November…first time to test it as well!) and hooked it up to the 585mc and 200mm f2.8 lens. Sadly by the time I got it all sorted I could see the clouds on the horizon and it didn’t leave me long to try a thorough test before the clouds rolled in. Knowing that f2.8 produced the poor star shapes previously, I decided to go for broke and stopped down the lens with my DSLR to f4, removed the DSLR, attached the lens to the 585mc (with a 2” Astronomik L2 filter - no UV protection on the front this time), and grabbed some test shots. Thanks - here are some shots at f4, one out of focus (both sides of being infocus), one with a bahtinov mask infocus…and again without the mask. All 5s subs on gain 252: What I do notice from the rings when out of focus is that they all look concentric. With the mask on, the lines all go through the middle but I do notice there’s another 4th line near the top? Local to the star only. I don’t know what this is. Finally, the last image without the mask, to my eyes, looks to be in focus - but each star appears to have a bit of a red ring around it? Could this be related to the extra line from the mask? I do seem to recall reading somewhere (I can’t find it now) that the lens focuses the red channel differently to blue/green and it might be best to have it slightly out of focus. The focuser on this lens is extremely sensitive; a movement of a millimetre makes a huge difference so if I can get this working I think I’d be investing in an EAF for this.

All good points, thanks, some which I hadn’t even considered. Especially the filter side, assuming you mean the 1.25” are usable with the 533? I think I’ll make a separate post closer to the time rather than bog down this thread, but I was leaning towards mono and you (and Elp and Ratlet!) may have just pushed me a bit closer…. I have a 585mc and intend to try it for galaxy season, well assuming the clouds do one…

With some clear skies (finally) to cap off the year, it of course was paired with the near Full Moon tonight. Usually I go for star clusters in this situation but I decided against that and managed to add some Ha data to this image, captured just over 2.5 hours with the l'enhance tonight. I've never combined Ha with RGB data previously so this was a new learning curve (thanks @ONIKKINEN for your post which came up on a Google search - used the 50/50 blend with R and Ha 🙂 ) , happy with the result and seem to have achieved a better contrast in the arms this time. Definitely something to explore and practise with going forwards.

I just can’t justify the cost of a 2600mm for APSC format in mono, but also unsure how I feel about a square sensor being a DSLR user. I’m not thinking until much later in 2024 so hopefully you (and everyone else) get some clear skies by then…

I’m thinking about getting an astrocam at last, and I’m thinking of the 533mm pro with all accessories (RGB filters and a filter wheel), but it comes in at a similar price to a 2600mc. I’d be interested in seeing what you make of it when you get some clear skies 🙂

All year I’ve been generally quite happy with my imaging time, appreciating the weather for the UK, but these last few months have been terrible and really trying. Despite this, the last third of this year has incredibly been my most productive time all year….with a caveat as noted below. I’ve totalled up my time as below, split into thirds only because I purchased a new scope at the end of April so I decided to see what usage I’ve had from the new one. These are the usable subs that went into images, so the actual total would be a little higher with scrapage. This also doesn’t include Milky Way shots (separate tracker running alongside my main rig), or some Lunar and Planetary that I dabbled in - another 4 hours of imaging and a few hours working out how to do it and finding the planet 🤣 1st January - 25th April = 78:30 hours 27th April - 31st August = 84:49 hours 1st September - 29th December = 90:30 hours* * It’s worth noting that since the start of November, I’ve captured 16 hours (13 of which fall in November…), so it’s easy to see that the majority of this falls in September/October - when I did my 54hour mosaic. I purchased an ASIair in the Black Friday sales in November… it still sits unused. I also know I’ve missed sessions due to social occasions or incorrect forecasts throughout the year, but I’ve always set up even if it’s just for a few hours. And incredibly it’s predicted to be clear tonight for 3 or 6 hours depending who you believe, so maybe a last hurrah for 2023 yet to come … with the near full Moon of course 🙄

Thought I'd take another stab at this one, what with the dreadful weather we're all experiencing, and I decided to go with a different colour palette. Red doesn't appear to be popular, so I decided to go for a palette using it and trying to fulfill the brief of getting the most of out all of the data provided. So this is still an SHO mix, however each are assigned to their "true colours" as defined in Siril's RGB Compositing tool. I also decided to go for less contrast to let the Ha in the darker areas be part of the show while letting the stars - although reduced - try to shine through too. Processing details as below, mostly edited in Siril (including noise reduction) and final polishing and combination in GIMP. SIRIL: RGB Compositing: SHO, assigned to "true colours" (671.7nm, 656.28nm, 500.7nm) with Ha for luminance, HSV composition. Run Starnet and open Starless image: Asinh Transformation: (stretch=1000.0, bp=0.00000) Histogram Transf. (mid=0.113, lo=0.011, hi=1.000) Wavelets Transformation (4, 2, 1.5, 1.2, 1.2, 1.1) GHS LINEAR BP: 0.03 GHS pivot: 0.272, amount: 0.77, local: 0.78 [0.00 0.68] NL-Bayes denoise (mod=1.000, CC enabled) OPEN IN GIMP, s-curve to red channel. Colour temperature tweak. Open Stars-only image in Siril: Negative Transformation SCNR (type=average neutral, amount=1.00, preserve=true) Negative Transformation GHS SAT pivot: 0.000, amount: 0.90, local: 0.00 [0.00 1.00] Export Stars to GIMP, overlay onto starless Screen Mode 100%. Curves to stars to reduce. Sharpening to stars using GIMP defaults. Duplicate stars-only image, and using GIMP Astronomy Plugin (Georg Hennig: http://www.hennigbuam.de/georg/gimp.html ), use filter for Round Stars to change angles in left corner. Black mask, and brush in. Repeat for the other 3 corners. Once again, thank you for providing the data and good luck to the judges in choosing the winners from the superb entries to date.

Great image Wim! Zooming in and looking around you can see loads of those smaller galaxies, and I dare say you could make something similar to a Hubble deep field if you poured the hours in? I had the same problem last night with a social event, fortunately it clouded over when we left at 7 and cleared up not long after after we got back 🤣. Shame it didn't stay clear like it was predicted to.

Looks rather ghostly to me. That's a small galaxy to go for, but that's a great result.

Special? Yeah.....because everything else you guys do is rubbish 🤣 Those large mosaics of Orion and the Milky way you did were stunning. Cracking image, is this in broadband or is there any Ha in it?

Wow, really nice image! Particularly like the blue reflection nebulae - the third one up from bottom (NGC 2172?) looks like a nice target in it's own right.