Adreneline

I imaged IC1805 in late November 2022 using a RedCat 51 and 6 nm Astronomik 1.25" filters.

I have since been entrusted with a SharpStar 13028HNT f2.8 astrograph from a fellow SGL'er so I revisited IC1805 with a 2" Astronomik Ha filter and combined the new Ha data with the previous OIII and SII data.

For whatever reason (still to be determined) PI refused all attempts to register the SS and RedCat data; in the end I managed to get APP to register everything with the Ha as the reference, and this is the end result.

Post-processing in PI.

Thanks for looking.

Adrian

"A short stack of subs" or not this is a great end result and definitely worth sharing. Just goes to show what can be done with minimal data and careful and considerate processing.

NGC2158 steals the show for me.

Adrian

That is an outstanding image Adam. Great subtlety of processing has revealed an intriguing object in perfect balance with the background star field. Star shapes and colours are excellent across the whole field of view - your twin scopes are doing an amazing job. As you’ve rightly pointed out, patience is the name of the game in AP! Glad to hear you’ve crossed the rubicon with PI too - patience and persistence pays off in every aspect and it shows in this fantastic image. Thanks for sharing. Adrian

22 minutes ago, Magnum said:

woooh bit surprised  by this comment, as I haven't name called anyone

I'm afraid that "designed by monkeys" and "... PixInsight ... a barbaric environment of tyrants fresh from the Spanish Inquisition" don't amount to compliments in my book.

18 minutes ago, teoria_del_big_bang said:

Agree 🙂 

I have now used BlurX on a number of my images and have been impressed by the early results, all the more so since using PSFImage (a PI script) to obtain a value for the PSF.

As with all these processes and scripts it is taking care to ensure you are not taking more from the data/hardware combination than it has to give.

Adrian

I'm really not sure @ollypenrice and @Magnum that that all these insinuations and name calling are helpful, and I speak as someone who has been banned from the PI forum for comparing one script within PI with APP. I am disappointed, but not surprised, a Moderator has not stepped in and made comment. You may be employing the use of emojis to imply jokes but the jokes are in poor taste.

As for cost comparisons in my case PI represents less that 5% of my total outlay and in my opinion that small cost has been recouped many times over.

This is a hobby and as such to be enjoyed because it enriches our lives. If you cannot rise above the differences and use PI, PS or whatever you care for to your own benefit and hence the benefit of all without resorting to name calling and insults then perhaps you should find another hobby.

Keep this thread on the subject of BlurX and not a debate about PI vs. PS.

Adrian

I had the same problem. I use a 24W heating pad (for cats) strapped to the mount before placing the cover; it’s on for 2 hours and then off for 2 hours. The mount stays dry  - no sign of moisture or condensation. 

On 25/12/2022 at 18:33, geeklee said:

Great use of the data to create an image with depth, detail and subtle colours.  The dark dust/globules look fantastic too.  Hard to imagine many better IC1396 versions at this focal length.

Thanks Lee for your very generous comments but above all thanks for the data and thanks for the invaluable critique whilst I arrived at the final image. What you see is in no small part due to you.

On 25/12/2022 at 18:47, Mr Spock said:

I like the processing on this one - very delicate. It reveals far more detail than some of the over processed images you see. Very nicely done 👍

Thank you Michael. I am always concerned about overstretching the data but also aware that many prefer the more saturated approach to processing - I am not one of them.

On 25/12/2022 at 19:21, tooth_dr said:

Lovely version Adrian, the starless version is really something

And a sensible idea combining your data.  More to come hopefully from you both?

Thank you Adam. Really clear nights - with minimal/no Moon - are so few in the UK and getting sufficient data to complete an image can be very frustrating. Because my equipment and Lee's have so much in common it makes sense to share, otherwise you can end up with insufficient data to get anything at the end of the season.

On 25/12/2022 at 19:26, Sunshine said:

This is stunning! I don't think i'll ever make up my mind about starry vs starless. 

Thank you @Sunshine - I agree it is a tough one. I tend to feel that if I am imaging a nebula then that is what I want to see as clearly as possible and in my opinion that is best achieved with the stars removed. I recognise many, maybe even most, like to see the stars in the image so I've done both and processed the stars as carefully as I can, but not at the expense of the IC1396 and other nebula in the image.

Thank you to one and all for your comments.

Adrian

6 hours ago, dark knight said:

 

This is another collaborative image with @geeklee

This is my first image with my new 3nm Antlia NB filters - Ha and OIII so far - and was going to be a HOO image.

Lee offered me some of his data taken with his RedCat51 + ASI294MM and in particular some SII data to allow me to put together a SHO image - my preferred option.

This is 33x300s 3nm Ha + 25x300s 3nm OIII from my RedCat51+ASI1600MM, and, 26x300s 3.5nmHa + 24x300s 4nm OIII + 24x300s 4nm SII from Lee's RedCat51+ASI294MM.

In total the above equates to 11 hours of data.

Calibrated, registered and integrated in APP and post-processed in PI.

This was processed as starless and stars separately before combining in PixelMath.

The normal processing in PI using NoiseX and StarX along with the usual PI processes.

BlurX was also applied in the linear stage using the PSFImage script in PI to set the PSF value in BlurX.

I know it is customary to have the trunk at the bottom but I quite like to see the dancing dervish down there.

Thanks to Lee for all his comments and critique in arriving at the finished image.

Thanks for looking.

Adrian & Lee

8 minutes ago, Adreneline said:

There are lots of examples on the Samyang thread, mine included with lots of photos etc. HTH

I found it helps if the spacing is exactly right and you accurately measure the backlash in the gear/pulley system; once the backlash is determined you can set the min and max steps with confidence and ascertain a limit position, all in the software.

NINA did the job perfectly but it's a lot easier with an ASIair.

HTH

44 minutes ago, ollypenrice said:

Hi All,

We are setting up a Samyang 135 with a ZWO focus motor for unattended robotic imaging. Has anyone done this? The problem is that the lens can't be driven a long way past the infinity stop in order to build a vee curve, whereas it can on a telescope. We'd be grateful for any pointers on how to go about this, with what software, etc.

Thanks,

Olly, Paul and Peter.

There are lots of examples on the Samyang thread, mine included with lots of photos etc. HTH

2 hours ago, PeterCPC said:

I stack using APP so I end up with a TIFF. Can that then be used in PI with BlurX?

Why not set APP to save as .fit and retain the header information which PI uses? I didn't think linear tif files retained the .fit header but please tell me if I am wrong.

21 minutes ago, wimvb said:

So far, not even Russell Croman can beat the advantage that a dark site offers.

Don't bank on it. AI rules.

This has been a really interesting and at times exciting thread to read so I thought I would add my two-penny-worth of real experience.

In 2016 I started with a NUC and SGPro/BYEoS - NUC inside, OTA outside with long'ish cables - and an Atik CCD camera.

Then I moved to the NUC to the mount - much better arrangement in terms of cables but not so comfortable to use.

The I moved the NUC back in doors and used very long cables - not good at all - a bad move. At the same time SGPro got updated and became for me more of a pain than a gain. (Sold the Atik(s) and bought my first ZWO cmos camera).

Then I put the NUC back at the mount and bought a cheap reconditioned laptop and used Windows Remote - that worked pretty well most of the time. It is a fact that Windows can be a bit tricky at times - full of surprises when they are least needed.

Then I bought a RPi3B+ and installed Ekos/Kstars and all that other stuff. I tried and tried and tried again - and every time/night there was a problem which ranged from trivial to show-stopping, like driving the mount into the tripod.

Then I bought an ASIair Original - very good.

Then I bought an ASIair Pro - very, very good. Wifi a bit disappointing but there are work-arounds - like a cable for me.

Then I bought a MeLE Mini-PC - see below.

Then I bought an ASIair Plus - exactly what I expected.

Guess what, I hardly ever use an PC and when I do it's to get my fix of using BYEoS - which I love, love, love!

Based on a recommendation I bought the MeLE and installed NINA - so much to like and so much to frustrate - too many hours lost to solving problems rather than imaging. All the problems may well have been of my own making (like trying that Green Swamp thing - what was I thinking?!).

For me, in the evening of my life, I absolutely love the ASIair. 99% of the time it is stressless, reliable and as easy as the proverbial 1, 2, 3. I can be fully set up and imaging in 15 minutes. Platesolving 100% reliable. Meridian flip - go to bed and let it happen. Setting up guiding a breeze. PA a bit fiddly (maybe my mount)  but works just fine. Storage - okay it's not good on the Original, loads better on the Pro and 'problem solved' on the Plus.

I have sold my soul to ZWO and I am in no way ashamed of that fact, and neither should anyone else be - ashamed of me  

As for the argument that the ASIair can only be used with ZWO products (excluding mounts and two dslr brands), so what?

If you haven't tried it don't knock it. I haven't tried so many things in my life and I 'knock' myself for not having done so - except wingsuit gliding.

Do whatever works for you and don't forget to enjoy! It's a hobby.

32 minutes ago, paul mc c said:

As we all know...frosty night means clear skies

🎶"It ain't necessarily so"🎶

... least not here! 🤣

Good luck if it's clear for you though 👍

Very nice Göran. Love the colours and depth you've managed to achieve - very sympathetic processing. Adrian

19 minutes ago, StevieDvd said:

What's the software used in your post that produced the magic?

Hello Steve. No magic I'm afraid 🙂 - and nothing "embarrassing" about your image. (you want to see some my early attempts 🤪)

I used AstroPixelProcessor to remove the background gradient(s); APP is also my software of choice for all pre-processing.

I used PixInsight to process the image. It has a reputation for being user unfriendly but in my opinion it is no different to PS - you have to get used to it and the way it works and does things.

I am very much of the view that PI is worth every (one off) penny and represents a small percentage of what I've spent on hardware over the years; it lets me get everything there is to get from my hard earned data.

PS is part of Adobe's Creative Suite - PI is anything but "creative". Okay - I lit the blue touch paper! 🤣

Hi Steve.

I've had a very quick go at the .fit file and once the background gradient is removed and a little tweak with colour calibration quite a lot more detail is revealed and a nicely aligned histogram.

I am not at all familiar with the 585 but generally I would say stick to one gain setting and vary the exposure.

M42 is a very bright target and I've used exposures as short as 15s in the past; 180s and above would seem excessive to me.

I've not used ASIStudio so cannot offer any advice on that one, but I do use an ASIair and love it!

HTH

Adrian

Two at once on a freezing cold night - must be mad!

43 minutes ago, barbulo said:

Where should they be placed? Any example would be more than wellcome.

They screw on as would any end of lens filter.

I bought one of a well known online supplier!

44 minutes ago, barbulo said:

Is it a good idea to 3D print them?

The thread might be a bit tricky and you really need a very clean edge on the inner diameter.

HTH

5 hours ago, powerlord said:

It sounds like I'm mistaken and most camera lenses are not petzal types then ? That does, I have to say tie in with my test tonight, when I found massive what looked like coma around the sharp centre when I tried it.. though as I've seen this before using my only L-extreme at correct back focus, I assumed it was something to do with fast lens vs filter and decided to image with the redcat tonight instead.

Hi Stu.

The SY135 is a great lens but it a real challenge to set it up with an Astro camera and filters. My thinnest spacer is 0.1 mm and I wish it was 0.05! I’ve even been known to try tissue paper spacers - not recommended! All my experience with this lens tells me achieving focus with the registration mark within the base of the L is essential. It’s also very beneficial to stop the lens down with a step-down-ring - I step down to 49 mm giving an effective aperture of about f2.6 - it really helps with peripheral stars and the reduction in aperture/speed is a small price to pay.

I also have a RedCat and what a joy it is to use. My ASI1600 on the RedCat has a very similar f.o.v. to the ASI183 on the Samyang - a great combination.

Good luck with getting optimal spacing on the SY - the pain is definitely worth the gain.

Adrian

10 hours ago, powerlord said:

However, if you use the shorter adapter ....... then you bring the focal point into the middle of the focus ring range

Forgive me if I am misunderstanding what you've described but to me this seems to be exactly the wrong thing to do.

All camera lenses, but let's just stick with Canon, are designed to work optimally when the spacing is an exact value between the back of the lens and the camera sensor. The front face plate of a Canon dslr camera is an exact and carefully controlled distance in front of the sensor - the end plate of a Canon (fit) lens is specified as an exact distance from the last lens element within the lens. When the lens is fitted to the camera there is an exact optimal distance between the camera sensor and the last element of the lens. When focussed at infinity the registration mark on the lens should be positioned within the base of the 'L', whether the camera is a Canon dslr or a cooled astro camera.  If the spacing between the last lens element and the camera sensor is incorrect the registration mark will be be either before the 'L' or after it. There are countless references on the web to ensuring that at focus the lens registration mark is within the base of the 'L' whether it be a Samyang, a Canon, or whatever the make of lens. That's one reason why we all want to know the exact back focus on an astro camera.

I understand fully your comment about the EAF driving the focus ring into the end-stop (not good for the EAF or the lens) but that is easily fixed on the ASIair by 'reversing' the direction when the EAF first offsets the focus to start to generate the 'V' curve. When I AF my Samyang the EAF moves the focus ring way round to before the 10m mark and then progressively comes back to the 'L' and just slightly beyond; it does not come up against the end stop.

As I know you know spacing is so critical on the Samyang 135. It was equally so on my Canon 200 mm lens although the focus ring on the Canon 200 had like a 'slipping clutch' so that if you attempted to rotate the focus ring beyond the infinity mark it would effectively slip and not come up against a hard stop. Changing the spacing by as little as 0.1 mm can make a significant change to the focus position. Until recently my biggest challenge has been ensuring that I can focus my 1mm thick Astronomik Ha and SII filters 'within the L' whilst achieving a focus position with my 2mm thick Baader OIII that was as close before the 'L' as I could manage. The 1mm difference in thickness requires a change in spacing of 0.33 mm - that is huge for a Samyang 135 lens. If the spacing is incorrect then star shapes are likely to be compromised especially toward the periphery of the image.

Please tell me if I have completely misunderstood your post above and you are indeed still achieving focus with the lens registration mark within the base of the 'L'.  

As an aside the gear ring allowed me to establish accurately the backlash in the system:

Photo dates from when the EAF was above the lens.

19 hours ago, Tomatobro said:

Even with a "slack" belt it works fine. On one of my lenses the tension on the pulled side of the belt pulls the optical train out of alignment so i always instruct the focuser to reverse a couple of stepper motor pulses to centre the optical train and even out the belt tension but I see this only one one of my Samyangs.

For this reason I do not tighten the belt over the lens but just enough to prevent the belt from riding out. Even with level of tension slippage of the belt does not occur. Perhaps one reason for fitting a separate drive pulley close to one end is to apply the offset load of the belt closer to the focus support mechanism.

 

I don't doubt that it works but I do have doubts about using that arrangement based purely on my experience. I found that despite the level of tension in the belt the belt would precess on the focus ring and so I found there were issues with repeatability over time. This problem was exacerbated for me because I was using Astronimik 2" Ha and SII filters and a Baader 2" OIII filter; the Astronomik filters are 1mm thick whereas the Baader is 2mm. This difference in thickness required very different focus positions (~500 on the EAF) and over time the belt would 'walk' around the focus ring so although the relative difference for Ha/SII and OIII remained the same the absolute positions on the EAF changed. In the end I adopted the same approach as @geeklee and installed a toothed ring which works perfectly.

With regard to mounting the EAF @ollypenrice I have tried under, over and at the side. The under-lens mounting I didn't like because it sets the lens high and the guide scope even higher above the Vixen bar and flexing problems start to surface. Mounting the EAF above the lens screws up any chance of mounting the guide scope. In the end I have settled for 'at the side' mounting of the EAF leaving the top bracket clear for the guide scope. The downside with 'at the side' mounting is it throws out the whole issue of DEC balancing which is partially resolved by rotating the EFW but even this requires the addition of a 100g laboratory weight to achieve perfect balance on my CEM25. Rotating the EFW however does allow space to fit the guide scope so it all seems to be a win-win in the end.

I am a 100% fan of using the WO mounting ring and buying the WO handle to mount the guide scope. I also use the ZWO camera support ring to ensure I don't get any misalignment of the camera-lens combination - no droop! Even though I use the Astrojolo M42 replacement end mount for the lens I was still getting a tiny amount of droop - the ZWO support fixes the problem completely and provides a very rigid mounting platform.

All personal experience over the last three years of tinkering and messing around - exactly what you do on cloudy nights!

Adrian

That'll be perfect for Santa spotting!