Adreneline

You must be delighted with this image Jody. Sh2-129 is a really tough target and you’ve done an excellent job of revealing the elusive Squid. Very impressive stars too. Don’t you just love a RedCat + ASI1600 combination. I wouldn’t swap mine for anything. Adrian. 

I have a tripod mounted (portable) CEM25-EC which I have used unguided with Samyang 135 and RedCat 51 with exposure up to 300 s with no problems at all.

I have also used it with an RC 6" unguided up to 180 s, no problems at all, although that is getting well on to the stated weight limit for the mount and needs careful balancing.

I have a pier mounted AZEQ6 where guiding is necessary and I happily work with that, but I love the unguided simplicity of the CEM25-EC and have no regrets with my purchase.

I have tried guiding the CEM25-EC using an ASIair but to no advantage - certainly not up to 300s. A good PA and you are good to go!

An inspiring target Olly - I wish I had the gear to image it but alas not the case.

I'm with @MartinB with this one - the stars are detracting from the beauty of the nebula.

I've seen this before when putting stars back into an image - whether it be StarX or Starnet that was used for removal.

My experience is it is a whole lot easier to take the stars out than to put them back, irrespective of the method used.

I've tried lots of different approaches most of which result in a very two-dimensional image.

I have found the EZ-SoftStretch script in PI useful for processing the star image and even then it needs 'de-stretching' before recombining with ~((~starless)*(~stars)) in PixelMath.

Failing that I resort to multiple, incremental mini-stretches in HistogramStretch. I am sure there are equivalents in PS.

Adrian

3 hours ago, assouptro said:

simply stunning!

Well done Adrian, we have had an unseasonably dry period and your dedication has paid off!

Thanks for sharing 

Bryan

Thank you Bryan. I’ve still got a long way to go but tonight I’ve managed to get to the 40 frame point - my initial target, now modified to 50. I think getting decent low noise OIII is going to be the real challenge. ”Onward and upward” as my dear departed mother used to say.

Adrian

10 hours ago, tomato said:

Fantastic mosaic, I have great respect for both your patience and perseverance to deliver a result like this. 👍

Thank you. I find having a project is the best thing - something to get my teeth into - I'm just hoping I've not bitten off more than I can chew.

Time and a lot of clear nights will tell!

Adrian

20 minutes ago, ollypenrice said:

What a glory!  These projects can be very difficult to pull off but are worth it.

I'm extremely impressed by APP as a mosaic-maker.

Olly

Thank you Olly. If I can get to the full 50 frames the resulting image should look quite good with NGC7822 in the top left, IC1396 in the bottom right and a wealth of amazing structure in-between. I just need another 17 hours of clear skies!

APP is amazing. I use it now for all my pre-processing. It is a game-changer for mosaics. I have found using the light pollution tool and peripheral cropping each pane makes a big difference when it comes to obtaining a seamless end result.

Adrian

30 minutes ago, peter shah said:

it really does demonstrate the where everything is in the region.....lovely shot

Thank you Peter; as you say nothing in Cepheus is in isolation - it's a mega nebula!

Adrian

1 hour ago, geeklee said:

Great update Adrian.  In the UK and this early on in the year (ref dark skies), you've done a superb job to get as much good data as you have already and retaining the patience to chip away at it knowing how worthwhile it'll be at each stage and at the end.

Thanks Lee. It is going to be a long job. I naively thought I might get this done in one season but I think it's going to be two at least. If I end up with 50 hours of Ha I will need twice that in OIII. Using the Samyang might reduce that to 1.5x's but that' still 75 hours and really relying on clear moonless nights - what are they?!!!

1 hour ago, geeklee said:

For anyone imaging a small part of this, it's a great reference image to see that object in the surrounding area and what it might be interacting with.

I love seeing the way it all works and interacts as if one. If only we could fully appreciate the depth in the sky-scape and the real juxtaposition of these structures. I think 3D images may be some way off!

1 hour ago, Mr Spock said:

Fabulous image. I really like the tonal quality - very delicate but smooth.

Thank you Michael for your generous comment. I am really pleased with the way it is coming together so far. I fear adding OIII may spoil it unless it is really good data.

Adrian

The 24th and 29th September provided an unexpected few hours of clear skies, the first usable imaging session since 24th August to progress my mega-mosaic.

My challenge to produce a mosaic of 40 frames will need to expand to 50 frames to ensure I cover all of Sh2-129 and NGC7822.

The image below represents 31 hours of imaging time using the RedCat 51 with ASI1600MM on the AZEQ6 mount, with 20% overlap on every frame.

Each individual frame is treated to a dose of APP's LPC process to remove gradients and then cropped and resampled in PI.

APP then took 3 hours 20 mins to produce the mosaic from 32 x2-resampled frames; the resulting image was 486 Mbytes!

This is a starless version thanks to Starnet2. I tried StarXterminator initially but although the process completed and produced the 'star' image there was no sign of the 'starless' version! After that I used NoiseXterminator followed by EZSS, LHE and HT to reset the black point. Resampled x2 again to make the resulting .jpg file a manageable size.

More careful and diligent processing is required but at this stage I just want to see how it is all coming together hence the minimalist approach with processes/scripts.

Best downloaded and viewed full-screen.

Adrian

P.S. The chances of completing an SHO version this nebula season are pretty slim I think!

I think you've done an amazing job considering this beauty is so low in the sky here in the UK.

A very subjective thing but I don't care for magenta halos around stars (in fact I don't really like magenta in an image although I accept many do). This is my edit with the magenta removed; I know it changes the colour throughout the image but it makes the stars look more natural to me - and the nebula come to that.

SHO_Crop.png.1e2bcf1e2dcc7c78b76a7dd0a57f5937.tif

It's a very personal thing so if you are a fan of magenta ignore everything I've written except the first sentence!

19 hours ago, pipnina said:

I think it would be nice to narrow down a little on what is too widefield for this challenge.

I agree. When does an image become 'widefield'? Is it determined by angular extent, focal length of lens, either, both? Is a mosaic wide field irrespective of focal length and/or angular extent? Challenge aside when do you publish an image in Deep Sky and when should it be in Widefield, Special Events and Comets? I would have thought 50mm and less was wide field but I am probably wrong. We need @MartinB to define "wide field" please.

2 hours ago, mackiedlm said:

I have made a drizzle integration from a stack of ASI 2600mc images. it looks great but the drizzle integration file is 1.2 Gb in size.

Two questions;

1. Is this correct it seems ridiculosly large - have I screwed up somewhere?

2. Assuming it is correct, when and how do you downsample in pixinsight, to make the file a more manageable size but without losing the benefits of the drizzle?

Thanks for any input.

Sorry, can't answer the first question (well I could but I'd be making it up!).

As for downsampling in PI I use this process:

Set the amount you wish to downsample to achieve a manageable file size.

HTH

Adrian

3 hours ago, Philter said:

I am a bit weary about having to permanently modify the bracket just to fit the EAF if I'm honest as once it's done I can't really return it if I'm not happy!

I am very happy with the performance of my EAF units, so much so I have three; other than the bracket design I can't fault them.

16 minutes ago, Philter said:

Sorry for bumping this but I've just ordered a ZWO EAF to be fitted on a BDS like in the first picture and I have a couple of questions. Am I right in thinking that the slot on the mounting bracket is too small for M6 screws and will need will need to be widened in some way? Also, can you remember how long the screws were that you used to fit the EAF to the focuser? Thanks!

Yes, I had to widen the slots by drilling through and a bit of filing as well . I don't recall the size but it was either M5 or M6 - whatever the BDS takes.

I can't remember the length and I won't be able to check until the weekend I'm afraid. I recall they were short as the BDS threaded holes are only shallow.

I have to say I was surprised that ZWO designed a bracket that would not fit one of the most popular third party focusers on the market, especially as their website says it will fit all popular models.

I think my biggest frustration with AP is that nothing is cross compatible - every manufacturer seems to have different ideas on holes spacing, thread types, slot widths - drives me mad! I'm just glad I own a pillar drill 👍

Adrian

A couple of screenshots to show the 24 pane version with stars and annotated. The jpg's are getting pretty big now - over 40 Mbytes.

Adrian

Managed to add another five panes so now at 24 of the 40 intended.

It was an amazingly clear night last night. At 1.30 a.m. Andromeda was just visible with the naked eye and averted vision - a first for me.

Starless because the object of the exercise is to fully appreciate the extent of the nebulosity.

Next time it's clear I'm going to try to ensure I cover all of Sh2-129.

Adrian

5 minutes ago, Paul Holdsworth said:

Absolutely stunning ! 

Thanks Paul - I'm glad you like it. It's looking clear here tonight so I might be lucky and grab a few more frames. 🤞

Adrian

5 hours ago, JeremyS said:

Amazing! 👍🏻

5 hours ago, Mr Spock said:

That is quite spectacular 👍 I can't wait to see the 40 pane version.

4 hours ago, Kon said:

That's really impressive and puts the whole area into perspective.

4 hours ago, AstroNebulee said:

Wow, stunning and looking forward to the 40 panes

3 hours ago, clarkpm4242 said:

Excellent so far!  Glad you're including the full bat/squid 🤣 cheers, Paul.

Thanks for all the kind comments guys.

I'm also looking forward to the full 40 pane version - I just hope I can stay the 100 hour course and I've got enough processing power in the MacBook to assemble the whole 40 panes!

Cepheus is probably my favourite region with a wealth of treasures to image.

Adrian

I decided to have a go at a 'mega-mosaic' of the Cepheus region using my RedCat+ASI1600MM. So far I've done 18 of an intended 40 panes of Ha, but that's a start!

The grand plan is to do all 40 panes in Ha, OIII and SII; each pane to have essentially the same exposure time and each pane to be processed with an identical set of processes. As the mosaic gets bigger I am having to resample the image just to make it a manageable size. This is not an image for pixel-peepers. There are a few artefacts that seem to have crept into the image I suspect from the star removal process.

The primary idea is to stop me wandering aimlessly around looking for a target - I like a good project. I also want to understand the extent of the nebulosity around the Cepheus popular targets. I can't help but feel that so many target images do not show the extent of surrounding nebulosity in an attempt to focus purely on the intended target.

With 18 panes of Ha complete, each one 10x300s, this is the result so far. 

Starless:

Stars:

Annotated:

If I ever get to 40 panes the image will include Ced 214 and NGC 7822 - and all of Sh2-129 (Ooops)

Thanks for looking.

Adrian

There's some interesting experience being shared here which might be helpful - maybe?

Adrian

I quickly setup an ASI120MM with ZWO lens pointing NE, ~70 degrees elevation.

The Moon glow really spoilt things but these were the best nine of over a thousand 5s exposures. Please excuse the quality.

4 minutes ago, Phillyo said:

I'm now wondering if I should go with a mono setup!! Bloody astrophotography always making me want to spend more money lol.

Why wouldn't you want a second SY135+ASI533MM+EFW sitting alongside your SY135+ASI533MC? It's only natural  

Great sense of depth to the image Jody - and I really like the SHO colours. Adrian

1 minute ago, Space Oddities said:

What aperture are you guys using? Step up rings or the built in diaphragm?

I use a 49 mm step-down-ring giving ~f2.6 - I typically get fwhm figures in APP of 1.8 - 2.0.

21 minutes ago, SteveNickolls said:

Perhaps I would be best to see what results I get simply when changing filters before adding a remote controlled focuser?

Good plan! I managed for a while with manual focus and a BM but found it very difficult to perform very small, incremental movements of the focus ring manually - the move to an EAF was definitely very beneficial. I've only recently started to use autofocus with the ASIair (and NINA with the RedCat) - and I still sometimes check with a BM.

I reckon you could probably set the focus at a median point and the results would be perfectly acceptable for all three filters.

Good luck!