AbsolutelyN

This is a widefield view of Monoceros focused on the Christmas Tree and Rosette Nebula area. Just over 16 hours integration time with a ZWO 2600MC, NBZ filter and Sigma 105mm Art lens. Taken 16th & 17th Jan 2024. 

Fantastic, would love to have go at solar imaging with a 12" newt! I built two filters for mine, one of them stops the aperture down to 200mm and that's the one I've had most success with - makes for an f/6 200mm newt.  I find persistence, collimation and focusing are key, I get mush at all times of day (99.99% of the day) but persist long enough and you can chance upon a brief moment of clarity - that's all you need - a fraction of a second of good seeing (and patience to process all the data). Good luck, look forward to seeing more. 

This is an image of both AR3323 and 2231 captured this afternoon (5th June) at about 2pm. Seeing was occasionally quite reasonable which allowed quite a bit of of surface detail to be captured. Taken with my Quattro Newtonian, Baader solar film, a continuum filter and a ZWO 183MM.  Stacked in Autostakkert and colourized in Photoshop.   

Another quick sunspot group and again seeing not great ... eventually got some detail in a brief moment of steadiness.  

Finally got the scope out for the first time since February and managed a very quick solar session. Not great seeing but managed this of AR3310 with a ZWO183MM and continuum filter. 

And finally the AR3311/13/14 group

Thanks - I get a bit paranoid of crushing and over saturating the reds. 

Being my first image in a while and the recent extended clear skies I decided to go deep on the Spaghetti Nebula. This is about 27 hours with a 10" Quattro and 2600MM - 13 hours each for HA/OIII and a little for the RGB stars. Must admit that I found it quite difficult to process but hopefully its come out reasonably ok. 

https://www.astrobin.com/1d450e/B/ - HA/OIII
https://www.astrobin.com/a76bie/ - HA only/starless

Detail of structure better seen in the starless HA 

As said elsewhere this is a fantastic image Adrian, really well done and processed. Heading towards being a reflector convert?  

I use a heated pet blanket - you can get them 12v so can plug into scope power supply. They don't get too hot, are waterproof and not too expensive.  

LDN 1251 in Cepheus. Taken with a 250mm Newtonian and ZWO 2600MC - 364 x 120 sec  ~12 hours over  two nights (Sept 26th and 28th). 

19 hours ago, CraigT82 said:

Thanks Tristan, I doubt in another league TBH your Mars images from 2020 were pretty awesome not to mention your deep sky and solar work with the 250PDS! Just lucky I had decent seeing really and was able to get out there, that's half the battle with planetary just being in the right place at the right time

I've not really done any planetary since so quite rusty and was using a quattro so less focal length.  This is the best I could manage but I could only get this level of detail in the red channel and seeing deteriorated fast after this. Just ordered a ADC which might hopefully help out a bit. Are you using WInJupos to de-rotate? That's an area I've never looked into.

Fantastic image Craig, inspirational. Had a quick go last night myself as seeing was very good about 22:30 but then I had to go out and by time got back had deteriorated. Got my best Jupiter yet but this is on another level. Well done. 

Quick solar image taken about 10am this morning of AR3038, not the most steady atmosphere for imaging. 250 Quattro and ZWO 183MM plus 3x barlow. 

I've bought replacement fans direct from them. I had no issues buying direct but on a camera I'd be very careful to work out import costs or you might get a nasty surprise. Personally I'd get one within the UK. For instance I recently had an issue with my 2600MC - sent it back to FLO and they deal with ZWO for warranty etc and just sent me a new camera hassle free.  

I have a 4k security camera pointing at where I setup, recording any movement 24/7. You can access it via phone so easy to check what's' going on from anywhere and setup detection alarms etc. Useful to check meridian flips etc never mind the obvious security implications. 

That's great thanks, I shall have have a go as you describe. 

The stop ring doesn't seem to be detachable at all, seems to be part of the same mould. If I'd known that I'd have gone with the GPU. I did a quick search to see if it was removable and by chance came across this thread: https://www.cloudynights.com/topic/744140-coma-corrector-for-the-skywatcher-quattro/

That has cast slight doubt as to if it is the Skywatcher f/4 Aplanatic Super Coma Corrector or if they have slightly changed it. That might explain why 55mm is not spot on for f/4. Unlikely hopefully. Mine is exactly as pictured here - comma corrector used on reflectors - f4/5

6 minutes ago, Dan_Paris said:

I am not saying that this is the issue that you have, but a star test cannot detect whether the focal plane is tilted w.r.t. the sensor plane. It only asserts that the optical axis and the mechanical axis of the focuser intersect at the focus position. It does not tell whether they are coincident.  For that you need a well-collimated laser, or a Catseye autocollimator.

 

The Steeltrack focuser is a reliable model, but how is the corrector attached to it ? Compression ring, clicklock or threaded connection ?

 

Dan

 

 

Good points, understood. The corrector is just attached with compression ring. It's much better than than skywatcher compression ring, and I've done my best to put even pressure on with the three compression screws but I guess tilt could always come in via that connection. There is no thread on the coma corrector so I can't see any way of making it a threaded connection. I've never understood why coma correctors for reflectors are not threaded. I was planning on getting the farpoint autocollimator. 

2 hours ago, Dan_Paris said:

The backfocus requirement of the GPU corrector depends on the focal length (in order to correct field curvature on top of coma). The exact values are as follows:

• F=600mm,  backfocus = 51,66mm
• F=800mm, backfocus = 53,66mm
• F=1000mm, backfocus = 55,0mm
• F=1200mm, backfocus = 54,66mm
• gtom 1500mm, backfocus 54,60mm

So in your case 55mm should be OK.

Did you check the thickness of the ZWO extension tubes with a vernier caliper? I found that the GPU corrector is extremely sensitive to backfocus requirement, it should be dialed with 0,1mm accuracy. I concur with the idea of buying a set of good quality spacers and spend some time to tune the backfocus.

Do you have the stock focuser?  Which tools do you use for collimation?

 

Dan

 

Thanks Dan that is really useful info. Previously I used the coma corrector on my 250PDS and was very happy with the stars. Image below taken with same corrector, exactly the same 55mm spacing but at 1200mm so 200mm longer focal length. 

I've measured the spacers and they come out at 37.49mm (both together - 16.5 + 21) so no issue there. From your table I'm guessing it needs to be about 0.66mm less spacing assuming the corrector was spot on at 1200mm. 

Focuser is a Baader SteelTrack and I've collimated with a new Farpoint laser and cheshire I got specific for the job. I'm confident the collimation is pretty good, star tests look good. I think it will just be a matter of getting a 20mm spacer and then very fine adjustment spacers - and a bit of time consuming trial and error testing.    

Cheers

13 minutes ago, Clarkey said:

That would be my thought. The 55mm spacing should not be taken as gospel - there is always some deviation. I have a collection of small spacers that get regular outings!

Thanks - I'll order some and give that a go. I've never had any coma corrector spacing issues before but that was at f/5 so probably a lot more tolerant than f/4.  

So the spacing seems to be bang on 55mm. No filters anywhere in the optical train.

Perhaps get some M42 extension tubes and switch 21mm for 20mm? I can then possibly tweak with 0.3mm / 0.5mm spacers. 

https://www.firstlightoptics.com/adapters/astro-essentials-t2-m42-extension-tube-set-4mm-5mm-6mm-7mm-8mm-9mm.html

https://www.firstlightoptics.com/adapters/astro-essentials-t2-m42-extension-tube-set-5mm-10mm-15mm-20mm.html

24 minutes ago, ONIKKINEN said:

Looks to me like like spacing needs addressing as stars have this circular elongation thingy going on around the edges. I thought this meant there was too much spacing between the corrector and camera and not the other way around? Cant find a source for that now though so hopefully someone can confirm that, but could also be the other way around.

Brill thanks .... I think you are right. Found this on google which would indeed suggest too far away. Not sure how that's possible though, will go take the camera off and double check the exact spacing. 

27 minutes ago, Astroscot2 said:

Slight elongation on all the stars, could be flexure?. How are you guiding, OAG or guidescope 

Thanks, not thought of that. It's just got a little 50mm guide scope mounted on a dovetail spanning the tube rings. Never tried OAG but the current setup with guide scope has always worked fine with my 250PDS which was longer focal length.   

I'm trying to get nice stars on my Quattro 250 f/4 Newtonian and just wondering if anyone used to collimating an f/4 Newtonian can make any suggestions on what to tweak?
Star test looked ok last night but atmosphere was not not really steady enough to be absolutely certain. Camera is 2600mc so aps-c. Its using the f4 Aplanatic Coma Corrector and spacing with ZWO adapters - 16.5 + 21 + 17.5 of the camera. 

Any pointers appreciated, it would be a lot easier to sort if it didn't get dark quite so late 🙂

As always I'm on the quest for more imaging speed so I've been researching the Quattro scopes and and very tempted with either the 250 or 300 version. One thing that keeps coming up in the mods is to replace the primary mirror springs. However I've not been able to locate any thread that specifically says which springs to upgrade to. Can anyone point me in the right direction? Many thanks   

You don't really need full spectrum mod for astro - here are a few taken with my standard astro modded 6d.  No filters on these.

https://www.astrobin.com/4pa4kj/
https://www.astrobin.com/n4t69f/
https://www.astrobin.com/07eg1m/?nc=&nce=