tomato

It is starting to look like the compound eye of some giant robotic insect. That Paramount will be earning it's keep.

Funnily enough In the early days I used to enjoy capturing 3 or 4 targets in a single night (I still do with the RASA). OK, they weren’t great but I learnt about Goto and the accuracy of 3 star pointing models/meridian flips etc and the buzz of capturing my own image of all of those iconic targets kept me going through the frustrating times. Also your second attempt on the target is almost guaranteed to be better than your first one, which helps. My piece of advice, at the earliest opportunity, make your set up permanent, even if it’s only a fixed pier in the garden. Trying to decide when to set up under iffy conditions and then tearing down and putting the kit away at 2 in the morning with work next day wasn’t good.

Anybody who knows me via SGL will know I am an imaging nut, but dare I say it when it all runs smoothly I can get a bit bored of staring at multiple laptop screens for hours on end and hence can't see a darn thing when I go outside and look up. I enjoyed a great visual session a few years back albeit from a Bortle 3 location with a 20" Dob, so I am looking for a light weight easy to set up Dobsonian to keep in my warm room shed and use when the imaging rig is running smoothly (I know, it won't get much use then). With my budget I have narrowed it down to an Explore Scientific UL 12" Dob, or possibly a used 14" truss tube if the right one comes up. My home location is Bortle 5 so I think a 12" is the sweet spot between aperture and ease of use, but I could still put it in the car for travel to a darker location. I know the early version of the ES scope had issues but they seemed to have been addressed with the Gen 2, does this look like a sensible way to go? I don't want a Goto scope, I want a change from all of that which comes with the imaging rig. Thanks Steve

I tried a triple rig with 2 x Esprit 150s and the RASA8 on the Mesu, but even that mount has it’s limits. On the subject of telescope arrays, @Tomatobro now has his dome operational with a SW MN190, which happens to have a very similar imaging FOV to the Esprit 150, so look out for some images from the SNSLA, the Shropshire Not So Large Array.🙂

As a machining job it would require some decent sized billets and then there is the set up time and all those hours making all that swarf. It can be done though, see @Davey-T’s post further up this thread. The top end bracing plate was a whole lot simpler to fabricate, just more hassle to adjust.

I must have the JTD version then, the ADM saddle does look more substantial.

It is an ADM adjustable saddle which I will say right away is NOT capable of holding the scope steady, with an Esprit 150 on there, it is right on the limit of what the adjusters can cope with, let alone holding it stable. @Tomatobro beefed up the standard lateral adjusters which helps, especially having both screws on the outside of the saddle. What gives me a fighting chance of keeping them steady is the top bracing plate, again fabricated in the shop. The method is the plate is tightened down onto the tube rings on the RH scope, the holes are drilled oversize on the LH scope and this allows the plate to move as adjustments are made on the saddle. When aligned the nuts are tightened together evenly and very carefully on the LH scope until the assembly is secure. Needless to say, this inevitably causes the scopes to move so it’s an iterative process where you learn how the scopes move as you tighten the plate down, anticipating where the scopes will move. It’s best to set an evening aside for this operation but once tight I can go quite a while before adjustment is required. What usually happens is I will knock a scope in the confines of the dome and then another adjustment session is required.

When setting up a dual rig one challenge is aligning both cameras accurately on the the same point on the sky. The initial alignment is not too bad on a wide field rig as the reference star should at least be in the FOV in both scopes. However on my small galaxy/PN set up with one scope centred the star was nowhere to be seen in the other and after about 90 mins of adjusting the saddle on the other scope there wasn’t even a sign of a flare to help me locate it. Then I had a bit of a Jim Lovell/Apollo 13 moment and thought all I need is a large bright fixed point in space and the moon was still visible above the house. After slewing and centering the master scope on a couple of small craters in the middle of the terminator, sure enough the moon wasn’t even in the FOV on the other, but there was sufficient glare visible to allow me to move it in the right direction. Once the slave scope was pointing at the same two craters, I slewed to a bright star and finished the job. I usually grumble when the moon is up, but it got me out of a hole last night.

I suppose if I kept the same set up and resolved never to change it, I would get it running like a Swiss watch. The trouble is manufacturers and retailers keep dangling new kit in front of me...

Olly, I agree with you 100% on your observations regarding the open ended nature of learning process imaging, and your scientific approach is indeed the way to go, but it does require a degree of discipline. The software GUIs don’t help, with sliders to tweak and an instant visual response on screen. However, I would not agree that the image capture is a closed, finite process, with no room for continuous improvement. Leaving aside the tremendous advances in the equipment, e.g. dual rigs, more accurate mounts, fast astrographs, camera sensitivity there are new techniques, eg dithering, ‘lucky imaging’ auto flats generation, new integrated control packages, that weren’t available until relatively recently. These techniques need to be understood and applied, and problems old and new need to be understood and solutions worked out and put into practice. Even robotic set ups need a tweak every now and then. Contrary to your view, I also think there is a sort of plateau on image processing skills. For sure, there are many imagers, myself included, who aren’t there yet, and indeed may never get there, but for those at that level, they regularly and deservedly get comments like perfect, superb, sublime, the best I have seen, etc, so by definition any improvement from there must be marginal?

Wow, 49 hrs... Respect. LA as an imaging site for capturing IFN, who would have thought it?

Superb Triffid, nice to see high end kit being used to the full.👍 That single 60 sec sub is indeed a sight to behold. Leaving aside, if I may, your considerable processing skills, how much further can the sensor technology take AP I wonder? Steve

Yes, the RASA is delivering some superb images from the Hole Observatory, but I think the sky quality helps an awful lot too. I imaged the squid and bat nebula using the same set up as Goran for the same integration time and only the brighter parts of the squid were visible on my image, nothing like the result that he obtained. However, I’ll give the M81/M82 region a go at some point when the RASA goes back on the mount.

Thanks for this, it helps in explaining how @gorann gets those amazing IFN images. I have a RASA8 and a QHY268c, but alas not the same class of sky, or indeed his dedication to the task.

This is a great thread, I’m really impressed with your work @Xilman, on the Saturnian satellite. I’m very much with you @Paul M, I don’t know if I’ll ever produce images worthy of the kit at my disposal, so I really enjoyed the “go deep” challenges this galaxy season, M87 jet (success) 3C 273 jet (maybe), but I don’t know if I can apply the rigour required for techniques described in this thread. My own challenge for next season will be to attempt a very modest version of the HST deep field image, even though it will obviously consume a large proportion of my available imaging time. It will be fun researching where I am going to point the scopes at...

Hi Steve, That’s a far from feeble Pinwheel. It is a challenging target but there is a lot of detail in there and the galaxy will really come through once the background gradient is fixed. I note you have APP, try using the ‘Remove Light Pollution’ in the Tools section, this should work a treat on the background gradient.

I think the talks have been brilliant, you have covered a wide range of interests and the speakers have been to a consistently high standard. A massive thank you from me for all of the effort you and the team have put in to set this up and maintain the high standard for so many weeks. I think with (hopefully) an end to meeting restrictions and increased socialising generally the attendance will drop off so it might be prudent to reduce the frequency. No doubt you have the numbers on the most popular talks, but I have really enjoyed the talks by SGL members and the image processing experts, including the software representatives. When the dark nights return I would be up for contributing to some live imaging/EEVA sessions but of course I know how hard this will be to set up given the UK weather.

So sorry to hear about the accidental damage, hope it doesn’t take too long to rectify. I know I’m stating the obvious after the event, but the Mesu mount is a serious bit of kit in all respects, I wouldn’t entertain powering mine up unless it was properly secured on either a sturdy tripod, pier or work bench.

After analysis of the quality of the subs in APP there is always a spread, but there always 2 or 3 which are well below par, usually trailed due to scope sag or cloud coming across during the exposure. I discard these but generally stack all the remaining subs unless I have the luxury of 3+ hours of exposures on that channel which needless to say is vary rare.

Great M51, I never tire of looking at images of this wonderful galaxy. I too can usually tell how good the final image is going to be by looking at the first few subs. Of course in the UK conditions can and usually do, adversely change during the course of a single night.

You don’t have to set up a sequence in NINA to capture images. You would use platesolving to sync your mount on the sky and centre the object, but as dark sky time is scarce now I would leave this for another time. Just set the image tab to loop and tick the save option when you are ready to collect subs. As you would with the DSLR use short exposures to centre your object and to focus. Best of luck

Try swapping your 27” Mac for an 8” Mak, I’m sure you will enjoy the night sky way more on the second option for all the reasons so eloquently posted.

Great image, a very sharp edge on galaxy, it will be on my list for next season.

Wish you well with this, you have the perfect advert for it with the IKI imaging competitions!

Thanks Olly, I now understand the point you are making, regarding the signal estimation introduced into the colour channels by way of the de-Bayering process. As you say, it can only strive to be as good as the ‘pure’ RGB collected data, never better. Will it still be acceptable with regards to the quality of the final image? Hopefully when Autumn comes around I can contribute some evidence to the debate.