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I recently got a ZWO 585MC cooled camera, to pair mainly with my Tak TSA 102 f/8 refractor. This gives a better field of view, smaller pixels, and higher quantum efficiency compared to my other camera (a ZWO 071MC Pro). One benefit of the smaller sensor is that I don't need to use a flattener. I managed around two and a half hours last night on M51 and got the result below (from stacking 149 60 second images in DSS and then some further processing using GraXpert, Affinity etc.). An IR/UV filter was used. Although the moon was up, the end result was fairly reasonable, to me. Autoguiding, autofocussing etc. was all managed by an ASIAIR Pro and I used my RST-135 mount.

Looks like a WiFi camera

Me too, but I made an exception 😅.

NINA help needed please Learned people, The night before last I was acquiring images with NINA,OK . My screen layout is to have a narrow camera panel on the left, an image panel in the middle and a narrow sequencer panel on the right. Whist an exposure was in progress I clicked the OPTIONS tab in the left pane. My screen became entirely green with no sub panels. I could not get rid of this screen, but the image capture was unaffected. Last night I started up NINA with the target focused and centred, again the sequence was successfully captured captured despite the green screen.. This afternoon I started up to try again and no green screen and the three panels I wanted were available. The image panel top was low on the screen and the drag up action would only raise t a small way. What do I need to do? Chris

I decided to have a go at the Iris Nebula when the stars appeared briefly last night. I only managed to get 20 minutes of total integration of 10 second subs. It was over the northern part of my garden which is heavily light polluted due to street lamps and Heathrow in the distance so I have previously avoided it. There were also many intermittent cloud bands. I tried several apps for stacking and stretching but the best one for bringing out the blue nebulosity turned out to be Astro Pixel Processor, unfortunately there is no structural detail visible which doesn't really surprise me! I realise this is precisely why I have the Seestar, the forecasts last night showed continual cloud cover, I wouldn't have contemplated setting up my astrophotography kit. If I had set up my longest scope the iris nebula would still have been a tiny blob. Setting up the Seestar took just over 5 minutes.

Hi Chris, Yes this was using the Starfield. Its a great scope. We should probably meet up sometime as we are in the same part of the world! Vaughan

@Giles_B My goodness you've been spoiled my friend! I've only had 3 nights this year! lol I was actually imaging M101 last night with the Moon roughly 40 degrees apart from my target. I have looked at my data yet, although the subs coming through looked sorta ok. I'll have to wait n see later! ( I know, it's probably silly shooting so relatively near to the Moon but I'm hopeful! )

I have everything mounted on a perspex board with screw holes located so I can move it between my newt and frac as needed. I have one USB and one power cable going through the mount, excuse the messy cabling but I was traveling

Oh dear! That was what i already feared ( I was about 90% sure! ) it was! It's junk like that which puts potential long term passionate astro-nuts off the hobby for the rest of their lives...really not good!

This just popped in my FB feed, it is not 1st of April so, it might be legit 😏 A new ASIAIR or something?

Thansk for the suggestions. Michael suggested similar thing, but without the tube I do not see any tracking either, unless the nut is undone more than i thought so it is completely slipping. I will definitely look into getting a a new power supply.

Mission Accomplished. As they say, pictures speak louder than words. This is M3 with a more or less OK alignment. I don't have a proper DSO camera so this was with my cellphone through a 15mm eyepiece on my 8" DOB .. 80x magnification. the Aluminum segments that you find in most plans are definitely not needed. Wood is a lot easier to deal with and lined with a bit of door tightening rubber it runs extremely smooth.. no jerky motions of the objects whatsoever even at 800x. There is some drift at this power, but it is smooth and mostly to not exact alignment/speed setting. I captured all of this on video of the Moon and will be compiling it into a nice 10-15 minute video of how I made the platform from start to finish with the key lessons learned. The price tag is really small for this one, given the performance I am getting. Next time I am doing it with Plywood. When you break it down , there are just few parts: Plywood - about 30$ EQ 2 Motor - 37$ from Aliexpress with shipping Wheels and pre-cut iron rod 0.8mm - 10cm long - about 10-15$ Some spherically curved bolts - 2$ Regular wood screws - 1-2$ optional: Li-Ion rechargeable 9V batteries - about 8$ (which I bought) A hand-held controller for the speed of the motor - they go for about 2$. I will make one as it was very frustrating having the fine tune the speed by going back and forth from the eyepiece to the motor. All in all , a nice price tag of around 80$. A new one (albeit prettier) sells for about 500$ here with the same motor and same performance.. I may make a couple of these for a 12" DOB and sell them for 250$ each. Already two people expressed interest. It is far below my hourly wage when I count the time I need but it is fun and always nice helping out an astro buddy :). The biggest advantage of building one your own is you get to simply make it fit your telescope exactly and you understand how it works. Also you can cut the segments exactly for your needs. By the looks of it, this one should be OK for the 12" as well , which I already have on the way. It provides tracking for about 90 minutes, which is great and so comfortable that I found myself forgetting to reset the telescope after an hour of observation.

The 44mm results with a big coma. Increasing the distance makes the coma smaller. When the spacer is 1.2mm thick, some corners have small coma while others has radial elongated stars. Spacer thicker than the 1.2mm results with elongated stars only.

It is all beautifully encompassed in the book 'Magic Furnace' by Marcus Chown.

Going back to the original report, the worm is turning, which suggests clutch slip. Driving at high speed might overcome some of the slip. A good test is to remove the scope tube and just leave a flag (bit of paper) on the mount and see if it tracks. If all is well on light load, you have a slipping clutch. Skywatcher clutches are not the best in the world. If the clutch is slipping, tighten the nut by a small amount. Say 1/10 turn and see what happens. I would also get rid of the small (uknown origin) plug top PSU. Put a decent supply (like a Nevada) on there and you know you have a good supply. Explaining why an unknown and under-rated PSU is risking problems requires more than a one line answer🙂 HTH, David.

This Spring I’ve been imaging the spectacular Leo Galaxy Cluster, a mere 330 million light-years from Earth. Containing at least 70 major galaxies, the Leo Cluster unusually consists mostly of spiral galaxies, which are best seen here cropped from the original widefield image. The ability for an amateur to image something like the Leo Cluster from my back garden was exciting and very rewarding. Graham Imaged from home in Redhill, Surrey William Optics GT81 + ZWO ASI294mm Pro L x 30 @ 180 sec R x 31 @ 180 sec G x 31 @ 180 sec B x 31 @ 180 sec Total integration: 6h 9min

Many thanks for all your comments and feedback. I have found that I can remove the ring from the flattener (TS 1.0x GPU Superflat 4-element 2" Coma Corrector) and this allows me 3mm less back focus. Kidney beans means to much back focus. I will get a set of "Astrodymium Colour Coded Fine Tuning Spacer Rings for M48 Threads" spacers so I should be able to get the back focus correct and you get more for £1 more than the Astro Essentials. Alacant: I have serviced the focuser and made a huge improvement by cleaning grease off the tube and retensioning the drive part. It stopped the focuser slipping with the weight of the camera etc. I can't remember where all the rubber rings were. I have the "Tommy Nawratil – www.teleskop-austria.com" manual but is doesn't show all the rubber rings. Do you include the rubber rings under the fixing screws in the 7 you mention? I ask this before I take it apart. Cheers Andy

I bought it second hand, and it came with a mains adaptor (12V 0.9A), I assumed from Skywatcher (from manual: 10 to 15 V DC 1Amp), plugged to the mains. But why tracking ok for the past couple of months if it was a power issue?

The title says it all. Curious to know, on same night, same target, have you seen something in the refractor, you couldn't see in the larger reflector. Thanks Mark

Adding to the good advice from @Cosmic Geoff. The rubber buttons are made with a conductive layer to bridge the PCB tracks below. The conductive area can become worn. Not all buttons fail together and a harder press can make them work. Hence Geoff's questions. If it looks like the conductive layer has failed, you can prove, and make a temporary repair, by rubbing a soft pencil on the button pad. Maybe a careful brush from a PCB repair pen (silver loaded conductive paint) might help. I have never tried it on a flexible keyboard application but it does work on PCB tracks. For cleaning I would use Isopropanol intended for electronics cleaning. This is 99% and more pure. The 'over the counter' cleaning agents often contain additives that can mask problems. For example, denatured alcohol (called methylated spirits over here) is in majority ethanol + methanol. However, to stop you being (very unwisely) tempted to drink the stuff, there are dye additives. These can leave deposits. HTH, David.

"I am powering from the mains." But how ? The spec is "11 to 15V @ 2amp." Users are recommending 13.8V @ 5Amp. And it needs to be a Regulated power supply. Michael

Thanks Peter, that makes some sense. I can see this EEVA and AP rabbit hole will take a lot of work to navigate!

Thanks Lee - I have to confess that one is not my image though. I just look and let others with the skills and patience take the pictures 🙂 This one I can credit: Apollo 12 Command Module, 21 November 1969:

1. FF = Field Flattener, FR = Focal Reducer. These require the correct Backfocus, or coma will result . 2. "Askar isn't a lens, but it doesn't behave like a typical refractor." Whatever, interesting that altering Flange Distance while still able to infinity focus does change the coma. 3. So "Too thin spacer - still coma, but smaller". If going thinner improves the coma, then try an even thinner spacer, or no spacer ? Michael

Yes clutch too, sorry. I am powering from the mains. It's a bit odd as it was tracking ok and I stopped to have a break and when i went back it wouldn't. I could try undo the nut and take the wormwheel off and see if the motor still makes the noise.