Stub Mandrel

APS-C works fine with the 130P-DS

Fusion360 has a thread tool that just creates an image of a thread for modelling purposes. In most 3D programs you can create one by drawing the thread profile (a 60 degree equilateral triangle for metric thread) and rotating it to make a thread. You could try here  for tips (have to declare an interest in that web site).

Not sure. Horizontal expansion (try a negative setting is useful for getting sizes spot on)

I've managed T2 threads, you need a good small vertical step and make sure the thread axis is vertical. If its too tight use the Cura facility for compensating for hole size to keep everything else in proportion.

Astronomers should be thankful! I edit a magazine about model engineering. Our articles are photo heavy, which can in some cases means 20-odd photos of a grey bit of metal on grey machines being worked with grey tools gradually getting smaller... fortunately most of our readers are more interested in the process in question than great artistic merit but it does cheer me up when I get submissions with really good and varied photos.

I'm in competition with myself, not anyone else (aside from the light-hearted SGL competitions!) If I see better pics than I get I think how can I get there? If I see someone who is starting out, they are usually doing better than my first attempts, and if I can offer useful advice or encouragement I try to. Getting published, an APOD or AAPOD isn't about being better than other people, it's about achieving a standard, but equipment and experience can and should be taken into account as results achieved with limited gear (for example) can be particularly inspiring for beginners. I like the approach taken at most model engineering competitions, where most of the entries are judged against a standard, not against each other.

There's a surprisingly huge amount of work in producing a professional magazine, even in PDF format - as I am all too aware. It's not a cheap thing to do, so you need to be assured of a sizeable paying readership, plus an assured supply of quality content well in advance of first publication. 🙂

The Maginon 20-60x60 Maginon spotting scope is back in Aldi, but now £25 but with a proper tripod, albeit a bit flimsy it is usable and quite tall, and has to be with £10 on its own. I haven't been able to take a look at anything yet but it certainly seems from other reviews to be a good choice for keeping in the car for random birdwatching or even a cheeky bit of astronomy. Very light so could be hand luggage on holiday. For the price what's not to like.

I have only found this an issue with VERY bright stars like Alnitak and relatively easy to remove with a bit of judicious healing.

I live in the Midlands. Easily defined as the area northerners think is the south of England and southerners think is the north...

What is interesting is how pathetically weak gravity is. I can push myself away from the pull of the entire earth! A tiny magnet can lift a big lump of steel with the whole planet pulling the other way!

Single frame taken about 4 minutes after contact with the ASI 120MC and £70 Lidl telescope! A little bit of denoise and tiny bit of sharpen as well as false colour.

In Photoshop there's a 'healing Brush' which sometimes does a smoother job.

Went over to join about ten stalwarts from the Rosliston Club, hoping to do a bit of outreach, but we only got a handful of the public. A few very brief clear spells let me focus with my ASI120MC on the Bresser (Lidl special!) Decided not to use a barlow due to tricky conditions. We missed first contact as it was clouded out for several minutes so Mercury was well on the disc by the time we first saw/imaged it. Over the next hour, lost of brief appearances. Then a small but tall tree interfered for most of us while we got about 15 minutes of clear! I got a good run of video just after this. Nearly everyone packed up in the face of thick, dark cloud and light rain, but Andy (who had a Daystar) persisted and I swapped over to my C90 Mak and DSLR and eventually skies cleared again. A few folks who had stayed in the hope of a sighting saw good views on my camera and Andy's Daystar and I got some whole-disc pictures. I packed up and spent a good while chatting interspersed with looks at the daystar including seeing my first prominence. Neither Registax nor Autostakkert wanted to stack the images, so I manually stacked the ten best scoring. Unlike 2016 I had flats, which seem to be even more critical for solar than DSOs! Added some synthetic colour:

There's a sort of repeated 'fish scale' pattern at the top of the Starless one, was that the clone stamp? Still, I want a play with this 🙂

Quick and dirty go at your helix, Gradient Exterminator to colour balance, curves to tidy up the background then Noel's space noise reduction action.

Surely a new thermistor is indicated? The controller will just be underpowering the bed if it's getting false readings.

Try Astromedia for small front-silvered mirrors: http://www.astromediashop.co.uk/Components.html 22 x 15.5 for £2.45 + postage.

The top of the T2 hole may need some manual tidying up.

Too many projects, too little time, at least for the present...

True, I haven't used the 10D since getting a 450D; being 12 rather than 14 bits probably loses more signal than debayering gains. Still it might be fun to try.

Cool - I have an old 10D do you think that would work on it?

Arc minutes are what you need for GOTO, arc seconds are 1/60 the size and what you need for guiding. Backlash in DEC shoudl be as small as you can get it, but totally eliminating it isn't as important as it being consistent - if it is reasonably small and consistent PHD2 will be able to work it out empirically and compensate for it.

Yes, a lot of astro cameras have an 'ST4' output that has four signals which operate the four guide directions. @steppenwolf's (Steve Richards) book 'Making Every Photon Count' explains how to modify the switches in a non-goto controller and set this up.

Well you got an excellent pair of images out of it, even if they are upside down 😉