Captain Scarlet

Thanks. Yes there aren’t many alternatives when it comes to Lunar stacking. I’ve had a couple of very good results with FFT Registration in PI, but when I tried it on a load of quite noisy and hand-held (therefore significantly randomly rotated) eclipse pics it completely failed no matter how hard I tried. Autostakkert the same.

Very nice. May I ask what software you used for the stacking? Cheers, Magnus

Yes as @vlaiv says, this mount comes as standard with a special "2nd scope saddle" which screws and clamps onto the end of the counterweight bar through a hole in its centre. By its nature, clamping onto the small flat end of the bar, it's unlikely naturally to be in parallel plane to the main scope saddle, and in my case it certainly wasn't. It has a pair of adjusters for one axis, up/down, but not for the other (left/right). I've read of others on here who've complained about the same problem. BTW the manual advises not to use both counterweights and a 2nd scope, which obviously I've chosen to ignore here. M

I had a similar experience. Having got it rather easily through my refractor via goto, and having a very good RDF spot on (literally!) I thought it should be easy through my 15x56 Zeiss bins. Not so - I couldn’t see the pair through the bins and I knew I was looking at the right place. Weird.

A quick session for me last night to try out my new pier extension and to see if I could find this. Luckily my goto went straight to it, unmistakable, never seen Neptune before so v happy. Best for me at 108x through my 105, definite bluish colour and nice contrast to phi aqu. M

My understanding of a sky at, say, 21.3, means that the patch of sky being measured has the same average brightness as if each square arcsecond contained one star of mag 21.3. With only your rods working at that level of brightness, that’s a shade of grey. M

Yes quite. I do however hanker after a Fell Bubble Level mainly because it’s a thing of beauty and engineering excellence.

Although what Cornelius Varley says is right, if you’re like me you’re Irritated by supposed “instruments” being completely unfit for their one purpose in life. All the _bubble_ levels I have, including the one in my very expensive Berlebach Planet tripod, are miles out. Even most of my small rule levels I’ve had to throw out, being up to 0.8 degrees wrong. These things have but one job to do! So I’ve resorted to paying a little bit up, £30 ish for a 6-8” one is about right, and getting ones that are accurate and survive being dropped. Stabila is good. It’s not going to make much difference to my observing, alignment software can easily cope and allow for it, but it makes me feel better... Cheers, Magnus

Home Position and Polar Alignment position are two totally separate things: Polar Alignment position involves rotating the bar until 0 is at the top in the reticule and 6 is at the bottom. You then adjust the alt az adjusters to get Polaris or Octans into the required position. Home Position is where the scope sits on top, pointing towards the celestial pole, and the counterweight bar points directly down. You achieve that by using a spirit level on the bar so that it's horizontal, then using the scale to rotate it exactly 90 degrees. Once you've set them both to the accuracy you desire, it's worth marking them with, say, coloured tape. Cheers, M

There are 2 main types of mount, AZ and EQ. For a beginner, AZ is the most intuitive, it’s what terrestrial photographers call “pan/tilt” - you rotate side to side and up and down to point. To track things in the sky as the earth rotates, both axes need to be changing: a bit sideways and a bit up or down. The other sort is EQ, which can be imagined as the same as AZ, except the whole thing is tilted so the side-to-side axis is tilted towards the North or South pole. This means that once you’ve pointed the scope at a celestial object, only the (tilted) side-to-side axis needs to be moving to match the earth’s rotation. The other one stays locked. There are other considerations (eg “field rotation”) but they only really affect things if you’re talking very long-exposure photos. The process of pointing the axis towards the pole is called “polar alignment”. Your mount is an AZ mount, which the goto controller recognizes, and which means it doesn’t offer it as an option since it’s not relevant. OK more than 50 words but I did my best.

The Gagarin one fits the bill length-wise, but tonight I’ve gone for Cassini

... my wife is away until Sunday, what Astro/NASA/TelescopeEngineering YouTube should I watch tonight? Or future nights? suggestions please...

... in the meantime this arrived today. 16” extension pier to go between my Uni tripod and eq3-5m and/or skytee2. It weighs nearly 6kg!

... precisely this is currently top of my shopping list. I’m not sure how long I’m going to be able to hold out...

I'm currently in the middle Harold Suiter's Star Testing book, so naturally I'm suddenly an expert

They look like diffraction rings to me...

I fairly regularly mount a dual setup on my AZ-EQ6, for visual use, see the image below. The problem I had was that the secondary saddle when attached doesn't quite point in the same direction as the main one: it has elevation adjustment but bafflingly no side-to-side adjustment. It was very annoying, so I resorted to inserting a heavyish-duty guidescope alt-az mounting in between, which worked but was not cheap. Your Mount may be better engineered in this respect. This: https://www.baader-planetarium.com/en/baader-stronghold-tangent-assembly.html a lovely piece of engineering... Cheers, Magnus

... actually that’s a VERY expensive way of doing it ... you need the flock to be all black

Yes thanks - the seller did actually include these as well, though I didn’t use them this time. The scope isn’t terribly big, an APM with telescopic drawtube, but even so I’ll don them next time just to familiarize M

No sarcasm at all ... I was asking sincerely. These things interest me, as a relative newcomer to this field.

(well, new to me) Over the last few weeks I've acquired a SkyTee2 manual mount, a Baader Skysurfer V RDF, and a 3mm DeLite eyepiece; all of which, after a couple of slightly embarrassing teething troubles, I am very happy with. Recently back from holiday in dark SW Ireland, I went out over the weekend in SW Greater London with my 105 f/6.2 refractor for a very quick session just to see how my new accessories toys worked. I learned - that the SkyTee mount would work best with the main unlock knobs facing you rather than away; - that RDFs work much better when pointed forwards rather than towards you; - what the star-test pattern for a refractor with an erect-image roof prism looks like (a regular series of diffrection-rings with a prominent vertical "fire-break" running straight down through it, from the "crease" of the roof I guess. Also, it creates a pair of diffraction spikes, which on a 'frac confused me to begin with. The mount is brilliant, a huge contrast to the wobbly set-up I had to use in Ireland, i.e. a regular photographic 1/4" tripod-plate holding up a 7kg+ refractor on a light-duty video pan-tilt head. That just about worked, I got Saturn with it but very far from ideal. The SkyTee2 is rock solid with those sorts of loads. The Baader SkySurfer V also I like a lot. However the two dot-position adjusters are covered with screw-on plastic covers, and once removed a small coin is required to actually turn the adjustment knobs for alignment. If they could've put a suitable ridge on the the TOP of those covers, to use the covers themselves to adjust, that would have been ingenious. But a coin works. The tiny pinhole in the front apparently-solid lens-cover, designed to project the Sun's image onto the reticuled rear cover, IS ingenious though. Observation-wise, I had to really look hard to find Hercules' main square naked-eye; I observed a much-diminished M13 (diminished from my views from Ireland); Albireo was as lovely as ever; Double-Double was easily split especially with my new 3mm at 216x; I saw M27 Dumbell just about. A short series of targets, but it was all about getting over the newbie problems with new kit. Cheers, Magnus

On the basis that the vast majority of people who own such mirror-shift Maks will use that knob at some stage and put their mirrors away from optimal, what strategy would you (or anyone else) use to re-acquire the optimal mirror-spacing and "remember" it? The only thing I can think of for a non-optical-professional is to learn what the star-test should look like, and use it at various positions to home in on the ideal. But I suspect that would be beyond most of us... Magnus

haha it wasn’t so long ago I recall wasting entire sessions not finding anything! It teaches you quickly M

Your first few objects exactly matched my own last night at likely the same time from Sw Ireland in my 12”, showing my brother in law some things he’d never seen before: M13, M92, M11, M57, M27 and the two blue/yellow doubles... very nice account Magnus

I really like that. The road sign makes it superb imho. Magnus