Rusted

I was surprised to discover that FireCap can auto-guide on the sun in H-alpha using the image capture camera. [ZWOASI174MM] With my 6" f/10 PST H-alpha modified telescope, tracking on the sun, on my home made AWR-ASCOM driven mounting, FireCap happily kept the sun quite stationary. Four green arrows in the top right corner of the live image, capture screen, flashed red when short drive corrections were made. Sadly, cloud kept intervening. Causing the image to dim beyond the software's ability to maintain a lock on its anchor. While it obviously preferred the sun's limb [boxed in red] it chose to lock onto clearly visible, surface texture at one point. It follows that it could probably lock onto Mercury for the transit, cloud permitting. Worth knowing? I thought so.

The instructions can only be generalizations. No two set-ups are likely to be exactly the same. Michael [above] has explained it nicely. The camera sensor is inset into the body. The sensor is where the focus of the telescope must fall.

That very same software went bonkers after a restart after lunch. It was grew-some!

Complaints have a habit of [eventually] getting back to "the perp." I instigated automatic, display scale adjustment on a household name planetarium software by "complaining" on an astro forum. There is still a popular imaging software which can't auto adapt to high res. screens. Despite such screens being available for years. It will tell you it recognises such a screen in sub microscopic text but not provide visible adjustment. Not without the help of an electron microscope.

Dome seeing! I'm a martyr to dome seeing. Except when I'm not. My two story, entirely wooden, observatory building is open all around just below observatory floor level. That's a 20cm or 8" wide open slot all the way around. The floor boards are deliberately gapped to provide air circulation. An open, double door, down on the ground floor provides a chimney effect. Heat rises! The dome skirt is deliberately leaky. A rubber skirt hangs down by its own weight and flaps in any breeze. I have a large door to the west which can push the prevailing wind out through the observing slit if need be. The dome and building are plywood covered to be thermally neutral. Low thermal mass and poor thermal absorption. Badly spoilt by green [camouflage] paint! It ought to be highly reflective white! I sit to the north of the pier at my imaging monitor. I wear highly insulating down clothing to slow body heat loss. The open observing slit [beyond the zenith] should carry my body heat straight upwards and away. Hopefully before it reaches the light path of the telescopes usually facing somewhere to the south. Most observatories are built of thermally absorbent materials baking in the sunshine all day long. Patios and buildings are even worse! They absorb the sun's heat and let it go again all night long. So the dome, building, surroundings, mounting and instruments are very likely to be much warmer than [usually falling] ambient. Excess warmth means a bonfire of the vanities of actually daring to own an observatory. Now add extra human bods inside your "toasty warm" observatory. It can only end in tears. 🤣

A good mirror needs high magnification and good seeing to test its true precision. Thermal issues will confuse matters if the blank is cooling or warming. It usually is! Unless, of course, it is thin and made of something expensive & exotic. A Foucault test needs practice, patience AND personal interpretation. While a Ronchi screen in the empty focuser should show straight lines. As will a humble straight edge. I "tested" every telescope I looked though that way. It will tell you something about support and the optical figure at a quick glance. Always assuming it is not cooling or warming. It usually is! Judging any telescope mirror at the eyepiece is not easy without practice and experience. It assumes perfect collimation and proper support for the mirror blank. With larger mirrors the subject of proper support is a steadily advancing science. What works in a Dobsonian altazimuth will probably not work in an equatorial. Is the mirror properly supported in a well thought out, thermally efficient cell? Inevitably high, thermal mass and tight enclosure, without forced ventilation, just won't do. How is the mirror blank supposed to adapt to constantly changing temperature and inclination? Is it being pinched at the edges? Or being bent into a pretzel by gravity? A fine mirror [or lens] must be judged with great care. Professional reputations [and livelihoods] depend upon it. Judge the critic's skills and experience before you judge the mirror. Demanding a Foucault test is not a sign of very much experience at all. IMHO.

Mercury on the limb. 9.5.16 I have images at about minute intervals. 90mm Vixen f/11 Baader solar foil. Handheld digital snap at the eyepiece.

Do you have an umbrella clip on the dewshield?

I wouldn't be too optimistic about avoiding breezes in such a dome. One which opens over a quarter of a hemisphere rather than having a narrow slit. You are, to all and intents and purposes, standing outside. That said, you do have a permanent mounting set up. With rapid opening and instant weatherproofing on demand. Thermal problems are also likely to be much less with such a wide opening. You are also unlikely to step off into the void beyond the terrace. I cannot compare the Pulsar with the Pod because I have owned neither. My own experience is with a 3m, 10' dome which has an eye-level base ring. Despite the relatively narrow observation slit it can still get pretty draughty in there. One always seems to be observing or imaging in the direction of prevailing winds.

Many urethane wheels are available with brakes. Depending on the load and surfaces I doubt they'd move nor the tyres flex noticeably.

Better late than never? I have some considerable experience with mobile telescope mountings to avoid trees and high hedges. I used to have pneumatic tyres on my massive, welded steel pier for my MkIV mounting. These were standard pilot wheels from car trailers with rise and fall jacks. The whole thing used to sway on the air cushion of the tyres. Mobile but absolutely hopeless for a telescope.! So I replaced them with solid foam, "puncture proof" trailer pilot wheels and jacks. It didn't sway any more but the rolling resistance rose dramatically on lawn and gravel. Always have four wheels if you are going for mobility. Three is recipe for disaster with a top heavy load! The slightest undulation on the ground or even a soft spot will risk a very expensive topple! Here's my 7" refractor on pneumatic tyres. Absolutely lethal on our undulating ground!

I was going to suggest trying the low profile ZWO 1.25" nose but you seem to have tried a number of things. Try to confirm whether you need to reach further inwards or outwards. Trying to focus on the limb is useful. I regularly use a 2x WO [William Optics] Barlow nosepiece screwed directly to the 1.25 nose of either of my ZWO cameras. It seems to be quite a useful GPC [Glass Path Corrector.] Better performing than either of my TS binoviewer GPCs. IMHO. I feel your pain on paying for Photoshop. I too have avoided it so far. Not to mention the terrifying learning curve as well. .

Now that is real progress! Here I have used the same free software. [PhotoFiltre7] MS Paint may be able to do this too. I haven't tried it. I simply cropped your image around the sun's disk and resized it to 400pixels. What is the problem with the ZWO178? Will it not reach focus inwards? Or outwards? What was your "workaround?" Have you tried a Barlow?

Be prepared for a really tiny Mercury. It is absolutely minute compared with the sun's disk.

I've done early morning transits and eclipses from the tops of local hills. We have a low hill to our east with trees and hedges on top to make matters worse. So I carried a Bogen video tripod up for my Vixen 90mm f/11 with Baader foil filter. The Vixen was bolted, via its rings and dovetail, to the Bogen quick-change plate. A compact digital camera was held up to the eyepiece. I use a cut down washing detergent bottle top as a tubular guide for the camera's "nose." Not meant to be off-topic. Just showing it is possible to overcome "local difficulties."

Congratulations Vin! Aim for something more like this: See image below: This is your very own image but with lots of gamma reduction in PhotoFiltre7. [Free software.] I also resized the image to 600pixels max dimension for easy SGL display and converted it to Jpeg. Then I just dragged and dropped the Jpeg image into the bottom line of the SGL posting box from my own Pictures folder. Not trying to be clever! Just helpful. I am extremely grateful to the members of SGL for their infinite patience and endless help.

Roman numerals are a problem with everyday fonts. It needs a specific font to differentiate the Roman 1, V, X & M VIII or XV111 just look so wrong without the bars top and bottom. The Danes use milliarder for billion meaning only 1,000,000,000. Millioner is the more conventional million in Gravely Blighted. To make matters more confusing their currency [Danish Kroner] is roughly 1/10 of a £GBP. So what sounds like a great fortune in Danish money is quite modest in £GBP. House prices only seem expensive in Danish Kroner. I million Kroner [£100k] probably wouldn't buy a garage in London.

Which leads to confusion if you have a bilingual keyboard. The Scandinavian keyboard has Æ,Å & Ø as well as all the "normal" letters. The number pad on the right of the Scandinavian keyboard has a full stop which types a comma! This is because I normally use UK English language but set the Keyboard to Danish. This is because I browse and shop in both languages all of the time. The numeral pad full stop only produces a full stop if I change the keyboard to English. Google spelling checker constantly struggles with bilingualism unless I manually change the language setting. Which, for very obvious reasons, I'd much rather not do. Writing and receiving emails merely adds to the spelling checker's problems. I send and receive mails and messages in both languages.

It sounds as if the "Powers that Be" are determined to minimise your CO2 footprint.

I thought it might be. Polycarbonate might be safer. eBay[UK] has stockists for up to 12mm [or more] if you can find anything big enough for that huge bowl!

That is going to make one hell-of-a Christmas pud! Can't see the relevance of the 20mm acrylic though?

They do say patience is a virtue.

No point in looking today. Solid, wall to wall, cloud!

Nor have I until last night. It may be AWR-ASCOM driver specific.

I've just seen a heads-up "in another place" about a rapidly developing spot. Nothing obvious on Gong Ha yet.