Rusted

Spray foam is rigid. Not what you want at all. Soft sponge foam is less vibration conducting over small areas. Make that area large enough and the foam becomes essentially rigid. The pressure per square unit is not high enough to cause deflection. Spiders must like observatories. After a week of cloudy weather mine had webs spanning the depth and breadth of the 10' Ø dome. I almost felt sorry for them when I slewed the telescope and broke all their hard work.

Just for clarity: The prism is not for tuning. It is ONLY for focusing the PST. It is designed to fold the optical path, inside the prism, to make the telescope more compact. Its support and movement mechanism is crude and a well known problem. The "discounted return" issue raises possible existing faults within this PST. Only with the permission of your vendor I would start with the prism. If the prism is badly aligned it could be the culprit for the image asymmetry. Dismantling the PST without their written permission [as proof of agreement] will void any warranty.

Hi Reeny I had a little play with PhotoFiltre7 image handling software. Just extra gamma and contrast. Cropped and Resized to 700 pixels for the forum. You have captured quite a lot of detail. The offset detail/brightness may be a tilting problem somewhere. Or, the etalon misbehaving. If you are using a standard PST it could be the focusing prism. They have a bad reputation for getting out of alignment. Checking this would involve removing the side of the black box.

Thank you! Generous to a fault! Like all solar imagers.

I recognise those clouds! 😱

Since you brought it up: If I was being really pedantic [as is my lifelong burden] I'd suggest the correct term is white light. i.e. Two words. Easily proven by Google's automatic spelling checker as you type whitelight or even Whitelight but not white light.

The ease with which you lifted that huge cage was ample proof of the sophistication of the lightweight materials you are using.

The sky was almost solid overcast for much of the afternoon. I captured a few videos between the clouds. Resized to 600x600.

That's why they call it "lucky imaging!" I hear that rice in a sealed, poly bag with the soggy electronics, is good.

What a beautiful set of images!

Olde English saying: "Don't spoil the ship for [want of] a ha'penny worth of tar." That said, the OP seems to have thoroughly examined the choice of a six pole truss. Professional instruments would normally carry a much heavier secondary mirror & cell. With the addition of heavy and complex instruments mounted thereon.

I think I recognise those clouds...

All I did was reinforce exactly what you had captured yourself. By making the image black and white it removes false colour. Solar imagers often use B&W cameras. So the pretty colours are often added afterwards. I recommend you download the popular and free ImPPG imaging software and have a play with that. It is quite magical how it can reinforce the detail in an image. There are free image handling softwares out there too. For many years my solar [planetary and lunar] "imaging" was done "handheld" with a compact digital camera. I used a Baader Solar Foil filter taped over the end of a cut off detergent bottle for the sun. The filter fitted snugly over the telescope's dewshield. My special "trick" was to find a suitable detergent bottle top. [Or any other tube in plastic] The closed end of the bottle cap was sawn off and smoothed to accept the nose of my extended camera lens loosely. The other end of the short tube I had made fitted snugly over the eyepiece. I wrapped cloth tape around both ends to protect the equipment. All this tube did was to align the camera with the eyepiece. The tube must NOT be a tight fit on the camera lens. Or it might damage it while it is autofocusing as it moves in and out. It helps to turn off auto switch-off or the lens keeps retracting at intervals. You must not rely on the "adapter" tube to support the camera. It is just a guide. I captured sunspots, eclipses and transits with a small refractor. Mounted on a video tripod. With pan and tilt head and my little digital camera. I often had to climb local hills to be able to capture early morning events at dawn. Here is an old post showing some of my captures with my very old, secondhand Vixen. https://stargazerslounge.com/topic/378483-vintage-vixen-sp102m-f10-achromat-purchase/?do=findComment&comment=4108024 Fullerscopes Telescope Mountings: Venus Transit 2012 images!

Thanks Geoff. I owe it all to the slightly improved seeing and the Lunt 60MT etalon. The Lunt etalon's clear aperture is 35mm in diameter compared with the much smaller PST etalon. [20mm?} The Lunt etalon doesn't seem to suffer from the tiny sweet spot of the PST. With the PST etalon I normally needed to use an 800x800 frame size or smaller. Today's image, with the Lunt, is evenly bright across a much larger 1216x1216 frame.

Keep at it! I had a play with your 1st image. The first [below] is just image handling software [PhotoFiltre7] to crop around the sun and make minor adjustments. B&W instead of colour. The second is after ImPPG and then more image handling software to crop. Both images are resized to 600x600 to suit the forum format.

A new weather system has arrived form the SE. Bringing cloud but steadier air. I have increased the frame size to 1216x1216 for a change from 912x912.

Hi, Assume you want to continue imaging solar close-ups [high resolution] in H-alpha with a 3000mm f/l. Your neighbour's Leylandii hedge and skyscraper extension now hide the sun all day long. You must become mobile! You have absolutely NO experience outside of a fixed location. [Observatory] You decide you'll use the car. With or without its trailer. To drive your kit to local hills or even the seaside. Always roadside locations. So no heavy carrying required. Just the setting up each time. How would you start completely from scratch but with your existing 6" f/10 refractor? What mounting would you choose for high magnification, solar imaging with such a long and heavy beast? Can such a mounting self-align, effortlessly, every single time, in completely random locations? GPS? 12V power from the car? Can it track the sun for hours without serious backlash and the need for constant manual guiding on the laptop screen? I could use my vintage Fullerscopes MkIV but it can no more self-align than I can lift it without a chain hoist! 👴 I'd be very grateful for any advice on more suitable, modern mountings based on personal experience with long refractors. Thanks.

Through thin, high cloud and over a felted, shed roof. Delicate light bridges over the umbra of the main spot. [Right] Hard to see.

Hopeless this morning imaging through high cloud. Bit better this afternoon on first capture but the seeing soon went bad.

A later image. Still shaky seeing but more cloud and less wind.

iStar 150/10 + Lunt 60MT etalon. Very shaky seeing and NE gales.

Bi-parting shutters are in your stars. I'd aim for a bigger, secondhand Pulsar. Failing that, aim for a driven altazimuth. Then you can stack all the scopes vertically in line with the slit. Altazimuth on an equatorial platform? As above.

Widen the observation slit and you have to widen the shutters too. Widen the shutters and you have to widen the rails and increase the spacing on the rollers. A wider observation slit does not allow larger telescopes. Not unless you stick a large refractor out of the slit like a silly cartoon.

Just for clarity: Where the focuser can't move any further inwards then you have to remove something from the image train. Not the solar diagonal with blocking filter! A Barlow or GPC may help by pushing the image outwards enough to reach the camera sensor. Sometime an all threaded spacer can replace an existing extension. Or a component with a physical length. By connecting components without adding optical path length. The ZWO cameras have internal threads to allow them to be joined directly to an instrument or component. Without using a normal eyepiece receptacle/clamp or nosepiece. Conversely: When the focuser is fully out and still won't provide sharp focus then you have to add a spacer to the image train. A Barlow or GPC will NOT help. Only make matters much worse. My Lunt 60MT needs an extension to reach outward focus with a ZWO '174 camera. Visually it is fine. The focuser is at full stretch outwards and still not reaching outward focus without additions. So, yet again, there is no coincidence of eyepiece and camera focus.