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TS102 Stage 2 PST Mod

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I've been quiet in the background for the past couple of months. Moving back to Oz and doing some "mandatory" renovations etc.

Just getting/ making the time to get the gear unpacked.

First cab off the rank is the TS102 PST Mod. This 102mm f11 scope is made by Hunming (United Optics), China and sold in the UK as the LYRA. It's a great scope, and perfect for the PST mod (as others have already found)

I machined up an adaptor which just replaces the original Crayford focuser. (There's a dovetail connection on the rear of the OTA - just needs 3 x M4 nylon screws to lock it in place)The 2" PST nosepiece is held securely by 3 x M6 nylon screws. No cutting of the OTA and the adaptor can quickly be removed and replaced with the original focuser for white light observing. Takes all of 10sec!!

I've also machined up a cell to take the SM60 etalon to give double stacking....

Good to be getting back into it.








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I made a DIY wedge from a Surplus Shed prism and found it a great improvement over the Baader Solar film.

I had the opportunity to buy a Baader wedge and have to say it has exceeded expectations!

The contrast and definition is something else...I strongly recommend it to any serious white light solar observer!

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Thanks for the information Ken. I enjoy doing 'white light' solar with my 4" APO frac and binoviewers. I use a glass Orion filter. I have been looking at the 1.25" Lunt Herschel wedge to use with the binoviewers. Have not seen many reviews but I guess it would be an improvement on contrast and definition.

Were you anywhere near the line of eclipse the other day?

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Just a Just a word about focusing on your stage 2 mod, Ken. On my stage 1 mod, I use the black-box focuser. How do you focus, seeing that you've removed the Lyra's focuser?

Is it a simple case of push'n'pull on the eyepiece? This would seem to be a primitive arrangement for someone with your high DIY skills.

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Mark, I saw the 52% partial from Melbourne.

Peter, no more space...we're actually "downsizing", but good "mates rates" ;-)

Merlin, there's no need for a focuser BEFORE the PST etalon. This, after final adjustment, is always in a fixed -200mm postion inside the prime focus. In the train of adapters there's a Borg helical focuser between the etalon and the BF diagonal.

A stage 2 PST mod is the ultimate solution for the PST; great performance and easy to focus, visually and with any camera.

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