Going H-alpha: PST dismantling 1. Prism removal.

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WARNING: SOLAR OBSERVATION REQUIRES GREAT CARE AND SAFE FILTRATION.
INSTANT PERMANENT BLINDNESS CAN EASILY RESULT FROM SIMPLE MISTAKES.
NEVER LOOK AT THE SUN THROUGH ANY LENS, MIRROR OR INSTRUMENT UNLESS IT HAS BEEN FULLY TESTED AND APPROVED FOR SUCH USE. YOU FOLLOW MY EXAMPLE ENTIRELY AT YOUR OWN PERIL!


I will post some images of the focuser mechanism parts tomorrow to aid prism removal. This is a vital step if you are serious about dismantling your PST!

Removing the prism allowed me to slip a small mirror in at 45° to photograph the ITF, UV/IR filter 'head-on,' with flash. It looks awful in the image though the reflective outer surface is actually flawless and nicely blue coated. So I'm not quite sure where the 'orange peel' is actually situated. Presumably on the back side of the ITF, UV/IR blocking filter? Another filter, in the form of a square block lies under the UV/IR filter.

Further online research for PST and rust resulted in more information. The rust appears between the filters as a result of moisture and/or heat stress. Meade offered a replacement for the rusty objectives and repaired other filter problems under guarantee but the long term reliability of the PST remains in doubt. Repairs outside the guarantee period are reported to be very slow and costly.

I still need to remove the eyepiece holder to unscrew the ITF, UV/IR filter's locking ring. A large DIY outlet in the city has the 'Boa" type strap wrenches I need. I'd order a pair online but need to visit another outlet nearby which has 2mm screw extractors in their cased, multiple sets. Which I am very unlikely ever to use again. I already have a set but of five but the smallest is much too big.  Unfortunately this second chain doesn't offer online sales. So a 50 mile journey seems likely. Though I could postpone the screw extractors until later. Dismantling the PST takes greater precedence if I am to progress.

Click on any image for an enlargement.

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