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I have been away from this forum from possibly July - I never find a lot of time to do anything these days, same to be able to relax reading and interacting Astronomy forums.
I asked here a few ideas about making a solar scope or modifying whatever I had and I was recommended to also see Solar Chat Forums and I did.
Thanks to solarchatforums I have been able to do something decent and here is what I have done so far - very slowly!
1. I purchased a second hand PST and replaced its ITF with Maier one from the US and it finally had a clear image coming through + moved Etalon screw to third position - all the usual thing everybody does [after I researched it]!
2. used a new SCT screw-on short focuser [used once or twice on a LX200 R Classic] and using Teflon tape I screwed the PST Etalon to the focuser and purchased a 2" adaptor to fit on Etalon.
3. then used a Chinese 2" to 1.25 and modified the 2" side socket taking internal ring off and making 3x 120° threaded holes and 3x nylon thumb screws and used that as an adaptor to fit the original PST eyepiece holder - strangely enough at present this adaptor is also used as a tilter ... until I buy a proper camera tilter
4. then fit the above eyepiece holder into the SCT focuser with 2" to 1.252 adaptor in it and screwed the whole Gold PST tube with Etalon in it and made a BETTER PST - see image
5. I also initially tried a 2.2x DSLR camera Lens magnifier in front of PST and it decently works too - so PST will be fine for full solar disk mainly and without the 0.5 angstrom - not forcibly needed, I am probably around 0.7 as it is!
6. more importantly, I decided to make my own 90mm solar scope using the above bits and pieces.
7. with the help of Solar Chat Forums [great guys with a lot of knowledge, some are professional - i.e. they know the optics mathematical details - which helps] I purchased a cheap Bresser AR90/900
8. the ONLY usable thing there ... is the main tube, a nice and thick tube - the rest is ALL plastic!!!
I dismounted all parts and saw tube shorter ... a bit too much ! - I could have saved ~6cm really as I went with original ideas, but forgot I was using a different telescope from my initial thoughts - silly me!
So, I added a 6cm extension - no problems there to reach the 20cm inward needed for the PST Etalon which has ~20cm FL
9. initially I used a Tuna Fish 100g tin to adapt the SCT focuser onto my AR152 and fit Etalon inside the focuser to get near the 20cm needed- lets call it Quark unit - which it is really!
It worked well, so I decided to add a second focuser to tune the Etalon ... getting back to AR90/900 ...
10. I was trying to avoid overspending, I could not afford to spend too much - then I remembered I had a unused AR102SX which in my mind I guessed ... the focuser should over AR90/900 and it did!
It just fits perfectly - then drilled three holes for the holding screws et-voila'
11. I purchased a second hand 75mn Baader D-ERF and fit it INSIDE the AR90 tube at about 20cm inside from the front air-spaced doublet lenses, as there are the usual internal rings soldered in and just sit on it and I have about 70mm aperture - i.e 70mm width from the D-ERF for photons to get through.
At that ~20cm distance from front lenses the beam is still very large - probably about 60-65mm - there is no heat in between - no need for air-escaping holes
12. when I have the time I will make a solar finder scope and fit it on the tube - not that is really needed - I usually use CDC to get there almost over The Sun [having an almost exact spot on the yard!] - then use my eye without eyepiece and look thourgh the PST eyepiece holder for solar shinging and centre the telescope over The Sun.
Well, it works well after tuning Etalon focuser correctly and then focusing/tuning Etalon etc. - the usual.
See some images - still learning imaging/processing and a lot more to learn about Solar ... a lot!
I will probably need to get a Power-mate 2.5x when I can afford it!
1st mod - without the original black box - it works so much better - better focusing and sharper viewing too.
This is the AR90/900 shorten tube with AR102SX focuser and adaptors to test it normally
This is complete with the Quark Unit on the right side
Since this image there have been some changing - do not use the revelation adaptor any more and added a 6cm 2" extension.
Here are some images:
I've been looking for a cheapo solution to attach the cheap and ubiquitous red-dot finder to my Celestron 20x80 but didn't like the official clip thing that Celestron sells. Bad reviews complaining of it easily snapping, and to me, overpriced.
After much research and counting of pennies, I went for this all steel, no-snap solution, costing a whopping £6.90 (with free shipping). From the top:
1 x 20mm Dovetail to 11mm Rail adapter. £2.69 with free shipping.
1 x Picatinny/Weaver 20mm Rail Base Adapter (used to attach scopes to rifle barrels) . £5.11 with free shipping
1 x bit of thick plastic to act as a shim. Anything will do.
Bit of background info first.
Having problems auto aligning my Meade 8" LX90GPS. Works at home Liverpool, but not at my site in Hadnall. Doesn't do LNT, not level and never finds north, just spins around like a dalek! Thought LNT module was duff or damaged in transport. Tried everything, then noticed my phone was off north too, tried two other phones, none of the three ever showed same north at same time, even after calibration.
Then to my amazement one of the phones suddenly flashed up High Magnetic Anomalies. Moved 20 metres away and ok.
So upshot is that under the ground below where I can view from is either a metal dump or electric cables or some other magnetic force. Can't dig it up, decked over. Can't move further away it's beyond my fence line!!!!!
So now to finders.. Can't get on with the red dot LNT module for alignment, too flimsy and to big a dot and useless for auto align as above.
So want a decent optical finder, to sight and alugn manually so criteria are
About £100 all in. Not straight through back can't contort any more....
So need RA but is RACI really better than just RA for the extra cost.
6x30 is it too small mag, maybe 8x50, 9x50 or look for used 10x60 or is that too big.
Any ideas or what else do I need to consider, some say EPs are fixed, is this ok or not. Looked at DIY, but the mounts are soooooo... expensive too.
Hope this makes sense and look forward to your help.