New member here, PST woes.

Use this section to discuss "standard" Baader/Coronado/ Lunt SolarView/ Daystar, etc… filters, cameras and scopes. No mods, just questions/ answers and reviews.
Post Reply
Steve Rosenow
The Sun?
The Sun?
Posts: 6
Joined: Tue Mar 06, 2018 8:04 am

New member here, PST woes.

Post by Steve Rosenow »

Hi, all.

I'm a newbie here, although with regards to astronomy I'd have to say I've been around a bit. Always willing to learn new tricks and I'm just now learning the ropes of hydrogen alpha solar telescope imaging and observing. Let's say I'm pretty hooked now!

Just recently, I acquired a Meade/Coronado PST from an individual an hour away. It was a local Craigslist find and the original owner had only used it twice. Once was during the eclipse last August, and the other was a couple weeks afterward. From there, it sat in a closet, until I picked it up two weeks ago. It was purchased weeks before the eclipse, and fundamentally is a brand new scope.

First glimpse through it was full of nice, contrasty views. A few days ago, however, it suffered an accident. I had it out on a tripod observing and doing a bit of DSLR imaging with it, and got the 'call of nature' so I rushed back inside for a few seconds. While inside, one of the tripod leg lock levers suffered a fatigue-induced failure which brought the PST itself to the ground. The impact tore the internal etalon out of the threaded mounting on the pentaprism body, and misaligned the pentaprism itself.

The etalon is fine, and was not 'decontacted' or thrown out of alignment as there is no ghosting of solar images present. In fact, the threads were relatively unscathed in the impact and the etalon threads into the PST body without issue. However, there was a noticeable loss in contrast (which I suspect is due to the pentaprism being misaligned), following the impact. Areas of plage and solar filaments aren't as contrasty as they were when I had my first glimpse.

When I tried removing the top cover to access the pentaprism, three of the six hex-head screws that hold the cover in place, had stripped out. Incidentally, it was while using a set of brand new Allen-head wrenches that I bought specifically for the PST. I have tried everything to remove those three screws to access the prism to no avail, including the rubber band method, using extractor bits which made it worse.

What say ye, to helping me fix this? And what suggestions might prevail, to give me the contrast I had?

DSC_2879.jpg
DSC_2879.jpg (369.05 KiB) Viewed 5830 times
DSC_2877.jpg
DSC_2877.jpg (291.69 KiB) Viewed 5830 times
DSC_2874.jpg
DSC_2874.jpg (359.54 KiB) Viewed 5830 times


Current and Former Equipment Roster:

8-inch Meade LX5/2080 (Retired; Sold January 2015)
10-inch Meade 2120/LX-6 f6.3 Premiere Edition. (Retired; Fork Mount Sold July 2014)
10-inch Meade LX200 Classic f/6.3 Wide Field
Coronado PST
Meade DS2090 OTA (Reserve status May, 2017)
Meade 80mm Series 5000 ED Apochromat (On loan, May 2017)
Meade ETX-70
Nikon D5100 (#1; Decommissioned March 2016 | #2 Purchased February 2017)
Nikon D5500


Software:
Autostakkert!2 / Autostakkert!3
Registax 6
Deep Sky Stacker 3.3.4
Adobe Photoshop CS6
Adobe Lightroom 6.1
User avatar
solarchat
Site Admin
Site Admin
Posts: 4355
Joined: Sat Feb 01, 2014 3:10 pm
Location: Atlanta, GA USA
Has thanked: 83 times
Been thanked: 1304 times
Contact:

Re: New member here, PST woes.

Post by solarchat »

Well, I’m sorry to hear that. I think every seasoned solar astronomer here has dropped and destroyed at least one scope.
It looks like you already have access to the penta prism in the photo of the unscrewed blocking filter assembly.

P.S. not to be the bearer of bad news but that is the most rusted blocking filter I have ever seen...and I’ve seen a few.

You can just push the penta prism around from that hole as it is not secured with anything except pressure.
I suspect that most of your problem is coming from that rusted blocking filter.
Im not sure about when you said “the etalon screwed into the PST body fine”. The etalon is at the base of the gold OTA where the rubber ring is. The pic you posted shows the rusted blocking filter/eyepiece tube unscrewed from the body.
As far as the frozen allen head screws go, time for the drill if they are stripped. I don’t believe you need to open the body though as that blocking filter looks like the problem. It’s an easy fix once you get the replacement filter.
Every Coronado scope ever made has a rusted blocking filter after a few years and this is no exception. That is the #1 cause of contrast loss.
I’m sure the others will chime in with their suggestions as well.


Stephen W. Ramsden
Atlanta, GA USA
Founder/Director Charlie Bates Solar Astronomy Project
http://www.solarastronomy.org
Steve Rosenow
The Sun?
The Sun?
Posts: 6
Joined: Tue Mar 06, 2018 8:04 am

Re: New member here, PST woes.

Post by Steve Rosenow »

That's strange, according to Meade, the PST's etalons are in the eyepiece tube assembly.


Current and Former Equipment Roster:

8-inch Meade LX5/2080 (Retired; Sold January 2015)
10-inch Meade 2120/LX-6 f6.3 Premiere Edition. (Retired; Fork Mount Sold July 2014)
10-inch Meade LX200 Classic f/6.3 Wide Field
Coronado PST
Meade DS2090 OTA (Reserve status May, 2017)
Meade 80mm Series 5000 ED Apochromat (On loan, May 2017)
Meade ETX-70
Nikon D5100 (#1; Decommissioned March 2016 | #2 Purchased February 2017)
Nikon D5500


Software:
Autostakkert!2 / Autostakkert!3
Registax 6
Deep Sky Stacker 3.3.4
Adobe Photoshop CS6
Adobe Lightroom 6.1
User avatar
robert
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3065
Joined: Fri Oct 14, 2011 1:49 pm
Location: N.W.Scotland
Has thanked: 4 times
Been thanked: 1252 times
Contact:

Re: New member here, PST woes.

Post by robert »

solarchat wrote: Tue Mar 06, 2018 8:49 am P.S. not to be the bearer of bad news but that is the most rusted blocking filter I have ever seen...and I’ve seen a few.
Every Coronado scope ever made has a rusted blocking filter after a few years and this is no exception. That is the #1 cause of contrast loss.
I’m sure the others will chime in with their suggestions as well.
I agree with Stephen that is a bad blocking filter and the etalon is at the other end of the black box, with the rubber ring. All sortable, the pentaprism needs to be roughly aligned to avoid astigmatism, but is is only loosely attached to anything, but is not your main problem.

Good luck
Robert


images and animations http://tinyurl.com/h5bgoso
2024 images https://www.flickr.com/photos/69734017@ ... 0313830045
2023 images https://www.flickr.com/photos/69734017@ ... 0304905278
2022 images https://www.flickr.com/photos/69734017@ ... 0295810277
ED80. ED100. SW200. Celestron-150mm-PST mod. C8 edge. ES127
LS60PT-LS60F-B1200. B600-Cak. PGR-Ch3-IMX265
User avatar
Montana
Librarian
Librarian
Posts: 34527
Joined: Mon Oct 17, 2011 5:25 pm
Location: Cheshire, UK
Has thanked: 17523 times
Been thanked: 8763 times

Re: New member here, PST woes.

Post by Montana »

I agree with Stephen also, the etalon is where the rubber tuning ring is at the base of the gold tube, have you ever tuned the etalon? try tuning it to improve surface contrast. This is the eyepiece end shown in the picture with a bad filter. I hope your etalon has not decontacted, when mine was decontacted I didn't have ghosts either I just couldn't get it on band - no surface contrast, turned out just one spacer was bad.

Alexandra


Steve Rosenow
The Sun?
The Sun?
Posts: 6
Joined: Tue Mar 06, 2018 8:04 am

Re: New member here, PST woes.

Post by Steve Rosenow »

Montana wrote: Tue Mar 06, 2018 9:24 pm I agree with Stephen also, the etalon is where the rubber tuning ring is at the base of the gold tube, have you ever tuned the etalon? try tuning it to improve surface contrast. This is the eyepiece end shown in the picture with a bad filter. I hope your etalon has not decontacted, when mine was decontacted I didn't have ghosts either I just couldn't get it on band - no surface contrast, turned out just one spacer was bad.

Alexandra
How did you fix it? It doesn't seem to be decontacted, and I can get it to show filaments and the chromosphere/prominences, but the contrast isn't as sharp as it was when I picked it up.

All suggestions I've seen say it has to be shipped back to Meade. I can't afford to do that and would rather fix it myself if there's a way to do so.


Current and Former Equipment Roster:

8-inch Meade LX5/2080 (Retired; Sold January 2015)
10-inch Meade 2120/LX-6 f6.3 Premiere Edition. (Retired; Fork Mount Sold July 2014)
10-inch Meade LX200 Classic f/6.3 Wide Field
Coronado PST
Meade DS2090 OTA (Reserve status May, 2017)
Meade 80mm Series 5000 ED Apochromat (On loan, May 2017)
Meade ETX-70
Nikon D5100 (#1; Decommissioned March 2016 | #2 Purchased February 2017)
Nikon D5500


Software:
Autostakkert!2 / Autostakkert!3
Registax 6
Deep Sky Stacker 3.3.4
Adobe Photoshop CS6
Adobe Lightroom 6.1
User avatar
Montana
Librarian
Librarian
Posts: 34527
Joined: Mon Oct 17, 2011 5:25 pm
Location: Cheshire, UK
Has thanked: 17523 times
Been thanked: 8763 times

Re: New member here, PST woes.

Post by Montana »

If you still see good overall surface contrast then the problem is the rusty filter, it needs replacing. I think there are plenty of people on the solarscope modifications section who have replaced these filters. You need to ask Mark Townley or Merlin66.

Alexandra


User avatar
Merlin66
Librarian
Librarian
Posts: 3970
Joined: Tue Dec 13, 2011 1:23 pm
Location: Junortoun, Australia
Has thanked: 173 times
Been thanked: 615 times
Contact:

Re: New member here, PST woes.

Post by Merlin66 »

The ITF filter at the base of the eyepiece holder tube (the one shown in the submitted photo) can easy be replaced with a "drop in" replacement from Maier Photonics
http://maierphotonics.com/656bandpassfilter.aspx


"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy  
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
Steve Rosenow
The Sun?
The Sun?
Posts: 6
Joined: Tue Mar 06, 2018 8:04 am

Re: New member here, PST woes.

Post by Steve Rosenow »

So when I purchase the replacement, which side goes up? I would assume one side is red, the other blue?


Current and Former Equipment Roster:

8-inch Meade LX5/2080 (Retired; Sold January 2015)
10-inch Meade 2120/LX-6 f6.3 Premiere Edition. (Retired; Fork Mount Sold July 2014)
10-inch Meade LX200 Classic f/6.3 Wide Field
Coronado PST
Meade DS2090 OTA (Reserve status May, 2017)
Meade 80mm Series 5000 ED Apochromat (On loan, May 2017)
Meade ETX-70
Nikon D5100 (#1; Decommissioned March 2016 | #2 Purchased February 2017)
Nikon D5500


Software:
Autostakkert!2 / Autostakkert!3
Registax 6
Deep Sky Stacker 3.3.4
Adobe Photoshop CS6
Adobe Lightroom 6.1
Steve Rosenow
The Sun?
The Sun?
Posts: 6
Joined: Tue Mar 06, 2018 8:04 am

Re: New member here, PST woes.

Post by Steve Rosenow »

How long would shipping take if I were to order that in a week? I hope to have the PST 'fixed' by May 11th.


Current and Former Equipment Roster:

8-inch Meade LX5/2080 (Retired; Sold January 2015)
10-inch Meade 2120/LX-6 f6.3 Premiere Edition. (Retired; Fork Mount Sold July 2014)
10-inch Meade LX200 Classic f/6.3 Wide Field
Coronado PST
Meade DS2090 OTA (Reserve status May, 2017)
Meade 80mm Series 5000 ED Apochromat (On loan, May 2017)
Meade ETX-70
Nikon D5100 (#1; Decommissioned March 2016 | #2 Purchased February 2017)
Nikon D5500


Software:
Autostakkert!2 / Autostakkert!3
Registax 6
Deep Sky Stacker 3.3.4
Adobe Photoshop CS6
Adobe Lightroom 6.1
User avatar
Merlin66
Librarian
Librarian
Posts: 3970
Joined: Tue Dec 13, 2011 1:23 pm
Location: Junortoun, Australia
Has thanked: 173 times
Been thanked: 615 times
Contact:

Re: New member here, PST woes.

Post by Merlin66 »

Easy, the shiny side towards the front - facing the incoming light.


"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy  
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
User avatar
Merlin66
Librarian
Librarian
Posts: 3970
Joined: Tue Dec 13, 2011 1:23 pm
Location: Junortoun, Australia
Has thanked: 173 times
Been thanked: 615 times
Contact:

Re: New member here, PST woes.

Post by Merlin66 »

Maier are usually pretty prompt....I assume you're in the US?


"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy  
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
Steve Rosenow
The Sun?
The Sun?
Posts: 6
Joined: Tue Mar 06, 2018 8:04 am

Re: New member here, PST woes.

Post by Steve Rosenow »

Merlin66 wrote: Fri Mar 09, 2018 6:15 am Maier are usually pretty prompt....I assume you're in the US?
Yes. Washington state.


Current and Former Equipment Roster:

8-inch Meade LX5/2080 (Retired; Sold January 2015)
10-inch Meade 2120/LX-6 f6.3 Premiere Edition. (Retired; Fork Mount Sold July 2014)
10-inch Meade LX200 Classic f/6.3 Wide Field
Coronado PST
Meade DS2090 OTA (Reserve status May, 2017)
Meade 80mm Series 5000 ED Apochromat (On loan, May 2017)
Meade ETX-70
Nikon D5100 (#1; Decommissioned March 2016 | #2 Purchased February 2017)
Nikon D5500


Software:
Autostakkert!2 / Autostakkert!3
Registax 6
Deep Sky Stacker 3.3.4
Adobe Photoshop CS6
Adobe Lightroom 6.1
Post Reply