Coronado PST and FOCUS

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
Lunam
The Sun?
The Sun?
Posts: 4
Joined: Thu Apr 28, 2016 8:35 am

Coronado PST and FOCUS

Post by Lunam »

I have been using my Coronado PST and have been able to do visual of the sun and very pleased with the results. Using my 3.5mm Orion Stratus Wide-Field Eyepiece got amazing views

However I have not been able to image because of the back focus issue with the telescope.

I tried the ZWO 120 mono camera and I was able to get a nice white circle but no detail at all (could not see sunspots or flares at all I reach the end of the focusing to get the white circle)

I tried doing eye piece projection with my Nikon and Celeston Deluxe tele extender but could never get to focus.
I have ordered a 1.25 Shorty Barlow to see if this helps
Any suggestions/pointers will be greatly appreciated
LS


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: Coronado PST and FOCUS

Post by Merlin66 »

Welcome on board.
The PST was designed as a visual instrument.
To achieve the backfocus you need for a camera there are a couple of options...
Add a barlow lens to the eyepiece section or look at removing about 5mm from the end of the eyepiece section (very very carefully - the final blocking filter should be protected from damage.)


"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
Lunam
The Sun?
The Sun?
Posts: 4
Joined: Thu Apr 28, 2016 8:35 am

Re: Coronado PST and FOCUS

Post by Lunam »

Thanks I just ordered a 2x Barlow. Will try it as soon as I get it I have a 5x but have not tried it. Will let tou know what I achieve when I get it
Appreciate the help


User avatar
Montana
Librarian
Librarian
Posts: 34527
Joined: Mon Oct 17, 2011 5:25 pm
Location: Cheshire, UK
Has thanked: 17526 times
Been thanked: 8763 times

Re: Coronado PST and FOCUS

Post by Montana »

5x will be way too much for the PST. A 2x and 1.6x will be great. I use a very short shoulderless nose piece on my camera to get focus at native focal length. However on the newer versions of the PST the eyepiece holder is 5mm longer than mine so even the shoulderless nosepiece won't work, you have to shave that 5mm off.

Alexandra


Lunam
The Sun?
The Sun?
Posts: 4
Joined: Thu Apr 28, 2016 8:35 am

Re: Coronado PST and FOCUS

Post by Lunam »

Thank you guys for your help
I was able to finally get some pics (even tried afocal)
Waiting for the 2x Barlow to arrive.
Got something now have to work on making them better.
Wished the Newton rings could be avoided
Attachments
SUNspot1.jpg
SUNspot1.jpg (36.79 KiB) Viewed 5097 times
sun flares BW.jpg
sun flares BW.jpg (32.11 KiB) Viewed 5097 times
Afocal attempt.jpg
Afocal attempt II.jpg
Afocal attempt II.jpg (49.25 KiB) Viewed 5097 times


Lunam
The Sun?
The Sun?
Posts: 4
Joined: Thu Apr 28, 2016 8:35 am

Re: Coronado PST and FOCUS

Post by Lunam »

Thank you guys for your help
I was able to finally get some pics (even tried afocal)
Waiting for the 2x Barlow to arrive.
Got something now have to work on making them better.
Wished the Newton rings could be avoided
Attachments
Afocal attempt II.jpg
Afocal attempt II.jpg (49.25 KiB) Viewed 5097 times


User avatar
Montana
Librarian
Librarian
Posts: 34527
Joined: Mon Oct 17, 2011 5:25 pm
Location: Cheshire, UK
Has thanked: 17526 times
Been thanked: 8763 times

Re: Coronado PST and FOCUS

Post by Montana »

These are great, what did you do?

Alexandra


Post Reply