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Coronado PST and FOCUS

Posted: Thu Apr 28, 2016 8:40 am
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

Re: Coronado PST and FOCUS

Posted: Fri Apr 29, 2016 2:51 am
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.)

Re: Coronado PST and FOCUS

Posted: Fri Apr 29, 2016 3:02 am
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

Re: Coronado PST and FOCUS

Posted: Sun May 01, 2016 5:47 pm
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

Re: Coronado PST and FOCUS

Posted: Tue May 03, 2016 7:34 pm
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

Re: Coronado PST and FOCUS

Posted: Tue May 03, 2016 7:34 pm
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

Re: Coronado PST and FOCUS

Posted: Wed May 04, 2016 9:28 am
by Montana
These are great, what did you do?

Alexandra