PST mod Telescope question.

Frankenscope? Let's see it!***be advised that NOTHING in this forum has been safety tested and you are reading and using these posts at your own peril. blah, blah, blah... dont mess around with your eyesight when it comes to solar astronomy. Use appropriate filtration at all times...
Post Reply
User avatar
aboy
Ohhhhhh My!
Ohhhhhh My!
Posts: 162
Joined: Thu May 23, 2013 4:35 am
Location: Ventura County, California

PST mod Telescope question.

Post by aboy » Sat Dec 19, 2015 2:39 pm

I there.

I just have a silly question here.

For a PST mod I know it's better a F/10 refractor scope. But, I was reading about the lunt 100 specifications and I find out that is like the Explorer Scientific 102.

My question here is:

It is possible to use the ES 102 on the PST modification as well?

Here are the specifications on both scopes:

Code: Select all

LS100THa scope Specifications (Single Stack)

Optical Aperture: 102 mm
Etalon: Internal <0.7 Angstrom
Tuning: Internal Pressure Tune (Doppler True Tuning)
Focal Length: 714 mm
F Ratio: F/7
Focuser: 2″ Feather-Touch focuser with 10:1 reduction
Tube diameter: 121 mm
Tube length with blocking filter: 634 mm
Storage: Aluminum finished hard case with fitted foam
Weight: 12.2 lb

Code: Select all

ES-ED102mm Essential Series Aluminum Air-Spaced Triplet Refractor
Item Number	ES-ED10207-01
Optical Aperture: 102 mm
Focal Length	714mm
Focal Ratio	f/7
Limiting
Magnitude	12.5
Resolution	1.14 arcsec
Tube Length
w/ Dew Shield	30.5"; 774mm
Tube Length
w/out Dew Shield	23.75"; 603mm
Diameter	119mm
Weight	9.6 lb; 4.4 kg
Thanks for all your time guys.
"I'm enough of an artist to draw freely on my imagination. Imagination is more important than knowledge. Knowledge is limited; imagination encircles the world."

--Albert Einstein, October 26, 1929
------------------------------------------------------------

EQ:

Double stack 60mm Coronado ( pre-meade ) H-alpha filters with a 15 blocking filter.

DMK 51AU02 the imaging source Mono CCD camera.

Orion Short 2x Barlow.

Explore Scientific 102mm f/7 Air-Spaced Triplet ED Apochromatic Refractor Telescope.

Astrotelescope ( Planet Killer ) 102mm f/11 hand corrected doublet. Refractor Telescope.

Losmandy - G11 ( Gemini 1 )

FireCapture, AutoStakkert 2, PixInsight, Registack 6 and Photoshop CS 6.

User avatar
Merlin66
Librarian
Librarian
Posts: 3170
Joined: Tue Dec 13, 2011 1:23 pm
Location: St Leonards, Australia
Contact:

Re: PST mod Telescope question.

Post by Merlin66 » Sat Dec 19, 2015 9:09 pm

You could use the 102/714 with the PST Mod, but it would be restricted to an effective aperture of 71mm (714/10).
Alternatively you could replace the front barlow element of the PST assembly with a -140mm barlow to give the full 102mm.
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.yahoo.com/neo/groups/ast ... scopy/info
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer

User avatar
aboy
Ohhhhhh My!
Ohhhhhh My!
Posts: 162
Joined: Thu May 23, 2013 4:35 am
Location: Ventura County, California

Re: PST mod Telescope question.

Post by aboy » Sat Dec 19, 2015 11:42 pm

Merlin66 wrote:You could use the 102/714 with the PST Mod, but it would be restricted to an effective aperture of 71mm (714/10).
Alternatively you could replace the front barlow element of the PST assembly with a -140mm barlow to give the full 102mm.

How I can replace the Barlow ?
"I'm enough of an artist to draw freely on my imagination. Imagination is more important than knowledge. Knowledge is limited; imagination encircles the world."

--Albert Einstein, October 26, 1929
------------------------------------------------------------

EQ:

Double stack 60mm Coronado ( pre-meade ) H-alpha filters with a 15 blocking filter.

DMK 51AU02 the imaging source Mono CCD camera.

Orion Short 2x Barlow.

Explore Scientific 102mm f/7 Air-Spaced Triplet ED Apochromatic Refractor Telescope.

Astrotelescope ( Planet Killer ) 102mm f/11 hand corrected doublet. Refractor Telescope.

Losmandy - G11 ( Gemini 1 )

FireCapture, AutoStakkert 2, PixInsight, Registack 6 and Photoshop CS 6.

User avatar
Merlin66
Librarian
Librarian
Posts: 3170
Joined: Tue Dec 13, 2011 1:23 pm
Location: St Leonards, Australia
Contact:

Re: PST mod Telescope question.

Post by Merlin66 » Sun Dec 20, 2015 12:02 am

The front barlow lens of the PST assembly can be easily removed and replaced with a 25mm -140mm barlow - if you can find one from Thorlabs/ Edmund Optics.
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.yahoo.com/neo/groups/ast ... scopy/info
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3055
Joined: Sun Nov 18, 2012 3:13 pm

Re: PST mod Telescope question.

Post by Valery » Sun Dec 20, 2015 12:41 am

Merlin66 wrote:The front barlow lens of the PST assembly can be easily removed and replaced with a 25mm -140mm barlow - if you can find one from Thorlabs/ Edmund Optics.

It can't work as designed in the PST or close. Two lenses - barlow negative and a second positive (refocusing objective) works as a whole system and they
have no spherical aberration, no coma and astigmatism. If one change one lens with unknown radii, then absolutely no warranty that these aberrations will be fixed in a new system. More so, we can state, that they will not be fixed.

Better to change F/7 cone to F/10 with regular Barlow lens or with a special barlow lens. The PST etalon block better be work with it's native lens system.


Valery.
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.

Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.

User avatar
Merlin66
Librarian
Librarian
Posts: 3170
Joined: Tue Dec 13, 2011 1:23 pm
Location: St Leonards, Australia
Contact:

Re: PST mod Telescope question.

Post by Merlin66 » Sun Dec 20, 2015 1:00 am

Valery,
I hear you, but many amateurs have already successfully changed the front barlow element in PST mods.
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.yahoo.com/neo/groups/ast ... scopy/info
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3055
Joined: Sun Nov 18, 2012 3:13 pm

Re: PST mod Telescope question.

Post by Valery » Mon Dec 21, 2015 2:05 pm

Merlin66 wrote:Valery,
I hear you, but many amateurs have already successfully changed the front barlow element in PST mods.
But I never saw crystal clear razor sharp images taken with PST etalon with randomly chosen lenses.
So, the "success", I suspect, is limited.


Valery.
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.

Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.

User avatar
aboy
Ohhhhhh My!
Ohhhhhh My!
Posts: 162
Joined: Thu May 23, 2013 4:35 am
Location: Ventura County, California

Re: PST mod Telescope question.

Post by aboy » Mon Dec 21, 2015 6:05 pm

Well. Thank you guys for all the answers.
"I'm enough of an artist to draw freely on my imagination. Imagination is more important than knowledge. Knowledge is limited; imagination encircles the world."

--Albert Einstein, October 26, 1929
------------------------------------------------------------

EQ:

Double stack 60mm Coronado ( pre-meade ) H-alpha filters with a 15 blocking filter.

DMK 51AU02 the imaging source Mono CCD camera.

Orion Short 2x Barlow.

Explore Scientific 102mm f/7 Air-Spaced Triplet ED Apochromatic Refractor Telescope.

Astrotelescope ( Planet Killer ) 102mm f/11 hand corrected doublet. Refractor Telescope.

Losmandy - G11 ( Gemini 1 )

FireCapture, AutoStakkert 2, PixInsight, Registack 6 and Photoshop CS 6.

User avatar
marktownley
Librarian
Librarian
Posts: 24543
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Contact:

Re: PST mod Telescope question.

Post by marktownley » Mon Dec 21, 2015 9:27 pm

It's all about compromises this modding; unless you're using bespoke designed optics for a project there will always be a price to pay in terms of image quality. I modded a 70mm f6 refractor to use with a PST mod, I was pleased with the results. At the end of the day it's a way of getting a result without spending big bucks.
Image
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!

User avatar
aboy
Ohhhhhh My!
Ohhhhhh My!
Posts: 162
Joined: Thu May 23, 2013 4:35 am
Location: Ventura County, California

Re: PST mod Telescope question.

Post by aboy » Wed Dec 23, 2015 12:30 pm

marktownley wrote:It's all about compromises this modding; unless you're using bespoke designed optics for a project there will always be a price to pay in terms of image quality. I modded a 70mm f6 refractor to use with a PST mod, I was pleased with the results. At the end of the day it's a way of getting a result without spending big bucks.
Well, Like you say.

I do want the mod for HD pictures, and I hear you guys that my Astrotelescope 102 f/11 will do the job. But, I always was wonder if I can get the ES102ED Working for this mod as well.

Thanks you guys for your the answers.
"I'm enough of an artist to draw freely on my imagination. Imagination is more important than knowledge. Knowledge is limited; imagination encircles the world."

--Albert Einstein, October 26, 1929
------------------------------------------------------------

EQ:

Double stack 60mm Coronado ( pre-meade ) H-alpha filters with a 15 blocking filter.

DMK 51AU02 the imaging source Mono CCD camera.

Orion Short 2x Barlow.

Explore Scientific 102mm f/7 Air-Spaced Triplet ED Apochromatic Refractor Telescope.

Astrotelescope ( Planet Killer ) 102mm f/11 hand corrected doublet. Refractor Telescope.

Losmandy - G11 ( Gemini 1 )

FireCapture, AutoStakkert 2, PixInsight, Registack 6 and Photoshop CS 6.

Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests