Appenzellersonne, "small" scope modification
- swisswalter
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Appenzellersonne, "small" scope modification
Hi all
first I ask for forgiveness for the bad weather ahead in Europe. I guess it'll take 6 weeks until the weather god has calmed down again.
My newest plans are moding this scope to a Ha-gun (150/3000, some 50 years old)
First inspection in the living room after a 500 miles drive to pic it up
Well there is need of some modifications or does anybody know of a 1,3 " focuser to hold this eyepiece ?
this special focuser locking needs fixing as well (fiberboard, stone, felt and chipboard)
the special feature of that scope is the length of the focuser, 1000 mm inward travel
I'm back in 4 weeks, hopefully, for the first light
first I ask for forgiveness for the bad weather ahead in Europe. I guess it'll take 6 weeks until the weather god has calmed down again.
My newest plans are moding this scope to a Ha-gun (150/3000, some 50 years old)
First inspection in the living room after a 500 miles drive to pic it up
Well there is need of some modifications or does anybody know of a 1,3 " focuser to hold this eyepiece ?
this special focuser locking needs fixing as well (fiberboard, stone, felt and chipboard)
the special feature of that scope is the length of the focuser, 1000 mm inward travel
I'm back in 4 weeks, hopefully, for the first light
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
Oh wow! thats fantastic! B)
That must have cost you a fair few pairs of shoes walter, my wife thinks my 127mm frac is huge... This one is a beast! :
That must have cost you a fair few pairs of shoes walter, my wife thinks my 127mm frac is huge... This one is a beast! :
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Re: Appenzellersonne, small scope modification
Hi Mark
thank you very much for your fast feed back. Yes, expensive in point of pairs of shoes. The deal was 1 week wellness holiday in a spa against the scope
thank you very much for your fast feed back. Yes, expensive in point of pairs of shoes. The deal was 1 week wellness holiday in a spa against the scope
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
lol, I know what you mean. My PST mod cost me a weeks holiday somewhere (hasn't decided where yet) at the start of June in the UK, I might not have mentioned it's the same week as the transit of Venus though I can forsee a cottage somewhere with a sea view to the north east... :whistle:
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Re: Appenzellersonne, small scope modification
Whooo
I thought my "Big Yin" 150/1200 was BIG......
I think the answer would be to do a re-build of the rear section and end up with an adaptor plate which would take a TS 2" Crayford...
What do you have in mind for this?? The ultimate PST mod???
At a base of f20 this could be very interesting!!!
With one of Cata's "new" E-ERF? (E for Economy!)
I thought my "Big Yin" 150/1200 was BIG......
I think the answer would be to do a re-build of the rear section and end up with an adaptor plate which would take a TS 2" Crayford...
What do you have in mind for this?? The ultimate PST mod???
At a base of f20 this could be very interesting!!!
With one of Cata's "new" E-ERF? (E for Economy!)
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
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Re: Appenzellersonne, small scope modification
Hi Ken
thank you very much. I'm so excited that I can't wait to have first light.
Yes I will have let done an adoption of the focuser to a 2" crayford 1:10. I'll use my 150 mm D-ERF I already have.
Me too I wonder what f/20 is showing with this tiny PST etalon. Maybe a disappointment or a big move forward or as usual in life, something in between.
thank you very much. I'm so excited that I can't wait to have first light.
Yes I will have let done an adoption of the focuser to a 2" crayford 1:10. I'll use my 150 mm D-ERF I already have.
Me too I wonder what f/20 is showing with this tiny PST etalon. Maybe a disappointment or a big move forward or as usual in life, something in between.
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
Hi Mark
you are a fox north east view :whistle: I won't reveal your secret
you are a fox north east view :whistle: I won't reveal your secret
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
Hmmm
Interesting....
With the 150 D-ERF it will still function as a f20 system, but...
The size of the solar disk at the etalon will be 30mm (3000/100) plus the 200/10=20mm this is obviously much larger than the etalon so there will be significant vignetting.
Infact, at f20 it may be worth while considering the removal of the front and rear etalon lens and use the "bare" etalon in a f20 beam.....
Interesting....
With the 150 D-ERF it will still function as a f20 system, but...
The size of the solar disk at the etalon will be 30mm (3000/100) plus the 200/10=20mm this is obviously much larger than the etalon so there will be significant vignetting.
Infact, at f20 it may be worth while considering the removal of the front and rear etalon lens and use the "bare" etalon in a f20 beam.....
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
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"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
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Re: Appenzellersonne, small scope modification
Hi Ken
thank you very much for that hint. I have not thought about that. Yes that will be mod phase 3, as soon as I have seen that mod 2 is working. I'll come back to that issue when I have to remove the mini ERF and the front and back lens.
I have still another option. A spare LUNT LS50 for mods
What would you be doing, granted the scope works at all, which has not yet been profen
thank you very much for that hint. I have not thought about that. Yes that will be mod phase 3, as soon as I have seen that mod 2 is working. I'll come back to that issue when I have to remove the mini ERF and the front and back lens.
I have still another option. A spare LUNT LS50 for mods
What would you be doing, granted the scope works at all, which has not yet been profen
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
Re: Appenzellersonne, small scope modification
Wow, Walter. That’s serious modding. The Lunt LS50 option would be very interesting.
Viljo
Viljo
Re: Appenzellersonne, small scope modification
Amazing telescope Walter. Does it actually say 3000mm FL on it, I ask this as telescopes of this design often include erecting systems which extend the focus position, the native focal length of the could be shorter than F20.
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Re: Appenzellersonne, small scope modification
Hi Chaps
thank you very much for your input.
The FL is nativ 3000 mm , I measured it, no lenses between objektif and ocular at all.
It has a very special desing. You can shorten it down to 2000 mm and so it fits in almost any car.
Yes Cai Uso deflection could be a big problem, on the other hand I have already a solution to it, if I'll get into problems. I'll construct something like a bridge stiffening with wires
I'll shoot pics of the lens and present them here, but only if the first light is reasonably good, otherwise it just was a miss buy
thank you very much for your input.
The FL is nativ 3000 mm , I measured it, no lenses between objektif and ocular at all.
It has a very special desing. You can shorten it down to 2000 mm and so it fits in almost any car.
Yes Cai Uso deflection could be a big problem, on the other hand I have already a solution to it, if I'll get into problems. I'll construct something like a bridge stiffening with wires
I'll shoot pics of the lens and present them here, but only if the first light is reasonably good, otherwise it just was a miss buy
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
it may be worth while considering the removal of the front and rear etalon lens and use the "bare" etalon in a f20 beam.....
What happens if those lenses are removed? How does that affect focusing?
I'm curious now.
What happens if those lenses are removed? How does that affect focusing?
I'm curious now.
Re: Appenzellersonne, small scope modification
This would be a great scope for a custom telecentric and the LS50 etalon!
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Re: Appenzellersonne, small scope modification
Hi Peter, John and Colin
thank you very much.
Colin, would you show us in a little drawing how you see the setup. Has it to be a custom made telecentric, would a Baader TZ4 not work?
thank you very much.
Colin, would you show us in a little drawing how you see the setup. Has it to be a custom made telecentric, would a Baader TZ4 not work?
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
John,
A bare etalon at f25 or so has been used in prior mods. I haven't seen any images from such a system. Based on previous discussion (check out the telecentric threads)it would be marginal at f20....
Other than the etalon filtering effects, the other other thing would be an reduction in the back distance due to the amount of glass "in the converging beam" (similar to the effect of a filter in a "normal" telescope. This is approx 1/3 the thickness; if the total etalon plates are say 15mm thick this would give a 5mm reduction.
The bare etalon, in the 150/3000 scope would be placed close to focus to minimise vignetting.
A bare etalon at f25 or so has been used in prior mods. I haven't seen any images from such a system. Based on previous discussion (check out the telecentric threads)it would be marginal at f20....
Other than the etalon filtering effects, the other other thing would be an reduction in the back distance due to the amount of glass "in the converging beam" (similar to the effect of a filter in a "normal" telescope. This is approx 1/3 the thickness; if the total etalon plates are say 15mm thick this would give a 5mm reduction.
The bare etalon, in the 150/3000 scope would be placed close to focus to minimise vignetting.
"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
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
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Re: Appenzellersonne, small scope modification
Brilliant aquisition Walter.Most Daystar filters focus at F20+ have you got one of those floating around. I don't know much about this mod stuff but that scope looks promising.
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Re: Appenzellersonne, small scope modification
Hi Ken, Hi Derek
thank you very much.
@Derek I used to have a Daystar, then sold it, because it makes more fun with the PST mod's. Now I have another Daystar filter, possibly broken (blind chicken thread), but I have yet to test it.
It all takes some time
thank you very much.
@Derek I used to have a Daystar, then sold it, because it makes more fun with the PST mod's. Now I have another Daystar filter, possibly broken (blind chicken thread), but I have yet to test it.
It all takes some time
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
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Re: Appenzellersonne, small scope modification
Hi Apollo
thank you very much. I'll have a read later
thank you very much. I'll have a read later
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
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Re: Appenzellersonne, small scope modification
Hi Walter
That is quite a scope...that will take quite a mount...that might take a month at the spa
Hope your plans to mod it go well.
Brian
That is quite a scope...that will take quite a mount...that might take a month at the spa
Hope your plans to mod it go well.
Brian
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ASI1600MM, ASI432MM, ASI294MM Pro, ASI174MM, ASI462MM
Maple Ridge Observatory
Cambray, ON Canada
Photos: https://www.flickr.com/photos/185395281@N08/albums
10'x15 Roll-off Roof Observatory
Takahashi EM400 Mount carrying:
C14 + Lunt 80ED
Deep Sky Work - ASI294MM Pro+EFW 7x36/Canon 60D (Ha mod), ONAG
Planetary Work - SBIG CFW10, ASI462MM
2.2m Diameter Dome
iOptron CEM70G Mount carrying:
Orion EON 130ED, f7 OTA for Day & Night Use
Ha Setup: Lunt LS80PT/LS75FHa/B1200Ha + Home Brew Lunt Double Stack/B1800Ha on the Orion OTA + Daystar Quantum
WL, G-Band & CaK Setup: Lunt Wedge & Lunt B1800CaK, Baader K-Line and Altair 2nm G-Band filter
ASI1600MM, ASI432MM, ASI294MM Pro, ASI174MM, ASI462MM
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Re: Appenzellersonne, small scope modification
Hi Brian
thank you very much. Yes 1 month of spa or 100 pair of shoes
I'm on the way fixing little things on the scope. I'm expecting the focuser adapter arriving in 3 weeks (honestly, I can't wait, it hurts)
thank you very much. Yes 1 month of spa or 100 pair of shoes
I'm on the way fixing little things on the scope. I'm expecting the focuser adapter arriving in 3 weeks (honestly, I can't wait, it hurts)
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
Hi all
it took a long time to get all the parts in the right condition, some of them had to be returned 3 times to the vendor until they matched the specs
today was the first setup and the first light:
notice the counter weight hmy: :woohoo:
the first pic (note seeing very horrible)
Now I have to work on a decent solution for the balance on the mount and alter the last aperture (too much scattered light, straiglight) . Later on maybe I mount a motorfocus.
I found it very difficult to find focus, there was so much way in betweeen some focus and less focus, with my f/10 systems there is no question about focused or not focused, maybe you have a hint
Attached files
it took a long time to get all the parts in the right condition, some of them had to be returned 3 times to the vendor until they matched the specs
today was the first setup and the first light:
notice the counter weight hmy: :woohoo:
the first pic (note seeing very horrible)
Now I have to work on a decent solution for the balance on the mount and alter the last aperture (too much scattered light, straiglight) . Later on maybe I mount a motorfocus.
I found it very difficult to find focus, there was so much way in betweeen some focus and less focus, with my f/10 systems there is no question about focused or not focused, maybe you have a hint
Attached files
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
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Re: Appenzellersonne, small scope modification
Walter,
I have the same issues focusing the spectroscopes...
The depth of focus (for 1/4 wave accuracy) is somewhere around:
delta f = 1.6 F^2 lambda
where F is the focal ratio and lambda the wavelength.
i.e. for a f10 system at green light this is around 0.22mm, so with your "new" friend it will be much more.....
I have the same issues focusing the spectroscopes...
The depth of focus (for 1/4 wave accuracy) is somewhere around:
delta f = 1.6 F^2 lambda
where F is the focal ratio and lambda the wavelength.
i.e. for a f10 system at green light this is around 0.22mm, so with your "new" friend it will be much more.....
"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
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
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Re: Appenzellersonne, small scope modification
Hi Ken
thank you very much. That is a very good explanation, which I as a chemist can understand. I am going into it the day after tomorrow. I'm still hoping for that cloud gap in the morning of the 6th
thank you very much. That is a very good explanation, which I as a chemist can understand. I am going into it the day after tomorrow. I'm still hoping for that cloud gap in the morning of the 6th
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
Re: Appenzellersonne, small scope modification
Walter,
I have the same issues focusing the spectroscopes...
The depth of focus (for 1/4 wave accuracy) is somewhere around:
delta f = 1.6 F^2 lambda
where F is the focal ratio and lambda the wavelength.
i.e. for a f10 system at green light this is around 0.22mm, so with your "new" friend it will be much more.....
I thought that long focal ratio scopes were more forgiving to focus error? That is at least what my DOS ray tracing software says.
I have the same issues focusing the spectroscopes...
The depth of focus (for 1/4 wave accuracy) is somewhere around:
delta f = 1.6 F^2 lambda
where F is the focal ratio and lambda the wavelength.
i.e. for a f10 system at green light this is around 0.22mm, so with your "new" friend it will be much more.....
I thought that long focal ratio scopes were more forgiving to focus error? That is at least what my DOS ray tracing software says.
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Re: Appenzellersonne, small scope modification
Yes,
that's correct. It varies as the square of the f ratio.
eg At f4 it's 0.035mm, at f8 it's 0.141mm and f10 gives 0.22mm
that's correct. It varies as the square of the f ratio.
eg At f4 it's 0.035mm, at f8 it's 0.141mm and f10 gives 0.22mm
"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
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
- swisswalter
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Re: Appenzellersonne, small scope modification
Hi Joe
thank you very much
thank you very much
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
- swisswalter
- Way More Fun to Share It!!
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Re: Appenzellersonne, small scope modification
Hi Ken
pic 09244, close up of the focuser, is the PST mod
pic 09244, close up of the focuser, is the PST mod
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa