Search found 63 matches

by antonello
Tue Sep 04, 2018 10:35 am
Forum: Solar Scope Modifications
Topic: lunt 50 mod
Replies: 26
Views: 3222

Re: lunt 50 mod

After a long time, during which no one knew if the Lunt 50 had a lens with a single lens or an achromatic lens, I discovered from this image lunt 50.jpg that even the Lunt 50, like the Lunt 60., seems to have a objective with single lens, and therefore the use of the Etalon of the Lunt 50, together ...
by antonello
Tue Aug 28, 2018 5:32 am
Forum: Solar Scope Modifications
Topic: The Double pass idea...
Replies: 20
Views: 957

Re: The Double pass idea...

Hi TheSkyBurner,
because we are trying to do the same thing, I with pessimism and you with optimism, we stay in touch. In the coming days I can put some pictures of my experiment ...
by antonello
Mon Aug 27, 2018 5:38 am
Forum: Solar Scope Modifications
Topic: The Double pass idea...
Replies: 20
Views: 957

Re: The Double pass idea...

At what price? The fact remains that if your beam splitter is semi-polarized, the image and all the reflections are semi-polarized and it is enough that a reflection has the same angle of polarization of the image to make the project a failure. However I have not discouraged you in your work (I myse...
by antonello
Tue Aug 21, 2018 6:13 am
Forum: Solar Scope Modifications
Topic: The Double pass idea...
Replies: 20
Views: 957

Re: The Double pass idea...

The issue is much more complicated than you see it. It is not always possible to put a polarizer. In the system in question, removing the reflection is not unlikely that the image will be removed ... and even if the image will not be removed, its brightness becomes even lower ... and it is already l...
by antonello
Mon Aug 20, 2018 7:15 am
Forum: Solar Scope Modifications
Topic: The Double pass idea...
Replies: 20
Views: 957

Re: The Double pass idea...

Yes, this system is old, but I have not seen many experimental applications... most it is remained in the design phase ... I myself am working for a prototype, just for the curiosity to see if work well... As Zetner said, if the beam splitter prism is polarized, the system will NOT work. To work it ...
by antonello
Thu Apr 12, 2018 11:28 am
Forum: Solar Scope Modifications
Topic: A high quality telecentric 3X made by itself
Replies: 15
Views: 1545

Re: A high quality telecentric 3X made by itself

Hello I apologize for the delay... Speaking of my telecentric, I had written to marktownley that quality decreases a little in the calcium line ... In reality this is not true, what happens is that it is the disc of difraction that in the wavelength of the calcium is half of that in H-alpha ... but ...
by antonello
Tue Mar 27, 2018 1:58 pm
Forum: Solar Scope Modifications
Topic: A high quality telecentric 3X made by itself
Replies: 15
Views: 1545

Re: A high quality telecentric 3X made by itself

Hello Maktownley I have had the time to verify the quality of my telecentric in the Calcium line. With Zemax in "optimization" mode I verified that the best scheme is the same as with H-alpha. Of course, the quality deteriorates slightly, but is always good for a field of 0.15 °, which corresponds t...
by antonello
Mon Mar 12, 2018 6:55 am
Forum: Solar Scope Modifications
Topic: A high quality telecentric 3X made by itself
Replies: 15
Views: 1545

Re: A high quality telecentric 3X made by itself

Hello Marktownley 1) Please note that this telecentric was born in the amateurs astronomers field for a telescope f: 10, to bring the focal ratio to f: 30 (3X), when the telecentric 3X Baader had not yet been released. 2) As someone else has already experienced, the focal ratio f: 30, for to make an...
by antonello
Mon Feb 12, 2018 6:57 am
Forum: Solar Scope Modifications
Topic: A high quality telecentric 3X made by itself
Replies: 15
Views: 1545

Re: A high quality telecentric 3X made by itself

Thank's. I add only some useful information (they are written in the images, but if one does not know Oslo or Zemax can not interpret it): the first negative lens must be placed just before the telescope's focus. In a 150/1500 telescope this distance is 86 mm for 3X, 92 mm for 3.3X and 113 mm for 5X...
by antonello
Thu Feb 08, 2018 12:29 pm
Forum: Solar Scope Modifications
Topic: A high quality telecentric 3X made by itself
Replies: 15
Views: 1545

A high quality telecentric 3X made by itself

Do you need a very high quality 3.3X or 3X telecentric and do you have the ability to build it? Here is my project for a telecentric suitable for a H-alpha Telescope f: 10 (I designed and built it for my 150/1500 mm h-alpha Istar). There are two projects, one of a 3.3X (OSLO) and one of 3X (ZEMAX), ...
by antonello
Thu Jan 25, 2018 8:12 am
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

Hello Merlin 66 I managed to do two small projects to be able to use the Lunt LS60 etalon with achromatic objectives. Both have two collimation lenses 30 mm diameter and -250 and +250 mm of focal. These lenses is it available in the Optosigma catalog at 25 $ each ...) The first project involves the ...
by antonello
Tue Jan 23, 2018 10:59 pm
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

For me a good solution is an achromatic 100 mm f: 10 lens (as Tal rs100). In this case (if the etalon of Lunt LS 60 is 30 mm in diameter) will be necessary to change the two original lenses of the etalon with a new pair of lenses of 30 mm in diameter and -250 mm and 250 mm of focal length (plano-con...
by antonello
Tue Jan 23, 2018 1:58 pm
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

If the Lunt internal etalon is 30mm diameter... nothing changes You can put two 30-40mm lenses with the same focal length of my Lunt 35 upgraded. Sorry, but I'm not sure I understood your question correctly. Here it is not a question of improving, but of maintaining the quality of the new objective....
by antonello
Tue Jan 23, 2018 12:54 pm
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

The two lenses required for to upgraded the Lunt LS60 with a big achromatic objective are two simple catalog lenses (about € 25 each). Their simplicity and particularity is that put in that position and in that orientation (plane / concave and convex / plane) DO NOT introduce spherical aberration. I...
by antonello
Tue Jan 23, 2018 8:26 am
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

The flu has passed ... but this time it was hard ... Summarizing... In solar telescopes with an achromatic lens, the lenses of etalon collimator system do not introduce spherical aberration and do not change the quality of the objective. Precisely for this reason it is possible to replace the object...
by antonello
Fri Jan 19, 2018 4:15 am
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

Sorry Merlin66, but I'm in bed from two days with a fever at 39 °... I hope to recover soon. Now I can not even reason...
by antonello
Wed Jan 17, 2018 9:06 am
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

No, in this case I have taken the etalon of the Lunt 35 (which is frontal to the telescope and is not inside the telescope, as it is for the Lunt 50 and the Lunt 60). My modification consists in placing the etalon of the Lunt 35 inside a new telescope with a greater diameter than 35 mm (i have taken...
by antonello
Wed Jan 17, 2018 8:32 am
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

Yes, there is an achromatic objective in the PST and that is why in the PST it is possible to replace the small 40mm lens with a larger one. In this case the quality at the center of the field remains unchanged, as can easily be verified with an optical calculation program. If instead the lens objec...
by antonello
Wed Jan 17, 2018 7:38 am
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

Unfortunately it's not like that. What you write may be good for an achromatic lens, but it's not good if the objective of the solar telescope is a single lens. Recently I read a topic in which a passionate Italian complained of a poor quality of the telescope obtained by putting an achromatic lens ...
by antonello
Tue Jan 16, 2018 3:23 pm
Forum: Solar Scope Modifications
Topic: Lunt 60 mod options??
Replies: 21
Views: 1593

Re: Lunt 60 mod options??

It's strange, it seems to me that the Lunt ls60 is equipped with a objective with only one lens, so it is not the most suitable instrument for a modification. To have a good quality with another (bigger) objective, it is necessary to replace the negative and the positive lens of the etalon collimato...
by antonello
Thu Nov 23, 2017 6:45 am
Forum: This is SolarChat !!
Topic: Lunt 50 - Single Stack / Double Stack Comparison 19th November
Replies: 22
Views: 1212

Re: Lunt 50 - Single Stack / Double Stack Comparison 19th November

Lots of people have- check out the mods section 👍 You're right, I have not seen those topics recently, ... but there are only a few people, compared to the dozens and dozens of those who used the PST Etalon part ... Now I also figured why: I thought that the etalon inside the Lunt 50 was same as Lu...
by antonello
Wed Nov 22, 2017 6:57 am
Forum: This is SolarChat !!
Topic: Sun 21 11 2017
Replies: 11
Views: 667

Re: Sun 21 11 2017

Hello Pepe
it would be useful to know what instruments you have used...
by antonello
Wed Nov 22, 2017 6:50 am
Forum: This is SolarChat !!
Topic: Lunt 50 - Single Stack / Double Stack Comparison 19th November
Replies: 22
Views: 1212

Re: Lunt 50 - Single Stack / Double Stack Comparison 19th November

Thank you for your answer. I asked this information why I did not read this anywhere. My request is motivated by the fact that if it uses an achromatic lens, I do not understand why no one uses the etalon block of this instrument to mount it on a large diameter telescope, just as many did with the b...
by antonello
Tue Nov 21, 2017 9:09 am
Forum: This is SolarChat !!
Topic: Lunt 50 - Single Stack / Double Stack Comparison 19th November
Replies: 22
Views: 1212

Re: Lunt 50 - Single Stack / Double Stack Comparison 19th November

Hello marktownley
Sorry, I have a curiosity: the Lunt 50 does have an achromatic lens or a single lens?
Thank you
by antonello
Fri Sep 01, 2017 5:25 am
Forum: Solar Scope Modifications
Topic: What does a "blocking filter" consist of... ?
Replies: 13
Views: 1681

Re: What does a "blocking filter" consist of... ?

Please read this my message in a italian forum:
https://www.astronomia.com/forum/showth ... RIMA-PARTE
It is in Italian language, but you should be able to understand something with google translator ...

Antonello