Solar Telescope User Modifications by Mr Chia P.H.

Wanna make a scope? Or better still, grind a mirror yourself. Or, you have some good tips in making a really useful accessory? This is the place to show what your hands can do...
superiorstream
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by superiorstream »

Figure 5 is my main Cak scope.Its actually a lunt Cak 2.2A bandwidth with the scope replaced by a Teleview Pronto.Not much changes other than afocal enabled so that both life-viewing and photography become possible(as you may know most people--including myself--cant see a thing in Cak light).Note the selection of scope in this case.I discover that NOT ALL telescope objective are transparent to Cak;and sometimes you may find that some are semitransparent or even opaque to Cak.Also how the camera react to it is important and common sense will tell you that.Which auto focus camera will be design to focus on BLUE light?So to find a scope camera combination that works takes quite some testing under hot sunshine!
superiorstream
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by superiorstream »

Figure 7 is a Cak PST modified by a larger objective to provide an larger and brighter image.Again,the most tedious part is to find a good quality lens thats transparent to Cak;another is the mounting of the lens.Its main use will be for continuous viewing of the sun during 'continuous' flaring periods.The ease of taking it into the house means that it can be use till the first drop of rainfall(similar to my Ha double stack PST).
Figure 6 is a Cak scope(aperture 90mm) with a wider bandwidth to encompass the CaH line.It can be considered self constructed self-assembled.It consisted of 8 filters(some ethalon type),some stacked in tilted manner to provide the required image location.(those who had worked with ethalon type filter will understand and also that such filters are rotation sensitive!)Quite some time had been put --in trial and error--to get the best location and orientation for best image quality and of course those time spent to get this arrangement were under the HOT sun!The view obtained is similar to the PST's but size and shape of HOTSPOT slightly different.
Next--the white light and 540nm scopes.
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Gary
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by Gary »

Added Figure 8, 9 and 10 in first post. White light mods. Enjoy!
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email: gary[at]astro.sg
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"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.
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yltansg
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Favourite scope: Borg 76 + Solar Scope SF50
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by yltansg »

Hi Mr Chia,

I have the Solar Scope SF50 etalon with Blocking filter on a Borg 76mm since Jan 2011. It is my most frequently used scope. I keep it in a cupboard with an filament lamp when not in used. The BF seems to be holding out. I bought it second hand and the previous owner had it for 5 years.

Base on your sharing, I feel that the Coronado SM 90 is the one that will give me the rust problem. I had it for 4 months now. It is a pre-Meade scope and must have been around for at least 4 years. For this scope I keep the BF in a Digi-Cabi dry cabinet.Yes, I will let you know when I see rust.

Alfred
superiorstream
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by superiorstream »

Hi
Gary--Thanks for the upload.This journey will not be possible without your good work.Thanks again.
Alfred--I dont know about the SF scope,but as for coronado,its happens to all my BF.To see it,--the dread rust--you MUST put the end facing the scope under sunlight.You will see a BROWNISH RED ring GROWING towards the centre of the filter by the day.If the centre Greenish portion is totally covered,then your BF has completely dread rust.The image you see through the scope then will be too dim and no visual is now possible.Our tropical moist climate is the biggest cause of the rust.;but of course,its speed up with usage.
Now for the scope-
Figure 10-is an normal 100mm refractor on a thousand-oak type 2 filter.The light is then filtered to narrowed somewhat by about 5 filters so that while preserving the view of 'yellow' the quality of the image is slightly enhanced.It produce the 'best image" under normal viewing condition under wide bandwidth.
Figure 9--is a normal 80mm refractor under a system of filters--12 at least--to produce a view of the sun at 540nm narrowband.Various other narrowband--eg oxggen3; Ha at 7 to 10nm;etc had been tested and its found experimentally that this give the most contrasting view both visually and for photography.Its ease to be set up,move around make this one of the most used scope.
superiorstream
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by superiorstream »

Figure 8--this is the Celestron OMNI used as a solar scope.A special filter had been installed in the OTA to cater for absorbing the excess sunlight entering.Together,it consist of 14 to 16 filters to narrow,dim the sunlight to a safe level at 540nm while also cutting down the UV,IR to a safe level.Its use is to zoom into the various sunspots in the events of events like flares,etc.
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Gary
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Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by Gary »

I have added the individual figure descriptions in the first post so readers do not need to waste time scrolling up and down and paging left and right. Enjoy! :)
http://www.astro.sg
email: gary[at]astro.sg
twitter: @astrosg


"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.
superiorstream
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Joined: Mon Nov 03, 2008 4:45 pm

Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by superiorstream »

Hi,All
This solar journey had been a long one.Its started in around 1980 with a 40mm solar scope whose objective is just a 40mm plano-convex thin lens and filters inside a adjustible length vacuum cleaner tube on a 0.965 eyepiece of various focal length.
Later after 1985,another scope with the same concept of filtering was built--now with a 60mm achromatic objective and(varioue eyepieces) the most powerful eyepiece is an oil immersion microscope objective.
These two scope were kept till today for sentimental value.(if you want I can post photos of these 2 primative scopes).
In 1995,the FL102s with thousand oak filter-type2--starts providing an even better view of the solar details in white light and by 2002 I started using this scope and another--C6R refractor on a 6 ins full aperture f/8 to view the sun.Solar photography (digital)also started that year with my own self design afocal bracket.The rest is history.
Thus for the beginner,the thousandoak filter provide a good starting path to get the experiences.
Also I had numerously tried other frequencies to try to get a better view.So if you have discovered
say another frequency that can say provide an even better view than the 540nm say ,do let me know.Thanks.
superiorstream
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Joined: Mon Nov 03, 2008 4:45 pm

Re: Solar Telescope User Modifications by Mr Chia P.H.

Post by superiorstream »

Hi,All
Finally thanks all those who had sole equipment to me.Of the 10 scopes,only 3 were bought new--7 were bought from fellow friends in singastro.So,special thanks to-rlow,kkk26,ron,arief,harlequin,Chee yuin,croy,MooEy,denebman,mrngbss,etc and ALL the astro-vendors in Singapore.Many tests would have not been possible without those scopes,filters,and eyepieces from them.Thanks again and hope your solar journey will be a wonderful one.Remember--safety first in solar viewing.
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