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...
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Gary
 
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Solar Telescope User Modifications by Mr Chia P.H.

Postby Gary » Mon Oct 22, 2012 3:14 pm

WARNING:

(1) Do NOT look directly into the Sun using naked eyes or through a telescope without proper certified solar filter(s). It will cause permanent eye damage.

(2) For those who wish to attempt the same modifications suggested here, please be 1000% sure of what you are doing and have followed the exact advise mentioned by Mr Chia. When in doubt, please contact him for clarifications.

(3) Neither Singastro nor Mr Chia will be held responsible for any damage to equipment or personal health of those who try to attempt the same modifications mentioned here.


Figure 1:
Image

Figure1--This is an Ha scope that will review a m5 and above solar flare as a bright patch or more often as a bright spot.Its modified from a thousand oak T -tuner type Ha 0.9A bandwidth filter and contains an additional of 13 filters.This system decrease the bandwidth further and enable the use of a f/5 scope which simplify the setup of the scope.You are right,Alfred,in this 13 filters there are also ethalon type filters.I dont know how to describe to you---both their spacing(and rotational angle) and distance apart are important and to be frank,after following the theory we learn,it takes a bit of trial and error to get the working arrangement.I also use the BF as a diagonal as it contain a super good light absorbing mirror inside.Another principle adapted in arranging filter is--arrange it in such a way so that each absorb a small percentage of light and so not overheat.This way we dont have to worry about cracked filters.

********************************************************

Figure 2:
Image

Figure2--this is the famous SM90.I only modify the Blocking filter and Elminate the focuser.The BF keep on dreadrusting and on the average one gone every 6 months.Thus I decided to get rid of it.During the process,I found that the BF is both getting rid or UV and IR radiation;and it also further narrow down the bandwidth of the Ha light passing through.In the end I manage to pack 10 filters plus a helical focuser and a focuser locking mechanism into the BACK of the scope to eliminate the problem of focus shift and also once and for all get rid of the dread rust problem.Also,I have control of the amt of Ha light passing through--but I choose the safest level .Again alignment is a big problem(even rotating one of the filter will ruin the whole system) and aligning those filters took at least 3 days of hard work under the hot sun!
.....to be continued.


********************************************************

Figure 3:
Image

Figure3--this is the SM40 double stacked on a firstscope 80mm refractor.The blocking filter had been completely reflaced by my 'self made' filter system.As a matter of private opinion,I think it perform slightly better than the original with BF and is slightly able to 'cut through' light' haze.

********************************************************

Figure 4:
Image

Figure 4 ----its a modified PST that had dread rusted--do you know that PST can dread rust and after dread rust,the front lens of the PST looks rusty red--not green anymore.Another SM40 front ethalon had been added to make it double stacked and filters added to cut down unwanted radiation and narrow the bandwidth.
All four instruments complement one another in operation.SM90 is for close up obs and photographing.When a suspicious brighting occurs,the flare detector--fig1---will be deployed to verify .
On the other hand,if I want to know,say,the extend of the region involved or wheather there are other 'bright' regions that single stack wont show,the double stack scope--fig3--will be setup.Finally the double stack PST will only see its service when the sun is most active.Because of its small diameter and light wt,it will serve as a '12 hour full time'monitor scope when needed.I really wish I have that during the first 6 months of this cycle24.So far thats the most active minicycle experienced.

********************************************************

Figure 5:
Image

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!

********************************************************
Figure 6:
Image

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.

********************************************************

Figure 7:
Image

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 8:
Image

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.

********************************************************

Figure 9:
Image

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.

********************************************************

Figure 10:
Image

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.
Last edited by Gary on Sat Oct 27, 2012 6:21 pm, edited 3 times in total.
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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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Re: Solar Telescope User Modifications by Mr Chia P.H.

Postby yltansg » Mon Oct 22, 2012 8:23 pm

Hi Mr Chia,

Thanks for sharing with us your setups and modifications. I thought the anchoring line to hold the EP was a great idea.

Can you share with us:

a. how to modify the blocking filter to permanently eliminate rust

b. Figure 1 (the setup to detect M5 and above flare): I see a Coronado blocking filter. Is there an etalon in the front end? What else do you need to do to detect M5 and above flare?

c. I use a Imaging source DMK camera for my imaging. Afocal sounds interesting. What do you need to do to enable afocal?

For me I am testing a software called DSSR V4 (available at http://starrydave.com/ ) to help me with time-lapse video for capturing solar flare. For this 10 second video taken on 8 Jul 12 on Sunspot 1515, https://vimeo.com/45444774 I had to make about 150 video clips of 15 second duration each. That meant I had to turn on and off the video recording 150 times - done over a period of more than 1.5 hours. And I also had to do drift compensation manually. DSSR will automate the process and also do autoguiding :) There are several challenges. I will share my findings on DSSR.

Thanks again for sharing.

Alfred

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

Postby superiorstream » Tue Oct 23, 2012 5:40 pm

Hi
Gary,--Thanks for the uploading and you are right.For years,I keep it to myself because looking at the sun can be very DANGEROUS.You can be PERMANENTLY BLINDED in less that a second!Hence I will only give a rough highlight of what I did or what the scope is capable off.Even if you have the scope and then forget to install just one of the filter/elements you can also land up blinded or you replace one of the filter with a "so called identical" one you can also land into trouble.So dont try unless you have a good knowledge of optics and also a good understanding of filters and what it is actually filtering out from the spectrum.
Now for the scopes-
Figure1--This is an Ha scope that will review a m5 and above solar flare as a bright patch or more often as a bright spot.Its modified from a thousand oak T -tuner type Ha 0.9A bandwidth filter and contains an additional of 13 filters.This system decrease the bandwidth further and enable the use of a f/5 scope which simplify the setup of the scope.You are right,Alfred,in this 13 filters there are also ethalon type filters.I dont know how to describe to you---both their spacing(and rotational angle) and distance apart are important and to be frank,after following the theory we learn,it takes a bit of trial and error to get the working arrangement.I also use the BF as a diagonal as it contain a super good light absorbing mirror inside.Another principle adapted in arranging filter is--arrange it in such a way so that each absorb a small percentage of light and so not overheat.This way we dont have to worry about cracked filters.

superiorstream
 
Posts: 1105
Joined: Mon Nov 03, 2008 4:45 pm

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

Postby superiorstream » Tue Oct 23, 2012 5:55 pm

Figure2--this is the famous SM90.I only modify the Blocking filter and Elminate the focuser.The BF keep on dreadrusting and on the average one gone every 6 months.Thus I decided to get rid of it.During the process,I found that the BF is both getting rid or UV and IR radiation;and it also further narrow down the bandwidth of the Ha light passing through.In the end I manage to pack 10 filters plus a helical focuser and a focuser locking mechanism into the BACK of the scope to eliminate the problem of focus shift and also once and for all get rid of the dread rust problem.Also,I have control of the amt of Ha light passing through--but I choose the safest level .Again alignment is a big problem(even rotating one of the filter will ruin the whole system) and aligning those filters took at least 3 days of hard work under the hot sun!
.....to be continued.

superiorstream
 
Posts: 1105
Joined: Mon Nov 03, 2008 4:45 pm

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

Postby superiorstream » Tue Oct 23, 2012 8:43 pm

Figure3--this is the SM40 double stacked on a firstscope 80mm refractor.The blocking filter had been completely reflaced by my 'self made' filter system.As a matter of private opinion,I think it perform slightly better than the original with BF and is slightly able to 'cut through' light' haze.
Figure 4 ----its a modified PST that had dread rusted--do you know that PST can dread rust and after dread rust,the front lens of the PST looks rusty red--not green anymore.Another SM40 front ethalon had been added to make it double stacked and filters added to cut down unwanted radiation and narrow the bandwidth.
All four instruments complement one another in operation.SM90 is for close up obs and photographing.When a suspicious brighting occurs,the flare detector--fig1---will be deployed to verify .
On the other hand,if I want to know,say,the extend of the region involved or wheather there are other 'bright' regions that single stack wont show,the double stack scope--fig3--will be setup.Finally the double stack PST will only see its service when the sun is most active.Because of its small diameter and light wt,it will serve as a '12 hour full time'monitor scope when needed.I really wish I have that during the first 6 months of this cycle24.So far thats the most active minicycle experienced.

superiorstream
 
Posts: 1105
Joined: Mon Nov 03, 2008 4:45 pm

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

Postby superiorstream » Tue Oct 23, 2012 9:01 pm

As for general construction,its ALL about filter stacking and physics on heat dissipation of individual filters and allowing each filter to take a safe amount of heat so that no damage occurs--that why each system has at least 5 or more filters.Also if in doubt,dont use your eye;but a camera to 'see' if its too bright.
Finally my type of photography is afocal.Nowadays,I even design my own way to attach the camera to the eyepiece to shoot.Sorry to say many of today's compact camera is NOT suitable for both Ha and CAK shooting because both these frequency are cut off.Thats why I actually use a very old compact camera to shoot--both in Ha and Cak.All my photos are unedited except for resizing and text written.
Already the amount spent on these 10 scopes is substantial.I dont want to spent more on computer software esp when they keep on changing OS-- and we keep on buying.That one of the reason I develope my own BF and these 4 scopes--to be able to do solar obs in a 'independent' way.
Next--the Cak scopes.
Last edited by superiorstream on Tue Oct 23, 2012 9:05 pm, edited 1 time in total.

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

Postby superiorstream » Tue Oct 23, 2012 9:04 pm

Hi,Alfred
Hope that answers your questions.Your questions are welcomed.Thanks.

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

Postby yltansg » Tue Oct 23, 2012 9:35 pm

Hi Mr Chia,

Thanks for answering my questions. Thanks also for alerting me about the rust problem. I am fortunate that all my 3 the blocking filters are still ok. I will make sure they stay in dry cabinet when not in use. Hope they wouldn't start rusting too soon.

Alfred

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

Postby Gary » Wed Oct 24, 2012 12:59 pm

Added figure 5, 6 and 7 in first post. CaK mods. Enjoy!
http://www.astro.sg
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.

superiorstream
 
Posts: 1105
Joined: Mon Nov 03, 2008 4:45 pm

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

Postby superiorstream » Thu Oct 25, 2012 12:20 pm

Hi,Alfred
Sorry for the late reply.Yesterday's sky is superclear starting from afternoon 12.So as usual spent the whole available clearsky time were used for testing my various gear and doing some trial and error arrangement to improve my systems.
I dont know whether your solarscope will dread rust or not,but the colorado will and useful lifespan shorten by usage--for daily user like me it show visible sign of dread rust after 1 week of use and the most most lasted only 9 months.My replacement system had worked for almost 2 years but even the construction price tag is slightly more than 1/3 the price(2008 non-offer price) of SM90 single stack.
Pls tell me if you find the solar scope 'rust'.Its always interesting to learn new things.Thanks.
Next the Cak scope---

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