The Charlie Bates Solar Astronomy Project is proudly sponsored by the following fine companies:
ImageImageImageImage
Image
Image
Transit of Mercury in the Spicule Layer. Phil took this great image with his Quantum 6 Scope, Solar Spectrum etalon and PGR Camera.

Welcome to Solar Chat! The best forum for Solar Astronomy
Moving forward from solar cycle 24 to 25

SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

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
Solarhound
Ohhhhhh My!
Ohhhhhh My!
Posts: 132
Joined: Sun Jul 28, 2013 4:51 pm

SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Solarhound » Sat Dec 07, 2013 4:52 pm

Hello solar friends .

After successfully modding my PST I had the idea of trying to apply a similar mod to my SM 60 to try to take advantage of the larger etalon . The SM 60 is F 6.6 and the donor scope I used (Apogee 127) is F 6.5 I thought that the 0.1 difference in F ratio would not be an issue but it will not focus sharply . It could be the miss match in F ratio's or possibly cheap optics on the Apogee or I am open to your suggestions . Here is a description of the mod .

This first image shows the 2 scopes side by side with F ratio templates .




Next I made a cap for the end of the 127 with a PVC sleeve to protect the tube of the SM 60 and 3 set screws to lock the sm 60 into place .




Then I installed a 100mm Lunt ERF at the 100mm light cone position




And this is the SM 60 with objective removed and installed into the 127 Apogee




I have not had the weather for much testing but am having trouble obtaining a sharp focus , Any suggestions would be most welcome , Thank you

Here are a couple of first images from this scope







Attached files

User avatar
marktownley
Librarian
Librarian
Posts: 26449
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by marktownley » Sat Dec 07, 2013 5:34 pm

looks a good mod, not sure why you are getting the focus issues you are, it does look rather soft - maybe poor seeing? . At 130mm aperture you will only be able to use this on the steadiest days.

Looks like you are post processing your images in 8 bit too, they seem quite noisy for a DMK camera.
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!

Solarhound
Ohhhhhh My!
Ohhhhhh My!
Posts: 132
Joined: Sun Jul 28, 2013 4:51 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Solarhound » Sat Dec 07, 2013 5:49 pm

Thank you Mark , it very well could have been poor conditions , I have only had a couple of opportunities to try this one . I do remember having to lower the gamma to levels I no not normally go to to bring up some contrast .I will need a better day for more testing .
I have used much of the information you have provided for my mods , Thank you Mark .

User avatar
swisswalter
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 17951
Joined: Thu Feb 06, 2014 4:28 am
Location: Switzerland
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by swisswalter » Mon Dec 09, 2013 9:28 am

Hi Steve

that is a good start. I wish you good seeing conditions to test the moded 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 ;)

peter drew
Im an EXPERT!
Im an EXPERT!
Posts: 263
Joined: Sat Feb 04, 2012 6:18 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by peter drew » Mon Dec 09, 2013 10:17 am

Isn't the SM60 an external etalon?, if so doesn't it need parallel light to operate properly rather than a F6.5 beam?

Solarhound
Ohhhhhh My!
Ohhhhhh My!
Posts: 132
Joined: Sun Jul 28, 2013 4:51 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Solarhound » Mon Dec 09, 2013 11:03 pm

Sorry I should have been more specific , my scope is a SM 60 II . The single stack version uses an internal etalon similar to the PST only larger and configured to F 6.6 . Double stacking adds a full aperture etalon to the front of the scope .

User avatar
Merlin66
Librarian
Librarian
Posts: 3369
Joined: Tue Dec 13, 2011 1:23 pm
Location: St Leonards, Australia
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Merlin66 » Tue Dec 10, 2013 5:20 am

Yes,
The "new" generation SM60II...just like a 60mm PST -with attitude!
"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
swisswalter
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 17951
Joined: Thu Feb 06, 2014 4:28 am
Location: Switzerland
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by swisswalter » Tue Dec 10, 2013 3:50 pm

Yes,
The "new" generation SM60II...just like a 60mm PST -with attitude!

:)
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 ;)

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3350
Joined: Sun Nov 18, 2012 3:13 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Valery » Tue Dec 10, 2013 6:25 pm

looks a good mod, not sure why you are getting the focus issues you are, it does look rather soft - maybe poor seeing? . At 130mm aperture you will only be able to use this on the steadiest days.

Looks like you are post processing your images in 8 bit too, they seem quite noisy for a DMK camera.

The softness can be due one of these reasons or combination of them

1. Donor objective has only one parameter practically identical to the one in the native objective - the F/D
All other can be (and really are) quite different, especially spherical aberration, field curvature astigmatism etc.

2. Poor focusing.

3. Poor seeing.
"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
swisswalter
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 17951
Joined: Thu Feb 06, 2014 4:28 am
Location: Switzerland
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by swisswalter » Tue Dec 10, 2013 6:35 pm

Hi Valery

on that level I exclude "poor focusing". Leaves us poor seeing and optical issues
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 ;)

User avatar
marktownley
Librarian
Librarian
Posts: 26449
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by marktownley » Tue Dec 10, 2013 9:47 pm

Donor objective has only one parameter practically identical to the one in the native objective - the F/D
All other can be (and really are) quite different, especially spherical aberration, field curvature astigmatism etc.

Having swapped the same etalon around several scopes (on my pst mods) these factors all vary quite significantly from scope to scope...
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
Merlin66
Librarian
Librarian
Posts: 3369
Joined: Tue Dec 13, 2011 1:23 pm
Location: St Leonards, Australia
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Merlin66 » Tue Dec 10, 2013 11:01 pm

Hmmm
I agree there are some differences, but not such as to significantly impact on the performance of the PST etalon...
The vast majority of PST mods have been very successful when applied to basic achromats with an f ratio close to f10. I find the quality of the etalon, alignment, and positioning to be the key parameters to success.
"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

peter drew
Im an EXPERT!
Im an EXPERT!
Posts: 263
Joined: Sat Feb 04, 2012 6:18 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by peter drew » Tue Dec 10, 2013 11:26 pm

+1 Ken, this has also been my experience. I have five PST etalons and there is a difference in their performance when applied to the same donor telescope.

Solarhound
Ohhhhhh My!
Ohhhhhh My!
Posts: 132
Joined: Sun Jul 28, 2013 4:51 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Solarhound » Wed Dec 11, 2013 1:44 am

I will need a day when conditions are good so I can rule out the atmosphere . It could be an optical miss match , it comes very close but not quite crisp and sharp .
Mark I would be interested to know which donor scope gave you the best results .I am very happy with my PST / 102 XLT mod and was expecting better results with the SM 60 II / 127 Apogee , so far not the case .

Thank you for all the interesting answers and input to my question .

User avatar
marktownley
Librarian
Librarian
Posts: 26449
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by marktownley » Wed Dec 11, 2013 6:48 am

+1 Ken, this has also been my experience. I have five PST etalons and there is a difference in their performance when applied to the same donor telescope.

I should also add that the 3 pst etalons I have used also give different results too like Peter has found....
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
marktownley
Librarian
Librarian
Posts: 26449
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by marktownley » Wed Dec 11, 2013 6:52 am

I will need a day when conditions are good so I can rule out the atmosphere . It could be an optical miss match , it comes very close but not quite crisp and sharp .
Mark I would be interested to know which donor scope gave you the best results .I am very happy with my PST / 102 XLT mod and was expecting better results with the SM 60 II / 127 Apogee , so far not the case .

Thank you for all the interesting answers and input to my question .

My 100mm Tal100R refractor works the best optically out of the scopes I have tried.

Do you have the stacked raw file we can take a look at - no sharpening, wavelets etc.
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!

Solarhound
Ohhhhhh My!
Ohhhhhh My!
Posts: 132
Joined: Sun Jul 28, 2013 4:51 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Solarhound » Wed Dec 11, 2013 4:44 pm

Sorry Mark but I deleted the videos , all I have is the tiff's after registax 6.1 adjustments .


[attachment:1]t1 127.tif[/attachment]


[attachment:2]t3 127.tif[/attachment]

The gamma was reduced more than I would normally go , down around 45 if I remember correctly , these were done back in mid November .

Thank you everyone for your help

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3350
Joined: Sun Nov 18, 2012 3:13 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Valery » Wed Dec 11, 2013 6:05 pm

Hmmm
I agree there are some differences, but not such as to significantly impact on the performance of the PST etalon...
The vast majority of PST mods have been very successful when applied to basic achromats with an f ratio close to f10. I find the quality of the etalon, alignment, and positioning to be the key parameters to success.

PST has a good reputation for the mods due several reasons:

1. It's native F/ratio is quite slow - F/10. This narrow cone can and really does, "stops" faster donor optics to F/10.
2. F/10 is good for blocking filter work (less energy from nearest peaks of etalon transmission).
3. The optics of the collimator is designed for corrected F/10 achromat. So, all telescopes will work with this optics at F/10
just fine.

OTOH, the collimator and refocusing optics in the telescopes with native SINGLET objective will NOT work well with ANY another donor objective. Because this optics is designed to work with a given singlet and it corrects all the aberrations of this singlet (SA, astigmatism, field curvature).
Etalons and relative optics from all telescopes, designed as "straight through" with a singlets is not suitable for mods with just replacing the donor objective.

On a final note. I think some of you seen my earliest and latest sun images with mods of SW150mm + LS50F Ha + aries kit of optics. They are quite different in the sharpness and contrast of the smallest finest details. The reason is not my experience in the photography - it is basically the same. The difference is because the latest optics is made from exactly as were designed. In the first trial optics the laboratory where I placed the order for the prototype, took a mistake mixturing one of the glass type in the collimator triplet. Hence the SA. I corrected is as I can with the SAFIX, but not fix it completely. And this residual SA softens the details quite significantly and to extract details of the final images I was need to over process them. Now I can process the images without too much deconvolution steps and obtain a wealth of finest details.
So, it is quite important to have SA fixed or at very minimal level if you like to have good detailed pictures. This is possible only if your optics is designed to work with corrected doublets (like PST) or similar, not from the scopes with a singlet objectives.

Hope this helps.


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
marktownley
Librarian
Librarian
Posts: 26449
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by marktownley » Wed Dec 11, 2013 9:40 pm

Your work with the 150 mod you've been doing is excellent Valery. Do you think there is a better option for the collimator lens that is used in the PST etalon assembly for when it is used in a PST mod?
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
swisswalter
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 17951
Joined: Thu Feb 06, 2014 4:28 am
Location: Switzerland
Contact:

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by swisswalter » Wed Dec 11, 2013 11:25 pm

PST has a good reputation for the mods due several reasons:

1. It's native F/ratio is quite slow - F/10. This narrow cone can and really does, "stops" faster donor optics to F/10.
2. F/10 is good for blocking filter work (less energy from nearest peaks of etalon transmission).
3. The optics of the collimator is designed for corrected F/10 achromat. So, all telescopes will work with this optics at F/10
just fine.

OTOH, the collimator and refocusing optics in the telescopes with native SINGLET objective will NOT work well with ANY another donor objective. Because this optics is designed to work with a given singlet and it corrects all the aberrations of this singlet (SA, astigmatism, field curvature).
Etalons and relative optics from all telescopes, designed as "straight through" with a singlets is not suitable for mods with just replacing the donor objective.

On a final note. I think some of you seen my earliest and latest sun images with mods of SW150mm + LS50F Ha + aries kit of optics. They are quite different in the sharpness and contrast of the smallest finest details. The reason is not my experience in the photography - it is basically the same. The difference is because the latest optics is made from exactly as were designed. In the first trial optics the laboratory where I placed the order for the prototype, took a mistake mixturing one of the glass type in the collimator triplet. Hence the SA. I corrected is as I can with the SAFIX, but not fix it completely. And this residual SA softens the details quite significantly and to extract details of the final images I was need to over process them. Now I can process the images without too much deconvolution steps and obtain a wealth of finest details.
So, it is quite important to have SA fixed or at very minimal level if you like to have good detailed pictures. This is possible only if your optics is designed to work with corrected doublets (like PST) or similar, not from the scopes with a singlet objectives.

Hope this helps.


Valery


Hi Valery

thank you very much for that insight and the information
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 ;)

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3350
Joined: Sun Nov 18, 2012 3:13 pm

Re: SM 60 with 127mm F6.5 mod , Anyone try anything like this ?

Post by Valery » Thu Dec 12, 2013 2:56 am

Your work with the 150 mod you've been doing is excellent Valery. Do you think there is a better option for the collimator lens that is used in the PST etalon assembly for when it is used in a PST mod?

I think not. In the PST rig (collimator - etalon - refocuser) design there is no room for any significant improvements.
"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.

Post Reply