130GTX as a solar scope


Chris White
 

Is it safe to use a 130GTX as a solar scope?  I've seen that some people get a Quark Daystar for their scopes.  I'm wondering if this is safe to do with the 130GTX or if there is risk in damaging the coatings or anything else? 

If it is safe to do, what are people using for converting their scope to a solar scope? 

I've had a ton of wonderful bluebird days this summer, and absolutely no clear nights.  Itching to do some imaging!


David
 

Perfectly safe.  Use my 130GT for this all the time.  Daystar recommends using a front sided energy rejection filter for anything over 80mm.  They sell these. Then use your Quark or Quantum at the rear.  Works great.


David



On Jul 11, 2021, at 5:47 PM, Chris White <chris.white@...> wrote:

Is it safe to use a 130GTX as a solar scope?  I've seen that some people get a Quark Daystar for their scopes.  I'm wondering if this is safe to do with the 130GTX or if there is risk in damaging the coatings or anything else? 

If it is safe to do, what are people using for converting their scope to a solar scope? 

I've had a ton of wonderful bluebird days this summer, and absolutely no clear nights.  Itching to do some imaging!


Chris White
 

Thanks David. Appreciate the link!  Pretty pricey once you combine the quark and the filter.  Almost makes sense to just get a dedicated solar scope although the longer FL with the quark let's you get so much closer for roi work.  


dang.astro
 

Hello,

I've been using my GTX for quite a bit of solar. I would recommend a front mounted ERF for Ha work if your serious. If anything, for insurance on an irreplaceable scope like these. I do not use any ERF for white light imaging with the Baader wedge as most of heat escapes through the diagonal. Really, the ERF is to protect the Ha filter itself not the scope. There is no focused light in the front lens so heat doesn't build. On larger than 150mm aperture scopes an ERF is needed so the focused beam doesn't crack the filter (again, not the scope). A sub aperture ERF like a uv/ir block filter is really all that's needed in front of the quark. My astrobin has images with the GTX: https://www.astrobin.com/users/Dan.Goelling/

Hope this helps,
Dan


Christopher Erickson
 

I have a bunch of solar filters, including a Quark and a Coronado 90. Both work just fine on the 130.

The Quark reflects over 99% of the incoming light right back out of the front of the scope. The OTA does not get hot.

Having said that, the Quark can't compete with the views through my Coronado 90. At about 1/5 the price, this isn't surprising. For the price, the Quark is a great h-alpha filter.

-Christopher Erickson
Observatory engineer
Waikoloa, HI 96738
www.summitkinetics.com
   


On Wed, Jul 14, 2021, 4:56 AM dang.astro <dragracingdan@...> wrote:
Hello,

I've been using my GTX for quite a bit of solar. I would recommend a front mounted ERF for Ha work if your serious. If anything, for insurance on an irreplaceable scope like these. I do not use any ERF for white light imaging with the Baader wedge as most of heat escapes through the diagonal. Really, the ERF is to protect the Ha filter itself not the scope. There is no focused light in the front lens so heat doesn't build. On larger than 150mm aperture scopes an ERF is needed so the focused beam doesn't crack the filter (again, not the scope). A sub aperture ERF like a uv/ir block filter is really all that's needed in front of the quark. My astrobin has images with the GTX: https://www.astrobin.com/users/Dan.Goelling/

Hope this helps,
Dan


Shawn Quinn
 

Folks,

I’m glad to see this thread.  I’ve been contemplating a number of options for solar imaging using the Mach 2 and perhaps the Stowaway including:

1. Stowaway + Daystar Quantum SE
2. Stowaway + Coronado Solarmax 90 filter
3. A dedicated Solar Scope from Lunt or Coronado

My initial lean was #1.  I like the idea of a dual use Stowaway leveraging the awesome Astro-Physics optics.  Additionally, I hope to one day acquire a 130GTX and I could use the Quantum SE with that as well.  

The costs of the filters are on the same order of magnitude as a dedicated solar scope.  So I’m a bit conflicted.  The ability to acquire high quality images is my highest figure of merit.  


Your thoughts will be appreciated.

Shawn


Chris White
 

On Wed, Jul 14, 2021 at 07:56 AM, dang.astro wrote:
If anything, for insurance on an irreplaceable scope like these.
Sounds like it is totally safe and doable to use a GTX for solar imaging, but this comment from Dan really hits home for me.  It took a while for me to get my hands on a GTX, and to be able to use it with something like a Quark and a rejection filer on the front the cost is getting upwards of a nice 60mm or even 80mm (second hand) dedicated solar scope.  The fact that the GTX is pretty irreplaceable made me decide to only use it at night.  I know this is a little bit of an overreaction, but I'm ok with that.  lol


Frost David
 

Keep you eye out on Astromart and other forums for used stuff.  I found a Quantum SE 0.4 for a good bit less than half price there.  It’s amazing.

David



On Jul 15, 2021, at 12:20 PM, Shawn Quinn <quinnfamily@...> wrote:



Folks,

I’m glad to see this thread.  I’ve been contemplating a number of options for solar imaging using the Mach 2 and perhaps the Stowaway including:

1. Stowaway + Daystar Quantum SE
2. Stowaway + Coronado Solarmax 90 filter
3. A dedicated Solar Scope from Lunt or Coronado

My initial lean was #1.  I like the idea of a dual use Stowaway leveraging the awesome Astro-Physics optics.  Additionally, I hope to one day acquire a 130GTX and I could use the Quantum SE with that as well.  

The costs of the filters are on the same order of magnitude as a dedicated solar scope.  So I’m a bit conflicted.  The ability to acquire high quality images is my highest figure of merit.  


Your thoughts will be appreciated.

Shawn


Shawn Quinn
 

Thanks David, good to know you’re pleased with its performance.  Shawn 


Christopher Erickson
 

A Coronado 90 plus Stowaway is an AWESOME combination.

"My advice is always free and worth every penny!"

-Christopher Erickson
Observatory Engineer
Summit Kinetics
Waikoloa, Hawaii


On Thu, Jul 15, 2021 at 1:57 PM Frost David <frosty5@...> wrote:
Keep you eye out on Astromart and other forums for used stuff.  I found a Quantum SE 0.4 for a good bit less than half price there.  It’s amazing.

David



On Jul 15, 2021, at 12:20 PM, Shawn Quinn <quinnfamily@...> wrote:



Folks,

I’m glad to see this thread.  I’ve been contemplating a number of options for solar imaging using the Mach 2 and perhaps the Stowaway including:

1. Stowaway + Daystar Quantum SE
2. Stowaway + Coronado Solarmax 90 filter
3. A dedicated Solar Scope from Lunt or Coronado

My initial lean was #1.  I like the idea of a dual use Stowaway leveraging the awesome Astro-Physics optics.  Additionally, I hope to one day acquire a 130GTX and I could use the Quantum SE with that as well.  

The costs of the filters are on the same order of magnitude as a dedicated solar scope.  So I’m a bit conflicted.  The ability to acquire high quality images is my highest figure of merit.  


Your thoughts will be appreciated.

Shawn


Shawn Quinn
 

Thanks Chris!

Shawn