Currently some great surface detail with PST Double Stack

[Mark at Beaufort]

There are some excellent filaments on the Sun at the moment.

I waited most of the day for the Sun to appear and now I have some clear slots. I fitted my recently purchased pre Meade Double Stack unit onto my PST together with a TeleVue 8-24 zoom.

The difference this DS makes to the general PST is incredible - great surface detail with the filaments standing out against the solar background. A few nice Proms and nice activity around sunspot AR2664 together with 3 smaller filaments nearby.

 

[alanjgreen]

Yep, double stacking is expensive but there is no going back. The detail is much much better.

i have never used my lunt60 in single stack mode apart from a quick look when it was new. The double stack never comes off!

[Mark at Beaufort]

3 minutes ago, alanjgreen said:

Yep, double stacking is expensive but there is no going back. The detail is much much better.

i have never used my lunt60 in single stack mode apart from a quick look when it was new. The double stack never comes off!

Yes Alan I could not believe the difference. I bought my PST in 2005 and this DS has blown the view out of the water.

[John]

Does a DS PST = a Lunt 50mm non DS in terms of performance, roughly, or is it not as straight forward as that ?

 

[michael.h.f.wilkinson]

I usually have my SolarMax-II 60 in DS mode as well, although when the skies are hazy, single stack can be better because DS takes away too much light. Didn't see the filaments today (they were awesome the last few days) due to pervasive clouds

[Mark at Beaufort]

15 minutes ago, John said:

Does a DS PST = a Lunt 50mm non DS in terms of performance, roughly, or is it not as straight forward as that ?

 

John I cannot personally answer that. I bought the DS from a SGL member who stated that at a recent star party he was able to compare the PST DS with a Lunt 50mm and the surface detail was better with the PST DS although the image was darker. I think that is what he stated from memory.

When I go solar observing I always use a purpose made black out cloth made by TH which makes viewing much better so although the view is darker it is still very good.

[alanjgreen]

37 minutes ago, Mark at Beaufort said:

John I cannot personally answer that. I bought the DS from a SGL member who stated that at a recent star party he was able to compare the PST DS with a Lunt 50mm and the surface detail was better with the PST DS although the image was darker. I think that is what he stated from memory.

When I go solar observing I always use a purpose made black out cloth made by TH which makes viewing much better so although the view is darker it is still very good.

Double stacking makes a big difference. It cannot be overstated.

I would expect a double stacked ls50 to out perform a single stack ls60. Double stack ls60 will outperform a ls80 and so on...

it wouldn't surprise me to find a double stack PST to outperform a single stack ls50. It has 45mm aperture I believe?

Reduced brightness will always be the downside of double stacking. With the smaller aperture being double stacked then darkening will be an greater issue than with double stacking a larger aperture. Stating the obvious.

proms are the first casualty of a darker image.

[John]

Thanks for those answers Alan and Mark. Very interesting

 

[Peter Drew]

A double stack PST would probably give a better contrast image than a single stack Lunt or Coronado 60mm but the 60's will have better resolution, there's no free lunch. It depends a great deal on what you want from a solar telescope, double stacking visually is going to limit you to full disc images in the main as high magnification renders the image too dim, imaging with a camera is a different situation. I prefer a larger single stack instrument that a similar outlay would provide as I like to see high magnification, high resolution performance.   

[niallk]

So... a possibly dumb question for say a LS50:

Do people ever use DS for detailed views full disc, and SS with higher mag (to combat loss of brightness) on limb/proms?

I think I hear an answer loud and clear reading forums - that 'once you double stack you never go back'

[Peter Drew]

1 hour ago, niallk said:

So... a possibly dumb question for say a LS50:

Do people ever use DS for detailed views full disc, and SS with higher mag (to combat loss of brightness) on limb/proms?

I think I hear an answer loud and clear reading forums - that 'once you double stack you never go back'

I think the answer is "yes they do". It costs nothing to remove the DS unit once you've got one and the increased brightness will allow higher magnification of the proms. Even imagers revert to single stack when necessary. 

[niallk]

Thanks Peter! I'm reading around to learn about solar setups with keen interest after being extremely impressed by my first Ha views at an event last weekend.