Which Lunt double stack filter?

[Highburymark]

This is not the first time this question's been asked (there's a thread currently on the SGL solar forum debating the same issue). But I've never really seen a definitive answer.  So I thought I'd post it again on the equipment forum. Question is this:

Is there any real benefit having a Lunt LS60 with the (white) 50mm double stack filter, over the LS50 scope with the (red) 50mm double stack filter? Of course the best set up would be the more expensive 60mm DS filter in the LS60, but how do the cheaper options compare? Does the 50mm DS filter effectively reduce your 60mm scope to a 50mm aperture one, or are there still noticeable benefits to the LS60/50mmDS package over the LS50/50mm DS (for visual observing only)? 

Anyone able to shine a little light on the subject?

 

 

 

 

[brantuk]

52 minutes ago, Highburymark said:

Does the 50mm DS filter effectively reduce your 60mm scope to a 50mm aperture one, or are there still noticeable benefits to the LS60/50mmDS package over the LS50/50mm DS (for visual observing only)?

I tried this combo and it didn't work for me so I changed for the 60mm DS. I got too many ghost images and it was too hard to determine which one you should be looking at, and the image was a smaller one than with the 60mm double stack. I don't honestly believe the 50mm DS was designed to go with the 60mm scope - it certainly didn't seem too be. And at these prices you don't want to be messing about. Hth

[Highburymark]

Ok - interesting brantuk. Wonder what the 50mm filter was developed for? It's just such a big price jump to the 60mm DS.

[Peter Drew]

I would have thought that the 50mm DS unit was developed for use in conjunction with the LS50. I've not tried a DS LS50 but would have expected it to give a better contrast than a single stack LS60. Using a 50mm DS unit on a LS60 would reduce the effective aperture to 50mm but would be the cheaper option to increase the contrast of a LS60 if you already have one. Most commercial Ha telescopes contain a small internal etalon (they've taken notice of the modders). Etalons are expensive, hence the great increase in cost for double stacking with full aperture front ones.   

[alanjgreen]

Lots of people have found the DS50 & LS60 combo underwhelming. You are cutting the aperture to 50mm so you may as well go for DS50 & LS50, results should be the same.

If you have LS60 then save for the DS60 and keep all the aperture and brightness (which is the issue with using a DS50 on the LS60)

Alan

 

[Highburymark]

What I suspected but thanks all for responding. I have a double stacked LS50 which I love. Jump up to Lunt 60/60mm DS is stratospherically expensive. Now considering a Daystar quark for use with my Equinox 80 for more detailed views - the two solar set ups should complement each other. 

[spaceboy]

I think it is worth noting that while it is possible to achieve a <1mm exit pupil with the LS60 it gets notably dim quickly. From what I have read a double stack will only go to emphasise this. If you decide to give up the 10mm aperture of the LS60SS in favour of the more affordable LS50DS then need I say more....?

[spaceboy]

And for the record I personally found the Quarks to lack contrast visually. They sure do offer up some superb images when you can process them though.

[Peter Drew]

It's been my experience that double stacking makes a black cloth or similar over the head obligatory for visual.  

[Highburymark]

3 hours ago, Peter Drew said:

It's been my experience that double stacking makes a black cloth or similar over the head obligatory for visual.  

Absolutely Peter - the cloth is no less necessary than the second etalon