Lunt Solar Scopes

luntsolarsystems.com/ls200t_dp_ha.html

And it's cheaper than a 90mm Coronado filter.

I pulled the trigger a couple of days ago and asked for details of the LS50 filter for my William Optics 66mm for an ultraportable setup. Should give a better image than the PST (I think my PST is also around .75A - .8A). Still haven't heard back from Teton yet though.

Does anyone know if the double-stack etalons need to be matched to your filter like with the Coronado system?

Trev

You may be asked to talk to Markus Ludus of APM seen as you are in Europe.

Ah I see, thanks for that Michael. I hadn't noticed they were distributing in Europe.

I'm going to hold off and maybe think about the 75mm or a Solar Spectrum in a year or so.

Trev

Trev,

Solar Spectrum have only two dealers that I am aware of: Baader in Europe and Alpine Astro in the US. Price difference was simply extraordinary. I wanted to buy a Solar Spectrum filter from Alpine Astro last year but was refused a sale once they realised I was in Europe. The price difference was so large, that it would easily have paid me to cover all courier, tax and duty fees and still have a large wad of cash in my back pocket. So, I simply had to give up on the idea as I could not justify paying the extra premium for the filter in Europe. Apparently, the lead time on the Solar Spectrum filters is approx 1 year.

If you were considering the purchase of a rear-mounted filter, I'd recommend taking a serious look at the Daystar ones. www.daystarfilters.com/
like all solar filters, they are expensive. However, you can deal directly with the manufacturer no problem. With these systems, you can get narrower bandpasses than front-mounted filters double-stacked and can use it on different size scopes. They also have entire h-alpha systems: www.icstars.com/index.htm

The one real highlight of Lunt's products is the 8" double-stacked unit. With this unit, you have an entire h-alpha telescope with decent aperture and a narrow bandpass (0.55A) in one system. The cost of this entire unit is approx the same price as a single 100mm filter of 0.7A. Unless there is something seriously flawed with the design of the 8" system, it's selling for a fantastic price when compared to the other front-mounted filters. I'm curious to know how they can get 8" of light through a single 60mm diameter filter TWICE to double-stack it. My guess is some sort of folded newtonian, but I could be wrong.

I see our buddy Patrick at Telescope Service is a dealer for Lunt Solar Systems now. www.teleskop-service.de/Lunt_Solar/LUNT.htm

Regards,

That's excellent news! The reason I was leaning towards solar spectrum was that Patrick is also a dealer for them so there would be good support & it was cheaper than the Daystar is in Europe.

I just remembered why I discounted the Daystar system (the .6A T-scanner). It requires an f30 beam or more. So no way to get whole disc shots. I guess that means I can't do this with solar spectrum either as I just noticed it requires a telecentric module attached.

I think that's it - it looks like the Lunt offering for me, but I'll probably stick to a 50mm or 75mm so that I can have a grab'n'go.

The only problem is that if I purchase one of these is that it means at least 3 months of cloudy skies for the rest of ye!!!!!

All the filters require parallel or near parallel rays. On the front mounted filter, this is obviously no prob. On a filter mounted internally, it needs a telecentric lens or a barlow.
Baader make these telecentric lenses (see bottom of page): www.solarspectrumfilter.de/
and here: www.sungazer.net/tele.html
and here: www.alpineastro.com/Reference_Docs/Telecentric%20System.pdf

From looking at the last url, it appears to me at least, that the equivalent focal length of the system is only increased by approx 250mm, so the magnification and FOV shouldn't change substantially.