14 replies to this topic

[jackk]

Hi all, wonder if anyone can help me make a decision on double stacking a lunt 60mm. I see two options, one is a 50mm and one a 60mm. The 60mm is $500 more. Anyone know how much of a difference between the two units would be? Would be doing observing plus imaging. 

These are the options I am referring to: 

https://luntsolarsys...a-solar-filter/

 

https://luntsolarsys...h-alpha-filter/

[dhkaiser]

I have seen nice results from both.  Personally I could not see me getting a 60mm solar scope and then stopping it down with a 50mm DS.  Aperture matters especially in solar observing.

[MalVeauX]

Heya,

 

It's a 20% resolution difference. It's significant.

 

Why get the 60mm just to mask it to 50mm, you know? $500 is not much when you think of the difference for the next 10+ years....

 

Very best,

[jackk]

Heya,

 

It's a 20% resolution difference. It's significant.

 

Why get the 60mm just to mask it to 50mm, you know? $500 is not much when you think of the difference for the next 10+ years....

 

Very best,

Yeah, that is kinda what I figured. I found it odd that it is even an option, so I thought perhaps there is some reason or preference I dont know about. 

[briansalomon1]

Adding a second etalon will dim the image and as a result, limit magnification. Reducing the aperture will dim the image even more.

 

It's $500 well spent.

[bigdob24]

I would go the 60mm DS and take advantage of all the aperture you can, it always rules day or night.

I think the advantage of DS out weights any dimming issues .

[rigel123]

Yeah, that is kinda what I figured. I found it odd that it is even an option, so I thought perhaps there is some reason or preference I dont know about. 

I would say it’s a marketing strategy to attract more folks to double stack that get sticker shock when seeing the price of the 60mm DS unit.  It took me 7 years to convince myself to spend the extra when I finally got it for my Lunt.

[TOMDEY]

I opted for the 60mm and was very pleases with that. Later went to double stacked 80/80. Even for Solar, Aprerture still rules!    Tom

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[vincentv]

 

Adding a second etalon will dim the image and as a result, limit magnification. Reducing the aperture will dim the image even more.

^This

If you're short on money it's possible to use a front mounted Coronado 60mm. The combination is referred to as "luntanado". You need to have an adapter machined but it works well.

 

I recon the lunt is a nicer unit, more solid construction and doesn't have the central obstruction.

[BYoesle]

 

Adding a second etalon will dim the image and as a result, limit magnification...

 

There are multiple ways to address this issue that result in a significant increase in image brightness. These are completely safe and simple modifications, but to post them would violate the CN Terms Of Service - so PM me if you are interested in these options.

[dswtan]

It really comes down to how much $500 is to you, so to speak. Especially compared to what you have already invested. Solar is expensive!

 

Context: I started with the 50 DS before upgrading to the 60 DS on my LS60T. I'm on the fence as to whether it was "worth it", but at the time, I could afford the $500 extra. A facto to consider is that there seems to be a fairly healthy resale value in these DS units (50s anyway, because of people eventually upgrading?), so if you don't mind the hassle, you can recoup most of the costs either way. 

[briansalomon1]

^This

If you're short on money it's possible to use a front mounted Coronado 60mm. The combination is referred to as "luntanado". You need to have an adapter machined but it works well.

 

I recon the lunt is a nicer unit, more solid construction and doesn't have the central obstruction.

I keep an eye on local DS etalons for sale and don't mind adding an adapter if I find a good Coronado unit.

[Zyx]

It is a little crazy that for the cost of just the Lunt 60mm double stack filter, you could buy a Lunt 50mm double-stacked scope.

[bob71741]

jackk - The reason that a 50 mm DS option exists is because in the early Lunt days they offered a 60 mm double pass solar telescope that people bought, but Lunt was not able to get it into production. Lunt was also making 50 mm etalons for their 100 mm telescope, so they offered a 50mm DS etalon to go along with the 60mm scope to make their obligation to ship a 60 mm double pass telescope. Until they could make 60mm etalons, which was a long time, they kept the 50mm option available.

[briansalomon1]

jackk - The reason that a 50 mm DS option exists is because in the early Lunt days they offered a 60 mm double pass solar telescope that people bought, but Lunt was not able to get it into production. Lunt was also making 50 mm etalons for their 100 mm telescope, so they offered a 50mm DS etalon to go along with the 60mm scope to make their obligation to ship a 60 mm double pass telescope. Until they could make 60mm etalons, which was a long time, they kept the 50mm option available.

So the 50mm etalons were installed further back in the light cone of the 100mm telescope?