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Bender

80ed with daystar quark or Lunt 60 for visual

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Not sure if I should post this here or in the solar forum.

Having a basic Lunt 60 b1200 on order I now wonder what the benefit of a Quark eyepiece (chromosphere version ?) coupled with my 80ed for visual on a small alt az mount would be .(considering the longer fl of my 100ed it might push magnification with the 4,2 quark barlow to much)

I used to have a solarmax 60 II (400mm fl) and never went below a 11 or sometimes 9mm ep.

With the 4.2 factor even a 40mm plossl in a 80ed would translate into a 7mm equivalent in the sm60.

One plus side for the lunt is the ability to use a binoviewer. Combining the quark 4.2 magnification with a Binoviewer barlow wouldn't be very useful..

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The ED80/Quark setup would give you a more detailed and closer up view of the solar activity than the 60mm Lunt. I have used this system with binoviewers and 25mm and 32mm eyepieces, in suitable conditions the views are stunning.  :smiley:

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You wouldn't be using the binoviewer Barlow as well as the Quark telecentric lens. The lens in the quark will provide plenty of focus for your bino, which is the only reason bino's typically need a Barlow in a refractor telescope.

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That sounds encouraging :)

I only have a t2 prism diagonal. Will this be ok or is a mirror diagonal recommended.

To keep the focal lenght down for visual observation, I could try a focal reducer for my 80ed, or for the same money get a Startravel f5 100mm instead. Both giving 500mm fl. I read someone warning of using fast achros because they are optimised for green light. Would I still see better details with a st100 vs my 80ed plus 0.85x fr ?

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That sounds encouraging :)

I only have a t2 prism diagonal. Will this be ok or is a mirror diagonal recommended.

To keep the focal lenght down for visual observation, I could try a focal reducer for my 80ed, or for the same money get a Startravel f5 100mm instead. Both giving 500mm fl. I read someone warning of using fast achros because they are optimised for green light. Would I still see better details with a st100 vs my 80ed plus 0.85x fr ?

Hi Andre,

I use a Zeiss T2 prism for the Quark with no problems, it works well.

With my TV85 I often use an Orion x0.8 focal reducer which just about gives full disk views and is very nice with either 32mm Plossl or 25mm Ortho

We tried my Quark in Nick's ST102 and the views were not that good, I don't know why. Although in theory an achro should be fine, I think fast achros are not so good and slow achros just give too much power. The 80ED is an excellent choice I think, although from Shaun's experience an 80 Esprit would be even better!! Bit pricey though ;-)

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Thanks Stu. I guess the SW reducer is the same ? Sorry, never used a reducer before, do I simply screw it on the end of the 80ed focuser tube, then attach my 2" Clicklock clamp and put the diagonal in there?

Edited by Bender

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Doesn't the reducer get hot, or is it far enough in advance of the focal point that it doesn't matter? Or is there a D-ERF, etc?

Russell

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Thanks Stu. I guess the SW reducer is the same ? Sorry, never used a reducer before, do I simply screw it on the end of the 80ed focuser tube, then attach my 2" Clicklock clamp and put the diagonal in there?

I'm not totally sure how the SW one works Andre.

The Orion one has a 2" barrel plus a T2 thread on the eyepiece side.

To answers Russ's question at the same time, I screw the UV/IR cut into the barrel of the reducer so it is protected, a Clicklock 2" adaptor screws to the T2 thread and this takes the diagonal. I'll post a picture in a little while

EDIT I've actually taken to putting the quark ahead of the diagonal as it helped with achieving focus, I guess because of its position relative to the reducer

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Andre,

The 80 ED is the same as my Equinox I believe, the views are quite stunning if I am honest. The Esprit is very good and also gives a full disc even with a 25mm eyepiece. But as Stu mentions there are much cheaper ways to achieve a full disc.... I just love the shorty fracs :smiley: In comparison there is also a positive stepped change from what the Lunt 60 delivers ... you wouldn't be disappointed.

Edited by Pig
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This is the arrangement I use quite frequently in everything apart from the Tak 60. From bottom to top in the picture:

Baader UV/IR Cut Filter

Orion x0.8 Reducer

T2 to 2" adapter (I lied about the Clicklock, that's on another prism)

Quark Chromosphere

Zeiss T2 Prism

Televue 32mm Plossl with eyeguard extender

c903e4b5301a7ae8dd186d130cc9d2f2.jpg

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That's interesting and a shame about the ST102, Stu. I have come to the conclusion that something is not quite right about the Quark in my Tele Vue 60. The view is okay, fine, nice, and I was thinking because it's a touch faster than my biggest scopes, that's why the contrast is a bit lower.

But I got a nice session in this morning with my 120 and there is a fair gulf in contrast compared with the TV60 of late, more than I would expect for a straight forward difference in speed, and I know the TV60 is good optically, it takes mag really well and is very sharp.

So I am wondering whether my Quark is not quite lined up with the optical axis, which I believe can widen the bandpass and lower the performance/contrast. So I am thinking of going straight through for imaging and maybe seeing if I can get diagonal after Quark for observing.

Or just buy an Esprit 80 :grin:

We tried my Quark in Nick's ST102 and the views were not that good, I don't know why. Although in theory an achro should be fine, I think fast achros are not so good and slow achros just give too much power. The 80ED is an excellent choice I think, although from Shaun's experience an 80 Esprit would be even better!! Bit pricey though ;-)

Edited by Luke

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Luke,

If its any consolation my Esprit was not as contrasty on the surface detail today as the Equinox, The proms were still better in the Esprit.

Don't get me wrong the views were still excellent and maybe I am being a little picky, it might be that I need to be more selective when tuning.

Mind you I did swap diagonals betwixt the 2 last night and this could be the cause.... I will try it out ... its not an aperture thing as both of mine are 80mm

Edited by Pig
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This is the arrangement I use quite frequently in everything apart from the Tak 60. From bottom to top in the picture:

Baader UV/IR Cut Filter

Orion x0.8 Reducer

T2 to 2" adapter (I lied about the Clicklock, that's on another prism)

Quark Chromosphere

Zeiss T2 Prism

Televue 32mm Plossl with eyeguard extender

c903e4b5301a7ae8dd186d130cc9d2f2.jpg

Thanks for the picture Stu, the setup is bigger then my 80ed :)

I think I place an order for a quark and then see how it goes.

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Thanks for the picture Stu, the setup is bigger then my 80ed :)

I think I place an order for a quark and then see how it goes.

It is a little long Andre but actually in some ways it's better than having the Quark plus eyepiece sticking up from the diagonal. It might also help keep things in line better through the Quark

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Luke,

If its any consolation my Esprit was not as contrasty on the surface detail today as the Equinox, The proms were still better in the Esprit.

Don't get me wrong the views were still excellent and maybe I am being a little picky, it might be that I need to be more selective when tuning.

Mind you I did swap diagonals betwixt the 2 last night and this could be the cause.... I will try it out ... its not an aperture thing as both of mine are 80mm

I think that's probably to be expected Shaun, at f4 you are operating at the extreme of the recommended limits ie f17 or so vs perhaps f28 at optimum.

I find the contrast very good in my Tak which is f5.9

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Stu,

I swapped the diagonals back so I wasn't using the stock diagonal that wasn't supplied with the Esprit for solar and all is back to normal :smiley: I also confirmed this by using a WO 1.25" diagonal and this too was excellent.

I will keep the Stock Esprit diagonal as a spare for the Equinox, there isn't enough inward focus to use it for dark skies in the Esprit ..... I am not too sure why they supply it with the scope if it isn't useable !!!!

Stu the Esprit is F5 thus its not so close to the limit (400/80) x 4.3 = 21.5, the Equinox works out at 26.8 in comparison.

Edited by Pig

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Stu the Esprit is F5 thus its not so close to the limit (400/80) x 4.3 = 21.5, the Equinox works out at 26.8 in comparison.

That's better [emoji2], not sure where I got f4 from, probably just remembered the 400mm focal or something weird!

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if you use the quark in front of the diagonal, will this increase the barlow factor of 4.2? Or is this independent is the distance between quark and ep.

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if you use the quark in front of the diagonal, will this increase the barlow factor of 4.2? Or is this independent is the distance between quark and ep.

I genuinely don't know the answer to that question! I will have an experiment and see what happens but I'm not sure I can get it to focus the other side. Will report back

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Just a little update re: the lower contrast with my Tele Vue 60. I tried straight through with the Quark and bingo, contrast was much improved, with a significantly better view. That's more like it! This one flies in my other scopes... :laugh:  It now feels like the same Quark I am used to, and it's working great at F6 (as it does at F9 too) :laugh:

Stu,

I swapped the diagonals back so I wasn't using the stock diagonal that wasn't supplied with the Esprit for solar and all is back to normal :smiley: I also confirmed this by using a WO 1.25" diagonal and this too was excellent.

I will keep the Stock Esprit diagonal as a spare for the Equinox, there isn't enough inward focus to use it for dark skies in the Esprit ..... I am not too sure why they supply it with the scope if it isn't useable !!!!

Stu the Esprit is F5 thus its not so close to the limit (400/80) x 4.3 = 21.5, the Equinox works out at 26.8 in comparison.

Edited by Luke
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One more question for quark owner. Does the 1.25" nose piece of the quark have a filter thread. I understand that my 80ed is right on the cusp of scope sizes recommended to use a uv ir blocker. But if I would get a filter, would it be enough to screw it in the nose piece or does it have to go before the diagonal to protect the diagonal as well as the quark?

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Best to put it before the diagonal Andre

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I have a Quark chromosphere on order and waiting for them to come in stock  (the wait is killing me!)

I'll be using it on my Equinox 80 along with a Baader UV/IR cut filter.  There are a couple of things I'm still not 100% clear on ....

Any anybody suggest a suitable FR to use with this to give full disc views.

Trying to get an idea on exactly which EP to use, I've tried running it through the various FoV calculators but they're not set to apply a FR & 4.2 Barlow combo!

Is there an adapter that will let me use 2" EP's on the Quark  (my 2" EP's are better quality than my 1.25")

Al

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Al.

A FR of 29 is the optimum, the Equinox will give you an FR of 26.8 due to the Quarks built in 4.3 Barlow. My advice would be not to change anything as the views are fantastic :smiley: Especially so if you block all the light out with a black cover of some form.

The TV 32mm just about fills the objective. However, the sun does move quite swiftly and its a bit of a struggle to keep it in the FOV, maybe a 40mm could just do it.... The problem with the low power plossl's is that the eye relief is huge and results in tricky eye placement. But even this is fine once mastered

Edited by Pig
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I'm actually moving away from the idea of using a Focal Reducer. I did a little side by side testing yesterday and it's clear that I get narrower bandwidth and better contrast at native focal lengths of the TV85 (f7) and AT106 (f6.5)

These give f30 and f28 respectively, pretty close to optimal.

What I do notice is that when the bandpass is narrower, I see some banding in the image which is slightly distracting when panning across the sun but is barely noticeable when static. The additional contrast is worth it in my eyes.

Field of view is a tricky one to calculate because it depends more on the etalon size of the Quark acting as a field stop than the eyepiece focal length or field stop.

By my calculations and experience, a 40mm Plossl in a scope with focal length longer than 450mm or so will not show any more of the sun than a 32mm. You get lower mag and see more of the etalon field stop ie it is like looking down a narrower 'tube'

Putting a focal reducer after the Quark does not gain you anything other than lower mag. The only way to gain more FOV is to put the reducer before the Quark as I have been doing. The x0.8 in the 600mm f/l TV85 gives 480mm and just about full disk views, but it is now operating at f5.6, or f24 ish, further from the optimal point. The contrast is lower because the light rays going through the Quark etalon at not as parallel as at f29.

So..... I think I'm coming round to the view that operating at as near to f29 as possible is best and gives the best contrast which is worth seeking out.

One thing which I experienced at SGLX when comparing the views between the Quark in various scopes and Shane's PST mod was that I found less need to shield my head to improve the view with Shane's scope. This may be because the bandwidth is wider and the prominences are brighter? Not sure. Overall though the views were comparable to my eyes so it is all swings and roundabouts as to how you get to the view!

Hope my ramblings make sense!!

Stu

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