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csb
16-10-2014, 05:23 PM
Hi

I used to have a Coronado PST which I sold in 2011. I mainly did visual observing. Now I am keen to take up solar viewing again.

I am thinking about a Lunt 50 with pressure tuning or a Lunt/Coronado 60mm Ha telescope or the Daystar Quark Ha eyepiece.

So, visually will I be able to see much surface detail with an of these setups? I seem to remember not seeing much with the PST although the proms were fantastic.

Will the 60mm show more detail than the 50mm?

Thanks Craig

Merlin66
16-10-2014, 05:59 PM
Craig,
I'm not sure the Lunt 50 is available yet.
Early discussions say it gives good "bang per buck" and is recommended over the Lunt 60.
I had and used an original SM60 scope - the etalon was great but the scope was very average. I moved the front etalon onto a ED80 - Majic!!!
The "new" SM60II version is a beefed up PST with a similar internal etalon - I don't like it.
Hope this helps.

csb
16-10-2014, 06:30 PM
A few days ago, I phoned Ron Gibson of Sirius Optics, about the Lunt 50 and he informed me that there is a delay due to the filters, manufactured by a 3rd party, being below Lunt's standard. So you are correct there is a delay from a couple of months ago.

casstony
16-10-2014, 06:47 PM
For visual use a double stack is more important than aperture; I'd recommend a double stack smaller scope over the same priced larger aperture single etalon.

csb
16-10-2014, 09:54 PM
I'm not keen on spending the extra cost of double stacking.

Can filaments and granulation be seen EASILY through a 50 or 60? Other features?

casstony
16-10-2014, 10:00 PM
You need the double stack to make detail on the disk easily visible. A filament that looks black with the double stack may also be seen as light grey in a single etalon, but the double stack gives a huge boost in contrast.

csb
17-10-2014, 06:43 AM
A very compelling reason to consider double stacking. Thankfully it can be done later.

Will the 60mm show much more than the 50mm?

Will the 60 have a bigger full disc image through the eyepiece than the 50?

There is a Lunt 60mm with a 12mm blocking filter in the classified - will that allow fir an image double the size of a scope with a 6mm blocking filter?

brian nordstrom
17-10-2014, 07:37 AM
:) Hi , the size of the disc is generated by the focal length of the scope ( eg magnification ) when using any given eyepiece just like any telescope .
I had ( and loved ) a Coranado 'Solarmax 40mm and it would show both surface detail and prominances very well just by tuning the elation , PST's cant do that but I am sure Lunts have a similar system , that's all you need here .
On the blocking filter size , that is only a mask in the diagonal that limits the FOV , not magnification .
Hope this helps .
One more thing ,, aint Ha solar observing addictive ?? ;), I should never have sold mine .
Brian.

casstony
17-10-2014, 09:04 AM
Not much difference between 50 and 60mm.

The different size blocking filters simply allow a larger field of view; at a given magnification the 12mm will show twice the fov of a 6mm blocking filter.

Merlin66
17-10-2014, 09:26 AM
The PST can tune across the Ha wavelength - from the red wing to the blue wing.
The size of the blocking filter (BF) is determined by the clear aperture needed to show the solar disk.
Based on 1/100 ( the size of the solar disk is approx. 1/100 the focal length) for a 400mm fl (PST/ Lunt60) the BF needs to be 4-5mm, for a 1000mm fl (TS102 etc.) a BF10 (10mm) would be good and for even longer focal lengths the BF15.

(Solar Ha scopes are only designed for limited field of view - due to the etalon design and accommodate the 1/2 degree solar image with a bit to spare - there's no wide angle option)

SteveInNZ
17-10-2014, 09:27 AM
Does the size of the blocking filter have any influence on the size of the tuning "sweet spot" ?
How does the Quark compare in terms of surface contrast to say a 50mm single or double stack ?
I agree about the solar Ha addiction - It's worse than aperture fever.

Steve.

Merlin66
17-10-2014, 09:31 AM
Steve,
The blocking filter has no impact on the "sweet spot" - that comes from the etalon design and tuning arrangement.
The Chromo Quark gives much more resolution and, working at around f25+ a very narrow field of view. The contrast, compared with a conventional double stack, IMHO looks "soft". Maybe similar to a single stack with hi magnification.
(I think to get the max from the Quark you need to image and do a lot of post processing)

Poita
17-10-2014, 10:16 AM
If you want to pay the post and insurance, I will send you my Lunt 60 to have a play with for a month. That should give you a good idea of what you can see :)

I will be unable to use it for the next 6 weeks, so happy to loan it to you. You really need to experience it firsthand to know.

I see filaments and surface detail effortlessly with it, miles ahead of the old PST I had, but everyone seems to have a different experience with solar viewing, so trying it out seems to be the only way to know.

Bounce me a PM, or better still, and email and I will send it off.

gbeal
17-10-2014, 10:58 AM
Blimin' heck, nice gesture Peter.
Gary

Monstar
17-10-2014, 02:51 PM
Very generous indeed, and not the first time I've seen acts of generosity on this forum, what a great community.

Myself, I could not take someone up on such an offer in case I damaged it or it got damaged in transit. I'd feel terrible.

Poita
17-10-2014, 03:02 PM
That's what insurance is for :)

I've loaned out everything from CCD cameras, to C8, G11, Hyperstar, Adaptive Optics unit, various filters, even a C14, and it as often come back in better condition than I sent it in!

With some gear, the only way to know is to try it out, and not everyone has access to a club or local owners.
I'd rather someone use my gear than it sit in the cupboard.

csb
17-10-2014, 04:27 PM
Thanks Peter, that IS very generous of you. I would certainly love to have use of that scope for a while. But I will have to think about it too and check the cost.

I will pm you within a few days (the weekend is here).

csb
19-10-2014, 08:22 AM
Well thanks for the offer Peter but I have decided not to take it up. Mainly because I think I would like to view through both a 50 & 60 mm to help decide. Cost is an issue and looking through just a 60mm I couldn't really know if I'd be just as happy with views through a 50mm.

Your comments quoted below, however, were very helpful. This was the kind of opinion I was after. I think that viewing through a 50mm should be nearly as good. I was certainly happy with what I saw in the PST.


And you are certainly correct:


And I am still considering the Lunt 60 up for sale in the Classifieds. And the Quark Ha eyepiece.

Poita
20-10-2014, 09:10 AM
I was thinking you would want to check if you were happy with the views through a 60mm, if you weren't then a 50mm certainly wouldn't do!

I see filaments and proms easily, other people say they just see a red disc, so it is really something you want to try before buying.

csb
20-10-2014, 11:43 AM
Ok, on further thought, I will take up your offer.

I am seriously considering the Lunt 60 thats up for sale (although the seller has not responded to posts or pm). So having a view through your scope should help with that decision.

Now it depends on what the shipping n insurance cost will be. I will send a pm later today.