Just ordered a Lunt LS50THa scope

[Highburymark]

On 1 April 2017 at 10:05, Peter Drew said:

I would hope by now that any "Newbie" to Ha solar viewing will understand that best results involve a learning curve with respect to using Ha telescopes and the external conditions that have an affect on their performance. My large Ha telescope can give outstanding images but on many occasions complete rubbish. The slightest amount of haze in the air quickly reduces the contrast and provides a red fog round the image. I use high magnification as I like to see the detail in the detail, seeing just a portion of the solar disc completely eliminates any sweetspot issues. Solar telescopes are sophisticated instruments but learning how to use them pays dividends. Tuning of etalons is based on the refractive index of the air that is in the gap between the etalon plates. Tilting the etalon increases the width of the air gap and hence its refractive index, pressure tuning increases the air gap pressure, this also changes the refractive index of the air. Take your pick.  

Absolutely - getting the best view with the LS50DS involves careful control of focuser, pressure tuner, magnification if using a zoom, nudging the scope if on undriven mount, and tilting the double stack filter, all the while adjusting the view to position the sweet spot. Then there's the art of placing black cloth on head and not passing out in midday sun.

[johninderby]

Sucess at last. 

New Pentax XF Zoom arrived this morning and the sun was out, at least for a while anyway, so time to give the scope another go and test out the new zoom. The Pentax XF Zoom had been my favourite Ha eyepiece before. Compact and lightweight for a zoom.

At last there was activity to observe with some nice sunspots and an active region near the limb. Saw a lovely tall straight pillar flare that was very bright and razor sharp. Really stood out. Of course at this point along came the clouds but at least I had enough observing time to find out if the scope was a good one and it certainly seems to be. What a difference compared to the one that was returned.

Also very pleased with the new eyepiece. It was just as good as I remembered. 

               John

 

[sloz1664]

John, I felt for you all through your trials and tribulations. Some folk don't realise that a good retailer is a "must" when buying equipment. It helps a great deal, as in your case. Great to see a happy ending.

Steve

[Highburymark]

10 hours ago, johninderby said:

Sucess at last. 

New Pentax XF Zoom arrived this morning and the sun was out, at least for a while anyway, so time to give the scope another go and test out the new zoom. The Pentax XF Zoom had been my favourite Ha eyepiece before. Compact and lightweight for a zoom.

At last there was activity to observe with some nice sunspots and an active region near the limb. Saw a lovely tall straight pillar flare that was very bright and razor sharp. Really stood out. Of course at this point along came the clouds but at least I had enough observing time to find out if the scope was a good one and it certainly seems to be. What a difference compared to the one that was returned.

Also very pleased with the new eyepiece. It was just as good as I remembered. 

               John

 

So glad things are working out for you - and that you have the XF - it's a magnificent solar eyepiece

[johninderby]

Have been thinking about selling the LS50 and getting an LS60 without PT. Yes this one does work fine but want a bit more. 

Will mull it over for a few days. 

           John

[Davey-T]

28 minutes ago, johninderby said:

Have been thinking about selling the LS50 and getting an LS60 without PT. Yes this one does work fine but want a bit more. 

Will mull it over for a few days. 

           John

I have the LS60DS with B1200 bf and it is a step up from the LS50 as you would expect for the price, the focuser is better than the LS50 plus there are plenty of focuser upgrades available, I've fitted a Moonlight on mine.

Dave

[Live_Steam_Mad]

29 minutes ago, johninderby said:

Have been thinking about selling the LS50 and getting an LS60 without PT. Yes this one does work fine but want a bit more. 

Will mull it over for a few days. 

           John

I am interested in your LS50. PM sent.

Regards,

Alistair G.

[Stu]

Gents, could I kindly ask you to keep buying/selling to the classifieds.

Many thanks  

[Live_Steam_Mad]

Hi, I too just bought myself a brand new Lunt LS50THa Pressure tuned with B600 Blocking Filter. It arrives tomorrow. If it shows detail approaching what I see on the GONG Network then I suppose I'll be happy LOL ;-

http://halpha.nso.edu/

...I'll find out soon enough tomorrow if there's a clear view of the Sun. I ordered the OTA and dovetail, nothing else. It's to go on my Celestron CG5 ASGT mount. I have some eyepieces that I can use. I'll let you know how I find the views from St.Helens, NW England.

Regards,

Alistair G.

[Live_Steam_Mad]

On 14/03/2017 at 20:43, johninderby said:

 

Funnily enough the stock focuser just unscrewed by hand on mine.

I'm not worried about getting a peoperly working one in the end as even if this one doesn't play ball FLO will replace it with no problems. Fingers crossed the O-ring sorts it. Although just took a look at the forecast and the sun is sems to be going into hiding over the next few days. 

         John

Yep I too just checked my Lunt 50 and the stock focuser unscrewed with the force expected (not too tight really) so I'm pleased on that score.

It arrived this morning but I haven't had first light yet. Today's not looking promising. I'll have to try again tomorrow.

Regards,

AG

[Tyson M]

The lunt 50 is exudes build quality and feels like a well made Telescope.

 

The helical focuser is a bit wonky but you get used to it.  There are after market upgrades if you don't get on with it. 

 

You have to completely unscrew the pressure tuner and rethread it at first to build pressure, make sure there is lots of grease.

 

 It should last several days / weeks before needing to rethread it again.

Of course, gratuitous tuning can be applied , in combination with focusing , can look at various parts of the disk better. Like proms or the surface.

I usually just tune for uniformity and leave it. Also , different parts of the blocking filter work better than others, known as the sweet spot. Move the sun all over the view in the blocking filter to figure it out. It should be center or close to anyways.  

 

Takes some playing around with it at first but it becomes second nature and fun to use. 

 

Congrats on the 50. Warning, if you enjoy it so much (like I did after a summer) you're starting down the expensive path of solar haha. 

[Tyson M]

Consider the focal length when using eyepieces. Yes good quality eyepieces show a sharper view but you don't need expensive glass to enjoy it. 

Let your eye adapt to the red light. The more you look the more you see. You should see close what you see on GONG, corrugated rough, plasma surface and faint proms on the periphery, once tuned properly.

 

You can highlight proms with less pressure (less turns) and focus more on the disk surface with more turns , to an extent. At least in my experience with the 50 and 60.

I usually get it to a happy medium where I see everything well. 

[Live_Steam_Mad]

23 minutes ago, Tyson M said:

The lunt 50 is exudes build quality and feels like a well made Telescope.

 

The helical focuser is a bit wonky but you get used to it.  There are after market upgrades if you don't get on with it. 

 

You have to completely unscrew the pressure tuner and rethread it at first to build pressure, make sure there is lots of grease.

 

 It should last several days / weeks before needing to rethread it again.

Of course, gratuitous tuning can be applied , in combination with focusing , can look at various parts of the disk better. Like proms or the surface.

I usually just tune for uniformity and leave it. Also , different parts of the blocking filter work better than others, known as the sweet spot. Move the sun all over the view in the blocking filter to figure it out. It should be center or close to anyways.  

 

Takes some playing around with it at first but it becomes second nature and fun to use. 

 

Congrats on the 50. Warning, if you enjoy it so much (like I did after a summer) you're starting down the expensive path of solar haha. 

I took a look at my pressure tuner. I unscrewed the black barrel all the way out and had a look at the brass barrel. The threads looked very good on the brass barrel. The O ring looked pretty round in section and not compressed at all. It did look very dry in there, hardly any grease at all. The black barrel goes on with little force but then when the O ring gets up to the brass section inside the friction increase is considerable. I don't much notice it being progressively harder to turn as I screw it further in, apart from near the end of travel when it's all the way in and it's then very hard to turn for the last few mm. It looks to be new old stock, it has a serial number beginning "2015..." which I assume means it has sat in a storeroom / warehouse for 2 years before I got it.

I am liking the stock focuser so far, feels smooth but firm (a little bit tight i.e. resistance to turning is a little higher than I was expecting). When I try to push the diagonal left and right there is a very small clunking sound, a little itsy bit of play, feels good quality to me. The travel is 20mm according to the scale on it.

I got the B600 Blocking Filter. I checked the Etalon and I think I can see the 4 Fused Silica pieces that separate the plates of the Etalon. There is some slight dust particles and tiny 1mm length dust hairs in the Etalon, on the top and underneath the glass surfaces. There was slight dust particles on the front lens, and some small coating flaws on the anti-reflective front lens. Frankly I could have got them cleaner myself LOL.

I notice that the ITF filter in the bottom of the diagonal is TRANSPARENT to visible light!! I hope it's a UV block or something. I know Lunt uses a proper ERF filter in the OTA to remove the heat (IR). ITF filter looked nice and clear, no clouding. BF filter looked OK.

Still can't get first light yet, looks to be after 3PM tomorrow that I'll get a chance to test it.

Best Regards,

Alistair G.

[Tyson M]

I would get some grease in there then.  Call Lunt or your supplier. Lunt USA typically sends them for free

 Yes, internationally ( I live in Canada) .

 

Or they can point you to an alternative brand of grease. High pressure and temperature kind , if for some odd reason you can't get any from them.  

[Live_Steam_Mad]

Two more things I noted about my new LS50... firstly the Lunt 100mm GP dovetail plate that I bought with it for my Celestron CG5 ASGT mount was supplied with 2 bolts where I tried an Allen Key on the bolt heads to tighten them, but 4mm was too loose and 5mm was too big. Turns out they are Imperial sized heads and I had to use a 3/16 Allen key to tighten them, but the fit was perfect to the clam shell that came with the LS50 and the assembly is now ready to mount to my CG5 tomorrow.

Secondly I just made sure that the small Allen head bolt which is under the pressure tuning cap (small black cap that unscrews) was tight. That doesn't seem to be Imperial, I tried 3/32 but it was too loose it seemed and 7/64 was too tight, but a 2mm Allen key seemed about right. I bought the Allen keys for about 3 quid off Ebay as a combined Imperial / Metric set.

Regards,

AG

[Live_Steam_Mad]

I was just reading about some people having Lunt ITF filters go cloudy so I looked and mine is perfectly clear (it is the one at the scope end of the diagonal), I have since learned that it is an IR filter ;-

https://www.cloudynights.com/topic/445617-itf-h-alpha-filters/

...and it should be clear and with a slight green tint.

However I also noticed 2 significant and fairly long scratches on my diagonal (Blocking Filter diagonal) mirror, rather annoying.

Regards,

AG

[Live_Steam_Mad]

Ahh, what I thought was an ITF filter is instead a simple BG glass filter ;-

https://www.cloudynights.com/topic/433046-polishing-optical-acrylic-lens-element-in-a-lunt-s/#entry5592771

" We do not use ITF's in our systems anymore. The poster image you have is very old. This is BG glass. There are no coatings on it. The glass itself is the filter. We have not had any film on any other element.
Thanks,
Rikki Hocking
Lunt Solar Systems"

AG

[Live_Steam_Mad]

Holy Cow!! I just came in for a break from First Light viewing with the LS50, the view is spectacular!!!

Large Prominance on the top of Sol at 12:30, smaller ones at bottom, I can see the "double" layer around the perimeter / spicules, there is quite a strongly contrasted dark fissure close to the left of AR2670, and a strongly contrasted orange peel texture all over the Solar disc! The view was crisp. I was in heaven!

By far the best view was with a TeleVue Radian 8mm eyepiece and Dioptrx 3.5. THANK YOU LUNT and TELEVUE !!! This is awesome!

A couple of slight negatives ;- I seemed to be loosing pressure by about 1/8 of a turn on the pressure tuner every 2 mins.

I could not come to focus with my 2x Revelation / GSO Achromatic Barlow used with my TeleVue 32mm and Meade 26mm Series 4000 Plossl, I was needing just a few more mm of in-travel. So I took off the Barlow lens group and used it on the bottom of the eyepiece and used a UV/IR filter as a spacer to get more magnification but the Barlow factor was about 1.3 ish it seemed.

The Sweet Spot was quite annoying at low magnifications but was hardly noticeable at high magnifications. At least the sweet spot was in the centre!

Well looks like I have lucked out and got a good one! Thank goodness. There was so much to see and so much prom detail that I almost ignored AR2670!

Seeing Proms for the 1st time was like a revelation, a magical experience. Very recommended.

Best Regards,

Alistair G.

[Live_Steam_Mad]

Oh yeah and I found the view visually with my eyes of the surface detail with the 8mm Radian is more contrasty through my LS50 than it is today through any of the GONG H Alpha network cameras!!

Cheers,

AG

[Tyson M]

On 8/12/2017 at 09:17, Live_Steam_Mad said:

Holy Cow!! I just came in for a break from First Light viewing with the LS50, the view is spectacular!!!

Large Prominance on the top of Sol at 12:30, smaller ones at bottom, I can see the "double" layer around the perimeter / spicules, there is quite a strongly contrasted dark fissure close to the left of AR2670, and a strongly contrasted orange peel texture all over the Solar disc! The view was crisp. I was in heaven!

By far the best view was with a TeleVue Radian 8mm eyepiece and Dioptrx 3.5. THANK YOU LUNT and TELEVUE !!! This is awesome!

A couple of slight negatives ;- I seemed to be loosing pressure by about 1/8 of a turn on the pressure tuner every 2 mins.

I could not come to focus with my 2x Revelation / GSO Achromatic Barlow used with my TeleVue 32mm and Meade 26mm Series 4000 Plossl, I was needing just a few more mm of in-travel. So I took off the Barlow lens group and used it on the bottom of the eyepiece and used a UV/IR filter as a spacer to get more magnification but the Barlow factor was about 1.3 ish it seemed.

The Sweet Spot was quite annoying at low magnifications but was hardly noticeable at high magnifications. At least the sweet spot was in the centre!

Well looks like I have lucked out and got a good one! Thank goodness. There was so much to see and so much prom detail that I almost ignored AR2670!

Seeing Proms for the 1st time was like a revelation, a magical experience. Very recommended.

Best Regards,

Alistair G.

You probably need some grease about the PT slowly losing pressure. 

Glad you are enjoying your view so much. It really is a magical experience. 

If you buy brand new, I'd say you're almost guaranteed a good one. If not, you are protected and they will send you a replacement right away. 

My Lunt 60 B1200 is my most used scope. I too enjoyed using it again this weekend. 

 

[Live_Steam_Mad]

Wow yesterday was a total joy. I got almost an overdose of Solar observing. I was using mostly the 8mm Radian, plus a UV/IR filter (as a spacer) and a Revelation / GSO 2x Achromatic Barlow and was maybe at 60x magnification for long periods of time, and I was seeing detailed strongly contrasted Proms, a ton of surface detail, even a BRIGHT flare around AR2671 the new large Sunspot near the edge of the disc. The illumination and detail and contrast was fairly constant across the field with hardly any sweet spot effect. This scope loves relatively high magnifications! It's gonna be total knockout if I ever get the double stack.

I also distributed some grease in the brass chamber inside walls (still VERY dry in there) and the pressure was now holding for LONG periods of time, so much so that I was able to broadcast on NSN.com for a half hour or so and not see any change in the tuning even though I didn't touch the tuner after I started casting.

Regards,

AG

[Live_Steam_Mad]

On the negative side, the request that I sent to Lunt USA for some new O rings / grease almost 48 hours ago has gone unanswered so far. I'll report back if I get a reply, I'll try them twice before giving up and trying Lunt's German service department or the place where I bought the scope.

AG

[Tyson M]

17 hours ago, Live_Steam_Mad said:

On the negative side, the request that I sent to Lunt USA for some new O rings / grease almost 48 hours ago has gone unanswered so far. I'll report back if I get a reply, I'll try them twice before giving up and trying Lunt's German service department or the place where I bought the scope.

AG

Solar eclipse preparation, they are touring the USA along the path of totality promoting the business and giving out solar glasses if I am not mistaken.