Just ordered a Lunt LS50THa scope

[jabeoo1]

There is vaguely anything to focus on at the moment, I got nothing out of mine the other day with the seeing being so bad coupled with the image below, I think I managed to just about see a tiny prom but only just !

 

 

 

[johninderby]

According to Steve at FLO the O ring in the picture looks a bit "flat" and looks like doesn't protrude enough to seal properly so we'll see if a new O ring helps. If not it goes back. 

I've been using HA scopes for about eight or nine years now so I know what to look for and believe me this Lunt just isn't right at the moment. 

          John

[jabeoo1]

Just now, johninderby said:

According to Steve at FLO the O ring in the picture looks a bit "flat" and looks like doesn't protrude enough to seal properly so we'll see if a new O ring helps. If not it goes back. 

I've been using HA scopes for nearly 10 years now so I know what to look for and believe me this Lunt just isn't right at the moment. 

          John

I hope it gets sorted John, look forward to your proper 1st light report. 

[johninderby]

I hope it's as simple as replacing the O ring. The O ring does seem to be the weak point of the design as it has to be perfect or else.

            John

[Highburymark]

4 hours ago, johninderby said:

Took the pressure tuner apart and found the reason for the tuner not having much effect.  New O ring on it's way from FLO.

                    John

John - the o-ring looks normal to me. I  was in a similar position to you in the summer/autumn of 2015 (you can find various threads with pictures elsewhere on this forum) in that I wasn't happy with the pressure on my LS50 so I added another o-ring to the second groove. This makes it very difficult to reattach the pressure tuner - but I managed it, and the scope has performed well ever since. Only my personal experience but worth you knowing about. I also think the lack of features on the disc is relevant - I've never seen such an inactive sun.

[johninderby]

I'll try using two O rings if replacing the original one doesn't help.  Also have a tube of silicone O ring graese handy to make sure it's properly greased. Yes lack of features doesn't help in testing but I've never seen such total lack of detail before even under the worst viewing conditions.

                John

[Highburymark]

You have more experience with ha than I do - but the LS50 is a quirky little scope. Even with the second o-ring fitted, I have to screw the tuner inwards until no more grooves are visible. And don't get me started on the focuser - I recently bought a Moonlite (from fellow SGLer Jabeoo) but couldn't remove the stock focuser. Hence why the scope is currently with the distributor in Germany being sorted out. But persevere with these challenges and it will repay you - as long as the Sun gets its act together and starts putting on a show

[johninderby]

11 minutes ago, Highburymark said:

You have more experience with ha than I do - but the LS50 is a quirky little scope. Even with the second o-ring fitted, I have to screw the tuner inwards until no more grooves are visible. And don't get me started on the focuser - I recently bought a Moonlite (from fellow SGLer Jabeoo) but couldn't remove the stock focuser. Hence why the scope is currently with the distributor in Germany being sorted out. But persevere with these challenges and it will repay you - as long as the Sun gets its act together and starts putting on a show

 

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

[garryblueboy]

Hope you get it sorted I love mine best solar views I have had 

[johninderby]

Well no luck with the new O ring. Even tried two O rings but no better. Adjusting the tuner has no effect. Looks like the etalon has been knocked loose / out of postion during shipping.and will need re-seating. Anyway being collected on Monday.

            John

[Moonshane]

Sorry to hear of your problems John

Hope it gets sorted soon.

[johninderby]

At least with Steve at FLO on the case I know it will get sorted.  

                  John

[Highburymark]

Commiserations but good to know you're in safe hands with FLO.

 

[Tyson M]

I am not thrilled with the focuser on my new one either but it works. 

The seal is a bit of quirky design IMO, hard to tell by a picture alone. 

You can save a lot of money and a bit of weight by going tilt, but ultimately I went back to the PT model.

I am going through the same issue here in Canada with my new 60PT, but I am no stranger to this, as it happened with my prior 50 as well.

First step- regrease  (done) go out and observe and try and tune it.

If that doesn't work, replace one o ring, go back out test.

Doesn't work? Replace second o ring  (or add one if you can), try again.

If all of that doesn't work, then its time to go back to Lunt, usually at the expenses of shipping one way plus packaging if you didnt keep the original box.

 

I hope you (and myself) get it sorted soon, good thing they offer 5 year warranty with new purchases that are registered.

 

Customer service is top notch with them as well. 

 

My 50, once those issues were ironed out, was a fantastic visual scope. 

 

 

[Tyson M]

On 3/4/2017 at 05:11, johninderby said:

Just ordered a Lunt LS50THa scope from FLO 

I had been undecided about going for the 50 or the 60 but in the end decided the 50 was the better buy. I mean yes I would have liked the 60 with PT and Feather Touch but my wallet said otherwise. Have also ordered the Feather Touch focuser, Sol-Searcher and a short dovetail bar. Still works out hundreds less than the cheapest 60 but has the pressure tuning and Feather Touch that I wanted and can be double stacked in the future if I want to.

Got my old Manfrotto 475 tripod with modified 405 geared head down from the loft and dusted off. A bit overkill for such a small scope perhaps but you can't have too stable a mount. Have used a C8 on this mount so it won't even notice the Lunt. Will still be light enough to carry the full set-up outside one handed though.

I appologise in advance for the cloudy and rainy weather to come in the next couple of weeks.

         John

 

 

PS I love that Manfrotto tripod. Looks like a perfect GnG mount. 

[johninderby]

19 minutes ago, Tyson M said:

PS I love that Manfrotto tripod. Looks like a perfect GnG mount. 

Yes it's a great GnG tripod although the 405 geared head has nearly doubled in price since I bought mine.  Usefull for other things than solar though.

         John

 

[Tyson M]

My Porta II mount head package on my EQ6 legs is not quite as grab and go as I would like, but I am more or less content with it.

 

 Your tripod and mount head look like the exact thing I was looking for.  

 

Just more money than what I had at the time.  New, this appears to be almost $1000 Cad. 

 

 

 

 

[johninderby]

The tripod and head cost me about £400.00 at the time but crazy how much the price has gone up. Just too expensive now.  

           John

[johninderby]

Replacement scope on it's way.  

The engineer who examined my original scope said it " lacked the punch it should have"  which is an understatement. I knew it wasn't right and pleased that the engineer agrred.

Fingers crossed scope no.2 is OK.

                John

[johninderby]

Replacement scope artived. Took a quick look through it and all I can say is maybe. Still nothing to be seen but faint hints of surface deatail,seen around the edges.  Think seeing is pretty rubbish this morning so will try again this aft.

               John

[Tyson M]

How is it? Any follow ups?

 

I had mine out today briefly- after the regreasing and a bit warmer temperatures and it tuned the entire disk  just fine!

 

 Checking GONG, proms were all there!   A bit faint, still have to work on tuning those. Could have been the seeing conditions.

 

 

But active region 2645 was very sharp! Loved watching the 2 main spot regions, there was bright, lighter red activity going on on each, almost looked like potential flaring imminent.

 

Saw the best filament of my life today with first light of the LS60THa. It looked like it was connecting two spots on the middle AR2645 region. 

My right eye has trouble looking into the scope by itself, perhaps a different focus point than my left. I feel like need for some cheaper binoviewers in the future.

 

Hope you get some more sun with yours.

 

 First focus the disk looking for surface features: then tune PT slowly and refocus if necessary.  The more/ longer you look, the more you see. 

 

 

[Tyson M]

If it looks like just a white light view, with no Ha surface features or proms, you know there is an issue. You will know when you see it, as it should be like nothing you have ever seen before if its your first Ha scope. Almost like a corrugated look to the disk.

 

Most problems I hear arent concerning that, its that their Ha scope (not just lunt) has a sweet spot where detail is only visible good in a particular spot on the blocking filter viewing. Or only part of the disk tunes, not all of it.

 

My LS50THa was like that, it was very hard to get the full disk tuned only partial. Either it was finicky with the PT or there was a sweet spot with the blocking filter, I wasnt completely sure. I had a B400, so maybe that was the issue. 

 

This time, I opted for the largest blocking filter I could afford, as I was hand tracking at times and imaging, and if there was a sweet spot it would be easy to isolate and keep there. Anyways, I think the newer lunts should be better quality regarding that, and mine doesnt appear to have a sweet spot, rather than my preowned lunt 50 I noticed was made in 2014  

[spaceboy]

6 hours ago, Tyson M said:

If it looks like just a white light view, with no Ha surface features or proms, you know there is an issue. You will know when you see it, as it should be like nothing you have ever seen before if its your first Ha scope. Almost like a corrugated look to the disk.

 

Most problems I hear arent concerning that, its that their Ha scope (not just lunt) has a sweet spot where detail is only visible good in a particular spot on the blocking filter viewing. Or only part of the disk tunes, not all of it.

 

My LS50THa was like that, it was very hard to get the full disk tuned only partial. Either it was finicky with the PT or there was a sweet spot with the blocking filter, I wasnt completely sure. I had a B400, so maybe that was the issue. 

 

This time, I opted for the largest blocking filter I could afford, as I was hand tracking at times and imaging, and if there was a sweet spot it would be easy to isolate and keep there. Anyways, I think the newer lunts should be better quality regarding that, and mine doesnt appear to have a sweet spot, rather than my preowned lunt 50 I noticed was made in 2014  

You can tune a Ha scope off band so it gives you WL (only sunspot) and Ha (chromosphere / prom) views so not necessarily and issue, just more a case of requiring tuning.

Compared to a PST my LS60Tha has no discernible "sweet spot" as such. More like a banding if anything?? and is far more evenly detailed / illuminated. Minor adjustments are required as I scan the surface and limb but when you consider the sun is truly humongous and a 3D sphere I'd be very surprised if I didn't have to compensate for perspective.

As far as my limited knowledge extends the sweet spot is the result of the etalon and not of the BF. Having a larger BF for visual is not as advantageous as it is when imagine where camera sensors are a fixed size (base magnification) and images show vignette when use with smaller BF.

 

 

As for your LS50tha John it might be worth dropping a PM over to @DRT as he has a LS50tha and I don't think he is too far from you. He is a really nice chap and I'm sure would be more than happy to do a side by side comparison (weather permitting). I know when I got my LS60Tha that I was underwhelmed at first. Yeh there was detail but knew there should have been more over what I had previously seen in a 40mm PST's. It was returned and "apparently" the etalon was swapped out but I am now informed there is a higher chance it was more likely an ITF that was replaced. Either way it came back better than it was sent. As you have now received a replacement?? or repair I'm not sure what to say as its highly unlikely that two scopes have similar issues?

I know when I was looking to get a Ha scope LS50Tha I came across a youtube vid (think it was) explaining their problems with the pressure tune system. It was also speculated that the tilt tune would in theory at least, more than likely cost more to produce than the PT version?? (although as they are currently already in production and more tooled towards TT they cost less that PT at present) There is also the possibility PT Maybe just a case of selling the next best gimmick at a premium ?? When the PT were first voiced there was chatter that they would eliminate the "sweet spot" but this is not the case and some forums argue there is not a huge difference in tuning capability between the tilt and PT models ?? The main difference being there have been more problems reported of failed seals and in some cases crossed threads from priming the PT than tilt tune issues. Although I'm sure when the TT were first released they too would have had their share of teething problems as is the case with most things new.

You probably already know this but, I do know Ha requires a relaxed eye, good seeing, transparency and some eye cupping / blanket over your head to get the very best from the views. Clear blue skies are not necessarily a good indication of good detail. The current seeing conditions can be the culprit of flat views and you may be inadvertently tuning out detail when all you need do is wait. Lunts don't seem to have the same immediate throw of tuning as you see in PST's and to my eye at least are much more subtle. As with focusing you can tune either side of great so be patient.

I hope you are able to get it sorted soon John and good to see you posting again mate.

[Peter Drew]

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.  

[johninderby]

Yes good to be back. 

New scope and poor seeing can be a bit frustrating particularily when you are still trying to get the "feel" of the new scope. The old tilt tuner did make it easier to tune although think the pressure tuning will give slightly better results once I'm more familiar with using it.

One problem with the new house is the big trees at the bottom of the garden that block the sun untill later on in the morning at this time of year, at least from the garden. May have to resort to observing out of the bedroom window.  

            John