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Hope it gets better - Lunt LS50THa


DIGITALid

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A quick background.

I had previously spent my fair share of time in observatories and looking through a few telescopes.  As an adult I FINALLY got a 6" Dob that I can view some distant objects with.  It was exciting that first time I accidentally came across the Orion Nebula.  That moment was awesome.  Nothing compared to the goosebumps I got in the hot sun when a coworker allowed me to look through the eyepiece of his Coronado PST for the first time.  I had NEVER seen anything like that.  The detail in the sun was very impressive.

I watched the price on that telescope inexplicably increase and never come back down.  I did my research.  I waited years!  Finally I decided to plunk down the cash for the Lunt LS50THa.  I got the B600 filter because I wanted to be able to take pictures at some point.

I spent about an hour today with a clear sky tracking the sun. (I'm working on saving for a better tripod and mount.)  So far... I am not feeling the $1,000 worth of a view I was hoping for.  I could BARELY make out ANY detail the surface.  When I could, it was only visible in one or two areas.  There was a dark areas on what to me as I faced the sun setting on the West top right and bottom left.  But it did not appear at all like what I saw through the much cheaper PST.  I HOPE its something I am doing wrong.  I tried a variety of different eyepieces.

I hope it gets better. :(

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Have you tried tuning the echelon ? you'll need absolutely clear sky to get the most out of proms. I got this yesterday with a Lunt 35, in addition there were several  very obvious filaments with surface granulation across the surface. its a struggle starting out and you must be patient enough to get your eye and get adapted to what you are seeing. Moving the view around will hit a sweet spot , don't expect this to be right across the view. let us know how you are getting on, Nick.fullsizeoutput_115.thumb.jpeg.d8d8fbf560e724003eadfe7d26bb1ccc.jpeg

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- Following this thread with interest: I hope to get one of these at some point.  I've read many threads about the pressure tuner needing to go almost the whole way in, and also about o-rings and re-greasing... some people getting a kit sent out from Lunt.

I hope you get help here, and start seeing stunning views soon!  The impression I have reading up is that Lunt give very good support. Best of luck :)

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As a solar observer, I feel your pain, DIGITALid.

However, two things I would highlight:

1) The Sun is very quiet just now - and, unfortunately, unlikely to 'pep up' for some time as we are heading into Solar Minimum. When I first started 'on the bright side' the Sun was very busy, with lots of spots, filaments and breath-taking proms. That is not the case these days. ?? However, Ha always has something to offer and we have just witnessed a very large sunspot cross the surface - which may re-appear if it hasn't decayed too much going round the far side.

2) Don't worry too much about different EPs - concentrate your efforts more on tuning and focusing - the latter is critical and it can be very, very tricky to hit exactly the right spot (no pun). I had a lot of soul searching when I acquired my Lunt, which didn't seem to be performing as well as my SM40. But I got an unusually long session last week and after a lot of faffing around it finally sang to me! ???

Dont despair, you'll get there, too. Just be aware that the Big Fella's having a wee snooze at present. ??

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10 hours ago, cotterless45 said:

Have you tried tuning the echelon ? you'll need absolutely clear sky to get the most out of proms. I got this yesterday with a Lunt 35, in addition there were several  very obvious filaments with surface granulation across the surface. its a struggle starting out and you must be patient enough to get your eye and get adapted to what you are seeing. Moving the view around will hit a sweet spot , don't expect this to be right across the view. let us know how you are getting on, Nick.

Thank you for your response.  The echelon?  I don't believe I did.  All I did was pressure tune and adjust the (I guess helical) focus ring.  I don't get nearly as close a view as you have.  When I use my 17mm eyepiece I see the big orange ball.  In focus, but no surface detail at all.

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9 hours ago, niallk said:

- Following this thread with interest: I hope to get one of these at some point.  I've read many threads about the pressure tuner needing to go almost the whole way in, and also about o-rings and re-greasing... some people getting a kit sent out from Lunt.

I hope you get help here, and start seeing stunning views soon!  The impression I have reading up is that Lunt give very good support. Best of luck :)

Thank you me too.  I've been reading some other forums.  Some folks say there are known recurring issues with an O-ring in the pressure tuner.  I will do more research on this as it sounds like those users are having the same problems I am.

Forum topic on CloudyNights <--Is this allowed???

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8 hours ago, Floater said:

As a solar observer, I feel your pain, DIGITALid.

However, two things I would highlight:

1) The Sun is very quiet just now - and, unfortunately, unlikely to 'pep up' for some time as we are heading into Solar Minimum. When I first started 'on the bright side' the Sun was very busy, with lots of spots, filaments and breath-taking proms. That is not the case these days. ?? However, Ha always has something to offer and we have just witnessed a very large sunspot cross the surface - which may re-appear if it hasn't decayed too much going round the far side.

2) Don't worry too much about different EPs - concentrate your efforts more on tuning and focusing - the latter is critical and it can be very, very tricky to hit exactly the right spot (no pun). I had a lot of soul searching when I acquired my Lunt, which didn't seem to be performing as well as my SM40. But I got an unusually long session last week and after a lot of faffing around it finally sang to me! ???

Dont despair, you'll get there, too. Just be aware that the Big Fella's having a wee snooze at present. ??

Oh man I hope this is the case.  IF so then it will be no problem.  I can wait and be patient.  Besides we have the eclipse to look forward to.  I caught what appeared to be a minor flare.  Perhaps the same one Cotterless45 up there got.

*I just read that a minimum can be from just a year to 30-100+ years... :*(

I at least want to be able to see granulation.  Which right now, I can't.  The much cheaper Coronado my coworker has gives a great clear view of that which makes my wallet burn.

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21 hours ago, DIGITALid said:

A quick background.

I had previously spent my fair share of time in observatories and looking through a few telescopes.  As an adult I FINALLY got a 6" Dob that I can view some distant objects with.  It was exciting that first time I accidentally came across the Orion Nebula.  That moment was awesome.  Nothing compared to the goosebumps I got in the hot sun when a coworker allowed me to look through the eyepiece of his Coronado PST for the first time.  I had NEVER seen anything like that.  The detail in the sun was very impressive.

I watched the price on that telescope inexplicably increase and never come back down.  I did my research.  I waited years!  Finally I decided to plunk down the cash for the Lunt LS50THa.  I got the B600 filter because I wanted to be able to take pictures at some point.

I spent about an hour today with a clear sky tracking the sun. (I'm working on saving for a better tripod and mount.)  So far... I am not feeling the $1,000 worth of a view I was hoping for.  I could BARELY make out ANY detail the surface.  When I could, it was only visible in one or two areas.  There was a dark areas on what to me as I faced the sun setting on the West top right and bottom left.  But it did not appear at all like what I saw through the much cheaper PST.  I HOPE its something I am doing wrong.  I tried a variety of different eyepieces.

I hope it gets better. :(

I have also waited a long time to get a Solar Scope and have nearly saved up the money for the one I want, a Lunt 50 with 6mm BF. I keep reading of people who see almost no surface detail in one Solar Scope and loads of decent contrast surface detail on other Solar scopes (all being Single Stacked), for example I read a review on Amazon on the PST and it described plenty of detail and surface texture visible, but I was offered one PST second hand recently where the guy had basically never seen any surface detail since buying it new, a terrible shame.

I have seen where there are various USA dealers who can sell me a PST for 1/2 the money of a UK sourced one and many times I have thought about chancing my arm (422 GBP / 549 USD instead of 880 GBP) but the PST cannot be automated for remote focus and tuning, whereas the Lunt 50 can, which is something I really want. I did see through an 80mm Lunt Single Stacked recently and was staggered by the amount of good contrast surface detail present (looking like iron filings), easily visible. But there are just too many reports of bad Solar scopes of Lunt and Coronado brands (look recently in the Solar section on CN forums for bad Lunt 50's) to risk buying a USA sourced one.

So I am going to be buying a Lunt 50 from FLO shortly (any chance of a 10 per cent off sale haha). I have seen a topic on here where FLO allowed some guy to have a replacement OTA if the first one doesn't perform as it should. I no longer care if it costs more to buy from UK where I am, I want peace of mind. The thought of having to send an OTA giving no surface detail or god forbid a decontacted Etalon back to a USA dealer horrifies me.

Hope you get a decent performing one. Let us know what happens! Have you contacted Lunt to see what they have to say (I see you are in USA) ?

Regards,

AG

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4 minutes ago, Live_Steam_Mad said:

Hope you get a decent performing one. Let us know what happens! Have you contacted Lunt to see what they have to say (I see you are in USA) ?

Hey thanks for your reply.  Yes I'm starting to worry I got a lemon.  I uploaded what I was able to see the first day here.  You can see a flare and barely make out some dark areas.

 

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Looks OK....

what camera were you using???

To get best results you need a mono fast frame camera like the ASI 174 or similar.

You can then acquire an AVI of a few hundred frames and use those to provide a detailed image with software like Registax.

 

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Tuning the etalon can be tricky. A prominence (not a flare, and that is quite a sizeable one) like you captured there will show over a slightly wider range than the surface detail in my experience. Focus is also critical. To me, the fact that you could tune the etalon to get a prominence suggests the tuning mechanism is not leaky.

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11 hours ago, Merlin66 said:

what camera were you using???

I just put my iPhone 7 plus up to the eyepiece to capture that.

I have yet to be able to see anything like that anymore.  I have to turn the pressure tuner all the way down and I don't see any detail anymore.  That photo was taken on the first day.  The second day I couldn't see any detail at all.

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11 hours ago, michael.h.f.wilkinson said:

Tuning the etalon can be tricky. A prominence (not a flare, and that is quite a sizeable one) like you captured there will show over a slightly wider range than the surface detail in my experience. Focus is also critical. To me, the fact that you could tune the etalon to get a prominence suggests the tuning mechanism is not leaky.

Prominence.  Got it.  I'm still a super noob.  I believe the pressure tuner was all the way in at this point.  The first day I saw a hint of some surface detail but now I can't.  The resistance starts about halfway down and I can't see anything until I turn it all the way in.  I might see a tiny hint of darkness where a dark area would be.  Nothing near what I saw that first day.  I will keep trying and tuning.  I DID notice however when I received it that the tuner had some visible scratches on it and the thread had black and brown particles in it.  I sent a picture to B&H photo and they offered me an RMA.  But I would most likely miss the Eclipse.  I have a predicament now. :(

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It is a bit fiddly to get results with Lunt but you can see your tuning is working focusing is key also and the right eyepice can make big difference also you don't normally get surface detail and proms together you will find the sweet spot between both keep practicing also are you using a black cloth or towel over your head when viewing makes all the difference my Lunt  60 is almost screwed in mostly for detail my 50 was the same also 

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28 minutes ago, garryblueboy said:

It is a bit fiddly to get results with Lunt but you can see your tuning is working focusing is key also and the right eyepice can make big difference also you don't normally get surface detail and proms together you will find the sweet spot between both keep practicing also are you using a black cloth or towel over your head when viewing makes all the difference my Lunt  60 is almost screwed in mostly for detail my 50 was the same also 

I'll settle for either or.  But I don't have a clear view of the surface detail at all anymore and it seems to start improving right when I hit the bottom of the pressure tuner.  Others online seem to hit that sweet spot with a few lines of thread still left.  I am using a black cover to shield from stray light.  I will keep trying.  Thank you.

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I took it outside again right now.  Ran through the steps.  Removing the pressure tuner completely and putting it back on.  When I got to as tight as I could go I saw like 2-3 small filaments shooting out of the top of the sun.  But within 10 seconds, they just dimmed to black and all the detail vanished.  (Without me touching the scope at all.)

Filament 7-27-17.jpg

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4 minutes ago, knobby said:

You could try putting the O ring on the 1st slot, and checking for debris in the pressure cell, also spreading the grease in there around evenly might help.

Oh SNAP that sounds like a great idea!  I was looking in there and I did see an orange/red ring and also noticed what appeared to be an empty slot before it.  I see fingerprints in there already and gray smudges.  I am seriously thinking B&H sold me a used one.

This is an image of it right out of the box.  The edge also had a visible chip in the metal.

IMG_0159.JPG

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Knobby's advice is sound. It is losing pressure. And fast by the sounds of it. 

 

The view should never go away. Daytime seeing is fickle though and there could be a sweet spot in that area. So make sure you move the sun around the blocking filter and check for a decent amount of time about whether or not it is holding pressure.

 

If you keep repeating it, that is rethreading the pressure tuner on and off again, and it doesn't get fixed by regressing and a simple o ring -  you might have a serious problem. 

 

Sometimes all that it takes is a new o ring. If it is preowned and/or has a old o ring , simply changing it is all that is required. A cheap easy fix. 

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5 minutes ago, Tyson M said:

Sometimes all that it takes is a new o ring. If it is preowned and/or has a old o ring , simply changing it is all that is required. A cheap easy fix. 

I hope that's the case.  I'm going to try to move the O-ring right now before sunset.  Thanks.

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it's under warranty id send it back at what they cost you want a good one but as Knobby said try moving and regressing the o ring 

your image should not fade that means it loosing pressure hopefully just a regrease and o ring placement 

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11 hours ago, garryblueboy said:

it's under warranty id send it back at what they cost you want a good one but as Knobby said try moving and regressing the o ring 

your image should not fade that means it loosing pressure hopefully just a regrease and o ring placement 

Yeah I'm definitely (unfortunately) opting for a return. :( I moved the o-ring and could not get the pressure tuner inserted well at all it took a level of force I was NOT comfortable with applying frequently.  Worse yet in the hot sun.  So I put the o-ring back and will be returning the scope. :(  It idid not improve my viewing at all even then.

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This is why I went with a tilt tune. I came across too many niggles with the pressure tune reviews and given how much more they cost over the tilt tune it was a no brainer.

There seem to be a few people disappointed with the views through lunt's at the moment and it is a shame as they are great scopes. I think the problem is you buy a new scope you automatically expect it to work perfect straight out the box and with the whole pressure tune thing faults are not always going to be that obvious if you have a slight leak.

It is worth noting though that the seeing and transparency conditions play a huge part in the amount of detail that can be visible. Oddly cloud passing over in front of the solar disc can sometimes add to the amount of surface detail that can be seen. It's as if it brings another level of contrast to the views. High level haze on the other hand has totally the opposite effect and can make the views quite flat and disappointing. As others have mentioned though there has to be something going on for you to observe and the sun has started to settle down in to the solar minimum.

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I have had a Lunt 50 for a couple of years and never had any issues with it. I find the best way to tune it is to put in a relatively low power eyepiece (15mm plossl?) so that the whole disk is in the central sweet spot of the FOV and then tune slowly until you can see prominences around the disk (assuming they are there). Once they start to appear just slowly move the tuner in an out until you find the optimum position where the prominences at their brightest. Assuming it is a clear day, you should now be able to see surface detail that is not too dissimilar to this picture...

597cc61f680a5_ScreenShot2017-07-29at18_26_23.png.269fc866695ff178d8771851b049e5d4.png

I agree with others that it is likely that your tuner is not properly sealed but hopefully the above gives you an expectation of what these scopes can deliver.

Good luck!

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