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A terrible start with the Lunt LS60THa


swag72

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I have a Lunt LS600THa, bought specifically for my Mum as she wanted to do some solar observing, but of course I got roped in to trying to set it up :) To say the whole thing was an abject failure is an understatement and I wonder if the whole thing has been an expensive mistake...... Underwhelming and disappointed is the current feeling. I hope it's down to my utter beginner status in the visual field and also solar.

I'd be grateful if you could bear with my tale of woe and perhaps confirm that it will only get better :( 

Firstly I have to say that I didn't have the right kit. We were mounting it on a camera tripod and Manfrotto ball head. The sun was impossible to find (almost) and the views through the 25mm EP were dubious at best......... not a full circle depending on how you moved your head, full of eye lash shadows...... This visual lark sucks :(  Also I have to say that I was surprised at how poor the focuser was on the scope...... I did expect better.

So to combat this we're getting an iOptron CubePro so that we can track it. A Sol searcher so that we can find the damn thing and a 18mm AA Lightwave EP with a 68 degree FOV and 20mm eye relief.

In your experience will this make a difference or am I wasting money now and should just give up on the idea ?

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I am interested in this because I am also thinking of getting a Lunt 60 - indeed I came very close to buying one at the IAS in Warwick at the weekend.  I cannot help with the Lunt, however, I have done some solar viewing (and a bit of imaging) with a Quark in my ED80.  Like you I find it quite difficult to find the sun sometimes.  The Sol Searcher helps a lot - indeed I would say that, for me, it is essential.  Mine is not quite centred properly but I have learned where the white circle needs to be, to put the sun in the eyepiece.  I use my mount for tracking, but was wondering about doing it manually with a Vixen Porta mount or something similar.  

If you are having problems with the 25mm EP have you tried something wider?  I just use a 'standard' 40mm plossl that came with one of my scopes.  I hope you get it working - I still find the views of the Sun that you can get in these Ha scopes quite spectacular.  

Steve

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Ha observing can be a little finicky to start with if you haven't had previous experience at the eye piece.

The trouble is I think you have an etalon and a small blocking filter for the light to pass through so this makes the light cone smaller than one would be used to in a night time scope for instance. This is no problem as the scope is after all intended for only one target in mind 'the sun' but it does make it difficult for first time users to position themselves so as to avoid black outs. I over come this problem by using BST starguiders as they have screw up eye guards that allow my eye to rest in a comfortable position with no worries of hovering of the spot. I also found that they perform very well with the Lunt and don't cost the earth. Lunt themselves recommend sticking to simpler designs like plossl and the BST's are that.

The LS60tha is a heavy weight for it's size so unless you have a high end camera tripod I would recommend investing in either an AZ3 or AZ4. Tracking the sun smoothly is key to keeping that etalon & blocking filter lined up so the light reaches centre view of your eyepiece.

As for the views I will say they can be a little underwhelming to those who see images on the forum or in glossy magazines. I think we often take for granted just how dangerous it is to look at the sun and just how difficult and expensive it is to do so in hydrogen alpha. I think people have to be realistic in their expectations and accept just as DSO's reveal themselves as not much more than a fuzzy blobs in a 60mm scope not to expect SOHO images of the sun in one. Yes it can be a little disheartening when you pay out such a lot of money on a dedicated solar scope to see a relatively small return but it is what it is and unless your DIY savvy and are prepared to take on a PST mod then your not really going to get much more for your money.

A sol searcher is essential for finding the sun in a Ha scope and useful for those observing in WL also. The sweet spot for eyepieces seems to be around 11 - 13mm in the LS50 & LS60's.

One thing I will say it Ha observing is very reliant on good seeing and transparency. Any haze or turbulence will refrain those subtler details from shining through. It really is quite shocking how you can get a beautiful clear blue sky and the views are bland yet you get a cloud dodging day with a stiff breeze and the contrast adds another dimension.

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Is the scope a the pressure tuned or tilt tuned model? 

The tripod setup would have scared the daylights out of me, a sturdy tripod will make all the difference & you 100% must need a solar finder to easily locate the sun. Sol finders are fantastic. 

I would get an eyepiece with less glass elements,  I used a few fancy eyepieces with the 50mm Lunt and they were very poor for the job.  If less eye relief is an option then the 20mm & 15mm TV Plossls are flawless in this application.  They blew all the other EP's I tried out the water & by a mile.  They allow exceptional Ha viewing in sharpness & light transmission.  You don't need wide-field EP's for solar, if anything it makes getting the sweet even more tricky.    I manually follow the disc with ease & as you are planing to auto track the disc it should be easy to keep the sweet spot sweet.

I am sure others will chip in with their personal experience and tips.  

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Do you think that the EP selection that I was looking at is not the best? http://www.altairastro.com/18mm-altair-lightwave-premium-long-eye-relief-eyepiece-68-fov.html this is the EP I was recommended. If you suggest anything else it need to come from AA as that's where the CubePro is coming from.

I *think* it's a pressure tuned model, but I don't really know. It's got that little twiddle wheel on the top.

I don't want any 'blackouts' and eye lashes through the EP - My eye lashes have a minimal amount of interest for me :)

@gnomus - There was ZERO spectacular about what I managed to glimpse. It was utter pants :(

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You want to use straight forward basic plossl eyepieces of good quality to get the best from the Lunt. I went with http://stores.ebay.co.uk/Skys-the-Limit-Astro-and-Optical/BST-Starguider-ED-/_i.html?_fsub=2568750014 as they are more comfortable to use and have better eye relief over traditional plossl. They have screw up eye guards for better eye position to avoid black outs. The lightwaves have too complicated a design and way more FOV than your going to use as even in the 60° BST you will get vignetting.

You have the tilt tune model which once you get enough time with the sun you'll be able to fine tune the band allowing for the best detail (seeing dependant). If you go totally off band you can also observe the suns surface similar to white light views.

I think TBH you need more time with the scope set up on a nice mount with more suitable eyepieces. Have a little patience :)

 

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Sorry to hear about your struggles Sara. I haven't used the Lunt but I've used a similar Coronado Solarmax 60 (single stack) a few times. I'm a very inexperienced visual observer but I found the views quite spectacular.

A proper solar finder will help a great deal. The first couple times I struggled to find the Sun but now I've worked it out I can find it in seconds - when off target it shows a big beam-shaped reflection, I just unclutch and follow it. For tracking my EQ3 with RA motor does the job. I just align north using a compass and the Sun stays in view for a long time, this is ok for imaging too. On a fixed tripod I agree it's all a pain.

For viewing, I either hold a hat in the way or put a towel over my head to stop the glare from intruding. Fiddling with the etalon a little I found a setting granulation, sunspots and prominences could all be viewed together, I've usually left it alone after that. Personally, I've mostly used wide-angle eyepieces so I could view the entire disk at once, I certainly haven't pushed the instrument to its potential.

Hope your next session is a bit less frustrating.

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Hi, Sara. I, too, am sorry to read about your travails. I'm sure things will improve.

As spaceboy points out, you have a tilt-tune model - the 'twiddle wheel' tilts the etalon system to achieve optimum performance.

I use a 12mm Cemax eyepiece mostly, as well as TV plossls, which are put to good use with the Quark as well.

It may seem fiddly at first but if you spend time carefully tuning the scope you WILL get great views. At present the Big Fella is in a quiet kind of humour and solar features are not as plentiful as they sometimes can be. Also your single stack will major on prominences, rather than spots. You will see the spots and associated plage but, while interesting in Ha, I think white light gives a better return on these features.

You will already know that visual observing will never produce what you get in imaging ... but it's worth reassuring you that you will get views that are definitely not 'pants'. Stick with it and try to get through the frustration of faffing around and it will be worthwhile for you and your mum.

As for difficulty in finding the sun, I feel a solar finder is worth its weight in gold (see my sig!).

We're all rooting for you. ??

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I don't think I'm qualified to 'recommend' eyepieces - there are Loungers with vastly more experience than I. As earlier, I mostly use a Cemax 12mm; this gives me full disc and pleasant framing. Simple EPs are best, as has been mentioned before.

Why not drop a line to FLO and ask for some advice there?

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1 hour ago, swag72 said:

Do you think that the EP selection that I was looking at is not the best? http://www.altairastro.com/18mm-altair-lightwave-premium-long-eye-relief-eyepiece-68-fov.html this is the EP I was recommended. If you suggest anything else it need to come from AA as that's where the CubePro is coming from.

I *think* it's a pressure tuned model, but I don't really know. It's got that little twiddle wheel on the top.

I don't want any 'blackouts' and eye lashes through the EP - My eye lashes have a minimal amount of interest for me :)

@gnomus - There was ZERO spectacular about what I managed to glimpse. It was utter pants :(

No that is the tilt-tune model.  The pressure-tuned model has a big knob sticking out of the side of the scope that you turn to tune.  I found it a little on the stiff side when I got my hands on one in Warwick.  I am told that some folks knock the sun out of the FOV when tuning the pressure-tuned model.  (Needless to say, that is the one I am after.)

 

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A better mount makes all the difference, as does a sol-searcher. I have used a range of EPs ranging from a TV 25mm Plossl (20mm eye relief) to Pentax XWs. Currently I use a zoom EP with 18.5-19mm eye relief, and a few Vixen SLVs. I had very good results with the Pentax XF 8.5mm, very comfortable. I replaced it for a Delos 8mm which also works well. Solar observing is tricky because the image through the scope is a lot dimmer. I find wearing a hat (or cap) to keep the sun out of my eyes works very well. It also helps to be seated.

Given that you are using a tilt-tuned system, I wonder if you actually spotted the sun, or a ghost image caused by reflections in the optical path. I have heard of people desperately trying to focus on this ghost, and being totally frustrated by the lack of detail. Once they got the actual disk of the sun into focus, and got the tuning right, they had to collect their lower jaw from the floor.

Best of luck sorting it out

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1 minute ago, michael.h.f.wilkinson said:

A better mount makes all the difference, as does a sol-searcher. I have used a range of EPs ranging from a TV 25mm Plossl (20mm eye relief) to Pentax XWs. Currently I use a zoom EP with 18.5-19mm eye relief, and a few Vixen SLVs. I had very good results with the Pentax XF 8.5mm, very comfortable. I replaced it for a Delos 8mm which also works well. Solar observing is tricky because the image through the scope is a lot dimmer. I find wearing a hat (or cap) to keep the sun out of my eyes works very well. It also helps to be seated.

Given that you are using a tilt-tuned system, I wonder if you actually spotted the sun, or a ghost image caused by reflections in the optical path. I have heard of people desperately trying to focus on this ghost, and being totally frustrated by the lack of detail. Once they got the actual disk of the sun into focus, and got the tuning right, they had to collect their lower jaw from the floor.

Best of luck sorting it out

Yes.  I have certainly tried focussing on that ghost/reflection.  Now that is very underwhelming.

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Hi Sara sorry to hear about your predicament.  I used to have the Lunt 50 and now have the Lunt 60 pressure tuned model, pictures attached (you can also see the Sol Searcher in the case).  I am not familiar with the tilt adjusted model.  The pressure tuner allows the viewer to 'tune in' the etalon to bring out superior detail on the photosphere.  There are different sweet spots depending upon whether you wish to view surface detail, prominences or filaments. I really enjoy solar viewing and imaging and the Lunt 60 can give excellent views so I encourage you to persist.  I have tried various eyepiece combinations.  I have settled on two EPs which give great views for me.  They are my ES 14mm and ES 20mm 82' FOV.  The worst performers were the Baader Hyperions due to their shocking lack of eye relief. The most important accessory however is the 'Photographers Hood' that my daughter made for me out of some black cloth remnant.  It velcro fastens around the OTA and then I put it over my head and the whole experience becomes much more satisfying.

IMG_0328.JPGIMG_0327.JPG

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16 minutes ago, gnomus said:

Yes.  I have certainly tried focussing on that ghost/reflection.  Now that is very underwhelming.

This was my first thought as well, so easy to make this mistake, specially without a solar finder! Properly focused and tuned, the image should be similar in detail to those shown on GONG with somewhat less contrast. For single eye viewing I use a Seben 8-24 zoom eyepiece, works well and is more convenient. Solar telescope use is rather like first time night time imaging, bit of a learning curve!.  :icon_biggrin:

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I have done a bit of solar in the past Sara and my comments are that I think you would find it virtually impossible to do on a ball head, it's bad enough find it with a controllable EQ Mount.

One thing I found invaluable was a cheap little gadget for locating the sun.  It was a bit like this, only mine has a "stalk" on the front so you can see a shadow, when there is no shadow at all you are pointing at the sun.

ss_dphq.jpg&f=1

I also experienced a ghost reflection as described above.  Imaging the sun I found focus to be difficult as the surface is bubbling all the time.  

Carole 

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Thanks for the thoughts and comments - They are much appreciated.

@carastro - I've ordered a sol searcher so I should be able to find the sun in the future. My Mum and husband couldn't believe it when I said at the start the hardest thing would be to actually find the sun to start off with! They thought as it's a big ball in the sky it would be easy! 

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you can look down the diagonal with no eyepiece in to find the sun. when it goes bright red, it should be close.

you can also use the shadow method for initial alignment. stand to the side of the scope and when the shadow is round then you are close.

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I made a sol searcher by copying an idea of Helen's but now you have one ordered you have that covered.

I don't believe there is anything underwhelming about the views this scope gives. You see proms nicely when they are there, and solar surface granulation, filaments, sunspots and plages. I never had much use for the tuner, though. I suggest you start by finding the extreme position which gives you the proms and granulation rather than the other which gives you a flat red disk and very dark sunspots (the white light view only red.) And I'd leave it there at the proms extreme position. I found it did precious little other than dim the proms.

For an EP I used a 10mm TV Radian, mostly. This has long eye relief but an adjustable cup which you position to suit your own eye. I found little point in upping the magnification though some peple prefer a wder and brighter view from around 15mm.

The other thing to remember is that the sun is very variable and has dull days and exciting ones. In the 11/22 year cycle this may not be the best time to start your solar career, but there will be good days. It's also more interesting if you read up on the astrophysics of the sun. It doesn't have to be mathematical or difficult, just conceptual.

Olly

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10 minutes ago, ollypenrice said:

I don't believe there is anything underwhelming about the views this scope gives. You see proms nicely when they are there, and solar surface granulation, filaments, sunspots and plages.

I was clearly doing something wrong!

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I'd agree with the zoom idea as this will give you more flexibility. 

With my 60mm pst mod I find an 11mm Delite works well so something with a magnification of about 50x would be OK. Plossls and orthos are excellent for solar in general. More aperture does really show though and the view through my 100mm PST mod is dramatically different in terms of resolution/detail. The scope will give good results as described above but do remember that you are after all using a scope of 50mm aperture.

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