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Two tasty Lunts on ABS


DrRobin

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The first is a Lunt 60 with B600 blocking filter, it is the non pressure tuner version, but still looks good value at £850. B600 is a little small for large chip cameras, but would be fine for a DMK21 or barlowed DMK31/41.

Second up is a Lunt35 deluxe, again with B600 filter for £575. I am slightly interested in this as a compact travel scope as I could swap my B1200 filter in to it. Trouble is if I take my Merlin mount I might as well take my Lunt60, so I am not sure. If I could find a small motorised mount I might go for it.

Robin

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Nice heads up, Robin. I've thought about a PST but decided my SolarMax 60 is small enough for me, though I guess I save space using non-motorized mount.

Steve, are you going single or double stacked?

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Nice heads up, Robin. I've thought about a PST but decided my SolarMax 60 is small enough for me, though I guess I save space using non-motorized mount.

Do you image with the non motorised mount?

That's one of the things holding me back from using the pst mod.

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Do you image with the non motorised mount?

That's one of the things holding me back from using the pst mod.

Yes, I do image with the non-motorised mount quite a lot, I must get more H-a images processed! I normally use a HEQ5 at home but use a non-motorised mini Giro on a Manfrotto tripod during lunch at work or on holiday or when it's handy at home.

With my SolarMax 60 (400mm focal length - shorter than the Lunt 60, I think?) and my camera's 1/1.8" sensor, I can get about 1,700 frames at prime focus (26FPS) of a full disc as the Sun drifts over the sensor. I often use a 1.6x Barlow too and again take about 1700 frames, but I have to do four tiles for that. A 2x Barlow is just about do-able for some smaller features, but is a bit of a pain, so I normally stay at 1.6x max.

At home with the HEQ5 I like to image with a 2.5x Barlow, so I miss that a bit with the non-motorized. But just happy I can grab shots during lunch or on hols :laugh:

Ideally I would always use tracking as there is some drift through the sweet spot with the non-motorised, but sometimes practical wins over ideal!

I use a single stack for imaging. I don't know if a double stack (or a PST mod?) would have more of a sweet spot issue with the drift.

These shots were using the non-motorized mount (I went a bit mad with the blue in the first one :grin:):

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That is a very nice close up Luke.

I mostly use a Merlin GOTO mount for solar observing and intend to take it with my Lunt DS on hols this summer. The scope, DS, Camera, laptop and iPad takes up most of my hand luggage allowance. The Merlin, plus base and recharageble AA cells go in the suit case. Last Xmas I took my ST80 and Lunt wedge with a manual tripod and no tracking, it was hard work and holidays are supposed to be about fun right?

I keep looking at Astrotrak, but with the counter weights and trod it looks as heavy as my Merlin mount so where is the advantage?

Steve, my PST was second hand, as is my ST80, together with my HEQ5, EQ6 (both now gone) and Avalon Uno. I should mention that my Quattro 8", together with all of my cameras except my DMK41 and 600D were all purchased second hand. There are some good deals out there. I didn't realise that a basic Lunt 60 was £1,100, thought they were a bit more than that.

Robin

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Don't worry SB, Lunt 60 with tilt tuning and B600 is currently £1449. No idea where £1,100 comes from?

I would love to set up a semi automated solar Ha scope and a Lunt 60 tilt would be ideal. Pressure tuner, would be no good without the digital interface (£700) as it would need too much fiddling with. Hmm maybe, sorry MrsDrRobin is in earshot, so maybe not?

Robin

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Whilst I appreciate that there are good deals to be had with 2nd hand items there are plenty of chances for disappointment with no comebacks.

I just prefer to have new kit from my trusted supplier ...  :smiley:

I've always been this way , and if I want an item and can afford it I have it , if I don't have the money I go without ,and I don't do that credit card thing , I've never had one ...  :p

I'm quite happy recording the Sun in "whitelight" to the best of my ability on a limited budget ...  :grin:

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My Lunt 60 in single stack has no noticeable 'Sweetspot', but put a double stack on it and it is very noticeable. A full disc double stack is possible, but the DS has to be rotated and held in exactly the right spot. However, put a 1.5x Barlow on it and the images are superb. I was a bit disappointed when I first got my double stack, so much so I considered sending I back until I realised that everyone seems to go through the same thing and it needs very careful rotation and tuning to make it work. Pity they don't mention this in the tuning/setup notes.

Robin

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Yes, I do image with the non-motorised mount quite a lot, I must get more H-a images processed! I normally use a HEQ5 at home but use a non-motorised mini Giro on a Manfrotto tripod during lunch at work or on holiday or when it's handy at home.

With my SolarMax 60 (400mm focal length - shorter than the Lunt 60, I think?) and my camera's 1/1.8" sensor, I can get about 1,700 frames at prime focus (26FPS) of a full disc as the Sun drifts over the sensor. I often use a 1.6x Barlow too and again take about 1700 frames, but I have to do four tiles for that. A 2x Barlow is just about do-able for some smaller features, but is a bit of a pain, so I normally stay at 1.6x max.

At home with the HEQ5 I like to image with a 2.5x Barlow, so I miss that a bit with the non-motorized. But just happy I can grab shots during lunch or on hols :laugh:

Ideally I would always use tracking as there is some drift through the sweet spot with the non-motorised, but sometimes practical wins over ideal!

I use a single stack for imaging. I don't know if a double stack (or a PST mod?) would have more of a sweet spot issue with the drift.

These shots were using the non-motorized mount (I went a bit mad with the blue in the first one :grin:):

Thanks for the detailed reply and those pics are great.

I'm guessing as long as you have can get a full disc then the principle is the same. The sweet spot on mine is in a stupid position that would make getting a clean disc difficult, I'd have to check on that.

I do have a motor drive for the EQ2 but could never get the tracking right, maybe I should work that out.

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My Lunt 60 in single stack has no noticeable 'Sweetspot', but put a double stack on it and it is very noticeable. A full disc double stack is possible, but the DS has to be rotated and held in exactly the right spot. However, put a 1.5x Barlow on it and the images are superb. I was a bit disappointed when I first got my double stack, so much so I considered sending I back until I realised that everyone seems to go through the same thing and it needs very careful rotation and tuning to make it work. Pity they don't mention this in the tuning/setup notes.

Robin

I'd echo that. The DS takes a LOT more skill to get the best from it. It does give a more "contrasty" image, but it dims the image down a lot. The sweetspot is very, very noticeable and it takes time to "clock" it around to get the best position.

How do you lock your DS into the correct position? I have to leave mine a bit loose on the threads which means that there's play in it which can affect the image.

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I use an adapter from Telescope Service.  It is actually meant to rotate a focuser but is threaded with an M90 thread on each side, the same thread as used on the Lunts.  I just get it rotated to the correct spot and lock it in place with the three grub screws.  The adapter is made in two parts, the grub screws lock up on a dovetail, so it does go back level and in the same place.

After several sessions, I realised I could leave the DS in place, tune the main Etalon and then fine tune both.  I did try removing the DS, tune the main Etalon and then add the DS back in, but it didn't make much difference.  With two to tune you can end up going round in circles if you are not careful.

Link to the adapter below.  Sorry the description page is only in German, but the you can use an online translator.

http://www.teleskop-express.de/shop/product_info.php/language/de/info/p4295_.html

I am really surprised that Lunt don't sell something like this, having the DS loose, does mean it tilts on the threads.  I did mention it to Lunt at Astrofest, said I used a TS adapter and the guy even seemed to know what I used.

At 90 Euro it isn't exactly cheap, but given how much a 60mm DS costs, it does provide a very solid mounting.

Robin

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Steve,

Your white light images are excellent and I understand your reluctance to buy an expensive scope/astro item on the second hand market, it could easily go wrong, but my experience (to date) has been good both from here and ABS.  Like you if I can't afford it I do without, especially for something like a hobby.  I do use a card to purchase, but it is more for convenience than anything else.

Now if a SF100 came up from a trusted seller, hmm, if I still had a grandmother I might be tempted to sell or part ex her.

Robin

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I use an adapter from Telescope Service.  It is actually meant to rotate a focuser but is threaded with an M90 thread on each side, the same thread as used on the Lunts.  I just get it rotated to the correct spot and lock it in place with the three grub screws.  The adapter is made in two parts, the grub screws lock up on a dovetail, so it does go back level and in the same place.

After several sessions, I realised I could leave the DS in place, tune the main Etalon and then fine tune both.  I did try removing the DS, tune the main Etalon and then add the DS back in, but it didn't make much difference.  With two to tune you can end up going round in circles if you are not careful.

Link to the adapter below.  Sorry the description page is only in German, but the you can use an online translator.

http://www.teleskop-express.de/shop/product_info.php/language/de/info/p4295_.html

I am really surprised that Lunt don't sell something like this, having the DS loose, does mean it tilts on the threads.  I did mention it to Lunt at Astrofest, said I used a TS adapter and the guy even seemed to know what I used.

At 90 Euro it isn't exactly cheap, but given how much a 60mm DS costs, it does provide a very solid mounting.

Robin

That's a great device!

€90 is a bit salty though. <sigh> These blooming bits of turned ally sure are expensive!

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How do you lock your DS into the correct position? I have to leave mine a bit loose on the threads which means that there's play in it which can affect the image.

I place a girls elastic hairband on the threads of the DS. It acts like an 'O' ring and is just enough to take up the slack in the threads and keep the DS tight.

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