Lunt Mod

Frankenscope? Let's see it!***be advised that NOTHING in this forum has been safety tested and you are reading and using these posts at your own peril. blah, blah, blah... dont mess around with your eyesight when it comes to solar astronomy. Use appropriate filtration at all times...
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solarmax2016
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Lunt Mod

Post by solarmax2016 » Sat Jun 03, 2017 2:45 am

For Merlin 66

I could not download the webmaster address for some reason unknown, but am answering your request on Solarchat. The Lunt MOD finally turned out to be a success (I had my doubts at first because of high altitude jet stream perturbations since March 1 2017. Finally got some good seeing just recently.
The LUNT etalon is a cantankerous piece of hardware - the collimator has to be very close to its favoured position or you get a blurred image and I understand from Brian at Lunt that it is f/2. (Doesn't leave a lot of room to play with- a few millimetres of tolerance is all you get). You have to work out the dimensions PHYSICALLY with an ad hoc cardboard tube - positionned on the snout of the Collimator tube butted up against the black hub of the
etalon assembly behind it. I glued a mm scale to the top of the tube for ease of measurement. This is the hard part: take off your focuser assembly and with a video camera in the LUNT focuser slide the dummy cardboard tube in and out of the donor telescope tube, note the focus position on the tube looking at your monitor and allow a mm on either side for error - it's a sweat to do this because keeping the cardboard tube-Lunt assembly plus it's focuser steady and within the optical cone of light requires real dexterity - it took me about an hour to guarantee I had the right focus. When you finish this draw up a scale diagram (preferably in mm) so you can build the tube plus flange assembly. To save machine costs get Moonlight focusers to send you their extender kit -
probably you will need a 1-3/4" extender and a 1-1/4" extender plus an upper tube to complete your extension series. The tube between (same diameter as your donor tube) you have to buy from Global Engineering who supply a full range of 14 & 16 gauge anodizing grade tubing. - It costs very little to buy and ship. Don't anodize it like I did because white automotive paint reflects light better. I sent you the working diagram for the Meade 102ED - it will be
different for every brand of scope (the connecting tube being the difference, all the rest the same.I was amazed at what this MOD can do. Attached is a 2X barlow (nosepiece barlow on the DMK41AUO) in BAD seeing - just blew me away! If you need the diagram again just ask and I'll send it again. Attached is my image on a bad seeing day.

John
Attachments
May28_2017LUNTMOD2X.jpg
May28_2017LUNTMOD2X.jpg (194.46 KiB) Viewed 1024 times

solarmax2016
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Re: Lunt Mod

Post by solarmax2016 » Sat Jun 03, 2017 3:04 am

Merlin 66

Attached are two photos of the complete LUNTMOD Assembly. Good luck with it.
John
Attachments
LUNT100mmMeadeRefractor.JPG
LUNT100mmMeadeRefractor.JPG (568.95 KiB) Viewed 1020 times
LUNTMODtailpiece.JPG
LUNTMODtailpiece.JPG (439.79 KiB) Viewed 1020 times

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marktownley
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Re: Lunt Mod

Post by marktownley » Sun Jun 04, 2017 10:21 am

Nice job there!
Image
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!

solarmax2016
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Re: Lunt Mod

Post by solarmax2016 » Sun Aug 13, 2017 4:53 pm

Has anyone had any experience using a 0.5 X Focal Reducer in front of a DMK41AUO (or equivalent camera) in H-alpha photography. The kit from Williams Optics has a small 0.5X eyepiece-fitting lens along with a detachable barrel (about 1" long) that fits it. Neither component in any combination will come to focus on the nose of the camera (or any camera I have). Perhaps the camera nose (standard) is too long - I had this trouble with a stock PST and its long eyepiece holder that had to be cut off shorter to use with any camera (without a focal reducer). We need a focal reducer for Solar Eclipse shots of the full disk and its coming up soon. Thanks

John

solarmax2016
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Re: Focal Reducers and H-alpha photography

Post by solarmax2016 » Sun Aug 13, 2017 4:55 pm

Has anyone had any experience using a 0.5 X Focal Reducer in front of a DMK41AUO (or equivalent camera) in H-alpha photography. The kit from Williams Optics has a small 0.5X eyepiece-fitting lens along with a detachable barrel (about 1" long) that fits it. Neither component in any combination will come to focus on the nose of the camera (or any camera I have). Perhaps the camera nose (standard) is too long - I had this trouble with a stock PST and its long eyepiece holder that had to be cut off shorter to use with any camera (without a focal reducer). We need a focal reducer for Solar Eclipse shots of the full disk and its coming up soon. Thanks

John

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marktownley
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Re: Lunt Mod

Post by marktownley » Mon Aug 14, 2017 7:09 pm

Try it, but the sweet spot will be a lot more obvious...
Image
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!

bart1805
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Re: Lunt Mod

Post by bart1805 » Tue Aug 15, 2017 12:18 pm

You could perhaps try a short shoulderless nosepiece for the DMK. It worked for me.

bart1805
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Re: Lunt Mod

Post by bart1805 » Tue Aug 15, 2017 6:50 pm

bart1805 wrote:
Tue Aug 15, 2017 12:18 pm
You could perhaps try a short shoulderless nosepiece for the DMK. It worked for me.
Robert, I measured it for you.With the short shoulder less nosepiece I gained 4 mm of backfocus.

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