My version of John`s halogen-led conversion!

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Gasman
Posts: 153
Joined: Sat Jan 09, 2016 1:36 pm
Location: North East UK

My version of John`s halogen-led conversion!

#1 Post by Gasman » Thu Sep 29, 2016 7:25 pm

Hi guys
Finally got all the bits and bobs I needed to have a go at converting my Leitz scope from Halogen to led illumination (you weren`t joking about the slow boat from China John :o ).
It has come about more of necessity than just a trial really as the mini supernova (ie halogen bulb) was warming up my desk a bit too much for comfort as unlike John`s its placed in a lamp housing at the back of the scope with the bulb literally millimeters from the wood desk top.
I wanted to do a minimum alteration of the scope just in case I needed to make it Halogen lit again. I was tempted to install the bulb under the diaphragm like John`s conversion but thought I`d try it in the existing housing first and it seems to work perfectly plus I really didn`t want to remove all the lens/mirror/prism assembly.
My new setup seems to work brilliantly and very pleased with it. If anything its a Tad less bright than the Halogen but hardly worth bothering with.
I did also notice using the x4 objective that a dark ring is noticable on the outside of the FOV regardless of how bright the dimmer unit is or how much the diaphragm or condenser is adjusted but no problem with any other objectives.
Big thanks to John (mrsonchus) for his excellent instructions.
regards
Steve
Ps apologies for the order of the images, I think I should have started with the last one first ??
Attachments
Out with the Dremmel to make a slot in the Keyhole fitting 0.5" futher back, seems more central no.
Out with the Dremmel to make a slot in the Keyhole fitting 0.5" futher back, seems more central no.
bulbafter.jpg (176.21 KiB) Viewed 4956 times
The new bulb was just off centre by about 0.5" so not all the light went to the mirror/lens assembly.
The new bulb was just off centre by about 0.5" so not all the light went to the mirror/lens assembly.
bulbbefore.jpg (173.15 KiB) Viewed 4956 times
Already had a diffuser disc in place.
Already had a diffuser disc in place.
rearhousinglens.jpg (159.21 KiB) Viewed 4956 times
The bulb easily replaced the Halogen bulb.
The bulb easily replaced the Halogen bulb.
bulbtohousing.jpg (213.96 KiB) Viewed 4956 times
Shot with base cover off.
Shot with base cover off.
underbase.jpg (205.13 KiB) Viewed 4956 times

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mrsonchus
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Location: Cumbria, UK

Re: My version of John`s halogen-led conversion!

#2 Post by mrsonchus » Thu Sep 29, 2016 10:55 pm

Aha! Nicely done old chap - that's the kit!

I too fitted mine as as easy-to-remove install. I could convert it back to it's original 20W Halogen in about 45 minutes. I'm pretty sure the SMD 'bulb' is indeed 3W.

Nice job - and so cheap & easy to do. :)
John B

billbillt
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Joined: Mon Nov 10, 2014 10:01 pm

Re: My version of John`s halogen-led conversion!

#3 Post by billbillt » Fri Sep 30, 2016 12:53 pm

Yes.. This is a neat and cheap way to upgrade to LED... Well done friends!..

BillT

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75RR
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Location: Estepona, Spain

Re: My version of John`s halogen-led conversion!

#4 Post by 75RR » Fri Sep 30, 2016 2:10 pm

I wanted to do a minimum alteration of the scope just in case I needed to make it Halogen lit again. I was tempted to install the bulb under the diaphragm like John`s conversion but thought I`d try it in the existing housing first and it seems to work perfectly plus I really didn`t want to remove all the lens/mirror/prism assembly.
If you have kept the original assembly and placed the LED in the same position as the original bulb's filament,
then you should be able to focus it and therefore achieve Köhler.
If ever you require a brighter light (more than the halogen) then a single LED bulb such as the Cree XM-L should do it.
The LED is 5mm x 5mm which should be close to the size of the halogen bulb's filament.
http://www.cree.com/LED-Components-and- ... /XLamp-XML

Image
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

Gasman
Posts: 153
Joined: Sat Jan 09, 2016 1:36 pm
Location: North East UK

Re: My version of John`s halogen-led conversion!

#5 Post by Gasman » Fri Sep 30, 2016 4:24 pm

Just realised I forgot to flip up the condenser lens when using x4 ,FOV fine now Doh!! :oops:
Thanks for the info
Steve

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75RR
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Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: My version of John`s halogen-led conversion!

#6 Post by 75RR » Fri Sep 30, 2016 4:37 pm

Just realised I forgot to flip up the condenser lens when using x4 ,FOV fine now Doh!!
I have found that slightly embarrassing solutions are the cheapest and quickest to implement,
so I have not just learned to live with these little slips; I welcome them!
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

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