Where can I buy a bulb for my Leitz SM Lux in the UK?

[Damflask]

Where can I buy a bulb for my Leitz SM Lux in the UK?
Apologies in advance if this is an obvious question.

[billbillt]

Hi,
Remove the bulb and note down the info written on it... Then do a Google or whatever search for that info... This generally works for me... You will probably have ample choices of where to purchase... BillT

[einman]

Alternatively you can retrofit it with an LED light. Those are sold on E-bay. I did that with my Leitz Laborlux and Laborlux S.

[Damflask]

Oh really?
That's interesting. Do you have any details?

[billbillt]

Yes, the LED conversion is a very good option... I think I have only two stands here that use the original incandescent lighting... The rest I have found a way to use LED exclusively...
BillT

[gekko]

There are those who have converted their microscope to use LED or are planning to do so, and there are those who stayed with the original illumination. The former will urge you to join them and convert to LED. I, being a member of the latter group, will ask you to be cautious and take your time before you decide to convert. The microscope manufacturer has put some thought into designing the lighting system of his microscope (which, admittedly, may have involved some compromise to keep costs down). There are a few threads on this forum that describe the conversion process that you may want to look at. One thing that I think is very important: the replacement LED must fill the aperture of the condenser with light in order not to result in poor resolution (especially with the higher power objectives). The easiest way to ensure this would be to make sure that the emitting surface of the replacement LED has the same (or larger) physical dimensions than the tungsten filament, and that it is located in the same physical location as the filament, My suggestion would be to get a replacement bulb now, and use the time you save (by not embarking on a project to convert to LED) to get experience in using your microscope until you are at a point where you decide you want to convert to LED for whatever reason (lower heat being one reason, and expected working life being another). My 2-cents' worth.

[Oliver]

In response to Gekko's post concerning the size of the LED and the tungsten filament, I wonder if it is possible to use a diffuser above the LED. I once experimentally tried to use LEDs but the illumination was very uneven. You might also want do read the article "Do-it-yourself Microscope LED Illuminator" in the March 2011 issue of the magazine: http://www.microbehunter.com/microbehun ... arch-2011/, free to download.
Here several LEDs were used.

Oliver

[billbillt]

Hi oliver,
I have cut diffusers from opaque juice cartons that seem to work as well as frosted glass... I would tend to agree with gekko... Use the provided light source if at all possible... The LED system is just a viable replacement for a non-existent bulb, or one that is grossly over priced... More powerful LED's are being offered on Ebay at very low cost... They do have a very long life span when compared to incandescent bulbs, with little or no heat output... A 3 watt LED is so bright, it hurts your eyes to look directly at it...
BillT

[einman]

There are those who have converted their microscope to use LED or are planning to do so, and there are those who stayed with the original illumination. The former will urge you to join them and convert to LED. I, being a member of the latter group, will ask you to be cautious and take your time before you decide to convert. The microscope manufacturer has put some thought into designing the lighting system of his microscope (which, admittedly, may have involved some compromise to keep costs down). There are a few threads on this forum that describe the conversion process that you may want to look at. One thing that I think is very important: the replacement LED must fill the aperture of the condenser with light in order not to result in poor resolution (especially with the higher power objectives). The easiest way to ensure this would be to make sure that the emitting surface of the replacement LED has the same (or larger) physical dimensions than the tungsten filament, and that it is located in the same physical location as the filament, My suggestion would be to get a replacement bulb now, and use the time you save (by not embarking on a project to convert to LED) to get experience in using your microscope until you are at a point where you decide you want to convert to LED for whatever reason (lower heat being one reason, and expected working life being another). My 2-cents' worth.

I don't advocate one over the other. In fact depending on the LED set up it can create issues during videos. However- I have a Leitz laborlux S stand with the original halogen and the LED conversion and find the LED conversion quite pleasing to use. I can convert back to the original halogen in about 5 minutes as the original mounting holes etc are maintained and no changes are made to the stand. The LED conversions I purchased on e-bay are not inexpensive. They cost $95.00. They have more than enough brightness and fill the entire aperture with no issues. This is in part accomplished by a lens built into the illuminator which acts as a diffuser. The Leitz stand also has a diffuser built into the base. Though interestingly I have several stands of the same model and on one the diffuser was not present though it did not appear to affect the performance. When Leica/Leitz merged during the transition they may have eliminated the diffuser. Or ..it could simply have been missing though it would have been intentional as they are not easily removed.



I am far from a technical expert so you can refer to the other postings. But I will say the amount of heat is significantly less and if you spend hours viewing the heat can be intense. My AO 20 seroes gets very hot ans does the bench beneath it when I use it for long periods. I have been considering a conversion. I actually will not make the conversion if it require alteration of the stand. I like the idea of using a stand as it was originally designed at times. I am a bit nostalgic in that I want the stands to remain original or at least can be made original quickly.

For stereoscopes I greatly prefer Halogen lighting over LED. I believe it gives greater contrast.

[Damflask]

Thanks for these replies.
Much appreciated.