Suggestions for a DIY PZO Biolar lamphouse/illuminator

[Smokedaddy]

Need some suggestions and tutelage for a DIY lamphouse for my PZO Biolar. I'm pretty lousy with electrical/electronic stuff but willing to try. I do know how to solder. I think I'm pretty handy with tools and I am capable of machining/welding/brazing and metal fabrication etc. I'm not sure even where to start (PZO wise). Before I forget to ask, should I blacken the illumination 'tube' that's inside the base of the PZO? I have a spare Nikon 100w lamphouse, power supply, a diffuser from a Optiphot (and the holder for it) and a Optiphot filter cassette. Should I take the time to put this arrangement together? Will it work on the PZO this way? Will it be bright enough for darkfield (if I can figure out how to do DF on my PZO). Should I scrap that idea and go with something else? I purchased a 3rd party LED illuminator from some guy on eBay a year ago but got burned. He promised to make it right but I never heard back from him.

[JohnyM]

Try to mod original illuminator for LED, it's really eazy. Anything else - if you ask if it's possible - it's not.
Here are some ideas, how i moded some of illuminators:
https://get.google.com/albumarchive/110 ... XDwuQZe9qg

https://get.google.com/albumarchive/110 ... Fnp64YHPS3

Since you need no optics, all you have to do is put the LED in the proper place and provide sufficient radiator, it's very simple. You can even try to modify burnt bulb.

[Smokedaddy]

Let me backup before asking more questions about illumination modifications.

How is darkfield accomplished with the PZO Biolar using the the DIC accessories ? What is the setup procedure?

-JW:

[phil m]

It looks to me that the examples provided are lower power 200-300 lumen systems that can be retrofitted fairly easily.

However, the level of illumination required out of a rear mounted 100 watt illuminator is a whole other thing. I have used a lot of 100 watt DF systems and I have yet to be convinced that led can provide the quality of illumination required to effect high resolution DF with enough usable illumination to be valuable. The lumens needed are quite high and the output of the factory suppled bulb of one system I am familiar with, is around 3500; perfectly adequate for a 100X oil immersion DF objective , with various filtering techniques too.

No doubt companies like Leica, who are now offering led as an option on $10,000 microscopes will have it right because they are engineering the system from scratch but no one has provided me with photographic evidence that any of the commercially available retrofits or DIYs are good enough for a 100X objective. I've done about 10 conversions myself, from incident illuminators for stereo microscopes, in base illuminators for diascopic microscopes, and remote high wattage illuminators for diascopic microscopes and only the modest types of retrofits have been in any way successful, something similar to the examples JohnnyM provided.

Existing halogen systems are engineered with a lamp filament as a light source in mind and focusing that light source properly is the job of the collimating lens system. Putting in an led offers up a whole different source of light, with different angles of incidence, wavelengths of light and radiant characteristics, differing from the requirements of both the collector lens and the reflector. Theoretical lumen relationships between leds and halogen sources also go out the window and at the distance you are talking about, somewhere in the neighbourhood of 30+ cm. from light source to the condenser. The wattage required of an improperly collimated led light source may well be 30 or so.

Since your Nikon illuminator is essentially very similar in design to the 100 watt illuminator that originally sat on the rear of your Biolar, I would bet that altering that to fit your system would be much easier and the harmony between the reflector in the lamphouse and collimating lens system in the microscope base be much closer due to the very similar 100 watt halogen filament light source, than an led. The PZO may originally have been 220 but watts are watts. A 220 100 watt system puts out the same illumination as a 110 100 watt system.

To answer the question about the requirements of the Nikon retrofit in terms of the illuminator optical tube. I don't think you mentioned how much of the illuminator optics are left in the base or whether your Biolar was originally the 15 watt version or the 100 watt version?

[JohnyM]

DIC accesorries have nothing in common wih DF.
In fact, to get DF, you need to set UPI lever and analyzer to 0 and exchange condenser to one of avaiable models:
-K5C being best avaiable for oil immersion 40x + . Other models are more common but not as light efficient. IIRC with 20x and APS-C sensor you wont fill FOV.
-KFL being weird beast. It was ment for DIA fluorescence darkfield and phase contrast. Standard darkfield / brightfield slots and special phase annulis that are made from UG11 schott glass, which is transparent to UV.
-UFC being a "scool" kit with interchangeable DF annuli, 20x and 40x phase contrast annulis and polarizer. It actually very... fun accesory, simple abbe condenser with quite a lot to offer.
-Alternatively you can use standard K51 with 4x-20x dry thanks to it's decentering capabilities.

I dont see much point in oil darkfield as you need to limit your lens aperture anyway, so for sake of convenience i've settled on 0,75 aperture and custom darkfield annuli in dic condenser. But, you got 2 lenses available, usually bundled with condenser:
-standard achromat 100x aperture limiter insert
-100x achromat with diaphragm

But if i were you, i would rather get something like Nikon Fluor 40/0.7-1.3


One other possibility to get more light, is to use / modify 50w UFL HBO dia illuminator that is much more common than 100W tungsten illuminator, and have much better FN coverage. I use to keep one of those modified for 100W halogen / flashlamp.
As Nikon and PZO illuminator systems are dramatically different, forget about any chance of adapting any of those to the other.

[Pau]

Phil, I have not so much experience as you, but I must say that my LED conversion for the Zeiss Standard and WL provides enough light for DF and cross pol at 100X (and DIC at 63x/1.4 as my 100s don't work with my DIC)

It is just a Cree XM-L2 (10W) mounted on an aluminium rod and placed at the very same position of the incandescent lamp filament in a Zeiss Lamphouse 60 with its original collimating optics. It fulfills the rear aperture for Köhler.
It's fed with a constant current driver at 2100mA (being 3000mA the maximum specification). The only issue I have is the big excess of light at low magnification even when dimmed at the minimum position of the pot, solved with strong ND filters at the illuminator base o subcondenser try.

I suppose that it also would work well with the Biolar.

My friend Francisco "fpelectronica" has done a more radical hack: he has his Biolar arm mounted in a much larger Nikon base

I also use the same approach for epifluorescence with "monochrome" LEDs with good results

http://www.cree.com/led-components/prod ... lamp-xm-l2

[phil m]

I have heard of this on those Zeiss models and it apparently works well for DF at 10 watts, although somewhere I recall a comment from one DIYer that 20 might be better at 100X. I assume that it has to do with the relatively short distance between the emitter and condenser on those models because 10 watts is not adequate on many physically larger microscopes. I suspect that if you tried the same set up on a Universal for instance, the illumination might not be adequate.
The Biolar is a pretty large based instrument and originally used 100 watt halogen for high resolution Df. I'm not sure a diy 10 watts through a long tube pathway, designed to collimate a 100watt filament is going to get there intact.

The other thing I continue to question about led illumination for microscopes is safety. I continue to use them sparingly. For incident illumination, I mix them with incandescent or halogen, mostly because I get better colour and contrast. Led light is very flat presumably due to it's monochtromaticity but there is a growing body of evidence from research, that high colour temperature monochromatic light is not very good for the eyes. Most of that comes from research into spatial lighting, so staring down at such through microscope eyepieces would seem to be a bit of a more severe risk, especially for children, since there is whole new generation of microscope enthusiasts brewing and much of the economical new hardware is led.

[Pau]

I have very little experience with the Biolar (I haven't one), athough it isn't much longer than the WL but the illumination train optics can be different.
I have not tested 100W on my Zeiss stands, but I used to get DF with a 50x/1.00 objective and both the 10W halogen and 15W older tungsten. The LED is much more powerful.
It happens that the XM-L LED size matches very well with the 100w halogen or 60W tungsten square filaments size. Some aftermarket solutions with larger COB LEDs like the RetroDiode are much less efficient and do need diffusers in the light path.

I also have concerns about the safety of intense blue emission of the white LEDs, specially after reading some papers of experiments in rats showing severe retina degradation after strong blue LEDs exposure.
Halogen also has its risks, as it emits some UV and also lots of blue when driven at high power/temperature.

[GaryB]

I use Cree XHP 35, 50 and 70 with upto 4,000 lumens! They are extremely bright and used in streetlights and car headlights. They make great hi-power halogen replacements.

[Ichthyophthirius]

I think I'm pretty handy with tools and I am capable of machining/welding/brazing and metal fabrication etc. I'm not sure even where to start (PZO wise).

Hi,

Could you show us which parts of the Biolar you already have available?
Do you have a simple lampholder to push into the base or do you have an external lamphouse?

If you have the simple lampholder as a template, converting to LED is easy. You need to machine an aluminium rod with the same external shape: http://www.mikroskopie-forum.de/index.p ... 5#msg94375

Then drill in some holes for the cables and add two threads for M2 screws holding an LED at the front http://www.photomacrography.net/forum/v ... 2&start=36

Good LED is the Cree XM-L2, as Pau suggested.

This is an option of the power supply https://www.ebay.com/itm/282885084920 The way you use this is to set a maximum current (e.g. 1000 mA) and then regulate the LED by changing the voltage (between 0 and 3.3 V). This for example would run your LED at 3 W maximum. All you have to do is add a little rotary knob to the "Adjust voltage" screw. Disclaimer: I didn't buy it from this seller. With unbranded electronics you never know but it looks the same as mine.

Regards, Ichty

[Smokedaddy]

For the stock PZO illuminator I'm using EiKO 8018 6v 15w blub. The LED illuminator Cree LED 5W - Color Temperature 6050 st.K (full spectrum white light) - with a Dimmer 30 - 100% and a 12V, AC adapter. I don't think the EiKO 8018 setup is bright enough for darkfield. The LED isn't either. I know absolutely nothing about LED other than flipping the switch to make them come on. I feel the LED isn't as bright as the blub.

As I've posted in another thread here (which probably should be combined with this one) I was able to get the super old Leitz working today but barely.

http://www.photomacrography.net/forum/v ... 902#229902

I haven't been able to do since since and I've tried for several hours. Looks like I was simply lucky. I have a TON of patience but I feel that I'm simply spinning my wheels.



-JW:

[Smokedaddy]

Anyway, I personally think the problem is there isn't enough light. I can't even see to focus on the diatom because it's so freaking dark. The image below was a 13 second exposure at ISO 800 (which I have never used on my 50D). Dunno if I have something setup incorrectly with the PZO or if there simply isn't enough light, or both. At least I know the Leitz Wetzlar condenser works and I didn't waste 50 bucks. This is using the stock PZO illuminator with a EiKO 8018 6v 15w blub max'ed out. Objective was just an old Leitz Wetzlar 40/0.75 Fluoreszenz. Diatom slide was oiled on the condenser. I think the LED is even less bright.



-JW:

[GaryB]

The Cree XHP35 will do a much better job. It's a 3.5mm emitter, 12V, 1A and will push 1800 lumens. It's available in standard die sizes so a direct swap out for what you have and simple to run from any 12v power source.

[Smokedaddy]

The Cree XHP35 will do a much better job. It's a 3.5mm emitter, 12V, 1A and will push 1800 lumens. It's available in standard die sizes so a direct swap out for what you have and simple to run from any 12v power source.

Like I said, I don't know squat about LED(s). Have a link to the specific one you're talking about. When I searched on eBay there were like 500 hits but all flashlights. Also are you saying that I de-solder the one I have in the aluminum holder and replace it ... or do they make them already assembled like a bulb and socket I'm holding in my hand?

[GaryB]

Here's where I bought mine
https://www.ledsupply.com/leds/cree-xla ... gh-density

Other color temps and die configurations are available elsewhere.
I search for 'xhp35 chip'
I think the one in your hand might be a 16mm die, the one linked is a standard star that I think is 20 or 22mm. They usually come ready to fit.