Trinocular head for PZO dic ?

[zzffnn]

Hi,

The tube length of the Olympus head is 7 mm longer (120 mm) than that of the PZO Biolar (113 mm). It's OK for low NA objectives but for high NA it's a bit too much. You'd have to see if the Olympus eyepiece tubes can be adjusted by those 7 mm.

Regards, Ichty

Wow, Ichty, you got it again! How did you manage to measure so precisely, or did you compare official specification?

[Ichthyophthirius]

Hi Fan,

Both are 160 mm tube length microscopes. Both the Olympus CH and the PZO Biolar have no relay lenses in the nosepieces or the body (just air).

So I measured the distance between the bottom of the nosepiece to the top of the dovetail mount (i.e. nosepiece + body) as well as I could. As far as I can tell, it's 40 mm in Olympus and 47 mm in PZO. The remainder of the 160 mm must be in the trinocular head!

Regards, Ichty

[JohnyM]

It changes a lot, as hight NA lenses are pretty "wideangle" so "bellows factor" is huge.

[Ichthyophthirius]

Hi,

I dug out my CH2 trinocular head and had a look how much adjustment it allows.

The Olympus CH2 head has adjustable eyepiece tubes although these are not diopters. There is a scale from 53-72 (picture 1) that corresponds to the scales on the eyepiece tubes 53-72 (picture 2; actal range on the tubes off the scale is approx 52-75).

These scales are used to adjust the tube length to the distance of the eyes of the user. The head can accommodate users with eye distances between 53 and 72 mm by sliding the eyepiece tubes horizontally. This changes the tube length of the microscope away from 160 mm. To adjust this change, the scales on the eyepiece tubes have to be set to the reading on the horizontal scale.

Now, according to my measurements, the eyepiece tubes have a range of 11.8 mm (picture 3). This gives you more than the 7 mm downward adjustment needed, as long as your eye distance is 52 mm. The further your eyes are apart, the smaller the scope for downward adjustment.

This is what I measured:

Eye distance [mm] Downward range [mm]
52 .... 11.8
60 .... 7.0
65 .... 5.0
75 .... 0

So as long as your eye distance is not too wide, you have enough range to adjust the tube length down by 7 mm; 5 mm would still be sufficient!

If in addition you use microscope eyepieces with diopter adjustment, you might be able to shorten your tube length further!

I would say if the Olympus dovetail fits the PZO mount (I have't tried this), it looks like a good option.

Regards, Ichty

[zzffnn]

Thank you for sharing, Ichty. Your measurements and reasoning is very convincing and helpful.

[Ichthyophthirius]

Before I forget: of course the photoport is not adjustable! So the tube at the photoport would have to be exchanged for a custom-made one, 7 mm or so shorter than the original.

[Smokedaddy]

I appreciate all of the help and suggestions so far. I should mention too that the PZO hasn't even arrived yet. Who knows what sort of shipping damage may occur. I even offered the seller more money to package everything a specific way He said he had 17 years of experience shipping things like the PZO and not to worry. I know a couple of people that have purchased from him in the past and experienced no problems.

I feel that I am able to fabricate/machine just about anything (within reason) related to this conversation. The main problem I have is I am a complete novice in the microscope community. That includes most of the nomenclature and technical aspects discussed on the forums. Naturally I am more than willing to learn, as slow as it may be for me.

I opted for the PZO DIC for cost reasons and because finding all the necessary DIC components (like the intermediate adapter) for my Optiphot seemed nearly impossible, similar to finding a Biolara MNT6 head for the PZO Biolar. I also didn't want to purchase a complete new Nikon DIC scope. So I took my changes on the PZO DIC. Maybe it was the wrong option. Either way no worries on my end.

I am also interested in photographing diatoms using DIC and the overall reason for the purchase of the PZO DIC. I didn't want to do afocal imaging either but if that is the only option I have then there isn't much I can do about it. IF a Frankenstein type trinocular setup is necessary and can be done using a Olympus BH-2 or some other brand, that's fine with me.

ALSO if I can eliminate the trinocular head completely (as in my setup below) and some how adapted my Canon 50D to the PZO that would be great too. I have no idea what may be inside the MPI5 or if corrective optics are inside it or in the PZO binocular head? So I am stuck knowing exactly what direction to go and the proper questions to ask.

I know my Optiphot setup requires these measurements.



Regards,
-JW: