Nikon + Zeiss PMII, live view and other ?s

[telemetrist]

Hi,

I've ordered a 2.0x coupler and a T-mount for nikon cameras and am currently using a D3000 to do petrography work with two Zeiss Photomicroscope IIs. This setup WORKS but I want more as this lacks live view and adjusting ones self above the camera to setup the photo is tedious.

I need to replace the D3000 for another Nikon that will let me have live view on a monitor, either through a data cable (usb/firewire) or an analog cable. I see that nikon makes software called Camera Control Pro 2 that seems to do what I would want assuming I buy a DE5100/D7000/higher end camera body.

Suggestions on what to buy camera wise (i'm not tied to Nikon, perhaps Canon offers better software for live view)?

Another question i have that might not be feasible, one microscope is setup for transmitted light the other for reflected. Ideally I'd like to have two Nikons with live view and be able to overlay the images onto each other. Has anyone done anything like this?

Thank you

[Pau]

Suggestions on what to buy camera wise (i'm not tied to Nikon, perhaps Canon offers better software for live view)?

Another question i have that might not be feasible, one microscope is setup for transmitted light the other for reflected. Ideally I'd like to have two Nikons with live view and be able to overlay the images onto each other. Has anyone done anything like this?

Well, Canon has two advantages for microscope use: the tethering software is free, with the CD in the camera box, and in all recent models but 1D series and 60D the exposure in Live View beguins without any movement (we call it EFSC, electronic first shutter courtain) and it is vibration free, a great feature when shotting at high magnification with continuos illumination.

About your last question, the best approach, if possible would, be to combine both illumination modes in one microscope and just switch the light source between shots. If both are Zeiss PM it must be physically doable.

[telemetrist]

thanks for the help, looks like we're going canon!

could I run two instances of their tethering software at once connected to two different cameras on two different scopes?

[telemetrist]

While the Zeiss AxioCams are considerably more expensive than most dSLRs... what's the advantage to using one? I've been looking into this and it seems their biggest advantage is providing truer color reproduction and higher dynamic range as they shift the CCD to capture the RGB values mean the image has little in the way of interpolation. In the case of the AxioCam HRc this looks as it might take some time as it has to take ~27 exposures to produce their high resolution color image. Maybe I'm wrong but it seems as if the 7d for $1200 is a better choice than a $12,000 Axiocam (Or even their lower resolution/$6000)

[telemetrist]

How much shake is introduced by the shutter actuation? I seem unable to obtain any sharp images. This is with transmitted light. The edges have some distortion too which I assume is due to my 2.0x camera adapter.

[Pau]

I find two issues in the posted picture:

1. general unsharpness. I may be due to camera vibration or to focusing problems (or both). To test if it is due to camera vibration you can try the following trick:
- Set the ligth and ISO to obtain an expossure of about 1 second
- Set the camera to M mode and adjust 2s exposure
- Darken the room
- Beguin the exposure with the microscope light source covered. After 1s uncover the light source without touching the scope and let the exposure ends (of course be sure that there aren't any other sources of environemental vibration)
Usually you can deal with this issue just using exposures over 1s.

2. Chromatic aberration and more unsharpness towards the periphery of the image. This is an optical issue.
- You need to use Plan objectives. Which ones do you use?
- Zeiss objectives of this era do need complementary aberration corrections at the eyepiece, so you need to use a KPL eyepiece in the optical path to have a fully corrected image and a lens over it to form the image at the camera sensor, some kind of "afocal" setup.
I don't know what kind of adapter and setup do you use to couple the camera. You can post images of your setup and info about if the adapter uses its own optics and or not the eyepiece (I think you're using one of the cheap modern ones that have ist own optics and slide in microscope tube. Those do not correct aberrations. Am I right?)

About afocal adaptation to a Zeiss microscope I posted some info at:

http://www.photomacrography.net/forum/v ... ope+setups

[telemetrist]

Thank you for the info, I will be trying that method to see about vibration or focusing issues. I believe we have Plan objectives. The adapter we're using (pictured) was not cheap and I do not believe it corrects aberrations. I'm just getting up to speed about these. I'm about to tear one of these scopes apart and clean it as they've been sitting around for 10+ years and have accumulated some dust. I have yet to try anything with the immersion objective. Thanks again your help and patience.

[Pau]

Yes, the adapter isn't cheap
http://webstore.diaginc.com/DD20NLT-2-0 ... d20nlt.htm

- It doesn't seem adequate for objectives that need complementary correction like Zeiss, the compatible instrument list is mainly composed by intruments that do not need complementary correction or do it at the tube lens, with the notable exception of the Leitz ones and may be the Wild (?).

- About the objectives, BTW the marked Epiplan and Plan are plan corrected, the other ones likely no.
The Epiplan with NA 0.40 or higher aren't adequate for glass covered slides.

- In my experience, standard petrographic thin sections doesn't work very well with high magnification objectives

[telemetrist]

Well as you see I already have the adapter.

Can I do correction? Thank you for the info about the Epiplan NA > 0.40 objectives. So basically we'll be limited to using lower power objectives to do the petrography? This really won't be a problem though it'd be nice when doing counts though that brings me to my next question.

Can I obtain sharp images from this microscope? Should I purchase a modern microscope for my application?

[Pau]

Can I do correction? Thank you for the info about the Epiplan NA > 0.40 objectives. So basically we'll be limited to using lower power objectives to do the petrography? This really won't be a problem though it'd be nice when doing counts though that brings me to my next question.

To make the adequate correction you need a Zeiss KPL eyepiece and a lens over it as I linked.
Shotting RAW you can correct de chromatic aberration in software, but the periphery still may look less sharp tan desirable
You can use higher mag. objectives, but in my experience the image is more problematic tha with low power ones. In any case in the very basic petrography I do I most need to see the textural characteristics of the rock more than details of very small minerals...

Can I obtain sharp images from this microscope? Should I purchase a modern microscope for my application?

Of course you can!. Those are PHOTOmicroscopes.
I work with a Standard, a cheaper model fom the same era.

Here you have a sample of one of my typical petro shots:


Take a look at the work of a fellow forum member with a similar scope:
http://www.microscopeitaly.it/

[telemetrist]

To make the adequate correction you need a Zeiss KPL eyepiece and a lens over it as I linked.

This is exactly it. I was able to use a zeiss phototube I had sitting around and couple it with the coupler to produce megascope. However, the coupler has a 2.0x magnification which I think is causing severe focusing and sharpness issues but it's all I have until a new adapter arrives. Will keep you updated.

Can I use new objectives on this old microscope?

[Pau]

Yes, with the phototube pictured on the table you can make an excellent afocal setup, for exemple with a KPL 10X and a 40mm camera lens (Canon has just released a 40mm pancake that seem ideal for this work)

Can I use new objectives on this old microscope?

Yes and no: You need DIN objectives (RMS mount, 45mm parfocal distance, corrected for tube lengh 160mm).
All major brands have discontinued DIN objectives in favor of infinite corrected ones, and all new ones I know are from Chinese and Indian makers. I don't think they will be better than the classic Zeiss you have.

But you may use better old objectives: Fluorites, Plan Fluorites and Pan Apo from Zeiss (adequate with your KPL eyepieces), Leitz (best used with Leitz Periplan eyepieces) Olympus (again better paired with its eyepieces) and Nikon CF (this ones don't need correction and would work likely OK with your photoadapter.

[telemetrist]

Any idea where the best place to find a 10x KPL eyepiece? I'm currently using the 12.5x and it's OK but I think the 10x is going to be on the money. I've tried an 8x and it's not enough. New 7d is more or less attached to the zeiss tube and the pictures are getting much sharper when using live view for focusing!

[Pau]

Yes, much better!

Any idea where the best place to find a 10x KPL eyepiece? I'm currently using the 12.5x and it's OK but I think the 10x is going to be on the money. I've tried an 8x and it's not enough. New 7d is more or less attached to the zeiss tube and the pictures are getting much sharper when using live view for focusing!

I don't understand well your setup, are you placing the 2X adapter over the KPL eyepiece mounted in the original Zeiss phototube?. For a APSc camera the total relay magnification to match well the image of the eyepieces is about 1.6X. I most use a 6.3X eyepiece and a Zeiss 0.25X photo adapter (63mm FL) over it. If you have a 50mm lens the KPL 8X will be perfect. (you need high eyepoint eyepieces, usually marked with eyeglasses symbol, like your viewing ones)

How much cropped is the image on the camera in comparison with the the one you view through the eyepieces?

About a source of eyepieces, I see them very often at eBay.