Howdy Dushan,
Thank you for the link to the Leitz Technical Information. This kind of literature is so difficult to get hold of.
This very topic, whether the Zeiss Jena "mf" microphotography attachment uses a relay optic, has just been the subject of another discussion
https://www.mikroskopie-forum.de/index.php?topic=19719.0 This is the evidence I found in the book Beyer (1973): Handbuch der Mikroskopie. The book is from the former Eastern Germany and presents the Zeiss Jena microscopes in great detail.
Figure 8.1 shows four options for changing a microscope set-up from visual (I) to microphotography (II-IV).
(III): When using a normal eyepiece ("Okular"), in order to project an image on film ("Bildebene") or in your case on a chip, you have to change the focus of the microscope, which results in a shortening of the optical tube length and therefore in spherical aberration. This is a problem with high numerical aperture dry objectives as described in the Leitz Technical Information Bulletin.
(II): To get around this problem, Leitz used a relay lens system as described in your link. In effect, this is a camera objective with an appropriate focal length ("Foto-Objektiv"). Leitz could therefore use regular, simple 10x Periplan eyepieces in their camera set-ups. This approach was also used by Zeiss West Germany.
(IV): The other option is to lift a regular eyepiece slightly off its normal position to enable it to project an image. The distance ("Δt
m") that it has to be lifted depends on the focal length of the eyepiece and the camera length. For a camera length ("k") of 125mm and a 10x eyepiece, the distance is 5mm.
(V): Zeiss Jena instead decided to develop dedicated microphotography projectives (MF) for this purpose. They project a real image at a distance of k=125mm while the focus position of the microscope remains unchanged. They do not require a relay lens. These MF projectives are used in the Zeiss Jena microphotography attachment "mf".
The attachment mf for small format film is pictured here.
As you can see in this drawing from the same book, the attachment mf for small format film on the left ("Zeiss-Aufsetzkamera mf") does not contain a relay optic, just a projective (2), and a beam splitter (5). The set-up for large format does contain a relay optic (11) but only because its camera length is longer than 125mm.
My interpretation of this book is that the MF projectives do not require a relay lens (you have an "MF-Projektiv K 8:1"?), although not all agree on this
https://www.mikroskopie-forum.de/index.php?topic=19719.0 However, I see an issue with the combination for the 8:1 projective and your camera with a relatively small micro 4/3 chip. The projective has a magnification equivalent to a 4x eyepiece. If you were to use it at the designated camera length of 125mm, you would only get a small crop of the total image.
There a two ways around this:
(1) You could bring the camera closer to the projective. I don't know if that has consequences for the focus position or the image quality. You might have to find out ourself. We tried to discuss this in the Forum as well, but so far we have no conclusion:
https://www.mikroskopie-forum.de/index.php?topic=18742.0(2) You use a camera objective or a microphotography attachment from another company as a relay lens. For example you could use a prime lens with your Olympus PEN E-PL1 and find a set-up that gives you a good crop. I don't know if that has consequences for the focus position or the image quality.
Regards,
Jon
Thema: Zeiss Jena Trinocular head for Nf Stand (Gelesen 19732 mal)