Tevidon 100mm modified to M42

[dickb]

Last year I bought some optical bits and pieces that turned out to include a Carl Zeiss Tevidon 100/2.8. Unfortunately it didn't have a mount or an adjustable aperture, instead it was fitted with a fixed stop of around f/11. Luckily it also included some other Tevidon barrels and I managed to transplant a working aperture (after much cursing of the flimsy aperture blades and my big fingers). Since I had seen examples on this forum of people having converted this lens to full frame use, I decided to convert the transplanted barrel to M42. Normally the C mount or bayonet mount limits the image circle to APS-C use or smaller. I reduced the length of the rear of the barrel a bit and now in close focus range, the vignetting is gone:

#1


#2


When focussed to infinity, there still is some vignetting, so I should try some more rigorous Dremel surgery for that, but for now, for close focus use I am quite pleased.

[kds315*]

It is a fine lens indeed and able to cover FF depending how adapted.

[spleenone]

Great try. Thumbs up. Would be interested in more samples from such glass.

[dickb]

The rear of the barrel is now as short as it can be. There is still some vignetting at infinity focus, possibly because of the m42 to Sony E adapter, or just from the lens design. Has anyone seen Tevidon 100/2.8 photos at infinity on full frame with less vignetting than this:




Anyway, I like using it like this:

[kds315*]

Here: https://www.flickr.com/search/?text=tevidon%20100mm

and especially here: https://www.flickr.com/photos/fh9449/albums/72157649086660471

[dickb]

Thanks Klaus. Interesting, I didn't know you could search on tags in Flickr. Curiously there is sometimes more than one lens listed in those tags. But unless everyone applied considerable vignetting reduction in post there should be a way of reducing the amount of vignetting seen in my setup currently. I'll try some other combinations of adapters.

[kds315*]

[dickb]

[kds315*]

[dickb]

OK, so my sarcasm detector may need some calibration. My portraits with this lens are just of the floral kind so far:





And for some context, the same phacelia portrayed by a MeOpta Meogon 80/2.8

2.8


5.6

[dickb]

And combined with some extension (in my case a modified Minolta Compact Bellows) it works nicely in the close focus / macro range: