Topic: Pentacon AV 2.8/80 - the poor man's Trioplan ;)

I found this slide projector lens while cleaning my parent's flooded cellar and decided to do something with it smile

It is a simple triplet design, just like the Trioplan 2.8/50 & 2.8/100, it was even manufactured by Meyer Optik in Görlitz, which was, after joining with various other factories, renamed Pentacon by the early 70's. There is a longer version - Diaplan / Pentacon AV 2.8/100 - which is in fact the Trioplan's optics without an aperture mechanism in a plastic housing. My 2.8/80 is built in exactly the same way, very lightweight (<100g).

http://farm9.staticflickr.com/8264/8778019043_2cb7fa72ba_z.jpg
lens focussed to 1.5m

http://farm6.staticflickr.com/5348/8778019589_91e1f60061_z.jpg
lens focussed to 0.3m

I adapted it using a plain M42-NEX adapter and some duct tape - it looks an awful lot like a remnant of a failed Mythbuster's project wink - but is in fact pretty sturdy. In this setup, it focusses between 0,3cm and 1,5m, which is nice for some dreamy flower-closeups or head portraits. I suppose, using a thinner adapter (LTM-NEX) could provide infinity focus.
Imagequality wise - it is okayish, pretty sharp in the image centre, some heavy halo or glow on sharp bits bits due to spherical abberation and - most important - the Trioplan's highlight discs with an accentuated outer rim.

http://farm9.staticflickr.com/8413/8778016935_42b0a7149d_c.jpg
some camera porn wink
larger: http://farm9.staticflickr.com/8413/8778 … 397e_o.jpg

Re: Pentacon AV 2.8/80 - the poor man's Trioplan ;)

Nice idea , Barney and more than decent picture !
I have to try it ....

I am a Pentacon and kiev( MF and35 mm) user,and also :contaxII,III,IIa  ,contaflex , contarex bullseye ,voigtlander ....