View Full Version : An Aplanat question for Ole

Glenn Thoreson
28-Nov-2008, 20:00
I have a pretty little 4" f/6 Emil Busch Detectiv Aplanat No. 1-A. It's marked "R.O.J.A. vorm. Emil Busch, Rathenow". The lens is actually inscribed on the barrel "Busch's Detectiv Aplanat". The wording just seems stange to me, as if it were made for Busch by someone else (?). Ideas or thoughts on this one?

28-Nov-2008, 21:56
It's listed as a part of the standard Busch catalog in the Lens Vade Mecum.

There's a brief comment on the 10" Aplanat on the Whole Plate Column (http://groups.google.co.uk/group/wholeplate/web) along with other lenses:

http://groups.google.co.uk/group/wholeplate/web/3-50-brief-field-report-emil-busch-aplanat-10-f8-0-lens (http://groups.google.co.uk/group/wholeplate/web/3-50-brief-field-report-emil-busch-aplanat-10-f8-0-lens)

Standard Aplanats (Rapid Rectilinear type) had an aperture of f8.0; the Detective Aplanats were f6.0. I presume the wording reflects the wider aperture, or allusion to resolving more detail through a faster aperture.

From the Lens Vade Mecum: available in 4.7", 6.0", 7.5". Longer versions were slower ... covered 70 - 75 degrees. The 120mm (equiv.) covered 8x11cm at f6; 9x12cm at f12 and 12x15cm stopped down.

Kind regards,


Ole Tjugen
29-Nov-2008, 02:26
The Detektiv-Aplanat was made by Busch, who for a period traded under the name "R.O.J.A", an abbrebiation for "Rathenauer Optische Industrie Anstalt", I believe (J and I were represented by the same letter in German at the time, q.v. "ISCO" where "IS" is "Josef Schneider"). The dates for the use of ROJA in the VM seem suspicious to me, considering the relative rarity of Busch lenses without the ROJA name. :)

The Detektiv-Aplanat seems to be a continuation of the Portrait-Aplanat f:6, but quite likely with improved performance at large apertures.

Busch' Aplanats are in most cases stunningly good, with central resolution surpassing all but the very best (and modern) Anastigmats and quite adequate corner sharpness.

Glenn Thoreson
29-Nov-2008, 14:15
Thanks, all. This is a tiny little lens. It looks like the reflections are one strong, one tiny and rather weak, one strong. Identical on both cells, as would be expected. It's going on a 2X3 Speed Graphic to see how it does. I expect great things from this little gem on 6X7 format. :D

2-Dec-2008, 16:51
I also thank you Ole, My The Detektiv-Aplanat was made by Busch, 7 inch will be arrive-ing shortly here is the ad" “Busch’s Detectif Aplanat No. 3A Foc. 7 Ins. R.O.J.A. Vorm. Emil Busch Rathenow F-7 Will post something as soon as I can use it :

2-Dec-2008, 16:51
Glenn: I also thank you for pointing out this lens :

Glenn Thoreson
3-Dec-2008, 12:51
I traded very, and probably permanently, broken Contaflex IV to a fellow in New Zealand for this lens. I probably should be ashamed, but I'm not. :D

6-Dec-2008, 11:51
Glenn: When you said it was tiny you meant it: Just got my 7 inch focus 3-A detektiv-aplanat, this could get lost around here real quick [LOL] have fun : Lauren

Glenn Thoreson
6-Dec-2008, 18:31
Little, huh? My lens' barrel is about 3/4" in diameter and about 1" long in front of the flange.
Most of the room inthe barrel is taken up by the iris mechanism thingie. It cute. :D Let us know how your 7" specimen does.

7-Dec-2008, 00:23
About 1-3/8 w by 1-7/8 L Like I said this thing could get lost around here fast [LOL]