Would I need an external viewfinder for the ZM 25mm Biogon?

geoabbott

Member
Local time
4:07 PM
Joined
Oct 25, 2006
Messages
24
This lens is appealing to me for its effective 37.5 mm focal length on the R-D1 and would be even more desirable if it didn't need an external viewfinder. Any thoughts on whether the 28mm setting alone would possibly work with this lens? From what I gather, the lens is also not rf coupled so that appears to be an additional problem as well when shooting at wide aperture. Thanks for the feedback.

George
 
I'm pretty sure that the ZI 25mm lens is rangefinder coupled.

You may be thinking of the CV 25mm which is not coupled.

No first hand VF experience but my guess is that the framing with the internal VF only will be pretty tight. I think that the 28mm frame lines with a 28mm lens is marginal.
 
I've used my CV 25/4 on my R-D1 using the 28mm framelines. It's not optimal. It can be done but you miss out a lot of information on all sides. That might not be too critical if you keep the subject central in the frame but once you want information on the sides to play a part in the shot, the 28mm framelines are of little help in critically composing a shot with the CV 25. Just my experience, of course. :)
 
If you don't use glasses, you may be able to do it the way I used to shoot with a 35 on my Leica M3: use the whole viewfinder as "framelines". I never used a 25 in the RD-1s but the whole finder shows slightly less FOV than my 21 Biogon, so it should do the trick for a 25.

With glasses on, I think it won't work, not enough eye-relief to see the whole VF... :-(

Anyway, I got used to an external viewfinder. I bought the 28/35 minifinder for the M3 (lovely!) and sometimes even use it on the RD-1s with the 21 (coverage is between both frames). I've already ordered another in black to keep on the RD-1s, because the 21D finder is bulkier and tends to slip off easily. The image quality, though, is better than the 28/35 minifinder, of course.
 
Thanks, jvr. How do you like the Zeiss ZM 21/2.8 Biogon with the R-D1? I'm trying to decide between the ZM 21 and ZM 25.
 
geoabbott, the 21/2.8 is a great lens, optically and mechanically. The only nuisances are:

1) You really need an external VF (I guess you could get away without one with the 25) to even stand a chance to frame correctly. This is particularly annoying when using a flash: not hotshoe availbale... I find myself using my 28 Ultron with flash more than I would like, just because I don't need an external VF.

2) It's a bit longer (size) than I would like to be. I was used to hang around with my M3 + Summaron 35/3.5 and I was expecting the 21/2.8 to serve the same purpose. It's not nearly as pocketable...

The 25 could help you on both counts: in an emergency I guess I could use the whole VF as a "guesstimate" and the 25 is shorter.

My reasoning was: I already have a 28 (and the 25 is not different enough from the 28) and I like wide-angles (I'm having a lot of fun with the 12/5.6 on my M3!! :), so the 21 is the wiser choice.

If I didn't have a 28, maybe the 25 was a good option.

Optically, I only read good thinks about the 25: it's the same formula as the 21, 25 is an easier focal, could only be better than the 21. And believe me: the 21 delivers :)
 
I've used the ZM 25 on the RD1 for almost a year with no external viewfinder.

For shot composition I place the edges of the main subject at the extremes of the viewfinder, for example, if shooting a car I move so that the bumpers are just inside the finder. The shot will include the bumpers plus about a metre of surrounding landscape.

Working this way means I must move back from the finder a few centimetres till my eye can take in the edges properly, it's anoying.

The image quality of the 25 is right up there (also use Crons: 35 f2 asph, and 50 f2). Coupled focus is spot-on.

Shots from the 25 on the R1 often need exposure compensation down two stops from the correct meter reading, and then many shots need fine tuning down a little further.
 
geoabbott said:
From what I gather, the lens is also not rf coupled so that appears to be an additional problem as well when shooting at wide aperture. Thanks for the feedback.

George

The ZM 25/2.8 Biogon is rangefinder coupled down to a distance of 0.7 meters (27.5 inches). However, it can be focused to a minimum focus distance of 0.5 meters (19.7 inches). To get there, it decouples below 0.7 m & must be scale focused for distances below that.
 
Last edited:
Back
Top Bottom