bosjohn
Member
I have used many screw mount Leicas and I am too old to start calling the thread mounts. I, and I suspect most of you, when I first get the camera I look at something about fifteen feet away and focus the range finder using the focusing lever thinking this is a dioptor correction device. The I forget about it.
I came across an interesting statement in my Leica Pocket guide third edition by Kisselbach from 1952 in which he refers to this lever and says its purpose is to focus the range finder on near and far subjects. It never occurred to me before to change the focus of the rangefinder because once set for my eyesight why should i change it? so I tried re focusing when working at three or four feet from a subject. What an Eureka moment wow I mean if you have not tried this i recommend you do because its make a very noticeable difference in focusing on close subjects.
I got into a rather lengthy discussion about this lever over in dpreview as it is my position that the lever was meant to do exactly that, focus the one and a half power telescope which was introduce in the three a.
Every one over in dpreview insisted its a diopter correction device and in fact both My Dennis Laney and Jim Lager refer to it as such. Could I have mis interpreted this statement then in the Pocket Leica Book?
I have looked at several other post war leica use guides and they all called it a diopter correction lever.
So I went back to my Leica F instruction manual. Now its really gets interesting as in this manual the official Leica manual that comes with the camera Leitz now refers to the lever as a device to focus on near and far subjects and to correct for eye sight and gives a range of diopters.
I then went back to the D in which it says essentially the same thing both.
Finally I referred to the Leica 3 and 3a instruction manual and here it says
"The eye piece is adjustable by turning the milled mount,so that everyone can focus near or distant objects to the greatest possible sharpness. Swung up its used for distances up to 3 1/4 ft and swung down for infinity and set midway, for distances from about 4 feet to 15 feet." there is no mention of diopter correction.
this is of course an english translation or written in english. I hope some of you will let me know if the German manual differs.
It seems then to me that when the lever was first introduced Leitz was not thinking about eyesight correction but very shortly there after the idea was included in the instructions and now days everyone calls it a diopter correction lever and so very few of us bother to refocus when working in close or medium distances.
I believe the range finder magnification and the accompanying lever was done in order to accommodate the accuracy needed to focus the new f2 Summar that was introduced at about the same time.
So if any of you screw mount users have not tried refocusing your range finder when working close try it.
Most interesting to me is why Leitz changed how they describe the lever.
if anyone has some insight into why the change I would be very interested in knowing it.
I came across an interesting statement in my Leica Pocket guide third edition by Kisselbach from 1952 in which he refers to this lever and says its purpose is to focus the range finder on near and far subjects. It never occurred to me before to change the focus of the rangefinder because once set for my eyesight why should i change it? so I tried re focusing when working at three or four feet from a subject. What an Eureka moment wow I mean if you have not tried this i recommend you do because its make a very noticeable difference in focusing on close subjects.
I got into a rather lengthy discussion about this lever over in dpreview as it is my position that the lever was meant to do exactly that, focus the one and a half power telescope which was introduce in the three a.
Every one over in dpreview insisted its a diopter correction device and in fact both My Dennis Laney and Jim Lager refer to it as such. Could I have mis interpreted this statement then in the Pocket Leica Book?
I have looked at several other post war leica use guides and they all called it a diopter correction lever.
So I went back to my Leica F instruction manual. Now its really gets interesting as in this manual the official Leica manual that comes with the camera Leitz now refers to the lever as a device to focus on near and far subjects and to correct for eye sight and gives a range of diopters.
I then went back to the D in which it says essentially the same thing both.
Finally I referred to the Leica 3 and 3a instruction manual and here it says
"The eye piece is adjustable by turning the milled mount,so that everyone can focus near or distant objects to the greatest possible sharpness. Swung up its used for distances up to 3 1/4 ft and swung down for infinity and set midway, for distances from about 4 feet to 15 feet." there is no mention of diopter correction.
this is of course an english translation or written in english. I hope some of you will let me know if the German manual differs.
It seems then to me that when the lever was first introduced Leitz was not thinking about eyesight correction but very shortly there after the idea was included in the instructions and now days everyone calls it a diopter correction lever and so very few of us bother to refocus when working in close or medium distances.
I believe the range finder magnification and the accompanying lever was done in order to accommodate the accuracy needed to focus the new f2 Summar that was introduced at about the same time.
So if any of you screw mount users have not tried refocusing your range finder when working close try it.
Most interesting to me is why Leitz changed how they describe the lever.
if anyone has some insight into why the change I would be very interested in knowing it.
