Allen, I don't understand your thinking in buying the Bessa R3A for use with a 35mm lens, but you seem to have thought it through very carefully. So, help me so that I might learn something.
You say that you want the increased magnification for use with a 50mm lens. I can see the benefit of the increased magnification with an ultra-fast 50 (f/1.5 or wider) but not with a standard 50 (f/2 or slower). Is the 50 you are contemplating very fast? Only here do i think that you'll see the benefits of the increased magnification - & with tele lenses, especially faster ones.
If you are planning to acquire an ultra-fast 50 & therefore the R3A, then I would consider using a 40 as your candid lens. I've found that it's a nice focal length for this purpose. Here I would echo Doug in that I think the parallax corrected framelines would outweigh any benefit from the slightly wider angle of view of the 35mm lens - not to mention the benefit of viewing & focusing through the same viewfinder.
I will also echo Doug in pointing out the depth of field issues with a fast or especially an ultra-fast lens. For portrait purposes this can be helpful, but for street shooting, I find myself more & more using smaller apertures to get the benefits of increased depth of field & therefore faster focusing. Of course, it has its benefits for low light shooting, but the DOF issues remain.
You asked about the whole viewfinder coverage. On his website, Stephen Gandy says that it is about 28mm on the R2. On another thread, one of our members calculated that it should be about 33mm on the R3A, but this is not from real life experience. You might try an e-mail to Stephen Gandy from his
www.cameraquest.com website to see if he has looked into this issue for the R3A yet.
In regard to the use of a 35 mm lens with 40mm framelines, consider this. Cosina reports that its framelines cover about 87% of the angle of view at any given focal length. This allows you to compose your picture for what will be shown in your photo after the edges are covered by a picture frame or if you have it developed with borders, etc. Use of the 35mm framelines with a 40mm lens means that the framelines are showing you almost exactly what the lens sees because 87% of 35mm is roughly 40mm. However, when doing the opposite, i.e. 35 mm lens with 40mm framelines, the framelines will only cover about 75% of the 35mm angle of view. This is because the 40mm framelines are only covering 87% of the 40mm angle of view to begin with. When you then want to use these framelines with the even wider 35mm angle of view . . . Well, you get the picture. I'm sure that with some practice, it can be mastered - especially if the whole viewfinder coverage approximates 35mm. As Doug suggests, however, it may be awkward to see the entire viewfinder area of coverage.
Finally, welcome to the Forum!
🙂 I'm sure that I will learn from your posts.
