Bronica and split screen focusing

Sony 24-70mm F4 Vario-Tessar T* FE OSS

01/21/2006 12:23:51 PM · #1

Ok, well that was fun.

My downstairs roommate (whom I have quoted and referred to in the past on these forums) is doing a lot less with his photo equipment lately and has been putting some of his things up for sale.

He sold me his 'magic drainpipe'. Whee!

He invited me downstairs this evening to show me his Bronica Medium Format 6x6 camera that he's selling for a STEAL.

It has 6 lenses 40mm-150mm (all protected by filters and in A+ condition), a proper extension tube (one of his lenses is a macro too), a high end light meter (minolta), as well was 1 or 2 extra viewfinders (including one that has an auto exposure guide), an extra film back, a polaroid back and uhhhh... I think that's it.

Now I know a lot of people think these are a little antiquidated, but holy crap this is a neat camera. The poor guy is trying to sell the whole bundle, and his first offer was $2000 US for the whole thing. I don't think he's considering that offer too seriously.

It was the first time I have ever used anything like it.

He was patient and showed me a lot of things about cameras and how to work the things.

He talked about how looking at things in a different way could really help a person to focus on different parts of photography.

I was enthralled by the way it looked by using the waist-shooting style and just looking down at the ground glass. Wow. Turning everything into 2D and just watching it unfold is almost like watching reality as a dream in moving photographs.

One thing that he showed me how to use that I had never encountered before (with understanding) was the split screen focusing. Wow!

I have always had poor eyesight, from youth on and that has always been a major obstacle in my mind towards getting involved with photography. I felt that I could never really trust my eyes to get something properly focused. I have since had laser surgery on my eyes, so I am no longer restricted to contacts or glasses, but I still feel a little uncomfortable with manual focus.

With the split screen focusing, this issue faded away as if it were nothing at all.

What an incredibly powerful tool this is.

My question therefore is about this remarkable tool:

How does it work? (I know how to use it now)

Are there any digital cameras that use it?

What would be involved in implementing something like this in a camera.

You know, give me whatever you feel like that is encyclopedic and technical. I drink this kind of stuff like uhhh, whatever is suitable to drink great quantities of quickly... strawberry milkshakes?

Thanks!

Edit: typo

Message edited by author 2006-01-21 12:24:34.

Bear_Music

Samsung Galaxy S24 Ultra

01/21/2006 12:34:05 PM · #2

Split-screen focusing is highly problematical a lot of the time. All the old film dSLRs had it, or at least would accept screens that used it, but it needs a lot of light to work well. Personally, I hated it and swapped out to plain, matte-glass screens with grids on them.

Some dSLRs have this feature as an option, those models that have interchangeable screens. Katz Eye Optics makes a split-prism focusing screen for the 20D but you have to dismantle the camera a bit to install it. It costs about $100.

R.

Edit to add; they have them for MANY dSLR models, including Canon's 10D, 20D, 300D, and 350xt and Nikon's d70 and D70s.

//www.katzeyeoptics.com/page--Custom-Focusing-Screens--store.html

Message edited by author 2006-01-21 12:38:00.

Sony 24-70mm F4 Vario-Tessar T* FE OSS

01/21/2006 09:57:02 PM · #3

That's great to know. I'd love to see some really close-up diagrams or photos to understand how it works better.

Would changing the prism be difficult?

Would it void the warranty?

Would it affect the autofocus?

I don't think I would change it because autofocus tends to work very well too, but it's an interesting idea.

Bear_Music

Samsung Galaxy S24 Ultra

01/21/2006 10:03:25 PM · #4

Originally posted by eschelar:

The focusing screen has no effect whatsoever on the autofocus; that happens in a different part of the camera.

R.

David.C

Nikon AF Nikkor 50mm f/1.8D

01/21/2006 10:23:27 PM · #5

I bought my D70 used, and it came with a screen with 8x10 crop marks added. I was hesitant at first, but then decided that if the guy hadn't told me they were added I would likely never have known and been happy with it -- so now I'm happy with it with them. :D

Anyway, BrightScreen is the company that added the crop marks and they have a number of other screen options available -- including split-focus. Being new to this level of things I didn't even know the focusing screen was replacable -- but apparently this company has been providing custom focus screens for a couple of decades now.

I have used a camera with a split-focus screen once -- but my sister (whom I borrowed it from) didn't tell me how to use it, so I muffed the focus on nearly all shots. :(

David

hyperfocal

Nikon D7000

Nikon MF 105mm f/2.5 AIS

01/22/2006 12:35:51 PM · #6

I've owned both ETR (645) & SQ (6x6) systems and think they are/were very underrated cameras. All the "P" lenses have modern coatings and great glass. The older lenses are no dogs either except for the earliest ETR lenses that were not coated (fine for B&W not so good for color).

If you do get the camera I would suggest getting the 35mm wide back. It allows you to shoot panoramic images on 35mm film (24x54mm). This of course would require replacing the above mentioned focusing screen. I personally like the all-matt screen on a format as large as this.

Canon EF 35-80mm f/4.0-5.6 III

01/22/2006 12:39:18 PM · #7

From what I gather, it's almost more of a curiosity at this point for those who shoot manual lenses. It seems that it is very, very useful for architectural stuff, as anything that moves is very hard to really lock down with exactness. I also was kind of surprised about the way that part of it darkens some of the time.

My friend keeps recommending to me to look around for a cheap vintage camera, so I can have the experience of using it. I heard that now and again, you can find really fun little Rollei's.

I was admittedly blown away by what it's like to shoot with a nice big ground glass focusing screen, looking down. It was genuinely bizarre.

Thanks for your comments about the screens. I will have a look!

I don't actually think that I would get it done, especially considering the added issue of shipping, but it's interesting to read about.

I'd love to find a link about the theory of how it works.

robjamez

Canon EOS-350D Rebel XT

01/22/2006 03:22:07 PM · #8

//doug.kerr.home.att.net/pumpkin/Split_Prism.pdf