nikon f3 with f4 focusing screen

hi!
today my second f3 body arrived from 'bay, an (non hp) addition version to my hp body.
when i took the finder off the new (non hp) camera, i discovered the B screen from an f4 instead of the original f3 screen inside (this was not mentioned in the auction). i also own an f4, so i know what an f4 screen looks like.
i conducted a series of highly unscientific tests with my micro nikkor 55 f/2.8 (i preset the 55 to minimal focusing distance and set the camera down on a newspaper to check and mark which word was in focus with the camera body aligned with the edge of the paper, the same with the other body and screen), and did my google homework before asking here (no real results, maybe i didnt look hard enough).
i found that there was no difference. objections? i just want to be sure i dont end up with all fuzzy pictures...
kevin

Hello,
the focussing screens of the F 3 and the F 4 have exactly the same size and form. They much brighter F 4 sreens can be used in the F 3, but this has never been officially confirmed by Nikon. Nikon had announced a series of brighter sreens for the F 3 but they never reached the market. You seem to be very accurate and by your tests you can be sure that the focus of your body/screen combination is o.k.

great! thanks!

No, sorry, this is all incorrect. Search harder. Perhaps on Photo.net. This was well known way back when. There IS a difference between F4 and F3 screens, they sit at different heights in the camera. This will lead to focussing errors. The updated F3 screens are "red dot", and have the same brite-screen technology as the F4 screens, so use those, and they actually did in fact 'make it to market'. Of course it is possible that the F3 you have was individually adjusted to that F4 screen, that is possible, test with a wide angle close up, but I can assure you, They Are Different. F and F2 screens are interchangable, and it is possible to use an F3 screen flipped around in an F2, but it was old news 10 years ago that F4 and F3 screens are not interchangable. Been a Nikon F3 shooter since the 80's and an F4 shooter since mid 90's and still have 4-5 bodies of each model and can fully assure you that they are different and will throw off the focus, you may not see it with all lenses at all distances but nonetheless the Error Exists.

The focus on film plane in F4 will be different than in your viewfinder if you use F3 screens in F4. Don't know the other way though, haven't bothered to check because I like the F3 screens more.

The actual focusing screen & condenser which are in 1 piece are equally sized though, only the frame seems to differ. So I've switched F4's focusing screen to a F3's focusing screen's frame and it works without problems.

Original F3 screens are traditional and pretty dim. "red dot" F3 screens still use the traditional technology, but are noticeably brighter. F4's focusing screens use some kind of new technology which results in even more brighter VF image.

Best way to notice the difference between traditional and new (laser cut?) screens are oof highlights.. they turn into rainbow-colored triangles/hexagons in new screens, while they look "normal", meaning no weird artifacts in traditional screens.

Of course when you increase the brightness of the screen you make compromises in other areas. Most noticeable is bokeh. Generally Nikon's focusing screens which I have tested don't give a very good idea about the bokeh the lens produces, or how thin the depth of field is.

- Bokeh looks usually a lot smoother than what it actually is. For example, Ai 35/1.4 which produces extremely busy bokeh looks perfectly smooth, like you had a 135/2 "cream machine" in your camera instead! I'd say the newer F4 type screens are an improvement in this regard, traditional screens blur oof areas completely in dreamy haze.
- When you increase brightness DoF gets exaggerated, meaning you think more of the image is in focuse than actually is.

"Most accurate" focusing screen I've seen is a piece of diffusion paper. With it bokeh looks in your VF as it will look on film, and dof is razor-thin. Problem is that the sample I had was probably at least 7 stops dimmer than proper screens Also the lack of fresnel produces extreme vignetting which reminded me of my 50's Rolleicord.

Yeah, switching out the frames would work. I've switched frames between F3 and F2 with no change. I've split and cleaned plenty of F3 and F4 screens and you could probably just swap out the plastic lower screen (leaving the original condenser). I'll have to check the sizes when I clean another one. A wild screen to look thru is the G series I think.

How the screen & conderser are held together? With some kind of glue? Do you need to apply new glue or something after splitting the focusing screen?

Never done it myself so I'm a bit curious

Ihmemies said:

How the screen & conderser are held together? ......

Click to expand...

I've split F and F2 screens, and the two parts are held together by a piece of clear tape around the perimeter.

Same way for F3 and F4 screens, you have to make sure that the thin lip of the screen sits correctly on the condenser, there is a tiny air space between. That sometimes collects fungus, and I have to split them to clean it. I've got some very thin clear mylar tape I got some odd place that seems to be the very exact replacement tape, if you are careful you can reuse it.

Is it possible for a focusing screen to display an even more unfocused image than the lens draws? I made a small, not very controlled test with 4 different focusing screens using a 85/1.4 lens:

http://hakkarainen.kuvat.fi/tempo/thedeathofviewfinder/

If I had a FF digital camera I could check how the actual image looked... anyways, the K screens look about the same while the diffuse paper looks completely different.

Edit: It would be interesting to compare C/D (presumably the same screen?), M & H screens too. I'm planning to get H1&H2 screens but I'm wondering would there be any point trying C/D or M screens? Do they show more or less DoF than K screens for example?