Why did a previous owner of this Nikon F100 etch these marks on the focusing screen?

[Trakl]

First, a public service announcement: Don't sell your cameras unless you're sure you won't miss them! I bought a EX condition Nikon F100 from KEH in 2013 for $189 and later sold it. I missed it, so I just bought another F100 from KEH . . . for almost twice as much! What a dope.

Anyway, this new (to me) F100 seems to work fine, but the focusing screen looks weird. Seems like someone etched hash marks up the sides, and little dots all around the frame. I don't understand what the thought process behind this might have been. Any ideas? Thanks for your thoughts!

 

[Nitroplait]

Reminds me a little of the Nikon F3 type T screen which was made to shoot within the old TV aspect ratio.
If you measure the aspect ratio of the dotted line, you may get a hint.

 

[Sirius Glass]

I own a F6 but it does not have those marks. The marks you are referring to look professionally made, perhaps it is factory made.

 

[AgX]

My first thought is to indicate a different aspect ratio. Maybe for making stills for inserting into a movie.
BUT to change the aspect ratio, only 2 sides need to be moved, not 4 ... And this does not explai the themore central added marks.

 

[MattKing]

If an F100 offers a 100% viewfinder, it may be useful to have indications where a slide mount or other mask may encroach on the image.

 

[AgX]

How is this done? One cannot "etch" a modern focusing screen. Maybe a inkjet-printed foil is added.

 

[AgX]

Matt, slide mounts are smaller by same distance at all four sides.

 

[Trakl]

Thanks so much for your replies. As best I can measure the aspect ratio of the added rectangle is about 7.75:11, which doesn't correspond to any standard ratio I know of.

I find the second vertical line of dots on the right side of the frame particularly mysterious, don't you?

The F100 has 96% viewfinder coverage, I believe.

Thanks again for your thoughts. I'm not too troubled by this "feature" of my new camera, but it does arouse my curiosity!

 

[madNbad]

It may be a screen from a D1 or D2 indicating the crop factor.

 

[AgX]

The marks you are referring to look professionally made, perhaps it is factory made.

There are at least two errors at the stripes.

 

[AgX]

It may be a screen from a D1 or D2 indicating the crop factor.

I am slow on the uptake. Could you explain more?

 

[Mike Lopez]

If an F100 offers a 100% viewfinder, it may be useful to have indications where a slide mount or other mask may encroach on the image.

Nikon saved the 100% coverage for its flagship models: the F, F2, etc.

 

[madNbad]

I am slow on the uptake. Could you explain more?

The first Nikon DSLR's, the D1 and D2 had APS-C sensors and a crop factor or 1.5. It could be a screen with marks showing where the full image would be for the digital cameras. Why it has the marks around the edges is a mystery to me.

 

[ic-racer]

You should be able to get a new screen without much fuss.

 

[abruzzi]

FYI, its almost certainly completely unrelated, but the ratio you measured on the internal box is pretty close to 1.4:1, which is the ratio for 5x7 sheet film.

 

[Roger Thoms]

If you don’t like the screen it should be pretty easy to find a replacement. I got the grid screen for my F100 a couple months ago. Lol, can’t remember whether I found it on EBay, KEH, Amazon or B&H.

Roger

Edit: It was B&H, $14.95, fits Nikon F100, Nikon D1.

 

[Lachlan Young]

I find the second vertical line of dots on the right side of the frame particularly mysterious, don't you?

Possibly to indicate cinema soundtrack - the inside-most set of dots seem academy-ratio compliant. That it's seemingly upside-down is a lot less confusing if you consider how it would be mounted on a copy stand (or rostrum camera etc for that matter). Does the inside of the back of the camera have any differences to any other F100's that you've seen?

 

[Sirius Glass]

It is impossible to understand some people's thinking and actions. Get the screen replaced with what you want instead.

 

[250swb]

The aspect ratio is exactly the same as A series paper sizes, so A4, A3 etc. The five dots on each edge may indicate border margins for images or text, or to align with printers registration marks, so my guess would be the camera has been used as a copy or layout camera in publishing or other associated media work.

 

[AgX]

You should be able to get a new screen without much fuss.

Yes, but I assume the idea of this thread is to trickle and feed our curiosity.
Which I appreciate very much.

 

[AgX]

The aspect ratio is exactly the same as A series paper sizes, so A4, A3 etc. The five dots on each edge may indicate border margins for images or text, or to align with printers registration marks, so my guess would be the camera has been used as a copy or layout camera in publishing or other associated media work.

Taking photos or doing copy work for printing was my second thought. And you gave a good explanation. But for copy work one needs no five AF points. And in any case of aspect-ratio indication, one does not need to alter all four sides.

 

[250swb]

Taking photos or doing copy work for printing was my second thought. And you gave a good explanation. But for copy work one needs no five AF points. And in any case of aspect-ratio indication, one does not need to alter all four sides.

What has AF got to do with it, maybe they didn't even have AF turned on? And if you were copying or doing layout all day seven days a week why wouldn't you want make the crop area central? Besides which the exact precise edge of the frame will change slightly depending on aperture (and also focal length) so scribing two lines to approximate A size paper up in one corner of the screen isn't going to be very accurate is it.

 

[AgX]

What has AF got to do with it, maybe they didn't even have AF turned on?

If one does not need AF, one does not need an AF screen.

 

[AgX]

And if you were copying or doing layout all day seven days a week why wouldn't you want make the crop area central?

Well, I would make the reduction frame as large as possible. Thus avoiding unnecessary rebates. (Though one can argue with such rebates being helpful as is done when speaking of non-SLR cameras.)

Besides which the exact precise edge of the frame will change slightly depending on aperture (and also focal length) so scribing two lines to approximate A size paper up in one corner of the screen isn't going to be very accurate is it.

I don't understand.

 

[250swb]

I don't understand.

I guess you never noticed how the spacing between film frames can change depending on what focal length lens you are using, most photographers have seen that at some time? But it does, and also with aperture. So aligning anything precisely using just one or more edges of the film gate on a camera that hasn't got a 100% viewfinder would be impossible.