Rollei prism problem...

[PatrickT]

I picked up a Rolleiflex prism today as I've been wanting to try one for a while now.

When looking through the prism on the Rollei, I can't seem to get anything in focus. It looks as though the diopter setting was changed or something, but I can't seem to find a marking on the screw-in eyepiece.

Is it possible that it is a diopter problem? Did these prisms come with different diopter settings? Or should I be worried about something else...?

Thanks!

 

[Steve Roberts]

Patrick,
Having tried a prism myself, I wouldn't be without it. Life is so much easier when left is left and right is right. There's a small sacrifice in brightness, but IMHO it's minimal and not a problem.
I once had focussing problems with my Rolleiflex, took the viewing screen off and found that the mirror underneath had become unseated. I don't remember the details, but it was fairly obvious where it should have been. Might be worth looking at, as perhaps a focussing error is exacerbated by the prism? Just a thought.

Steve

 

[TimVermont]

Patrick, are you referring to a prism for the TLRs, or to one of the prisms for the 6000 series, or the SL66s? If either of the latter two camera families, which prism?

 

[Richard S. (rich815)]

What Tim said, which us it? Sounds to me like it's not seated properly or the focusing screen became unseated or shifted.

 

[PatrickT]

Sorry guys, I'm talking about the TLR prism. The camera itself is fine, and focusing is a breeze without the prism, so I doubt that it had anything to do with the camera.

As far as I can tell, the prism is seated properly. To me it seems as if either something us screwed up internally (in the prism) or I unknowingly have an eyepiece with a different diopter setting.

If it is the eyepiece, can you get these anywhere? Seems like that should be the first thing I try.

 

[Steve Roberts]

I'm not at home to look, but I don't remember a screw in optical eyepiece, only a rubber eye cup.
Have you tried just taking out the eyepiece?
Steve

 

[PatrickT]

The whole eyepiece unscrews. I have tried taking it out and it just leaves a hole in the prism.

 

[andys93integra]

The TLR prism had different diopters you can attach ranging (-3,-2,-1,0,+1+2+3). Not sure where one would find them though, might have to search hard. I use the prism on both my Rolleis' mainly because i don't have waist level finders. Not sure which diopter i have as there are no markings on it.

 

[PatrickT]

Thanks. Mine does bit have a marking either. I'll start looking around...

 

[dpurdy]

Diopters with no mark are stock normal.. the pluses and minuses are clearly marked on the outside of the eye piece. I have both the new version and the old version. They are different in that the newer one comes in two pieces... the diopter is a lens that screws into the holder whereas the older one is all one piece. When you take the eye piece out you should see in the hole a triangular piece of glass sort of like and upside down superman shield. It should not be just a hole. I can't think what else might be wrong with your prism. When you screw out the eyepiece it does have a lens in it?
You might write these guys: www.dhw-fototechnik.de/ I know they are still selling the new cameras and I have bought a diopter from them.
Where are you? Any chance you are in the US pacific NW?
Dennis

 

[PatrickT]

Hi Dennis, thanks for the reply. You're right, it isn't just a hole...there is an upside down mirror thing in there.

My eyepiece doesn't have a marking, but I'm afraid it could have been rubbed off. I'll have to see if the diopter lens can unscrew.

Nope, not in the pnw. I'll see if I can contact those guys.

Thanks!

 

[dpurdy]

Your problem still doesn't make sense to me. If you take the prism off you can focus the focusing screen normally? There is a big piece of rounded glass on the bottom of the prism?
If you take the prism off and lay a finger across the bottom can you focus on your finger?

 

[PatrickT]

Yep! I haven't tried focusing on my finger, but the rest of what you said is true. Focuses fine without the prism, big rounded glass, etc.

 

[dpurdy]

Focusing on your fingers is an important test. If you can focus them laid right across the bottom then the prism and diopter should be fine. If you have to move your fingers away from the bottom to get in focus or push them up into the prism to get in focus it might tell you that there is some plus or minus diopter in place. It is possible that a custom diopter was made. Otherwise I am stumped.
Dennis

 

[Diapositivo]

I would just go to my optician. Opticians normally have some optometry instruments. Ask them to try some lenses (you know, the set of lenses they put in front of your eyes when they measure your sight) in front of your viewfinder. You should find in a minute if there is a dioptre improving things, and which value it is. Then buy some film as the optician was so nice

Fabrizio

PS Contact lenses are a great invention. I now stay home most of the time and find contact lenses some kind of a hassle but when I worked outside contact lenses were comfortable and - especially - they seem to disturb focusing much less. If you are short-sighted, and wear contact lenses, you will strain your eyes less when reading near. Can't offer a scientific explanation, but the effect was clear to me.

For instance, when working at the computer screen I find uncomfortable to wear my glasses (-2). When I wear contact lenses (-2) I don't find uncomfortable at all looking at the monitor.

 

[PatrickT]

Ah ha!

So it turns out there was a piece that screwed into the eyepiece that apparently has a diopter correction factor to it (and also has the rubber "cup). When I discovered that they were two separate pieces, I unscrewed it and voila...now I can see.

Are all of these two pieces or was my additional piece just added?

Here's how the prism looks without the extra piece screwed in:

(sorry for the crappy photos).

 

[dpurdy]

Well if it works it works but I am still a bit confused. My stock eye piece looks like the one on the left side of your two pictures of the elements. It has just one lens in it and that is on the side that screws into the prism first. My old style +1 is the same except that it has a plus 1 painted on the outside face. My new style +1 has the diopter screwed into the piece from the outside end rather than the inside end. Both styles, in +1 or stock, have only one lens, only one piece of glass. So if I was to take it apart as you have done I would merely be taking the eye cup off, which would have no affect on the focus. Your bottom picture of the prism on the camera seems to have no eye piece lens in at all... which would make it unfocusable at least for me. But whatever, if it works for you it works.
Dennis

 

[Diapositivo]

Are all of these two pieces or was my additional piece just added?

I suppose there must be one, and only one, peace of glass. No glass would let dust in. Two glasses would make for unnecessary reflections. (I know, normally SLR have the standard glass, and you ADD another dioptre in front of it, which is not optimal. Cameras that allow you to regulate the dioptre are better).

So there probably is one glass that is normally 0 or -1. If the person you bought it from needed a different correction, he substituted the glass with one that does not match your sight, and your problem now is to find the correct power for your eyes.

 

[PatrickT]

Actually there are TWO pieces of glass...one in the eyepiece, and one on the screw in piece. In the photos above, each piece has some glass in it. The one that screws unto the prism is a mostly clear piece of glass, while the other one looks like it has some correction to it.

However, the glass in the piece on the right looks like it might have been glued in...not sure. Where it mounts to the eyecup looks rather messy like someone did a bad job of putting it in. Perhaps the previous owner made his own diopter with the eyecup screw in piece?

 

[dpurdy]

That answers it then. Someone needed a different diopter and couldn't find what he needed so he had made or made himself a diopter to fit and glued it in place. Since the original eyepiece has a lens that can't be removed, if you can't find a diopter for it that is what you need to do. I'm glad you figured it out.
Dennis

 

[PatrickT]

That must be it. Thanks for all the help!

 

[ic-racer]

What are you going to do with the extra diopter? I have been looking for one.