The opposite of a close-up lens?
 

I've just found out that my new camera (Noblex 150E) is short-sighted by
design. Well, they call it "hyperfocal focussing". We don't even have a
word for this nonsense in German.

Pulled the first film through it, last weekend, and if there's anything
that really annoys me then it's landscape pictures which aren't
perfectly sharp at infinity.

Now, given that human short-sightedness can be corrected quite
satisfactorily with glasses, is there a possibility of doing the same
with a camera and what would be the effect on the optical performance?

Ralf

--
Ralf R. Radermacher - DL9KCG - Köln/Cologne, Germany
private homepage: http://www.fotoralf.de
manual cameras and photo galleries - updated Feb. 23, 2004
Contarex - Kiev 60 - Horizon 202 - P6 mount lenses

The opposite of a close-up lens?
 

"Ralf R. Radermacher" wrote in message
...
I've just found out that my new camera (Noblex 150E) is short-sighted by
design. Well, they call it "hyperfocal focussing". We don't even have a
word for this nonsense in German.

WissenschaftKameraobjektiv ungenau ?

Pulled the first film through it, last weekend, and if there's anything
that really annoys me then it's landscape pictures which aren't
perfectly sharp at infinity.

"Hyperfocal" - "The prime focal spot is somewhere between here and infinity
but we won't tell you where 'here' is."

Now, given that human short-sightedness can be corrected quite
satisfactorily with glasses, is there a possibility of doing the same
with a camera and what would be the effect on the optical performance?

Actually, the current treatment is to put a patch over good bad eye. Rather
bad news for a Cyclops, eh?

No help, certainly. I look forward to intelligent responses.

The opposite of a close-up lens?
 

In article ,
"jjs" wrote:

No help, certainly. I look forward to intelligent responses.

The opposite of the close up lens is the minus lens series. To use them
you usually need a bellows focusing camera.

--
To reply no_ HPMarketing Corp.

The opposite of a close-up lens?
 

(Ralf R. Radermacher) wrote in message ...
I've just found out that my new camera (Noblex 150E) is short-sighted by
design. Well, they call it "hyperfocal focussing". We don't even have a
word for this nonsense in German.

Pulled the first film through it, last weekend, and if there's anything
that really annoys me then it's landscape pictures which aren't
perfectly sharp at infinity.

Now, given that human short-sightedness can be corrected quite
satisfactorily with glasses, is there a possibility of doing the same
with a camera and what would be the effect on the optical performance?

Ralf

Ralf:
I assume that you've got a "normalish" lens such as a Tessar with a
modest field of view. Depending on where the focus point is set, you
should be able to install a weak plano-concave or bi-concave negative
lens to regain true infinity focus. However, depending on the field
of view and f/# you may notice some off-axis degradation due to
astigmatism if the power gets much beyond 1/4 diopter. I would not
expect much change in on-axis performace even at large apertures. A
much better alternative, if its feasible with your camera, is to
refocus the lens. If you're lucky, the lens assembly will be threaded
into place and held fixed by a lockring.

Brian
www.caldwellphotographic.com

The opposite of a close-up lens?
 

brian wrote:

I assume that you've got a "normalish" lens such as a Tessar with a
modest field of view.

It is in fact a Tessar type but at a focal length of 50 mm for a
medium-format camera it isn't exactly what one would call "normalish".

Ralf

--
Ralf R. Radermacher - DL9KCG - Köln/Cologne, Germany
private homepage: http://www.fotoralf.de
manual cameras and photo galleries - updated Feb. 23, 2004
Contarex - Kiev 60 - Horizon 202 - P6 mount lenses

The opposite of a close-up lens?
 

The opposite of a close-up lens?
 

"Ralf R. Radermacher" wrote in message
...
brian wrote:

I assume that you've got a "normalish" lens such as a Tessar with a
modest field of view.

It is in fact a Tessar type but at a focal length of 50 mm for a
medium-format camera it isn't exactly what one would call "normalish".

A 50mm WA on an old MF camera? Sounds like it's got the wrong lens!

The opposite of a close-up lens?
 

jjs wrote:

A 50mm WA on an old MF camera? Sounds like it's got the wrong lens!

I do beg your pardon?

Ralf

--
Ralf R. Radermacher - DL9KCG - Köln/Cologne, Germany
private homepage: http://www.fotoralf.de
manual cameras and photo galleries - updated Feb. 23, 2004
Contarex - Kiev 60 - Horizon 202 - P6 mount lenses

The opposite of a close-up lens?
 

"Ralf R. Radermacher" wrote in message
...
jjs wrote:

A 50mm WA on an old MF camera? Sounds like it's got the wrong lens!

I do beg your pardon?

Okay, I missed the post where you identified this camera. I thought it was
an old folder or something, and since it only has hyperfocal focusing, I
presumed it was an inexpensive camera, and I am ignorant of any old,
inexpensive Wide Angle fixed-focus cameras.

So, where are we now? What's the format again? 50mm? Brand? (I can't back up
to see the old message)

The opposite of a close-up lens?
 

jjs wrote:

So, where are we now? What's the format again? 50mm? Brand?

Noblex 150E. 5 x 12 cm. Rotary lens panoramic camera using 120 film.

Ralf

--
Ralf R. Radermacher - DL9KCG - Köln/Cologne, Germany
private homepage: http://www.fotoralf.de
manual cameras and photo galleries - updated Feb. 23, 2004
Contarex - Kiev 60 - Horizon 202 - P6 mount lenses