PhotoBanter.com

PhotoBanter.com (http://www.photobanter.com/index.php)
-   Digital SLR Cameras (http://www.photobanter.com/forumdisplay.php?f=21)
-   -   Are primes brighter and sharper than wide open zooms (http://www.photobanter.com/showthread.php?t=49519)

no_name September 30th 05 04:41 AM

Dave Martindale wrote:

no_name writes:


(It's almost
like the old question about a pound of lead and a pound of feathers -
they do both weigh the same.)



However, a pound of gold and a pound of feathers do not.



Due to the archaic system of weights&measures that uses a different unit
with the same name for measuring precious metals.

But a gram of gold and a gram of feathers *are* the same mass, and have
the same weight in the same gravity.

Dave


OTOH, "the old question" was weight not mass.

Pete D September 30th 05 04:43 AM


"Chris Brown" wrote in message
...
In article ,
Tony Polson wrote:

Since there is no accepted definition of a "prime" lens we should just
drop the term, as it serves only to confuse.


Feel free to go ahead. The rest of the world will carry on using it.
You're
tilting at windmills.


IAWCB, I vote to not care what they call non zooms and non fixed lenses! ;-)



Paul J Gans September 30th 05 05:44 AM

In rec.photo.digital.slr-systems Tony Polson wrote:
Eugene wrote:

I don't think it has anything to do with the internet really. They've
been called prime lenses for as long as I can remember, and yes I do
pre-date the Internet ;-)



If only it was as simple as referring to all fixed focal length lenses
as "prime" lenses. Most subscribers to this newsgroup probably aren't
old enough to recall that some manufacturers used the term "prime" to
refer to a high quality subset of their fixed focal length lenses.


What made a particular fixed focal length lens design a "prime" lens
was not clear. Why other fixed focal length lenses were not described
as "prime" lenses was even less clear. But what is clear is that
assuming all fixed focal length lenses were referred to as "prime"
lenses is wrong. It was marketing, pure and simple.


Since there is no accepted definition of a "prime" lens we should just
drop the term, as it serves only to confuse.


I like the idea of FFL and VFL, especially as so many VFL optics are
not true zooms because they do not hold focus when zoomed. They are
often termed vari-focal lenses (also "VFL"), which term could be
extended to include the true zooms.


FFL and VFL has my vote.


;-)


I dimly recall the term "prime lens" as being the
lens whose focal length was equal (at least roughly)
to the diagonal of the film frame. That made a 50mm
(or 45mm) lens "prime" for 35mm film.

A 135mm lens was then a "telephoto" and a 35mm lens
was a "wideangle".

Zoom hadn't been invented yet.

By the way I find acronyms very hard to remember (VHR).
I much prefer a pronoucible name. Most acronym
users seem to as well, since they often make the
acronym pronouncible.

---- Paul J. Gans


Peter September 30th 05 05:57 AM


Paul J Gans wrote:

I dimly recall the term "prime lens" as being the
lens whose focal length was equal (at least roughly)
to the diagonal of the film frame. That made a 50mm
(or 45mm) lens "prime" for 35mm film.


The usual term for this is "normal lens"


A 135mm lens was then a "telephoto" and a 35mm lens
was a "wideangle".


A telephoto lens, properly speaking, is one in which
the lens (when set to infinity focus) is closer to
the film/sensor than the focal length of the lens.

It is quite possible to have a wide angle lens
which is of telephoto constuction. Olympus compacts
have had such lenses for years. On an Olympus XA,
the point 35mm in front of the film is actually
just in front of the front element of the lens.

A lens which is significantly longer than a normal
is called a long-focus lens if it is not of telephoto
design.

Wide angle lenses for SLRs are generally of an
inverted telephoto type in which a point one
focal length in front of the film may be somewhat
behind the rear element of the lens.

Peter.
--



Eugene September 30th 05 06:26 AM

Isn't that what's refered to as a "standard" lens?


I dimly recall the term "prime lens" as being the
lens whose focal length was equal (at least roughly)
to the diagonal of the film frame. That made a 50mm
(or 45mm) lens "prime" for 35mm film.

A 135mm lens was then a "telephoto" and a 35mm lens
was a "wideangle".

Zoom hadn't been invented yet.

By the way I find acronyms very hard to remember (VHR).
I much prefer a pronoucible name. Most acronym
users seem to as well, since they often make the
acronym pronouncible.

---- Paul J. Gans


Tony Polson September 30th 05 11:07 AM

"Peter" wrote:


Paul J Gans wrote:

I dimly recall the term "prime lens" as being the
lens whose focal length was equal (at least roughly)
to the diagonal of the film frame. That made a 50mm
(or 45mm) lens "prime" for 35mm film.


The usual term for this is "normal lens"




.... or "standard lens", which is common usage in the UK.



Chris Brown September 30th 05 11:57 AM

In article ,
Nostrobino wrote:

Well, not necessarily, though of course the more people who misuse the term,
the harder it will be to correct it.

Most people do not want to use wrong terminology since it makes them look
ignorant. In the case of "prime" being used to mean FFL, this has only
spread because readers who have not seen the term before, and then see it
used by people they assume are knowledgeable, naturally adopt it themselves.


I know this may give you apoplexy, but my nice shiny EOS 5D which I bought
yesterday includes, in the box, an accessories catalogue from Canon, which
amongst other things features a complete list of their current EF lens
range. They split it up into the following categories (from memory):

Zoom
Macro
Tilt and Shift
and, yes, Prime, which lists all of their fixed-focal length lenses (apart
from the Macros and T&S).

So at least one manufacturer is using the term to mean fixed-focal length.

Peter September 30th 05 02:28 PM


Chris Brown wrote:

I know this may give you apoplexy, but my nice shiny EOS 5D which I bought
yesterday includes, in the box, an accessories catalogue from Canon, which
amongst other things features a complete list of their current EF lens
range. They split it up into the following categories (from memory):

Zoom
Macro
Tilt and Shift
and, yes, Prime, which lists all of their fixed-focal length lenses (apart
from the Macros and T&S).

So at least one manufacturer is using the term to mean fixed-focal length.


I am willing to bet that some (possibly all) of the "macro" lenses
in the brochure are not really macro lenses intended primarily for
1:1 and greater magnification.

I would not be even slightly surprised if the word "telephoto" were
used more than once in the brochure to describe something that is
not actually a telephoto lens.

If you get your terminology from advertising literature, you are
probably going to get it wrong.

Peter.
--



Chris Brown September 30th 05 02:43 PM

In article .com,
Peter wrote:

Chris Brown wrote:


Macro
Tilt and Shift
and, yes, Prime, which lists all of their fixed-focal length lenses (apart
from the Macros and T&S).

So at least one manufacturer is using the term to mean fixed-focal length.


I am willing to bet that some (possibly all) of the "macro" lenses
in the brochure are not really macro lenses intended primarily for
1:1 and greater magnification.


Actally they are. Canon have lots of lenses with so-called "Macro" zones on
their focus ring, which aren't actually 1:1, but AFAIK all the lenses in the
"Macro" category are true 1:1 or greater lenses.

I would not be even slightly surprised if the word "telephoto" were
used more than once in the brochure to describe something that is
not actually a telephoto lens.


If you're going to object to the "misuse" of telephoto, you're fighting a
cause which is even more lost than the "prime" caus. I rather suspect that
the vast majority of non-LF photographers don't actually even understand
that it ever had a different meanning to its current one. What woul dyou
have people call what the whole world and their granny now calls "telephoto"
lenses? Narrow-angle, perhaps?

If you get your terminology from advertising literature, you are
probably going to get it wrong.


If you want to be prescriptive about language, then you're off to a really
bad start by chosing English to fight your battle in. Perhaps you'd have
better luck with Latin?

Peter September 30th 05 03:41 PM

Chris Brown wrote:
In article .com,
Peter wrote:


I am willing to bet that some (possibly all) of the "macro" lenses
in the brochure are not really macro lenses intended primarily for
1:1 and greater magnification.


Actally they are. Canon have lots of lenses with so-called "Macro" zones on
their focus ring, which aren't actually 1:1, but AFAIK all the lenses in the
"Macro" category are true 1:1 or greater lenses.


I think you misunderstand me. A _real_ macro lens is not one
which has a focus ring which goes up to 1:1, but a lens which
is primarily intended for 1:1 or greater magnification.

Real macro lenses have names on them like:
Leica (or Leitz) Photar
Leitz Micro-Summar (old)
Carl Zeiss Luminar
Carl Zeiss Jena Mikrotar
B&L Micro-Tessar (old)
Nikon (or Nippon Kogaku) Macro-Nikkor

They usually have no focusing ring and very often have the
same thread mount as microscope objectives. The old Leitz
Micro-Summars and B&L Micro-Tessars can often be had
quite cheaply, the modern ones tend to be very expensive.

Nikon is unusual in that they reserve the word "macro" for their
true macro lenses. Nikon uses "Micro-Nikkor" for their lenses
designed for normal close-up work.


I would not be even slightly surprised if the word "telephoto" were
used more than once in the brochure to describe something that is
not actually a telephoto lens.


If you're going to object to the "misuse" of telephoto, you're fighting a
cause which is even more lost than the "prime" caus. I rather suspect that
the vast majority of non-LF photographers don't actually even understand
that it ever had a different meanning to its current one. What woul dyou
have people call what the whole world and their granny now calls "telephoto"
lenses? Narrow-angle, perhaps?


Narrow-angle it could be, and I have seen it used, but the normal
expression is "long-focus lens." As I posted in another part of
this thread, Olympus has made compact 35mm cameras for years which
have 35mm telephoto lenses on them which are thus both wide-angle
and telephoto. I know the lens on the Olympus XA was like this and
I believe it is also true for the Stylus Epic.

If you get your terminology from advertising literature, you are
probably going to get it wrong.


If you want to be prescriptive about language, then you're off to a really
bad start by chosing English to fight your battle in. Perhaps you'd have
better luck with Latin?


Some battles in camera language have been won by the purists.
It used to be really common in the first half of the twentieth
century to use "Depth of Focus" incorrectly for the depth on the
object side of the lens. The purists won, and practically everyone
gets the "depth of field" vs. "depth of focus" distinction correct
nowadays. If you doubt me on this, look in a Leica Manual from
1935 to 1947 where the writers get the terminology wrong. In the
1951 and later editions, as well as almost any modern photography
book, the terms are used correctly.

Peter.
--




All times are GMT +1. The time now is 04:32 PM.

Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
PhotoBanter.com