Lenses that function best wide open

Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon stopping
the lens down.
If so, what lens, and what camera was it used with?

Rich wrote:
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon stopping
the lens down.
If so, what lens, and what camera was it used with?


The super telephotos from Nikon and Canon work superbly
wide open, and do not change much when stopped down.
E.g. 500 mm f/4, 600 mm f/4.

Roger

"Rich" wrote in message
ups.com...
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon stopping
the lens down.
If so, what lens, and what camera was it used with?


85mm Pentax F1.4 is amazing and has been tested on a 5D and compared to the
Canon 85mm F1.2 at F1.4, the Pentax was sharper, gotta be happy with that??
I posted the link a week or two back.

Rich wrote:
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon
stopping the lens down.
If so, what lens, and what camera was it used with?

Most lenses are designed to work over a range of apertures. The
designers work to provide the best overall image and they don't know what
aperture they will be used at. So as a result they generally aim for a
centralist approach. They work to have the center range the best and the
extremes will be less so. That works both ways wider and stopped down.

Special purpose lenses are likely to be optimized for their designed
use. There were some lenses made that did not even have a method of
stopping them down. You may own one. The mirror lenses that were popular
30 years ago were like that. They were optimized for their max and only
aperture.

--
Joseph Meehan

Dia 's Muire duit

"Rich" wrote in message ups.com...
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon stopping
the lens down.
If so, what lens, and what camera was it used with?

Some micro lenses and special-use lenses (like the Nikkor
55mm f1.2 for oscilloscopes) perform best (or nearly so)
wide open (though these cannot be directly mounted to
cameras without adapters and extensions). Teles are often
fine wide-open (the 85mm f1.8AF, 135mm f2MF, and
180mm f2.8AF Nikkors are really excellent wide open,
as are most of the longer, fast Nikkors. The 16mm f3.5
Nikkor fisheye is a great lens, nearly at its best wide open
(amazing for a super-wide!). Many other Nikkors are
excellent nearly wide open (most of these are non-zooms,
though...). You may find my Nikkor list interesting, at --
http://www.ferrario.com/ruether/slemn.html
--
David Ruether


http://www.ferrario.com/ruether

Rita Ä Berkowitz wrote:
Don't forget the 85mm f/1.4 Nikkor, plus a few other Nikkors, that are
sweet
on the 5D.

Hi, Rita.

You've mentioned this a couple times, and I'm curious... I thought the
focal planes couldn't align with an adapter ring, but maybe that's just
with Canon lenses on Nikon bodies?

Are you using an adapter, or can Nikon F-mount lenses mate directly to
the EF body? What are the tradeoffs? (manual focus / aperture /
metering? No lens data in EXIF?)

Cheers,
Richard

Joseph Meehan wrote:
Rich wrote:
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon
stopping the lens down.
If so, what lens, and what camera was it used with?

Most lenses are designed to work over a range of apertures. The
designers work to provide the best overall image and they don't know what
aperture they will be used at. So as a result they generally aim for a
centralist approach. They work to have the center range the best and the
extremes will be less so. That works both ways wider and stopped down.

Special purpose lenses are likely to be optimized for their designed
use. There were some lenses made that did not even have a method of
stopping them down. You may own one. The mirror lenses that were popular
30 years ago were like that. They were optimized for their max and only
aperture.

--
Joseph Meehan

Dia 's Muire duit

This is kind of interesting. Right now, you can buy a hyperbolic
astrograph (a mirror lens) with a 500mm focal length and an f2.8
aperture. It costs about $4,500 and will support up to a 35mm image
size. I would like to compare that to a fast refractive optic to see
which would yield the best results. The astrograph would not suffer
from any CA or related aberrations. Both lenses however are likely
made to operate best at infinity with close distances (under 100 feet)
causing increasing spherical aberration to been seen.
In that case, you'd stop them down to improve it.

"Rich" wrote in message
ups.com...
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In
other words, the residual aberrations don't decrease noticeably
upon stopping the lens down.

Well, actually the residual aberrations continue to improve (as more
edge rays are excluded from 'contributing'), but they will get
overwhelmed by diffraction.

If so, what lens, and what camera was it used with?

Besides the longer focal lengths, and assuming lenses capable of
relatively wide apertures like f/2.8, my T/S-E 45mm f/2.8 already
peaks af f/4.0 and gradually drops in peak MTF response in the optical
center when used on a Canon 1Ds Mark II body.

I'd have to test it further for corner performance, which would
involve shifting to the extremes of its image circle range. I assume
it will peak in the extreme corners where diffraction will overtake
residual lateral chromatic aberrations at approx. f/11.0 .

--
Bart

Rich wrote:
Joseph Meehan wrote:
Rich wrote:
Has anyone ever run across any lens (outside of very long ones,
exceeding f10 focal ratios) that performs best wide open? In other
words, the residual aberrations don't decrease noticeably upon
stopping the lens down.
If so, what lens, and what camera was it used with?

Most lenses are designed to work over a range of apertures. The
designers work to provide the best overall image and they don't know
what aperture they will be used at. So as a result they generally
aim for a centralist approach. They work to have the center range
the best and the extremes will be less so. That works both ways
wider and stopped down.

Special purpose lenses are likely to be optimized for their
designed use. There were some lenses made that did not even have a
method of stopping them down. You may own one. The mirror lenses
that were popular 30 years ago were like that. They were optimized
for their max and only aperture.

--
Joseph Meehan

Dia 's Muire duit

This is kind of interesting. Right now, you can buy a hyperbolic
astrograph (a mirror lens) with a 500mm focal length and an f2.8
aperture. It costs about $4,500 and will support up to a 35mm image
size. I would like to compare that to a fast refractive optic to see
which would yield the best results. The astrograph would not suffer
from any CA or related aberrations. Both lenses however are likely
made to operate best at infinity with close distances (under 100 feet)
causing increasing spherical aberration to been seen.
In that case, you'd stop them down to improve it.

But mirror lenses have a constant aperture (can't be adjusted)...

--
Images (Plus Snaps & Grabs) by Mark² at:
www.pbase.com/markuson

On Sun, 26 Nov 2006 16:41:46 -0800, "Mark²" who knows not how to
squint mjmorgan(lowest even number wrote:

This is kind of interesting. Right now, you can buy a hyperbolic
astrograph (a mirror lens) with a 500mm focal length and an f2.8
aperture. It costs about $4,500 and will support up to a 35mm image
size. I would like to compare that to a fast refractive optic to see
which would yield the best results. The astrograph would not suffer
from any CA or related aberrations. Both lenses however are likely
made to operate best at infinity with close distances (under 100 feet)
causing increasing spherical aberration to been seen.
In that case, you'd stop them down to improve it.

But mirror lenses have a constant aperture (can't be adjusted)...

Same with LensBabies. But they have a method of reducing aperture
that with a little adapting could also work for mirror lenses.