Newbie question: lenses

Hi. I'm brand new to LF, and just bought my first camera and lens. I have a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior. The
trouble is, I can't seem to find any information about it on the web. What I
did find conflicted with everything else. I'm looking for just the angle of
coverage and coverage at infinity focus. It was mere curiosity before; now
that I have it in my hands, I'm concerned. I have loupes with more glass
than this lens has; it's not at all what I was expecting. Is this reasonable
for a 4x5 wide angle lens? Will I get reasonable coverage and movement on
4x5? The camera hasn't arrived yet, so I'll have to wait a few more days to
find out. In the meantime, you can help drive me crazy with more rumors and
suppositions. What can you tell me about this lens I bought?

Thanks.
Mike.

"MikeWhy" wrote in message . com...
Hi. I'm brand new to LF, and just bought my first camera and lens. I have a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior. The
trouble is, I can't seem to find any information about it on the web. What I
did find conflicted with everything else. I'm looking for just the angle of
coverage and coverage at infinity focus. It was mere curiosity before; now
that I have it in my hands, I'm concerned. I have loupes with more glass
than this lens has; it's not at all what I was expecting. Is this reasonable
for a 4x5 wide angle lens? Will I get reasonable coverage and movement on
4x5? The camera hasn't arrived yet, so I'll have to wait a few more days to
find out. In the meantime, you can help drive me crazy with more rumors and
suppositions. What can you tell me about this lens I bought?

Thanks.
Mike.

Since I don't know what you expected its hard to address that. The
Angulon is a classic lens designed about 1929. It is a variation of a
type known as a Dagor. A Dagor is a lens with three cemented elements
in each cell. It is inherently a wide angle lens. While the powers of
the cemented elements in the Angulon are different from a Dagor its
properties are very similar. The outside elements of the Angulon are
made oversize to avoid mechanical vignetting (or shadowing) by the
lens mounting. The lens is also very slightly asymmetrical to improve
its performance for distant objects.
When the Angulon was first put on the market Schneider claimed a
coverage angle of 102 degrees at infinity focus. The lens will indeed
make a circle of light that big but the maximum coverage for good
image quality is only about 90 degrees. A 90mm Angulon will cover a
4x5 negative with just a little left over.
The original Angulon had a design defect. In fact, the design in the
patent is defective and very early Angulons evidently followed it.
These lenses have sever color fringing. Later Angulons (probably
within a couple of years) evidently used a revised design which does
not have this fault. I think (without looking) that this is actually a
fairly late lens.
More modern wide angle lenses have better performance than the
Angulon but the price is large size and weight. The Angulon actually
has very good performance. For maximum coverage it must be stopped
down a lot, around f/45 for 90 degrees, it will operate well at f/22
for smaller coverage. Its used wide open only for composing the image.
Some modern lenses employ a special design to reduce the fall off
of light with angle, the Angulon is too old to have this design so its
fall off is fairly severe. All "standard" design lenses fall off at a
rate proportional to image angle that is cos^4 theta, where theta is
the "half angle" that is the angular distance from the center of the
image to the point of interest. For a 90mm lens covering 4x5 (diagonal
of the film is 150mm) the angle is about 80 degrees and the fall off
is such that the corner illumination is about one third that of the
center.

Richard Knoppow
Los Angeles, CA, USA

Ah, someone else like me who buys first and asks questions later. : - )

I believe this lens has an image circle of 154mm and an 81 degree angle of
coverage (these numbers are taken from a secondary source, not from
Schneider, so it's possible they're off a little). Since 161mm is about the
size of the image circle required to cover 4x5 you won't get any movement
to speak of with this lens. It just barely covers 4x5 when stopped down.
However, many people happily use this lens for landscape work since
movements often aren't necessary with that kind of work and its small size
makes it ideal for backpacking. If you do architecture, product photography,
or anything else that requires movements you probably should return the lens
or buy a second one with room for more movements..

"MikeWhy" wrote in message
om...
Hi. I'm brand new to LF, and just bought my first camera and lens. I have
a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior.
The
trouble is, I can't seem to find any information about it on the web. What
I
did find conflicted with everything else. I'm looking for just the angle
of
coverage and coverage at infinity focus. It was mere curiosity before; now
that I have it in my hands, I'm concerned. I have loupes with more glass
than this lens has; it's not at all what I was expecting. Is this
reasonable
for a 4x5 wide angle lens? Will I get reasonable coverage and movement on
4x5? The camera hasn't arrived yet, so I'll have to wait a few more days
to
find out. In the meantime, you can help drive me crazy with more rumors
and
suppositions. What can you tell me about this lens I bought?

Thanks.
Mike.

"MikeWhy"

Hi. I'm brand new to LF, and just bought my first camera and lens. I have a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior. The
trouble is, I can't seem to find any information about it on the web. What I
did find conflicted with everything else. I'm looking for just the angle of
coverage and coverage at infinity focus. It was mere curiosity before; now
that I have it in my hands, I'm concerned. I have loupes with more glass
than this lens has; it's not at all what I was expecting. Is this reasonable
for a 4x5 wide angle lens? Will I get reasonable coverage and movement on
4x5? The camera hasn't arrived yet, so I'll have to wait a few more days to
find out. In the meantime, you can help drive me crazy with more rumors and
suppositions. What can you tell me about this lens I bought?

Thanks.
Mike.

You're running into the gray area with some older lenses. They may illuminate
a large area before cutting off. But no standard exists to define the point
were performance drops enough to be unusable and a cutoff marked. In fact the
unable/unusable point could vary depending on the image. So you may find
different figures quoted by different sources. I often wonder how they defined
this usable circle to the nearest mm. I believe that most modern lenses are
mechanically cutoff at a point the maker believes is the usable limit. Again
there is no standard between manufacturers to define this point. So when
comparing lenses you really have to look beyond just the claimed circle since
no one keeps makers from expanding it for marketing purposes.
Chuck

MikeWhy wrote:
Hi. I'm brand new to LF, and just bought my first camera and lens. I have a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior. The
trouble is, I can't seem to find any information about it on the web. What I


Schneider is one company that provides a lot of info on the web. Others
IMHO could learn from Schneider.

http://www.schneideroptics.com/info/.../6,8-90mm.html

Nick

Subject: Newbie question: lenses
From: "MikeWhy"
Date: 1/31/2004 12:11 AM Mountain Standard Time
Message-id:

Hi. I'm brand new to LF, and just bought my first camera and lens. I have a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior. The
trouble is, I can't seem to find any information about it on the web. What I
did find conflicted with everything else. I'm looking for just the angle of
coverage and coverage at infinity focus. It was mere curiosity before; now
that I have it in my hands, I'm concerned. I have loupes with more glass
than this lens has; it's not at all what I was expecting. Is this reasonable
for a 4x5 wide angle lens? Will I get reasonable coverage and movement on
4x5? The camera hasn't arrived yet, so I'll have to wait a few more days to
find out. In the meantime, you can help drive me crazy with more rumors and
suppositions. What can you tell me about this lens I bought?

Thanks.
Mike.


As you know this is an older lens and IMHO not a very good one.It has an image
circle of 154mm at f16. In reality it may be slightly more but not much. The
image at the edges of the image circle is also not very sharp and there is not
much you can do about this problem.The Super Angulon is a newer and much better
version of the same lens.

If you are going to be buying used lenses you might want to go back through
issues of View Camera magazine. Over the years we've run articles on most of
the lenses you will find out there.

If you are moving up and want to find lenses that are the equivilent focal
lengths to what you may have used in smaller formats there is a lens chart on
our web site in the Free Articles section.

www.viewcamera.com

Go to the Free Articles section in the black menu bar. There are several
articles that might be helpful to you.

steve simmons

PS


Hi. I'm brand new to LF, and just bought my first camera and lens. I have a
question about the lens, a Schneider Angulon 90mm f/6.8. I know it's old;
the serial number is is mid 5 million, making it a two years my senior. The
trouble is, I can't seem to find any information about it on the web. What I
did find conflicted with everything else. I'm looking for just the angle of
coverage and coverage at infinity focus. It was mere curiosity before; now
that I have it in my hands, I'm concerned. I have loupes with more glass
than this lens has; it's not at all what I was expecting. Is this reasonable
for a 4x5 wide angle lens? Will I get reasonable coverage and movement on
4x5? The camera hasn't arrived yet, so I'll have to wait a few more days to
find out. In the meantime, you can help drive me crazy with more rumors and
suppositions. What can you tell me about this lens I
bought?

I might suggest getting one of these books as they might be helpful as you dive
into large format

User's Guide to the View Camera by Jim Stone

Large Format nature Photography by Jack Dykinga

Using The View Camera that I wrote a few years ago.

All should be available from Amazon.com

There is another book that some people suggest called View Camera Technique. As
a reference this is very good. As a starter book it is a tome.

steve simmons

I believe this lens has an image circle of 154mm and an 81 degree angle of
coverage (these numbers are taken from a secondary source, not from
Schneider, so it's possible they're off a
little).

Any thought of identifying your secondary source? It might be helpful to the
questioner and to others who might have the same question if they new of a
place to go look for this type of info.

steve simmons

Largformat wrote:

Subject: Newbie question: lenses
From: "MikeWhy"
Date: 1/31/2004 12:11 AM Mountain Standard Time
Message-id:

Hi. I'm brand new to LF, and just bought my first camera and lens. I have
a question about the lens, a Schneider Angulon 90mm f/6.8.



If you are going to be buying used lenses you might want to go back
through issues of View Camera magazine. Over the years we've run articles
on most of the lenses you will find out there.



Or look here for some freely distributed information:

http://www.graflex.org/lenses/lens-spec.html

http://www.graflex.org/lenses/lens-faq.html

http://www.graflex.org/lenses/photog...-tutorial.html

http://www.hevanet.com/cperez/results.html

http://www.hevanet.com/cperez/testing.html

http://www.largeformatphotography.info/

http://www.bostick-sullivan.com/Alt_cameras/large format lenses.htm

http://www.f32.net/Services/Equipmen...lensspecs.html

http://medfmt.8k.com/mf/lflenses.html

The angulon can be good or poor depending on the sample you end up with.
Look at http://www.hevanet.com/cperez/results.html and see the variations
in results from different samples. This is true of most lenses especially
older ones. I would never buy a used lens (or new?) without some sort of
"return if it's a dud" warranty.

I'd consider the small size of the lens, whether you need movements and
finally testing the sample you are send and decide if it might be useful. A
SA has more coverage but is a MUCH larger and heavier lens.
--

Stacey

"BCampbell" wrote in message
.com...
Ah, someone else like me who buys first and asks questions later. : - )

I'd been lurking here for about a month now, and noted the relatively low
message volume. I absolutely didn't expect this gushing forth of on-topic
information. Wow. :-) Thanks, guys. All of it was useful.