Oh! Dear ....... Does this mean that the great Ansel Adams was
wrong as well as me! From "The Print" and remember he was using
10x8 high quality contact prints direct from 10x8 negatives and
had a very good eye .....

"To obtain a literal view of the perspective, then view the image from a distance that is the same as the focal length of the lens that was used to take the picture."
Also stated is that "If the print is enlarged 2 times then also double the viewing distance to keep the same perspective."

So if your trying to compare different FL's...... some enlarged
you can't look at them all from the same distance So that
invalidates the usual every lens has the same perspective illusion

App to calculate viewing distances.....
http://visualimpact.anl.gov/pvdcalc/index.cfm

Viewing distance = focal length x degree of enlargement seems
quite popular.

This guy has actually done some test shots comparing prints to
actual....
http://www.grahamreedlightingcameraman.com/articles.htm

http://www.grahamreedlightingcameraman.com/articles/perspective.pdf

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If I'm wrong all the old Photo magazines are wrong as well

It was always advised, particularly with 135mm portraits to
look at them from a considerable distance a hand held 10x8
looked horrible if you didn't on the other hand a postcard
size print looked great handheld. This is why an 85mm lens
was preferred for portraits 10x8's handheld looked better
than 135mm's

Probably someone on a Leica forum could explain better.

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I agree John although I am surprised that considering
you once used film you seem to have forgotten that to appreciate
perspective such as a life size 135mm portrait you have to stand at
the same distance that it was taken from or it will look flat.
If you enlarge twice as big you have to stand 2x the distance.

To appreciate a WA shot you should position your eye closer
to the print to see a more normal perspective.

For the same reason you can't compare side by side two shots
taken with different focal lengths, because they require
different viewing distances.

Roughly speaking if you view a WA shot close up and a Tele
shot from a distance they should look the same. That's also
how panorama stitching works.

There is no way a distorted WA shot can be produced by a Tele lens

It's pointless discussing perspective in the digital world
when people (unfortunately) only see 2D.

So less of this talk about photography and lets all get back to
buying equipment and blaming Ricoh

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That's a nice magicians trick Tony You've magnified
one of them The one John posted has also been magnified
John's also has very little info in the 3rd dimension, (no depth)
which makes it hard to tell what lens it was taken with.

I could use the same trick to prove that a 1 foot and a 2 foot
length of wood are the same size by taking 2 photos and doubling the
size of the 1 foot piece of wood to match the 2 foot one on the
screen.

Back in the film days it was quite common for students to be
asked what FL's had been used to take pictures and it was the
24/28mm lenses that made Sunday Colour Supplements very popular.

Try taking a set of pano photos with alternating WA and Tele
shots then combine them without altering the magnification
and see what you get.

Would you say the perspective of these two lenses was the same...
http://www.dpreview.com/forums/thread/3386079
Note the angles of the rails.

Why is it that when you use a WA lens to photograph a building
you have to be EXTRA CAREFUL to have it vertical or it will
have badly converging verticals whilst you don't have to be
as fussy with a standard lens and even less with a tele?
Obviously the perspectives aren't the same.

I did mention in other posts that probably due to digital
displays photographers have mostly lost their seeing eye
for things like perspective. Painters on the other hand
have highly trained eyes and have developed techniques
such as foreshortening. I would say the figure at the
start of this tutorial looks like a WA shot, but if all
lenses produce the same perspective it could be a 500mm
Tele

No doubt you will all be happy when sensors become so good
that you will only need 1 lens say a 15mm and just crop
every shot to match Normal and Tele lenses

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If you cropped the WA shot of the man to just his head and
shoulders... his head would be too big for his shoulders.
If you also took a Tele shot from the same distance his head
and shoulders would look OK. There would be some distortion, but
it would be acceptable.

You need to understand that tele-shots are magnified and the
distance compressed. If you look at your finger through a 2X
magnifying glass... It not only looks bigger... it also looks
closer.

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There seems little point in taking this topic any further. It's
beyond the scope of this forum.

I've just looked again at the Photozone article and it just about
covers everything and is spot on. They (Photozone) are a Team of at
least 3 professional people who are friendly with quite a lot of top
names in photography such as Falk and I'm sure any errors would have
been discussed and rectified.

An important statement I missed at first is "The longer the focal length
the more jumps the church (background object) towards the lamp -
the perspective gets COMPRESSED."

Tele compression is accepted everywhere (except here) and because
the 3rd dimension has been compressed relative to the focal length
it can't be derived from or converted to another focal length.


Going back to this WA photo link
It's obvious due to the extreme WA distortion you can't crop it
and get a Tele view. If you crop off just a hand, the fingers are
bigger than the thumb. You could also use a smaller cropped format
and capture just say the hand and it would show the same distortion
which confirms that it is the lens that causes the perspective.

I won't be posting anything further in this thread because it's
fully covered by Photozone and my original post was just to confirm
that they were right. The sketch I did would have
been better with street lights the same as they have.

The Mods need to be a bit more careful about what is said
on here about Photozone. It seems libellous to me.

--

This video shows it done by a photographer with different lenses.
Not as good as the racing, but might help some people.
Notice that on the Tele shots (200mm) the crowd
behind don't look to have much room. You can't achieve
that by enlarging a WA shot.

http://www.youtube.com/watch?v=7Fzh9eQDhL4

Also note WA shots have a greater DOF.

All this was well covered on the TP Forum someone
took shots from high up looking down on a row of
terraced houses from the back showing a lot of
parallel lines including railway lines. They
enlarged the WA shots, but they were miles away from
being the same as the Tele shots. I can't find it
via Google and have a feeling that TP don't keep
everything in their archive. I never bookmarked it
because it only confirmed what I already knew.

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It's certainly not an optical illusion. I don't know why photographers
can't see it. but the average Joe or Beryl can. If I give them a camera
with a 300mm lens to have a look through they immediately say
"It brings everything closer" which it does and it does it by
magnifying the image..... Like all magnification it does that
by making the distance look smaller than it actually is.
With a 10X magnification every step forward of 1M will look
like 0.1M through the viewfinder or binoculars. It can't
be achieved from magnifying a WA view because the distance
information isn't correct.

Horse racing on TV shows this up well. The stuff on Youtube
isn't as good, but this one shows the horses moving very
little approaching the camera and by much more as they
pass it.

http://www.youtube.com/watch?v=oHE_LQjfuuM

This one might be a bit better.....
http://www.youtube.com/watch?v=g-TEyesFK8g

So Tele lens shots are unique in that they have
normal 2D distance information L/R Up/Down but
compressed distance information Near/Far which
can be clearly seen on the horse videos.

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Because I get the same effect if I look through a pair of binoculars
that have 10X written on them and I don't get that effect if I look
through a cardboard tube. It's all to do with magnifying lenses.
It's also noticeable on car wing mirrors if they are magnifying
ones other cars look closer.

The effect is even seen in videos. In this one the rugby player
is running fast towards the camera, but because of tele compression
he doesn't look to be moving much.....

http://www.youtube.com/watch?v=ahR6qHcONu8

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This is a good example of telephoto compression.....
http://www.flickr.com/photos/unclejefejefe/4594201017/

The cars look on top of one another and the pedestrians look
very similar in height. Notice also the steep angle of the
kerblines........ Quite obvious that this couldn't be part
of a WA shot blown up.

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