Looks like 4/3 IS a "Crop"

Maxven · Mar 13, 2003

Joseph, if what you're saying is true then there's no more reason to call it 4/3 than there would be calling it 5/3 if they choose to make a body with a larger sensor, right? Granted, that negates the point of a whole new digital standard (except for the open standard mount). On the other hand maybe Oly's covering their bases in case sensor technology doesn't keep up, i.e. 4/3 will be too small for most people when FF or 1.3x FOV becomes less then $2K.

But IF you're correct what should sway people in Oly's direction? The 28-108mm isn't available on anything but FF but apart from that one lense (which Canon could probably make a 1.6x counterpart to) from going with the 10D with the choice of hundreds of existing lenses?

I'm no exert on these matters but are you saying that Oly's given up all the advantages they originally put forth in favour of the 4/3 system?

Regards, Maxven

Joseph S. Wisniewski said:
Gevork Mosesi said:

What you need to realize is that as long as you compare the two
formats, there will be a crop. The 4/3 lenses are specifically made
for the 4/3 sensor,

Click to expand...

This does not appear to be true.

Joseph S Wisniewski said:

therefore here is no crop and the ratio is 1:1.
The issue of crop only comes up when you use a lens that is made
for a 35mm format on a camera that has a smaller sensor than 35mm.

Click to expand...

That's what this situation appears to be.

Joseph S Wisniewski said:

In this case you will have a crop of for example 1.6 as in EOS D60.
So if you stop comparing formats, there wont be a crop. If that is
the case, 35 would be a crop of medium format, BUT they both
utilize their respective lenses, which makes each one of a 1:1
ratio.

Click to expand...

35mm would be a crop of medium format, if most 35mm lenses could
cover medoim format, and if the 35mm mounts, lenses, and cameras
were bigger than they needed to be because they utilized 35mm
components.

I've covered this in quite a bit of detail elsewhere in this
thread. But here's a quick summary.

1) The 4/3 system registration distance is considerably larger than
it needs to be. It is the same as a 35mm full frame SLR.

2) The lens mount diameter is also considerably larger than the 4/3
system needs, again it's the same as 35mm full frame.

3) Three of the four lens designs are obviously 35mm full frame
designs. The fourth appears to be only a slight modification.

4) Judging from the size of the camera, all the other components
are "borrowed" from 35mm systems, shutter, prism, mirror, focusing
screen.

So, the only reasonable conclusion is that the 4/3 system is,
indeed, a cropped 35mm system.

(Just as the Contax 35mm full frame digital SLR, with it's borrowed
medium format mount and lenses, could be considered a cropped
medium format, unlike the Canon and Kodak 35mm full frame digitals).

And here's a little more detail on the above points.

1) Olympus quite correctly points out that digital cameras perform
quite a bit better when their registration distance is increased
from what you would consider "normal" for an SLR, no matter what
format. Conventionals SLRs have registration distances roughly
equal to the diagonal of their image size. This is true for 110
format SLRs (1/2 the size of 35mm) on up to medium format SLRs (2x
or 3x the size of 35mm).

But Nikon, Canon, Fuji, and Kodak have proven that registration
distances 1.3x to 1.6x greater than the sensor diagonal are all you
need to overcome any difficulties with sensor vignetting due to
insufficiently perpendicular light. The 2x Oly mount (borrowed
directly from 35mm) is overkill and makes the camera thicker than
it has to be.

2) Although Olympus has provided valid reasons for a lens mount
that is greater than the diagonal of the sensor (as did Canon when
they designed the new EOS mount), they have again used a 35mm sized
mount, which is overkill for this system.

3) This has been covered in way too much detail already.
http://forums.dpreview.com/forums/read.asp?forum=1022&message=4587902

4) Several people have taken known data points (filter ring
diameters, flash shoe diameters) and scaled the "E system" camera
pictures to be in scale with pictures of other DSLRs like the
Pentax *ist-D or the Canon 10D. It's no smaller than a full sized
35mm. And it's obviouslt full of 35mm full frame components. look
at the prism housing. A 4/3 design that wasn't "cropped 35mm" would
have a prism 1/2 that size, sitting lower, closer to a mirror box
that was also 1/2 the size of a 35mm full frame. It would look more
like a rangefinder camera because the small prism, sitting lower,
would not rise above the top panel of the camera.

What Pentax is showing sure looks like a full sized 35mm prism,
sitting above a full sized 35mm mirror box, on a camera with a full
sized 35mm lens mount, and mostly full sized 35mm lenses.

In real life, in the face of so much evidence, no one could
possible say "It's not a crop" with a straight face.

But that's the nice thing about the internet. It's not real time.
Someone could be rolling on the floor, laughing, typing a little
every time they came up for air, and we wouldn't know it.

Ciao!

Joe

David Hughes124436 · Mar 13, 2003

TrentMcD said:
People know 35 mm so we use equivalences. There is a multiplier
that you can use to find the equivalent medium format lens for any
given 35mm lens size, so why does nobody call 35 mm a crop of
medium format?

Just a minor point: way back in the dim and distant past the people who used medium format (like 2¼" square) had no choice of lens (other than quality and price) worth mentioning and regarded themselves as a race apart from the 35 mm users. So the two developed (if that's the word) in completely different worlds and no one asked the equivalents as it was of no interest to either group.

Before someone jumps in and says it I'll point out that the price of a medium format camera was astronomical compared to 35 mm (apart from Leitz and a few others) and, yes, I do remember the SL66 which I regard as a modern camera. The days I am talking about were when pro's had two TLR's and one stand or technical camera and didn't pay any attention to 35 mm (apart from sneering at it) which was for amateurs and a few oddballs...

Luckily the oddballs were able to surpass them and convince people that 35mm was a serious format, but it was an uphill struggle.

Mikael Nordenberg · Mar 13, 2003

Joseph S Wisniewski said:
There is no need to shout. Calmly, look at the four lenses.

A 50mm f2.0 macro has a coverage circle at least as large as full
frame 35mm. The rear element is too close to the lens mount to
effectively baffle the lens down to a smaller coverage circle.

Seems reasonable. A 50mm isn't that large and bulky anyway, so
I'll be happy with a 35mm design.

Joseph S Wisniewski said:
A 300mm f2.8 telephoto has a coverage circle large enough for
medium format. Even on a 35mm camera this is a cropped lens.

I don't think they would produce a lens for 35mm that
has a coverage of medium format. This would make it
unnecessary bulky!

It's no big deal to adjust a 300mm f/2.8 designed for 35mm
to fit a smaller sensor. Some glass elements can be reduced in size
(depending if they are out of focus or not) to make the
image circle fit the sensor size. The front element cannot be
made smaller thogh, since it is completely out of focus, and
it would therefore make the lens slower.

Joseph S Wisniewski said:
There's virtually no way to design a 50-200mm zoom with a coverage
circle smaller than 35mm.

This is silly. Why should this not be possible?

Joseph S Wisniewski said:
The only lens that would have reduced coverage is the 14-52mm, and
that wouldn't take much work to adapt from a 35mm lens.

I think this is true also. But even though it's basically a 35mm
lens, it's still adjusted to utilize the 4/3 system.
(This will be a really nice lens!)

Joseph S Wisniewski said:
But having three of your 4 lenses as straight 35mm designs, and a
camera as big as a 35mm body (we would presume it's that big
because it's got a 35mm sized shutter, mirror, prism, etc). sure
does devine a crop.

Don't care too much about shutter, mirror etc. That can be fixed later.
Just make the lenses smaller and cover a reasonable zoom range!
I use a D30 now and there is NO lens to use as all-round lens.
The 19-35 is too wide in telephoto, and my 28-135 doesn't cover
enough wide.

Mikael

Mikael Nordenberg · Mar 13, 2003

Nope. That would be true if the 4/3 had the same
FOV using the 300mm lens on it as using a 300mm
on a 35mm camera.
But using the 300mm lens (for 4/3) on the 4/3
actually only gives half the FOV but remains at f/2.8.
(Which on the other hand requires the sensor to be
four times more sensitive.)

One could on the other hand redesign the lens to
do just what you say, act at the same FOV as a 300mm
on the 35mm (= 8.25 degrees), and then the lens
would be f/1.4.

Mikael

pocoapoco said:
pocoapoco said:

The smaller the sensor size, the smaller the angle of view.
The physical lens does not change: it's still a 300 mm 2.8 lens no
matter what sensor we put behind it.

Click to expand...

Then the 4/3 is a crop which is what the thread is about. but given
two lenses with the same light gathering power or same size front
element, and same focal length. If one lens focuses the light down
to an area which is one fourth the size of the area that the other
focuses down to ( in the case of †he 4/3 system vs 35mm format )
then the lux of the focused image will increase inversely or four
times as much. that's where the f 1.4 would come from. This is true
if indeed the 4/3 lenses do this. If not, then the 4/3 is really
just another dslr only with a 2x field of view crop instead of say
1.4 ,1.5,or 1.6 and not really anything special in and amongst
other dslr's.

Mikael Nordenberg · Mar 13, 2003

Well, the light collected to each point in the image
projection is the same no matter what sensor size
you use.

The speed doesn't increase at all. Actually the sensor
will have to be just as sensitive per pixel as the
"big brothers" (10D etc.), even though it's pixels are
smaller in size.

BUT if they succeed making a sensor that sensitive
(which they are planning of course, and I believe also),
all lenses will half the FOV compared to 35mm AND
still keep their f-stop limitations!

This would mean a 300mm f/2.8 will have the FOV
of a 600mm equivalent lens used on a 35mm system,
and still be f/2.8. (Haven't seen any 600mm f/2.8 on 35mm

Or using a front element the same size of the 300mm
f/2.8 they could produce a (probably shorter) lens
with the same FOV and f/1.4!

So as you can see it's actually the sensor that makes it
faster, not the lenses. It's all based on the assumption
that 35mm is unnecessary large for digital sensors.

Mikael

Trees said:
I'm no optical guru, but if the lenses are only cropping, how is
the speed better than the 35mm counterparts?

I'm not trying to be difficult, I'm really asking. Anyone know?

Is the lens on my E-10 REALLY something like an f4 17- 68, 35mm
lobbed on to a 2/3" chip? (not sure about the math here on the
focal multiplier)

Anyone care to make an un-educated guess?

Trees

Chris Charlton · Mar 13, 2003

Steven Noyes said:
True for the wide angle lenses for sure. No need on anything > 50mm.

Oh so I guess all that light can be thrown away and it will not effect the speed of the lens? I guess these Olympus designers are clever the way they bend the laws of physics..

Steven Noyes said:
Steven Noyes said:

therefore the amount of light per unit area is INCREASED, making
the lenses FASTER, so to get a reasonably fast lense like F2.8, the
lense designer can reduce the size of the whole thing, making it
SMALLER.

Click to expand...

This has NOTHING to do with it. The speed of the lens is dictated
two things only, the aperture and focal length. Image circle has
nothing to do with it. On standard through telephotos, the
aperture is the same diameter as the front lens element. As a
result the A MF 300mm f2.8, 35 mm 300mm f2.8, and APS 300mm f2.8
and the 4/3 300mm f2.8 can all be about the size and weight.

By your reasoning if I take a magnifiying glass and project a spot of the sun on the ground to burn a blade of grass, it makes no difference if I project a spot 3mm wide or 10mm wide, the light intensity will be the same amount?
Bending the laws of physics again?

Steven Noyes said:
A 300mm f2.8 is a 300mm f2.8 is a 300mm f2.8. The 4/3 system will
just be sampling a smaller section of the total image area. The
rest of the light goes to waste.

So all 300mm F2.8 project the same image size as the largest film available and then the sensor or film samples a smaller section of it? So you are saying all 300mm F2.8 lenses project an image circle about 12 inches across (to cover 8X10 film approx) and then they just sample a 35mm size film crop? or an APS size crop, or a 4/3 size crop?
Complete BS

Steven Noyes said:
The 4/3 system will be able to see benefits on wide angle lenses,
however. But not on telephotos. Not to say that a 300mm f2.8 on
the 4/3 system with 9 MP wouldn't be nice. But it will be NO
brighter than a 300mm 2.8 on a 35mm camera.

No it won't be any brighter than a 300mm F2.8 designed for a 35mm camera, it will be SMALLER....jeez....

Steven Noyes said:
Steven Noyes said:

The lenses will not cover the area required by a 35mm size sensor
(or film) they are designed ONLY for a 4/3 size sensor.
THERE IS NO CROP.....
I suggest if you don't understand this, don't buy any kind of
camera at all, because you will have many problems trying to

Click to expand...

Does this include you

You prove my point perfectly that Olympus will have a hard time explaining their system to the dumb uneducated masses....

Steven Noyes said:
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Jukka Jarnberg · Mar 13, 2003

It would be a crop if the lens would produce image circle for ex 43mm diameter and they'd put masking on to it reduce it to 23mm

But proposed lenses produce image circle approx 23mm and they utilize it fully then IT IS NOT CROP

GET IT!

Jukka

Joseph S Wisniewski · Mar 13, 2003

Maxven said:
Joseph, if what you're saying is true then there's no more reason
to call it 4/3 than there would be calling it 5/3 if they choose to
make a body with a larger sensor, right?

True. If they really do have a 35mm sized mount and film chamber, the basic camera should be good up to 1.5x sensors, like Nikon. (I won't say 1.3x sensors, like Canon, because the EOS mount is huge, bigger than anything else in the 35mm world).

Maxven said:
Granted, that negates the
point of a whole new digital standard (except for the open standard
mount).

Not really. If they decide to launch with just one sensor size (the way Nikon seems to be standardizing on 1.5x) then they can take advantage of a new format with just one set of new designs, one new prism, one new shutter, one new reflex mirror mechanism. Canon, for example, with their choice of 1.6x or 1.3x, could only make "optimally" small cameras if they designed two new shutters, two mirror mechanisms, two prisms, etc. A standardized sensor size saves on engineering.

Maxven said:
On the other hand maybe Oly's covering their bases in case
sensor technology doesn't keep up, i.e. 4/3 will be too small for
most people when FF or 1.3x FOV becomes less then $2K.
But IF you're correct what should sway people in Oly's direction?

Well, aside from the lens you mention, Oly has a history of making dang fine cameras, with some innovative lenses that have become true legends.

Ever used an OM series SLR? Oly did a fantastic job of making an SLR that size feel comfortable, workable even by big fumbly fingered folk, reliable, etc.

I hate to keep harping on the 250mm f2.0, but that lens is incredible. NASA called it the sharpest lens they've ever tested. Cinamatographers remount it and shoot movies through it.

I've used an oly 24mm shift lens remounted for Nikon. It was very impressive, outclassing the Nikon 28mm shift (a simpler lens).

Maxven said:
The 28-108mm isn't available on anything but FF but apart from that
one lense (which Canon could probably make a 1.6x counterpart to)
from going with the 10D with the choice of hundreds of existing
lenses?

Yeah, they are behind the curve on this one. When Oly launched their autofocus OM-77 (is it really 15 years ago? I feel old...) they had most of the 8 announced AF lenses shipping immediatly, and it didn't take long for Sigma to offer a few more. And the camera could use all the manual focus OM lenses.

Personally, I think the launch would be a lot more successful if they did that again, launch with many more lenses, and include OM compatability. We can only hope.

Maxven said:
I'm no exert on these matters but are you saying that Oly's given
up all the advantages they originally put forth in favour of the
4/3 system?

I'm not saying they've "given up" the advantages, just that they don't seem to be delivering them on this first generation system. I'd be much more impressed if they delivered a small, lightweight weide angle prime or two, and if the camera were a bit smaller. Just my opinion, but there do seem to be a few others who share it. If there's one thing Oly should have learned from OM-AF, it's that if you don't do a good job on the first launch, you may not get a second chance.

Ciao!

Joe

Ciao!

Jukka Jarnberg · Mar 13, 2003

more on

http://pub103.ezboard.com/fthedigitaldinguscommunityfrm43.showMessage?topicID=19.topic

Group Idiot said:
Judging by their press release here:
http://www.four-thirds.com/press_release.htm (at the bottom), it
indeed looks as though their focal lengths ARE based upon a 2X FOV
crop.

Bogus :-(

Brendan
--
If a little knowledge is a dangerous thing, I'm the world's most
dangerous man!
Bunch of new photos at: http://www.pbase.com/bgetchel/root

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Joseph S Wisniewski · Mar 13, 2003

Jukka Jarnberg said:
It would be a crop if the lens would produce image circle for ex
43mm diameter and they'd put masking on to it reduce it to 23mm

But proposed lenses produce image circle approx 23mm and they
utilize it fully then IT IS NOT CROP

GET IT!

The jury is still out on the image circles. I doubt I'll have one on my optic bench befoew the 4'th quarter, but I'll do a full report then.

But consider this, two of the four lenses are known quantities. All 300mm f2.8 lenses produce images circles much larger even than 35mm needs, as does any working geometry for a 50mm macro.

Theres nothing that says a 50-250 wouldn't have that large an image circle, too. The only real wildcard is the 14-52.

Ciao!

Joe

Steven Noyes · Mar 13, 2003

There is a simple relationship in optics called the f-ratio. In camera terms people call it the f-stop and it denotes the speed of the lens. The equation of this term can be calculated by:

f-stop = f-ratio = focal length / aperture

For lenses that are a little larger than standard (about 25% or so. 85mm on 35mm format) the maximum aperture at the diaphragm is the same as the front lens element. On wide angles, it is required to create a larger front lens element when compared to the diaphragm opening because the image circle is so big. But in telephotos, they make a big image circle to start with.

So to respond to your points...

Chris Charlton said:
Steven Noyes said:

True for the wide angle lenses for sure. No need on anything > 50mm.

Click to expand...

Oh so I guess all that light can be thrown away and it will not
effect the speed of the lens? I guess these Olympus designers are
clever the way they bend the laws of physics..

pretty much it. That extra light IS wasted. And no, Olympus engineers are not in line for the Nobel prize for finding a way to use it. Marketing on the other hand

BTW. If you try and take that "wasted" light and push it into the image, all you get is a 200mm or 150mm or 100mm telephoto that is faster. You loose the 300mm.

Chris Charlton said:
By your reasoning if I take a magnifiying glass and project a spot
of the sun on the ground to burn a blade of grass, it makes no
difference if I project a spot 3mm wide or 10mm wide, the light
intensity will be the same amount?
Bending the laws of physics again?

Depends on the size of the magnifying glass. If you take a 100mm lens and create a 10mm circle with it, it will be hotter than a 20mm lens with a 3mm circle. But if you are using the same SIZE magnifying glass, then the 3mm spot will be hotter. BUT, and this is a big BUT, the focal lengths will have to have changed. If the 3mm spot had a lens with a 100m focal length, the 10mm spot has one with 333.33mm. So the 100m lens is faster and brighter.

Optics 101.

Chris Charlton said:
Chris Charlton said:

A 300mm f2.8 is a 300mm f2.8 is a 300mm f2.8. The 4/3 system will
just be sampling a smaller section of the total image area. The
rest of the light goes to waste.

Click to expand...

So all 300mm F2.8 project the same image size as the largest film
available and then the sensor or film samples a smaller section of
it?

YES!!! There are limits to the size of the image circle, but a 300mm lens will make a pretty big circle.

Chris Charlton said:
So you are saying all 300mm F2.8 lenses project an image circle
about 12 inches across (to cover 8X10 film approx) and then they
just sample a 35mm size film crop? or an APS size crop, or a 4/3
size crop?
Complete BS

Sad but no. Optics 101. Have you looked at a 300mm f4 (I don't know of any 300mm F2.8) medium format camera and compared it to a 35mm one. They are pretty much the same size. So the answer is yes to an extent. Up to that standard size lens relationship.

Chris Charlton said:
No it won't be any brighter than a 300mm F2.8 designed for a 35mm
camera, it will be SMALLER....jeez....

No it wont. There might be a small savings on the back elements but the big heavy ones, the ones up front, will be EXACTLY the same size.

Chris Charlton said:
You prove my point perfectly that Olympus will have a hard time
explaining their system to the dumb uneducated masses....

No they won't. The dumb uneducated masses will believe that a 300mm f2.8 will be smaller and lighter.

Chris Charlton said:
Chris Charlton said:

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Click to expand...

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photovoyager · Mar 13, 2003

Joseph S. Wisniewski said:
But consider this, two of the four lenses are known quantities. All
300mm f2.8 lenses produce images circles much larger even than 35mm
needs, as does any working geometry for a 50mm macro.

Exactly... That means that the 4/3 is no more a crop than anything else.

The important part is that these lenses are being designed specifically around a 4/3 sensor, as opposed to 35mm, or medium format, or whatever. Just like the E-10/20 lens is designed around a 2/3 sensor.

Personally I think we should resserve judgement about this until we at least have the specs of the equipment!

Meanwhile I'll probably buy an E-10 or E-20 and enjoy while I watch the interchangeable-lens D-SLR battle played out without the help of my money

.

Regards,
photovoyager

Joseph S Wisniewski · Mar 13, 2003

Jón Ragnarsson said:
Well, I suspect it is the old design, but then again, if you are
making the fastest (and reportedly sharpest) macro in the business,
why mess with the design?

Exactly my point. I have no quibble with any of the Oly technology, just their marketing. Is an advertising campaign like "4/3, a new system for a new century" really any better than "The legend lives!"

Member said:
NOBODY of the big names are making f2
macro.
I guess we will know in June.

J.

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Jon Ragnarsson · Mar 13, 2003

Joseph S. Wisniewski said:
Jón Ragnarsson said:

Well, I suspect it is the old design, but then again, if you are
making the fastest (and reportedly sharpest) macro in the business,
why mess with the design?

Click to expand...

Exactly my point. I have no quibble with any of the Oly technology,
just their marketing. Is an advertising campaign like "4/3, a new
system for a new century" really any better than "The legend lives!"

Well, we all know that marketers live in a different dimension from the rest of us! When the revolution comes....

Joseph S Wisniewski said:
Joseph S Wisniewski said:

NOBODY of the big names are making f2
macro.
I guess we will know in June.

J.

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Click to expand...

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pocoapoco · Mar 13, 2003

I guess I didn't word that post well enough.

Joseph S Wisniewski · Mar 13, 2003

Jón Ragnarsson said:
Well, we all know that marketers live in a different dimension from
the rest of us! When the revolution comes....

I like a man who knows where his towel's at.

Ciao!

Joe

Goldberger · Mar 13, 2003

Steven Noyes said:
There is a simple relationship in optics called the f-ratio. In
camera terms people call it the f-stop and it denotes the speed of
the lens. The equation of this term can be calculated by:

f-stop = f-ratio = focal length / aperture

All this is true. But light comes in different wave lengths (or photons of different energy states, if you want to take that route) which are refracted differently by bits of glass (dispersion, or chromatic abberation). Worse, a spherical surface lens focuses the image of a flat object onto a sphere (a property well known to God, who built hemispherical image sensors for installation in eyeballs), but the sensors (and photographic films and plates) are all flat (spherical abberation). As you correct the image at the image plane by combining different shaped lens elements of different composition glass, you find that the amount of correction needed increases as you increase the image size. That is why a 300 mm f/2.8 MF lens is far bigger and more expensive than a 300 mm f/2.8 35mm lens, even though the aperature and focal length are the same. And that is why 4/3 lenses can be be faster and/or smaller and/or less expensive than the equivalent 35mm camera lens. That Oly slapped a new mount onto an existing optic for the purpose of demonstrating the concept is a non-issue. Why do people try to make it one?

Steven Noyes · Mar 13, 2003

You also believe the DX lines will be smaller and lighter don't you. ONLY on the wide angle, not the Telephotos.

Lets take three 300mm lenses, all three 300mm f/2.8

Lens 1: 2.55Kg, 128mm wide X 252mm long
Lens 2: 2.70Kg, 139mm Wide X 237mm long
Lens 3: 2.60Kg, 122mm Wide X 269mm long

As you can see all of these lenses are the same basic size. Lens 2 is the shortest and is a medium format lens. It is also about 100g heavier and slight larger in diameter. This is not FAR heavier and larger. It is actuall the smallest of the bunch. The size differences have more to do with how the lens design and materials used in the barrel than the fact that one is MF and two are 35mm. Also, the volume of lens 1 (Canon) and 3 (Nikon) is so high, they are highly optimized designs. Also note that the shorter the lens, the wider it is.

You are deluding your self if you think that the 4/3 system will make super light super bright telephoto lenses possible.
.
. Good stuff followed by un-researched guesses.
.

Goldberger said:
make it one?

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Brian Slater · Mar 13, 2003

Steven Noyes said:
You also believe the DX lines will be smaller and lighter don't
you. ONLY on the wide angle, not the Telephotos.

Lets take three 300mm lenses, all three 300mm f/2.8

Lens 1: 2.55Kg, 128mm wide X 252mm long
Lens 2: 2.70Kg, 139mm Wide X 237mm long
Lens 3: 2.60Kg, 122mm Wide X 269mm long

As you can see all of these lenses are the same basic size. Lens 2
is the shortest and is a medium format lens. It is also about 100g
heavier and slight larger in diameter. This is not FAR heavier and
larger. It is actuall the smallest of the bunch. The size
differences have more to do with how the lens design and materials
used in the barrel than the fact that one is MF and two are 35mm.
Also, the volume of lens 1 (Canon) and 3 (Nikon) is so high, they
are highly optimized designs. Also note that the shorter the lens,
the wider it is.

This argument is not totally convincing. I'm not sure which medium format lens you are discussing. And since neither Nikon nor Canon make such a lens I wonder if your aren't comparing different fruit. How about the difference between two lenses form the same manufacturer. Carl Zeiss make such a pair:

35 mm (Contax) 2.73 kg 120mm Wide X 244mm Long
MF (Hasselblad) 3.8 kg 138mm Wide X 277mm Long

These are not insignificant differences. Also, note that the width is maximized at the entrance pupil, so that the lens for smaller format (smaller image circle) can be slimmer over a considerable portion of its length, hence the weight savings. These weight savings are obviously most important for long tele lenses used for example in nature photography, where what you carry on your back may break it. I do expect that the new 4/3 300mm will weigh less than a typical opric built for 35 mm coverage.

Steven Noyes said:
You are deluding your self if you think that the 4/3 system will
make super light super bright telephoto lenses possible.

But I'd much rather carry (and perhaps pay for) an Olympus 4/3 with its 300mm f2.8, than a Nikon F100 with a 400 f2.8! (Assuming similar pixel count).

Brian

Steven Noyes said:
.
. Good stuff followed by un-researched guesses.
.

Steven Noyes said:

make it one?

Click to expand...

--
---
Something different.
http://www.pbase.com/snoyes/the_homeland

Steven Noyes · Mar 13, 2003

but you can't make them see.

1) Yes Canon makes a 300mm f2.8
2) Yes Mamiya makes a 300mm f2.8
3) Yes Nikon makes a 300mm f2.8

Brian Slater said:
Brian Slater said:

Lens 1: 2.55Kg, 128mm wide X 252mm long
Lens 2: 2.70Kg, 139mm Wide X 237mm long
Lens 3: 2.60Kg, 122mm Wide X 269mm long

Click to expand...

35 mm (Contax) 2.73 kg 120mm Wide X 244mm Long
MF (Hasselblad) 3.8 kg 138mm Wide X 277mm Long

And yes the heaviest 35mm 300 f/2.8 is heavier than the lightest MF!
And yes the shortest of these 5 300mm f2.8 lenses is a MF!

645 has a much larger image circle than 35mm. But you would not know it from the lens sizes. WHY??? IT DOES NOT MATER THAT MUCH!!!

The differences have more to do with optimizations (Nikon and Canon make 10's more of these lenses than the others), design preferences and materials than the image circle.

Steven

Brian Slater said:
Steven Noyes said:

You also believe the DX lines will be smaller and lighter don't
you. ONLY on the wide angle, not the Telephotos.

Lets take three 300mm lenses, all three 300mm f/2.8

Lens 1: 2.55Kg, 128mm wide X 252mm long
Lens 2: 2.70Kg, 139mm Wide X 237mm long
Lens 3: 2.60Kg, 122mm Wide X 269mm long

As you can see all of these lenses are the same basic size. Lens 2
is the shortest and is a medium format lens. It is also about 100g
heavier and slight larger in diameter. This is not FAR heavier and
larger. It is actuall the smallest of the bunch. The size
differences have more to do with how the lens design and materials
used in the barrel than the fact that one is MF and two are 35mm.
Also, the volume of lens 1 (Canon) and 3 (Nikon) is so high, they
are highly optimized designs. Also note that the shorter the lens,
the wider it is.

Click to expand...

This argument is not totally convincing. I'm not sure which medium
format lens you are discussing. And since neither Nikon nor Canon
make such a lens I wonder if your aren't comparing different fruit.
How about the difference between two lenses form the same
manufacturer. Carl Zeiss make such a pair:

35 mm (Contax) 2.73 kg 120mm Wide X 244mm Long
MF (Hasselblad) 3.8 kg 138mm Wide X 277mm Long

These are not insignificant differences. Also, note that the width
is maximized at the entrance pupil, so that the lens for smaller
format (smaller image circle) can be slimmer over a considerable
portion of its length, hence the weight savings. These weight
savings are obviously most important for long tele lenses used for
example in nature photography, where what you carry on your back
may break it. I do expect that the new 4/3 300mm will weigh less
than a typical opric built for 35 mm coverage.

I don't. It will measured in grams, and might actually be heavier.

Brian Slater said:
Brian Slater said:

You are deluding your self if you think that the 4/3 system will
make super light super bright telephoto lenses possible.

Click to expand...

But I'd much rather carry (and perhaps pay for) an Olympus 4/3 with
its 300mm f2.8, than a Nikon F100 with a 400 f2.8! (Assuming
similar pixel count).

That is a different issue. And I agree with you there. But don't expect magic lenses that are smaller because of the image circle.

Brian Slater said:
Brian

Brian Slater said:

.
. Good stuff followed by un-researched guesses.
.

Brian Slater said:

make it one?

Click to expand...

--
---
Something different.
http://www.pbase.com/snoyes/the_homeland

Click to expand...

--
---
Something different.
http://www.pbase.com/snoyes/in_the_supers

Looks like 4/3 *IS* a "Crop"

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Jon Ragnarsson

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Looks like 4/3 IS a "Crop"