«

On 5/02/2011 10:53 a.m., Wally wrote:
> On Fri, 4 Feb 2011 09:38:54 -0800, C J Campbell
> <> wrote:
>
>> On 2011-01-31 23:06:26 -0800, Wally said:
>>
>>> The Canon 7D with its 1.6-factor sensor weighs 900 g with battery --
>>> the Full Frame Canon 5D2 weighs 907 g.
>>>
>>> What the hell?
>>>
>>> Why aren't the smaller-frame bodies significantly smaller than the
>>> bigger frame models, as used to be the case between 35mm film cameras
>>> and the medium format models like the RZ and the Hasselblad?
>>
>> It is far worse than that. Why are full-frame cameras so much heavier
>> than their predecessors? Why does a Nikon FM2 weigh 540g, while a D3x
>> weighs 1220g? The D3x does not even need the stuff for handling film!
>> Yet, despite all this additional weight, the pentaprism does not
>> transmit light to the viewfinder as well as the FM2 and overall
>> performance is arguably no better. Even a D700 weighs 995g. What on
>> earth for?
>
> Maybe the manufacturers pour cement into them to give them extra heft.
> Makes them feel more expensive and justifies the high price.
>
No point comparing a D3x with an FM. Better comparison may be an F3
with MD4, which with a set of batteries in the MD4 probably weighs more
than a D3x.
The "less bright" VF relates to semi-silvered mirror in phase-detect AF
dslrs, there's a secondary mirror behind the main mirror that reflects
image down to the AF unit in the bottom of the mirror box. The CAM 3500
unit in the D3/700/300 series is hefty, with a very large lens. Less
capable AF systems (low light/number of AF points) are also much
smaller. That's probably why a D700 weighs more than a Canon 5DII, and
why in comparison, the 5DII AF performance is lousy.
Sure - they could probably make a "digital FM" (or IMO, a "digital FA"
would be better with PASM metering modes). Some people have been
whining about this for years, and so far none of the makers have come up
with one.

Alfred Molon <> wrote:
> Ray Fischer
>> Wally <> wrote:
>> >The Canon 7D with its 1.6-factor sensor weighs 900 g with battery --
>> >the Full Frame Canon 5D2 weighs 907 g.
>> >
>> >What the hell?
>>
>> "If a sensor weighs just three grams then why does the
>> camera weigh 900 grams?"
>>
>> A sensor is not a camera.
>> A camera is not a sensor.
>>
>> Get a clue.
>
>Still there are film cameras whose size is a fraction of the size of
>current full frame DSLRs.

So what?

> It should not be a problem to make very
>compact full frame DSLRs.

I am never impressed by ignorant fools who think that even though they
have no experience or training, they still believe themselves to be
smarter than engineers with gradaute degrees and decades of experience
designing cameras.

Know anybody like that?

--
Ray Fischer | Mendacracy (n.) government by lying
| The new GOP ideal

On 5/02/2011 1:32 p.m., Paul Furman wrote:
> Me wrote:
>> On 5/02/2011 10:53 a.m., Wally wrote:
>>> On Fri, 4 Feb 2011 09:38:54 -0800, C J Campbell
>>> <> wrote:
>>>
>>>> On 2011-01-31 23:06:26 -0800, Wally said:
>>>>
>>>>> The Canon 7D with its 1.6-factor sensor weighs 900 g with battery --
>>>>> the Full Frame Canon 5D2 weighs 907 g.
>>>>>
>>>>> What the hell?
>>>>>
>>>>> Why aren't the smaller-frame bodies significantly smaller than the
>>>>> bigger frame models, as used to be the case between 35mm film cameras
>>>>> and the medium format models like the RZ and the Hasselblad?
>>>>
>>>> It is far worse than that. Why are full-frame cameras so much heavier
>>>> than their predecessors? Why does a Nikon FM2 weigh 540g, while a D3x
>>>> weighs 1220g? The D3x does not even need the stuff for handling film!
>>>> Yet, despite all this additional weight, the pentaprism does not
>>>> transmit light to the viewfinder as well as the FM2 and overall
>>>> performance is arguably no better. Even a D700 weighs 995g. What on
>>>> earth for?
>>>
>>> Maybe the manufacturers pour cement into them to give them extra heft.
>>> Makes them feel more expensive and justifies the high price.
>>>
>> No point comparing a D3x with an FM. Better comparison may be an F3 with
>> MD4, which with a set of batteries in the MD4 probably weighs more than
>> a D3x.
>> The "less bright" VF relates to semi-silvered mirror in phase-detect AF
>> dslrs, there's a secondary mirror behind the main mirror that reflects
>> image down to the AF unit in the bottom of the mirror box. The CAM 3500
>> unit in the D3/700/300 series is hefty, with a very large lens. Less
>> capable AF systems (low light/number of AF points) are also much
>> smaller. That's probably why a D700 weighs more than a Canon 5DII, and
>> why in comparison, the 5DII AF performance is lousy.
>> Sure - they could probably make a "digital FM" (or IMO, a "digital FA"
>> would be better with PASM metering modes). Some people have been whining
>> about this for years, and so far none of the makers have come up with
>> one.
>
> Thanks for the better explanation. AF sensor (and AF motor). Where does
> the metering system go?

I don't know. Nikon introduced matrix metering with the FA model -
before AF, even the F3AF. I think (but don't know) that metering must
be with photosensors in the prism assembly, small enough and out of the
focal plane enough so they can't be seen though the VF, and there's
enough of them so that each focus point can be user selected as metering
point for centre-weighted or spot, and approx spot diameter can be user
selected on many models. That's 51 AF points /and/ 51 CW centre or spot
points on D3/700/300 models. I've never seen documentation or stripped
down a camera enough to see what really goes on. If someone knows, it
would be interesting to see how it really works. But it works well, I
had an FA, and the earliest matrix metering system worked really well
most of the time. That also had spot and CW, but limited to the centre
point.
>
> The thing is; if you eliminated all that automation, it would be a
> pro-only camera, and many 'pro's' want high performance AF and other
> features for sports and wildlife so it really would only be useful for
> street shooting and certain kinds of photojournalism - a rather narrow
> market. Pro's who do the slow measured tripod type shooting would mostly
> not benefit from compactness, except backpackers and photo enthusiast
> tourists I guess. For the relevant segment, the new Leica is probably
> about right. If it were small and inexpensive with only manual
> functions, it would be great for students and enthusiasts with modest
> means but there's no money in that market. The closest match for that
> market is probably Russian medum format film cameras but no such thing
> for digital exists. If the world economy collapses for decades and
> everyone is poor with more time to learn how to shoot manual, we might
> see such a camera emerge. If you don't need super image quality or
> dynamic range, smaller formats are fine.
Yes - the Leica is in the boutique market. Breaking in to that market
without a "name" and heritage isn't likely to happen. The major SLR
makers could do it. It's a marketing issue - not a technical issue.

On Feb 4, 7:03*am, Alfred Molon <alfred_mo...@yahoo.com> wrote:
> In article <4d4b9cfc$0$10545$742ec...@news.sonic.net>, Ray Fischer
> says...
>
> > Wally *<Wa...@luxx.com> wrote:
> > >The Canon 7D with its 1.6-factor sensor weighs 900 g with battery --
> > >the Full Frame Canon 5D2 weighs 907 g.
>
> > >What the hell?
>
> > "If a sensor weighs just three grams then why does the
> > camera weigh 900 grams?"
>
> > A sensor is not a camera.
> > A camera is not a sensor.
>
> > Get a clue.
>
> Still there are film cameras whose size is a fraction of the size of
> current full frame DSLRs. It should not be a problem to make very
> compact full frame DSLRs. The electronics can't take so much space, as
> the Sony NEX cameras demonstrate it.

True, but look at the end result. That camera looks ridiculous with a
long lens on it.
And the controls are harder to use.

DanP

On 5/02/2011 10:03 p.m., Eric Stevens wrote:

>
> I thought the film Nikon cameras made use of light reflected off the
> film.
>
For TTL flash metering, I think also introduced with the FA, then later
FE2/FM2 models - can't remember if the F3 had it. There was a separate
small photosensor, recessed in the base of the mirror box, pointing
toward the film. It seemed to work okay, but not even remotely close to
as well as how current flash systems perform.
Continued through to digital IIRC with the D100 (and D1?), when it
became evident that with the complex reflectivity from sensors, it
didn't work very well - worse than it did with film, so replaced with
"iTTL" using pre-flashes for TTL metering on later models.

On 2/5/2011 4:03 AM, Eric Stevens wrote:

> I thought the film Nikon cameras made use of light reflected off the
> film.

Nikon used "off the film" metering for TTL flash, and in a very few
models (IIRC the FA, FG, and N2000) to do a final adjustment to
metering tp compensate for non AI-s lenses in Program and/or Shutter
priority modes. I don't believe it was ever used as the main metering
approach.

--
Mike Benveniste -- (Clarification Required)
You don't have to sort of enhance reality. There is nothing
stranger than truth. -- Annie Leibovitz

Alfred Molon <> wrote:
> Go ahead and keep talking nonsense. The reality is that compact cameras
> dominate the market. Size matters.

Cell phone cameras dominate. Everyone has one or three.
Many people don't have a compact camera.

Of course, for sunshine shots your average compact or phone camera
does very well, and good ones are excellent. Indoors most need
flash already during the day.


BTW, utilizing a huge dewar flask full of liquid nitrogen
and a tripod you *can* make available light portraits with
compact cameras. Even on a summer's night outside, where just
a small campfire or a single candle adds light to a moonless,
overcast night. You'll still need some effective noise and hot
pixel supression for your compact camera. Maybe even dark frames
to combat thermal glow.

Been there, done just that. With a big camera, sometimes using
a big lens, handheld, and without the participants being frozen
to death. And it's much more portable and long term storable
than the liquid nitrogen.

Yes, if you know what you are doing --- which may mean multiple
flash units placed and balanced just right and a willing subject
with time and tolerance (and the ability to act) --- you can pull
off flash shots that look natural and spontaneous. But most
compact cameras can't even adjust flash power, much less tilt
and swivel the head. A few cameras have at least a hot shoe,
but even if the owners have flash unit(s) they usually don't
carry them casually like cameras.


All of which means that I'll keep my big camera and use it whenever
there's something special. Especially as I carry 'casual' cameras
(plural by now) and know what they cannot do.

-Wolfgang

Paul Furman <paul-@-edgehill.net> wrote:
> George Kerby wrote:
>> Alfred Molon wrote:

>>> Still there are film cameras whose size is a fraction of the size of
>>> current full frame DSLRs.

>> They still make film for the Minox?

They still make film. You can probably have it cut into
smaller sizes.

> Nikon FE is an example of a small FX film camera, or Olympus (forget the
> model). For digital, I think the AF system requires quite a bit of space
> at the side(s?) of the mirror box,

Forget AF. Use a fixed focus. Or maybe throw in a switch
'portrait/landscape'.
Forget viewfinders, use a tiny, not parallax corrected tunnel
viewer.

> the rear LCD adds thickness on top of
> the sensor

Forget the LCD (and save battery power). 35mm film had no
LCD either.

> and even the sensor is thicker than film.

But not much, and you don't need film spools.

> The batteries are
> big and heavy,

but can be shaped arbitrarily as an inbuilt LiPo battery.
(Maybe fill one of the no-longer-needed film spools except for
the card slot. That should give you plenty power.)

Or use a standard round cell and live with the limited power
it gives you --- after all, you never will want more than 24 or
36 images. Film didn't manage more either.

> the flash is bulky...

I've seen tiny inbuild flash on one-time use 35mm film cameras,
so it doesn't need to be bulky. (It won't be powerful, either,
just enough to light a portrait at 1 or 1.5 meters.)

> if you were willing to forego all
> that, it should be possible. Mirrorless APS is probably the closest
> thing today, or micro 4/3 if you don't need a real viewfinder or high
> ISO performance.

Keep the 24x36mm sensor, just cut away all the fluff, see
above. Have it use a microSD, they are tiny, can store lots
and can be exchanged by the user.

Then you'll have the tinyest, most impotent full frame camera.
(Think: small plastic one time use film camera for <$10 with
development, but in digital). Noone will buy one as it'll be *way*
to expensive, as the sensor can't be miniaturized for cost savings.

And remember, the modern compact cameras are larger than the small
models of their earlier bretheren: the screen already takes all
of the rear and cannot be shrunk, either.

-Wolfgang

Mike Benveniste <> wrote:

> Nikon used "off the film" metering for TTL flash, and in a very few
> models (IIRC the FA, FG, and N2000) to do a final adjustment to
> metering tp compensate for non AI-s lenses in Program and/or Shutter
> priority modes. I don't believe it was ever used as the main metering
> approach.

I seem to remember reading about some rangefinder camera using the
reflection of a white painted leaf in the middle of the shutter
curtain for metering ...

-Wolfgang

In article <olsg28->,
Wolfgang Weisselberg <> wrote:

> Mike Benveniste <> wrote:
>
> > Nikon used "off the film" metering for TTL flash, and in a very few
> > models (IIRC the FA, FG, and N2000) to do a final adjustment to
> > metering tp compensate for non AI-s lenses in Program and/or Shutter
> > priority modes. I don't believe it was ever used as the main metering
> > approach.
>
> I seem to remember reading about some rangefinder camera using the
> reflection of a white painted leaf in the middle of the shutter
> curtain for metering ...
>
> -Wolfgang

The Leica M6, M7, and MP film rangefinders use this method of metering.
I don't know how the M8.x and M9 work their metering because I've never
used them.

Metering off the shutter curtain was developed after the M5, the first
Leica "M" with an integral meter flopped -- besides the fact that the M5
was significantly larger than the M4 which preceded it, its meter cell
was on a swinging arm that occupied the space between the lens's rear
element and the film plane. This didn't work for lenses with extensive
back focus, such as the 21mm f/3.4 or f/4, which would routinely break
the meter cell arm off, or at least prevent it from swinging into place.
(The modern 21mm f/2.8 doesn't extend nearly as far toward the film
plane.)

Modern M6 et seq. place the SBC meter sensor out of the way diagonally
from the entire imaging volume between the flange and film.

Additionally, all Leica lenses are sold with a leather pouch which has a
50% gray circle printed on the bottom so you don't have to carry a gray
card.

M6 Metering circle:
<http://www.mir.com.my/rb/photography...-M6/images/lei
ca-M6blk-F.jpg>

Same, close-up (SBC sensor hidden behind baffle, upper left):
<http://static.photo.net/attachments/bboard/00W/00Wtno-261671584.JPG>

Leica 21mm f/4 showing the extreme rear element length:
<http://www.kenrockwell.com/leica/images/21mm-f4/D3S_5805-1200.jpg>