prosumer future

lid wrote:

It's exactly the same as trying to put two gallons
into a one gallon bucket. Is it correct to say that, for a brief
moment, the one gallon bucket held two gallons, just before it
overflowed?

No, it's exactly different. The whole idea of the one gallon "bucket" is that you
don't want more than one gallon of data, and to have detail that bucket has to have a
different amount in it than other nearby buckets, which means they can't all be full
or you're missing data even though none of them actually overflowed.


Effectively, you'd be doing multiple exposures and summing them later.

No, I'm suggesting that the data from a single exposure might be captured at various
points during the exposure. That would essentially yield the same data you would get
from multiple exposures (though it wouldn't require as much memory), but wouldn't
require that the scene remain static through multiple exposures. Perhaps it's merely
semantics, but I don't see that as summing multiple exposures, though the final
result may be the same. In the final image you'd use the data from the end (or near
the end) of the exposure for the darkest areas and for the lightest you'd use the
data from the point at which those areas became completely saturated. Everything in
between would be based on the data from points within that range, effectively
reducing the contrast such that you could capture both shadow and highlight detail.


This is a perfectly reasonable way of extending dynamic range. You
can do it already, albeit rather slowly.

If it's possible to capture multiple data points from a single exposure it could be
as fast as other relatively simple corrections.


--
Steve

The above can be construed as personal opinion in the absence of a reasonable
belief that it was intended as a statement of fact.

If you want a reply to reach me, remove the SPAMTRAP from the address.

In article ,
David Gay wrote:

Matt Ion writes:
Okay... how many photographers can you think of, besides maybe yourself,
who give the above choice, and *having the means to afford the 1D*, would
turn it down because it was too big or too heavy?

Myself, obviously. But haven't you noticed the regular posts about hiking
and weight which surface around here? Or the people saying they prefer
the point-&-shoots for weight reasons?

Wusses! Planning to go on a hike in Snowdonia in the next few weeks, on
which I shall be taking my newly acquired MPP large format technical camera.
The camera weighs 3 kilograms, the tripod it sits on (required) weighs 2.
That's a minimum shooting weight of 5 kilos, before one takes into account
the 10D which will be used as a fancy light meter, for maing sure I have the
exposure right before I waste a sheet of film (costs 3UK pounds to trip the
shutter on that camera).

"Chris Brown" wrote:

That's a minimum shooting weight of 5 kilos, before one takes into account
the 10D which will be used as a fancy light meter, for maing sure I have
the
exposure right before I waste a sheet of film (costs 3UK pounds to trip
the
shutter on that camera).

You'll need a _long_ telephoto to get reasonable spot readings. You'd be
better of with a Sony F707.

David J. Littleboy
Tokyo, Japan

In article ,
David J. Littleboy wrote:

"Chris Brown" wrote:

That's a minimum shooting weight of 5 kilos, before one takes into account
the 10D which will be used as a fancy light meter, for maing sure I have
the
exposure right before I waste a sheet of film (costs 3UK pounds to trip
the
shutter on that camera).

You'll need a _long_ telephoto to get reasonable spot readings. You'd be
better of with a Sony F707.

It's for full previews rather than spot metering. I've got a real spot meter
for that.

Steve wrote:


lid wrote:

It's exactly the same as trying to put two gallons into a one
gallon bucket. Is it correct to say that, for a brief moment, the
one gallon bucket held two gallons, just before it overflowed?

No, it's exactly different. The whole idea of the one gallon
"bucket" is that you don't want more than one gallon of data, and to
have detail that bucket has to have a different amount in it than
other nearby buckets, which means they can't all be full or you're
missing data even though none of them actually overflowed.

Right.

Effectively, you'd be doing multiple exposures and summing them later.

No, I'm suggesting that the data from a single exposure might be
captured at various points during the exposure. That would
essentially yield the same data you would get from multiple
exposures (though it wouldn't require as much memory), but wouldn't
require that the scene remain static through multiple
exposures. Perhaps it's merely semantics, but I don't see that as
summing multiple exposures, though the final result may be the
same.

OK. Effectively, it's the same thing. :-)

In the final image you'd use the data from the end (or near
the end) of the exposure for the darkest areas and for the lightest
you'd use the data from the point at which those areas became
completely saturated.

What you're asking for is to read the charge in the electron well
without disturbing it.

Andrew.

lid wrote:

What you're asking for is to read the charge in the electron well
without disturbing it.

Isn't that what I said in the first post?

Reflecting a bit further, I wonder if the only thing necessary for many situations
might be simply to know at what point during an exposure any given pixel reaches
saturation. If the light level changed during the exposure, as it would with strobe
use, things would get more complicated, but for many (most?) situations the
accumulation of light will be a linear function of time. That would essentially
provide the extra data that is lost by overfilling the bucket, allowing for an
automated adjustment that would be a function of how much each bucket was filled or
overfilled.


--
Steve

The above can be construed as personal opinion in the absence of a reasonable
belief that it was intended as a statement of fact.

If you want a reply to reach me, remove the SPAMTRAP from the address.