dpreview also tries to teach the trolls about ISO/aperture :)

On 9/10/2017 3:27 AM, Sandman wrote:
In article , PeterN wrote:

snip

Sandman:
Furthermore, EV+5 on one camera is NOT the same as EV+5 on another
camera, like ISO is trying to be.

Because adaptation of methods of exposure varies, ISO should not be
considered an absolute measurement of sensitivity, but merely a
reasonable guideline. That is one of the reasons a lot of us bracket
exposures.

But the point is, ISO *was* an absolute measurement of sensitivity, meaning
that one film of ISO400 and another film of ISO400 was equally sensitive to
light, that was the entire point of ISO.

Now, when digital rolled around, they adopted ISO to mean sensor
amplification, but the problem was that ISO is sensitivity over a unit area,
not over the exposed area (since that was pretty much the same back in 135
days), but digital cameras can't use a standard that is relevant to unit
areas when each camera had different amount of such unit areas


And there WAS a item I could do a six minute mile. We are discussion
what is, reality, and how to make the best use of it,

--
PeterN

On 10 Sep 2017 09:43:33 GMT, Sandman wrote:

In article , Eric Stevens wrote:

PeterN:
Because adaptation of methods of exposure varies, ISO should not
be considered an absolute measurement of sensitivity, but merely
a reasonable guideline. That is one of the reasons a lot of us
bracket exposures.

Sandman:
But the point is, ISO *was* an absolute measurement of
sensitivity, meaning that one film of ISO400 and another film of
ISO400 was equally sensitive to light, that was the entire point
of ISO.

Now, when digital rolled around, they adopted ISO to mean sensor
amplification, but the problem was that ISO is sensitivity over a
unit area, not over the exposed area (since that was pretty much
the same back in 135 days), but digital cameras can't use a
standard that is relevant to unit areas when each camera had
different amount of such unit areas

They can, when what matters is not the total amount of light falling
on the entire sensor but the amount of light which falls on a unit
area of sensor.

Incorrect on several accounts. First, the amount of light that falls on a
unit area is never "the matter" to the photographer. The end result is.

The photographer has no ability to assess the end result until after
the exposure is made. He has no role in determining the ISO
sensitivity.

Secondly, when you have different amount of unit areas in play, whatever
"iso" one unit area may or may not be in relation to is irrelevant.

Would you care to rewrite that? I can't understand what you are trying
to say.

Thirdly, ISO for digital cameras does NOT means X amount of light gathered
per unit area, that's the *film* usage of ISO. "ISO" for digital cameras is
an arbitrary value to match the *lightness* of the film-equivalent of that
ISO setting.

For the full definition of ISO you need to read the specification ISO
12232:2006. Unfortunately that is pay-walled but the next best thing
is
https://en.wikipedia.org/wiki/Film_s...:2006_standard

So when you talk about "ISO" in digital cameras, it has absolutely nothing to
do with light per unit area other than the camera trying to emulate the
result of a ISO analog film. Which, depending on your sensors size means you
have to amplify it more or less than another camera.

Emulation of analog film has nothing to do with it.

Those pixels in the unit area don't care what is happening in the
neighbouring unit area. All that matters to them is the amount of
light which falls upon them.

They are also not more "sensitive" depending on your ISO settings. They are
fixed. With less total light, the signal needs to be amplified more to match
the brightness of the film ISO emulation step.

Agreed.
--

Regards,

Eric Stevens

On 10 Sep 2017 09:45:57 GMT, Sandman wrote:

In article , Eric Stevens wrote:

Eric Stevens:
Same logical errors.

Sandman:
Same hot air from the trolls of rpd

I could explain it but it requires diagrams which I can't put on rpd
and it requires algebra which is too complicated to be published in
a text news group. One day I might produce it as a PDF, but it's
quite a lot of work.

Like I said - more hot air from the trolls. :-D

And it's also ironic that Eric, in a photography usenet group, seem to want
to claim there is no way to convey something other than text here :-D

Please read my words again. RPD is a text-only news group. If I want
to explain things properly I *have* to use diagrams and mathematical
symbols.
--

Regards,

Eric Stevens

In article , Eric Stevens
wrote:


Eric Stevens:
Same logical errors.

Sandman:
Same hot air from the trolls of rpd

I could explain it but it requires diagrams which I can't put on rpd
and it requires algebra which is too complicated to be published in
a text news group. One day I might produce it as a PDF, but it's
quite a lot of work.

Like I said - more hot air from the trolls. :-D

And it's also ironic that Eric, in a photography usenet group, seem to want
to claim there is no way to convey something other than text here :-D

Please read my words again. RPD is a text-only news group. If I want
to explain things properly I *have* to use diagrams and mathematical
symbols.

that explains why posts don't include links to photos.

oh wait...

On Sep 10, 2017, nospam wrote
(in ) :

In , Eric Stevens
wrote:

Eric Stevens:
Same logical errors.

Sandman:
Same hot air from the trolls of rpd

I could explain it but it requires diagrams which I can't put on rpd
and it requires algebra which is too complicated to be published in
a text news group. One day I might produce it as a PDF, but it's
quite a lot of work.

Like I said - more hot air from the trolls. :-D

And it's also ironic that Eric, in a photography usenet group, seem to want
to claim there is no way to convey something other than text here :-D

Please read my words again. RPD is a text-only news group. If I want
to explain things properly I *have* to use diagrams and mathematical
symbols.

that explains why posts don't include links to photos.

oh wait...

I guess you better wait, seeing as it is your posts which never include links
to photos.
Your photos anyway.

--

Regards,
Savageduck

In article .com,
Savageduck wrote:

And it's also ironic that Eric, in a photography usenet group, seem to
want
to claim there is no way to convey something other than text here :-D

Please read my words again. RPD is a text-only news group. If I want
to explain things properly I *have* to use diagrams and mathematical
symbols.

that explains why posts don't include links to photos.

oh wait...

I guess you better wait, seeing as it is your posts which never include links
to photos.
Your photos anyway.

according to eric, it's a text only group and that would be against the
rules.

In article , Eric Stevens wrote:

snip

Eric Stevens:
Those pixels in the unit area don't care what is happening in
the neighbouring unit area. All that matters to them is the
amount of light which falls upon them.

Sandman:
They are also not more "sensitive" depending on your ISO settings.
They are fixed. With less total light, the signal needs to be
amplified more to match the brightness of the film ISO emulation
step.

Agreed.

Finally

--
Sandman

In article , Eric Stevens wrote:

Eric Stevens:
Same logical errors.

Sandman:
Same hot air from the trolls of rpd

Eric Stevens:
I could explain it but it requires diagrams which I can't put on
rpd and it requires algebra which is too complicated to be
published in a text news group. One day I might produce it as a
PDF, but it's quite a lot of work.

Sandman:
Like I said - more hot air from the trolls. :-D

And it's also ironic that Eric, in a photography usenet group,
seem to want to claim there is no way to convey something other
than text here :-D

Please read my words again. RPD is a text-only news group.

Yes, rec.PHOTO.digital is text-only, which has been a problem for all the
photographers here that hasn't managed to find a way to share their
photographies in any way, shape or form. We're all stuck trying to describe
our photos using words to get feedback. :-D

--
Sandman

In article ,
Sandman wrote:

In article , Eric Stevens wrote:

Eric Stevens:
Same logical errors.

Sandman:
Same hot air from the trolls of rpd

Eric Stevens:
I could explain it but it requires diagrams which I can't put on
rpd and it requires algebra which is too complicated to be
published in a text news group. One day I might produce it as a
PDF, but it's quite a lot of work.

Sandman:
Like I said - more hot air from the trolls. :-D

And it's also ironic that Eric, in a photography usenet group,
seem to want to claim there is no way to convey something other
than text here :-D

Please read my words again. RPD is a text-only news group.

Yes, rec.PHOTO.digital is text-only, which has been a problem for all the
photographers here that hasn't managed to find a way to share their
photographies in any way, shape or form. We're all stuck trying to describe
our photos using words to get feedback. :-D

The USENET and r.p.d are for discution. If you wanna show your pictures
and don't have an online site:

https://www.flickr.com/

I have rolled my own:

http://tinyurl.com/oxhflsw
--
teleportation kills

On 11 Sep 2017 05:34:13 GMT, Sandman wrote:

In article , Eric Stevens wrote:

snip

Eric Stevens:
Those pixels in the unit area don't care what is happening in
the neighbouring unit area. All that matters to them is the
amount of light which falls upon them.

Sandman:
They are also not more "sensitive" depending on your ISO settings.
They are fixed. With less total light, the signal needs to be
amplified more to match the brightness of the film ISO emulation
step.

Agreed.

Finally

No, not finally. Not at all while you twist words the way you have in
your reply.

Honesty is the best policy. Yours isn't even the next best.
--

Regards,

Eric Stevens