Exposure and How It Works - A Beginner's Guide - Part 1 (Page 17): Some say point at the light source, others say point at the camera and some even suggest half way in between. But...

selmslie Loc: Fernandina Beach, FL, USA

srt101fan wrote:

Is this a case where both of you could be right? I think the terminology and wording gets in the way of clarity.

You see articles on the use of incident light meters that say you point the meter at the light source. It's not much of a jump to infer from that that you are measuring the light from the source....as it falls on the subject!? 😊

Some say point at the light source, others say point at the camera and some even suggest half way in between.

But since digital highlights are critical, pointing at the light source is probably the safest choice. Shadows are easy to recover.

Bipod

Exposure is a plane.

If aperture and shutter speed are expressed as base2 logs and prolotted on an graph, X = shutter and Y = aperture,
then each EV is a line with a slope of -1 (for a fixed ISO, say ISO 100). For example, the camera setting for EV 15
is a line, each point on which is a combination of shutter and aperture that gives a "normal" exosure for a meter reading
of EV 15.

If ISO speed is added as the Z dimension, then each EV number is a plane. For example, the camera settings for
EV 15 are a plane, each point on which represents a combiantion of shutter, aperture and ISO that gives a "normal"
exposure for EV 15.

I'm not saying anybody is wrong, or their calculator is wrong, or their technique is wrong, I'm just trying to find the
clearest and simplest way to think about exposure.

"Triangle" is not it. "Triad" is closer -- but the exposure triad graphs as a plane, not a triangle.

And the simplest way I know to think about exposure is as a simple arthmetic equation:

TimeValue + ApertureValue = BrightnessValue + SpeedValue

therefore,

BrightnessValue = TimeValue + ApertureValue - SpeedValue

If all four values are expressed as base2 logarithms, this math works. The members of the ASA/ISO committee
that made APEX an ASA/ISO standard--including optical engineers and sensiometrists--knew what they were doing.

BebuLamar

selmslie wrote:

Some say point at the light source, others say point at the camera and some even suggest half way in between.

But since digital highlights are critical, pointing at the light source is probably the safest choice. Shadows are easy to recover.

I point it toward the camera.

selmslie Loc: Fernandina Beach, FL, USA

BebuLamar wrote:

I point it toward the camera.

That’s how I do it for film because it’s hard to blow film highlights.

AndyH Loc: Massachusetts and New Hampshire

selmslie wrote:

That’s how I do it for film because it’s hard to blow film highlights.

I’ve done this since my incident meter was a Norwood Director.

AA told me to.

Andy

tdekany Loc: Oregon

Bipod wrote:

Believe whatever you want, tdekany, but stop distorting the words of other posters.
And you might try citing sources or presenting arguments or evidence.

I’m sure that we could print LF files large enough to make them look fuzzy and pixelated. Is that mean that we shouldn’t use LF cameras?

selmslie Loc: Fernandina Beach, FL, USA

tdekany wrote:

I’m sure that we could print LF files large enough to make them look fuzzy and pixelated. Is that mean that we shouldn’t use LF cameras?

Take a look at Clyde Butcher's huge prints. You can stand very close to them and they remain very sharp.

But stuff you take with your tiny smart phone sensor will look sharp if you display it on a 2k or 4k computer monitor.

It's not a question of sharp or blurry. It's a question of sharper or blurrier.

Give it up. You lost this argument a long time ago.

tdekany Loc: Oregon

selmslie wrote:

Take a look at Clyde Butcher's huge prints. You can stand very close to them and they remain very sharp.

But stuff you take with your tiny smart phone sensor will look sharp if you display it on a 2k or 4k computer monitor.

It's not a question of sharp or blurry. It's a question of sharper or blurrier.

Give it up. You lost this argument a long time ago.

Are you saying that you believe the nonsense that a FF camera can’t print 36x24? Or larger that retains sharpness? You seem to like to argue for the sake of argument.

Btw, I’ll put my 64mp hi res shots from my EM5 Mark2 against your A7 or D610.

tdekany Loc: Oregon

Quote:

There is nothing worse than a sharp image of a fuzzy concept

I’m sure AA and photographers like him would remind you of the above after looking at your and Bipod’s work. Both of you should put more effort into THAT part of photography. Just saying.

selmslie Loc: Fernandina Beach, FL, USA

tdekany wrote:

Are you saying that you believe the nonsense that a FF camera can’t print 36x24? Or larger that retains sharpness? You seem to like to argue for the sake of argument.

Btw, I’ll put my 64mp hi res shots from my EM5 Mark2 against your A7 or D610.

You would lose. Take a look at Photographic System Resolution and you might understand why.

tdekany Loc: Oregon

Lol!

selmslie wrote:

You would lose. Take a look at Photographic System Resolution and you might understand why.

selmslie Loc: Fernandina Beach, FL, USA

tdekany wrote:

Lol!

Being ignorant is only a sign that there is something you have not yet learned.

Being unwilling to learn is a character flaw.

TSHDGTL

Been working on this idea but not sure how intuitive it really is.

tdekany Loc: Oregon

selmslie wrote:

Being ignorant is only a sign that there is something you have not yet learned.

Being unwilling to learn is a character flaw.

Bla Bla Bla.....

Are you agreeing with Bipod that you can’t print 36x24 or larger from your FF gear? Did you forget to answer that question?

selmslie Loc: Fernandina Beach, FL, USA

tdekany wrote:

Bla Bla Bla.....

Are you agreeing with Bipod that you can’t print 36x24 or larger from your FF gear? Did you forget to answer that question?

I will answer after I see some evidence that you have read and understood the information I offered to you about system resolution. Otherwise, go away.