First "true" digital rangefinder camera

In article , Eric Stevens wrote:

Eric Stevens:
I wanted to focus on the pigeon's eye. Where within all the
surrounding foliage do you think the camera wanted to focus?
I can't remember but I do remember I had to finish
focussing with a manual adjustment.

nospam:
learn how to use the autofocus system properly.

pick a point and put it on the bird. it will focus faster and
more accurately than you could, regardless of screen.

Eric Stevens:
The D300 (as I used then) does not focus on points. Nor does the
D750 or anything else I know of.

nospam:
nonsense. of course they do.

as the saying goes: rtfm.

As it happens, I have the manual for the D750 at my left hand. I can
assure you that throughout the manual the text refers to the 51
rectangular focus areas as focus points. If you believe the manual
the focus points are rectangular. In fact some are cross-shaped and
others are rectangular. As is so often the case you are skimming
over the surface of things without asking yourself what it is that
actually lies underneath.

The feedback to the user is a rectangle, yes, but the actual focus sensor is
either two focus sensors in a vertical path or four sensor in a cross path.

The focus sensors get their image from a secondary mirror, that reflects the
light down to the sensor, which has 51 focus points, where 36 of them consists of
two focus sensors and 15 consists of four focus sensors.

So, the rectangles are there only for user feedback, they're not the actual phase
detection sensors. Phase detection sensors have microlenses in front of them,
that split the light into two (or four) paths, and the sensor can then detect the
phase difference of that light, and even determine if the object is front or back
focused.

--
Sandman

On 4/03/2015 4:10 a.m., nospam wrote:
In article , Me
wrote:

I wanted to focus on the pigeon's eye. Where within all the
surrounding foliage do you think the camera wanted to focus?
I can't remember but I do remember I had to finish focussing with a
manual adjustment.

learn how to use the autofocus system properly.

pick a point and put it on the bird. it will focus faster and more
accurately than you could, regardless of screen.

The D300 (as I used then) does not focus on points. Nor does the D750
or anything else I know of.

nonsense. of course they do.

as the saying goes: rtfm.

The AF system does not focus on "points".
It focuses on an "area" hopefully roughly the same as the area marked by
the AF brackets on the VF screen.

nikon calls them points. i'm going to go with what nikon calls them.

They do - but what they call them really isn't what they are.

http://www.nikonusa.com/en/Learn-And...i4pn/51-point-
autofocus-system.html
You can choose to use a single AF point to hone in on an exact spot
on your subject in which to focus on, or use all 51 AF points working
together to capture moving subjects. Using the Dynamic-area AF and
you¹ve also got the choice between 11, 9 or 21 AF points.
The "exact spot" as Nikon calls it equates to an area on the final image
several hundred pixels wide and high. Within that area there might be a
specular highlight on an eyeball of bird that you want in focus, but
other contrasty feature on a different plane that the camera chooses to
focus on instead. Some people expect the camera to know what they're
thinking.

his problem is he's using the wrong focus mode.

in other words, user error.

That's not unusual. I'm pretty sure that many people create their own
problems and end up blaming the camera, lens (or both) and/or end up in
a cycle of adjusting AF fine tune (on cameras which have this feature)
because they don't understand how the PDAF system works. And that's
just in single-servo single "point" mode.

In article ,
Sandman wrote:

the lcd on that thing sucks in comparison to
what's available today.

Not by much, no.

wrong.

lcds today are much brighter, have much higher resolution and are less
reflective. it's significant. anyone who says otherwise has vision
issues.



No, they all have really crappy LCD's for using as viewfinders.

no, they don't all have really crappy lcds.

Yes, they do.

maybe the ones you've used do but that's certainly not the case for all
cameras.

nikon started using 900k dot displays long ago and is now using
1200k dot displays. they're *very* good.

Not for focusing they're not, hence the need to zoom it.

the ability to zoom is a feature, not a bug.

try zooming a split prism. see how well that works out.

some evfs are also extremely good.

The one on the A7 is one of the very best, yet it is nowhere near the
fidelity
of an OVF.

this isn't about fidelity. try to stay on topic.

In article ,
Sandman wrote:

Sandman:
I've never ever owned a camera that shoots in f/8.222
when in shutter priority.

nospam:
bull****. they all do. automatic is free to pick *anything* and
not be restricted to 1/2 or 1/3 stop increments.

Sandman:
So they shoot in f/8.222 but record f/8 in the EXIF? So how do you
know what aperture it "really" used?

i've seen non-standard f/stops in images.

You said "they all do", so it should be in all images, yet I can't see it any
images from Nikon D70, D80, D800E, D3s, D4 or Sony A6000, A7 and RX1R. So
maybe
you need to support this claim, even though it is unrelated to your original
claim.

it's very related and stepless aperture is well known in the industry
and has been for *decades*, back to the days of film.

http://www.mir.com.my/rb/photography...mfgfg20/fg/fg2.
htm
The FG's metering system handles by microcomputer reads
center-weighted brightness, then instantaneously computes and sets
the ideal combination of stepless lens opening and stepless shutter
speed from 1 to 1/1000 second according to its scientifically
prearranged program.

http://www.mir.com.my/rb/photography/hardwares/classics/nikonfa/fa3.htm
Whatever it is, based on the instruction manual, the proper way in
shutter priority is stop the lens down to the minimum aperture
position (i.e., the largest f-number engraved on the lens barrel),
and the FA will automatically pick the matching lens aperture
steplessly for correct exposure.

http://articles.chicagotribune.com/1...nt/8503200898_
1_shutter-speed-slow-speed-camera
A--In the shutter-priority mode, the photographer chooses the shutter
speed suitable for the subject and the effect required, and the
camera automatically selects the correct aperture. The aperture
settings are stepless (not limited to full or half stops) to give
precise exposure even in rapidly changing light conditions.

http://photo.net/nikon-camera-forum/00LgqA
Incidentally, your aperture is also stepless in autoexposure modes (P
and S). Again, it will only display in full, 1/2 or 1/3 steps in the
finder, but it is stepless. So you could very well be using an
exposure of 1/120 at f/2.6 in P mode, but your finder will display
1/125 at f/2.8.

Sandman:
Also, you're describing an automatic setting, not
higher accuracy due to the control input.

nospam:
doesn't matter.

Sandman:
It does to the topic being discussed - i.e. the accuracy of the
aperture ring vs. the accuracy of the thumb wheel, both manual
controls.

you can't get the accuracy with a ring. it's that simple.

You just can't show how one is more accurate than the other. So more hot air.

already did.

you like to call things hot air whenever you feel like it. that doesn't
work. we all know you're full of ****.

nospam:
it's not opinion. the issues i described are all fixed with a
control wheel.

Sandman:
Yes, I know you think so, I have given you several occasions when
they don't. So it's your opinion. You are free to it.

it's not an opinion. it can be demonstrated in objective tests.

As has been shown, this is false.

nope. it hasn't been shown at all.

there will always be edge cases, but that doesn't change anything.

Indeed it does. "All of them" does not allow for edge cases.

nonsense. now you're playing semantic games.

In article , Me
wrote:

I wanted to focus on the pigeon's eye. Where within all the
surrounding foliage do you think the camera wanted to focus?
I can't remember but I do remember I had to finish focussing with a
manual adjustment.

learn how to use the autofocus system properly.

pick a point and put it on the bird. it will focus faster and more
accurately than you could, regardless of screen.

The D300 (as I used then) does not focus on points. Nor does the D750
or anything else I know of.

nonsense. of course they do.

as the saying goes: rtfm.

The AF system does not focus on "points".
It focuses on an "area" hopefully roughly the same as the area marked by
the AF brackets on the VF screen.

nikon calls them points. i'm going to go with what nikon calls them.

They do - but what they call them really isn't what they are.

that doesn't change anything i said.

http://www.nikonusa.com/en/Learn-And...i4pn/51-point-
autofocus-system.html
You can choose to use a single AF point to hone in on an exact spot
on your subject in which to focus on, or use all 51 AF points working
together to capture moving subjects. Using the Dynamic-area AF and
you¹ve also got the choice between 11, 9 or 21 AF points.
The "exact spot" as Nikon calls it equates to an area on the final image
several hundred pixels wide and high. Within that area there might be a
specular highlight on an eyeball of bird that you want in focus, but
other contrasty feature on a different plane that the camera chooses to
focus on instead. Some people expect the camera to know what they're
thinking.

it's a helluva lot smaller than a split-image prism and more accurate
too.

his problem is he's using the wrong focus mode.

in other words, user error.

That's not unusual. I'm pretty sure that many people create their own
problems and end up blaming the camera, lens (or both) and/or end up in
a cycle of adjusting AF fine tune (on cameras which have this feature)
because they don't understand how the PDAF system works. And that's
just in single-servo single "point" mode.

yep.

On Tue, 03 Mar 2015 15:57:25 -0500, nospam
wrote:

In article ,
Sandman wrote:

the lcd on that thing sucks in comparison to
what's available today.

Not by much, no.

wrong.

lcds today are much brighter, have much higher resolution and are less
reflective. it's significant. anyone who says otherwise has vision
issues.

None of this does anything to the loss of field of view inherent in
zooming in for more acurate focussing.



No, they all have really crappy LCD's for using as viewfinders.

no, they don't all have really crappy lcds.

Yes, they do.

maybe the ones you've used do but that's certainly not the case for all
cameras.

nikon started using 900k dot displays long ago and is now using
1200k dot displays. they're *very* good.

Not for focusing they're not, hence the need to zoom it.

the ability to zoom is a feature, not a bug.

try zooming a split prism. see how well that works out.

some evfs are also extremely good.

The one on the A7 is one of the very best, yet it is nowhere near the
fidelity
of an OVF.

this isn't about fidelity. try to stay on topic.
--

Regards,

Eric Stevens

In article , Eric Stevens
wrote:

the lcd on that thing sucks in comparison to
what's available today.

Not by much, no.

wrong.

lcds today are much brighter, have much higher resolution and are less
reflective. it's significant. anyone who says otherwise has vision
issues.

None of this does anything to the loss of field of view inherent in
zooming in for more acurate focussing.

that wasn't his claim. nevertheless, zooming is temporary. you don't
leave it zoomed in. zoom in, focus, zoom out. take photo.

In article , nospam wrote:

nospam:
the lcd on that thing sucks in comparison to what's available
today.

Sandman:
Not by much, no.

wrong.

Incorrect.

lcds today are much brighter, have much higher resolution and are
less reflective. it's significant. anyone who says otherwise has
vision issues.

For the purpose being discussed, not much has happened.

Sandman:
No, they all have really crappy LCD's for using as
viewfinders.

nospam:
no, they don't all have really crappy lcds.

Sandman:
Yes, they do.

maybe the ones you've used do but that's certainly not the case for
all cameras.

Nikon D800E, Nikon D4, Sony A7 and Sony RXR1.

nospam:
nikon started using 900k dot displays long ago and is now using
1200k dot displays. they're *very* good.

Sandman:
Not for focusing they're not, hence the need to zoom it.

the ability to zoom is a feature, not a bug.

No one has called it a bug.

try zooming a split prism. see how well that works out.

No need.

nospam:
some evfs are also extremely good.

Sandman:
The one on the A7 is one of the very best, yet it is nowhere near
the fidelity of an OVF.

this isn't about fidelity.

Yes it is, we're talking about manual focus, where viewing fidelity is very
important.

try to stay on topic.

I am.

--
Sandman

In article , nospam wrote:

In article
,

Sandman:
I've never ever owned a camera that shoots in
f/8.222 when in shutter priority.

nospam:
bull****. they all do. automatic is free to pick
*anything* and not be restricted to 1/2 or 1/3 stop
increments.

Sandman:
So they shoot in f/8.222 but record f/8 in the EXIF?
So how do you know what aperture it "really" used?

nospam:
i've seen non-standard f/stops in images.

Sandman:
You said "they all do", so it should be in all images, yet I can't
see it any images from Nikon D70, D80, D800E, D3s, D4 or Sony
A6000, A7 and RX1R. So maybe you need to support this claim, even
though it is unrelated to your original claim.

it's very related

No it is not related to the question about accuracy for two manual control
methods of aperture.

and stepless aperture is well known in the
industry and has been for *decades*, back to the days of film.

Cool, so how come none of my cameras seem to employ it when "they all do"?

http://photo.net/nikon-camera-forum/00LgqA Incidentally, your
aperture is also stepless in autoexposure modes (P and S). Again,
it will only display in full, 1/2 or 1/3 steps in the finder, but
it is stepless. So you could very well be using an exposure of
1/120 at f/2.6 in P mode, but your finder will display 1/125 at
f/2.8.

Omitted:

"For Nikon cameras that can set the aperture via the lens aperture ring, you
also have stepless aperture control in M mode. Very precise exposure control
was always possible, even in the 1960's."

Sandman:
Also, you're describing an automatic setting, not
higher accuracy due to the control input.

nospam:
doesn't matter.

Sandman:
It does to the topic being discussed - i.e. the
accuracy of the aperture ring vs. the accuracy of the thumb
wheel, both manual controls.

nospam:
you can't get the accuracy with a ring. it's that simple.

Sandman:
You just can't show how one is more accurate than the other. So
more hot air.

already did.

Incorrect.

you like to call things hot air whenever you feel like it. that
doesn't work. we all know you're full of ****.

No, I like to call them hot air when they're empty unsupported claims.

nospam:
it's not opinion. the issues i described are all
fixed with a control wheel.

Sandman:
Yes, I know you think so, I have given you several
occasions when they don't. So it's your opinion. You are free
to it.

nospam:
it's not an opinion. it can be demonstrated in objective tests.

Sandman:
As has been shown, this is false.

nope. it hasn't been shown at all.

Incorrect.

nospam:
there will always be edge cases, but that doesn't change
anything.

Sandman:
Indeed it does. "All of them" does not allow for edge cases.

nonsense. now you're playing semantic games.

Incorrect. Stop making explicit claims if you don't mean them. You made a
series of claims, some were valid, some were not. "All of them" was a false
claim.

--
Sandman

In article , Me wrote:

nospam:
http://www.nikonusa.com/en/Learn-And...i4pn/51-point-
autofocus-system.html You can choose to use a single AF point to
hone in on an exact spot on your subject in which to focus on, or
use all 51 AF points working together to capture moving subjects.
Using the Dynamic-area AF and you¹ve also got the choice between
11, 9 or 21 AF points.

The "exact spot" as Nikon calls it equates to an area on the final
image several hundred pixels wide and high.

No it doesn't. A focus point is the converging point of two or more focusing
sensors. The rectangle you see in the viewfinder is only for you to know where
those focusing sensors are located.



--
Sandman