Lightroom vs. Apertu Curves

nospam wrote:
In article , Floyd L. Davidson
wrote:

Here's an example of a feature I'm missing in Lightroom.

I use curves extensively, it's the holy grail of exposure editing.
If you're not using it, start using it!

A curves tool does not edit exposure

Captain literal strikes again.

The fact is that a curves tool does not change
"exposure" (brightness is the correct term). It is a
tone mapping tool.

adjusting exposure is not the same as adjusting brightness.

Isn't that rather obvious from what I said.

no. exposure does not change brightness or contrast. it changes
exposure which is why it's called exposure and not brightness or
contrast.

"Exposure"
can only be changed with shutter speed and aperture,
before the picture is taken.

in an ideal world, it's correct when taken, but that's almost never the
case, which is why can also be adjusted afterwards.

Which does not stop
several software programs from incorrectly labeling the
brightness adjustment as "exposure".

maybe some apps do but not all.

in fact, adjusting brightness or contrast is rarely needed, since
levels & curves do a much better and more effective job.

Curves, as I've noted, simply doesn't do that and
therefore cannot be "more effective".

it does do that, and is more effective because some implementations of
brightness and contrast can clip.

Until you understand that, all you'll do is make silly
statements such as you did for the rest of your post.

take your own advice.

you don't use the software being discussed, which would be step one.

I suppose for someone who doesn't understand it that would seem to
be true. It isn't.

so far, what you've said does not apply to the software he's using.

It applies directly. Your understanding of software is very limited.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

nospam wrote:
In article , Sandman
wrote:

Floyd L. Davidson:
The fact is that a curves tool does not change "exposure"
(brightness is the correct term). It is a tone mapping tool.

nospam:
adjusting exposure is not the same as adjusting brightness.

Isn't that rather obvious from what I said. "Exposure" can only be
changed with shutter speed and aperture, before the picture is
taken. Which does not stop several software programs from
incorrectly labeling the brightness adjustment as "exposure".

God, you're ignorant.

An "exposure" slider in software is *not* a brightness editor. It does
*not* edit brightness. A true brightness slider edits all color values
uniformly, increasing or decreasing the color value of every pixel.

This is how the brightness slider have worked in Photoshop since the dawn
of time, until CS5 (I think) where they changed it, but you can still use
it if you click the "Use legacy" checkbox.

it changed in cs3.

The new PS brightness slider spreads the spectrum from the bottom, meaning
that darker tones are changed less than brighter tones.

greatly simplifying, brightness is levels and contrast is curves, with
a single easy to use slider adjust for each.

An *exposure* slider focuses on the midrange, trying to emulate (yes, Eric,
this is where emulate is the proper word) how the exposure of the camera
works.

actually it focuses (ahem) on the highlights and shadows by protecting
them from clipping. the midrange isn't as critical.

it does emulate what would happen in the camera and is effectively the
same had you changed exposure in camera.

With the base values of rgb(0, 30, 250), these are the results:

True brightness +10: rgb(10, 40, 255)
New PS brightness +10: rgb(3, 36, 255)
Exposure +10: rgb(3, 40, 253)

Using curves, you can edit the whitepoint, which works exactly like the new
brightness editor in PS, meaning it extends the range beyond the
colorspace.

eh? what does that even mean?

No one wants or use a brightness editor, they're worthless. That's why
exposure and curves white point gives you the control needed. I much prefer
the curves way, as anyone should.

the old style brightness/contrast were broken.

they've long been fixed, with the legacy option still there for those
who learned the broken behaviour and don't want to learn how it should
be.

nospam:
in fact, adjusting brightness or contrast is rarely needed, since
levels & curves do a much better and more effective job.

Curves, as I've noted, simply doesn't do that and therefore cannot
be "more effective".

It does, you just don't know anything about these matters.

he's never used the software being discussed.

Floyd L. Davidson:
Until you understand that, all you'll do is make silly
statements such as you did for the rest of your post.

nospam:
take your own advice.

you don't use the software being discussed, which would be step
one.

I suppose for someone who doesn't understand it that would seem to
be true. It isn't.

Ironic.

isn't it?

You two can call it whatever you like, all of it is "brightness" and
not a bit of it is exposure. Exposure is how many photons are captured
by the sensor...

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

In article , Floyd L. Davidson
wrote:

blown out in 8 bit but not in 11, 12 or 14 bits. If this was a
Hasselblad shot, there would be even more data hiding in the
extended range outside the scope of your monitor.

It has nothing to do with color space.

When working with the RAW conversion stage, set brightness (or
"exposure" if they call it that) correctly. Gamma and other
parameters may interact with it to some degree.

The primary reason for adjusting brightness and gamma, or in fact
for using a curves tool too, in the converter stage rather than
later, is because interpolation the RAW data produces a 16 bit depth
RGB image. If the image is or has been converted to JPEG it is in
an 8 bit format. But, even in a 16 bit format the histogram will
almost always show values of 0 to 255 (8 bit depth) even if the
actual data set being edited is larger.

Captain obvious has emerged again. So, what's the problem here, you can't
understand what you read or just don't care?

The mere concept of having the information presented via a "curves"
tool is what is confusing you. They might well show it to you in
that context, but what they are doing is allowing you to go back to
the RAW converter and change brightness. If you are aware of that,
conceptually, it isn't at all hard to understand.

No one is trying to "understand" anything here, ignorant Floyd. You're just
posting obvious basic stuff that no one asked about because you can't read
to save your life.

Same old, same old, ey?

Yep, same old ****. It's pretty obvious who does
understand it and who does not.

something which becomes clearer with each post you make.

you're talking about software you've never used and are trying to tell
people who have been using it for many years that they don't understand
it.

that's really ****ed up.

In article , Floyd L. Davidson
wrote:

Perhaps a different example where you didn't have blown highlights
might have been better for the purposes of this discussion. The
image you used had too many exposure issues (see above) to truly
illustrate your point.

Not at all. I am not interested in the blown out parts, I am interested in
the parts that aren't blown out, but can't fit in a 8 bit colorspace and
thus *appear* blown out. Parts that *are* blown out in 8 bit but not in
11,
12 or 14 bits. If this was a Hasselblad shot, there would be even more
data
hiding in the extended range outside the scope of your monitor.

It has nothing to do with color space.

When working with the RAW conversion stage, set
brightness (or "exposure" if they call it that)
correctly. Gamma and other parameters may interact with
it to some degree.

brightness != exposure.

lightroom used to have brightness, but it was removed in the current
version since exposure works much better.

brightness can be put back by choosing pv 2010 (or earlier), but that's
not recommended.

I'll tell you a secret: you cannot, under any
circumstances, change the exposure of an image with post
processing software.

nobody expects that it's going to go back and change the f/stop or
shutter speed.

you can't admit you don't know how lightroom works, so you have to move
the goalposts to camera exposure.

The primary reason for adjusting brightness and gamma,
or in fact for using a curves tool too, in the converter
stage rather than later, is because interpolation the
RAW data produces a 16 bit depth RGB image. If the
image is or has been converted to JPEG it is in an 8 bit
format. But, even in a 16 bit format the histogram will
almost always show values of 0 to 255 (8 bit depth) even
if the actual data set being edited is larger.

there is no later stage.

everything is done in raw (assuming original raw) using floating point
math and prophoto rgb colour space. always.

it is never converted to jpeg until the image is exported *after* all
adjustments are complete.

But if it has been converted, and is now being edited...

it hasn't been converted. all adjustments are applied to the raw data.

there is no jpeg until the user exports one, and that's if they decide
to do that. they might not, which means there won't ever be a jpeg.

Also "everything is done in raw" is just not true.

you're wrong. it is true.

that's how lightroom (and aperture) works.

There is
not color space for raw sensor data either.

the colour space used is pro photo rgb.

You are confusing the RGB image with the raw sensor data.

i'm not confusing anything.

i've been using lightroom since it was beta nearly a decade ago and i
know *very* well how it works.

you have never used lightroom and do not know how it works.

if anyone is confused, it is you.

Note that the horizontal scale on an histogram is rarely
ever marked in fstops. Cameras generally have a very
non linear scale while editors are "somewhat" close.
But just because there are 6 or 8 or 16 vertical index
marks on a histogram does not suggest the number of
fstops of range covered. (Histograms of JPEG images
cover about 9.5 fstops.)

true but not relevant.

True and very relevant, given how confused you and
Sandman are.

i'm not confused at all, and although i can't speak for sandman, he
does not seem to be confused either, other than having a question about
this particular issue.

again, both he and i have used lightroom. you have not.

The mere concept of having the information presented via
a "curves" tool is what is confusing you. They might
well show it to you in that context, but what they are
doing is allowing you to go back to the RAW converter
and change brightness. If you are aware of that,
conceptually, it isn't at all hard to understand.

again, you don't understand how the software works.

there is no going back to the raw converter. everything is always done
in raw, and in a non-destructive manner.

Do you even know what "non-destructive" means?

yes.

do you?

based on what you've posted, you do not.

It literally means going back and re-doing the
interpolation of raw sensor data with a raw converter.

yes it does.

did you have a point or are you going to recite the obvious about
what's already known?

there are specific sliders for exposure (not brightness) and contrast
but it can also be done with curves and more work.

You can't change exposure with processing software.

nobody expects it to go back and change the f/stop.

that's just more of your weaseling because you can't admit you don't
know how lightroom works.

And
a curves tool does not change the brightness nor the
contrast of an image as such. It remaps which tonal
levels are assigned to which already defined levels. It
doesn't stretch the range. It technically does not
compress the range either, but the effect is the same.

contrast is just an s curve.

there are a couple of presets but the user can alter it any way they
want.

In article , Floyd L. Davidson
wrote:

Until you understand that, all you'll do is make silly
statements such as you did for the rest of your post.

take your own advice.

you don't use the software being discussed, which would be step one.

I suppose for someone who doesn't understand it that would seem to
be true. It isn't.

so far, what you've said does not apply to the software he's using.

It applies directly. Your understanding of software is very limited.

hilarious.

i've been using multiple versions of lightroom for nearly a decade.

you have never used it at all.

if anyone's understanding is limited about how it works, it would be
you.

In article , Floyd L. Davidson
wrote:


Floyd L. Davidson:
Until you understand that, all you'll do is make silly
statements such as you did for the rest of your post.

nospam:
take your own advice.

you don't use the software being discussed, which would be step
one.

I suppose for someone who doesn't understand it that would seem to
be true. It isn't.

Ironic.

isn't it?

You two can call it whatever you like, all of it is "brightness" and
not a bit of it is exposure.

i'm calling what adobe calls it, and that's exposure. it is *not* the
same as brightness.

Exposure is how many photons are captured
by the sensor...

more of your weaseling.

nobody expects to go back and change the f/stop or shutter speed.

changing exposure in lightroom looks the same as if the exposure in the
camera was changed by the same amount.

nothing is perfect, but nobody is going to notice a difference by
looking at the results unless it's extreme (and even then, probably
not).

On 2014-08-12, Sandman wrote:
In article , Eric Stevens wrote:

But, alas, no extended range here (or with the poorer version of
curves) so no way - as far as I can make out - to actually access
all that glorious image data from within Lightroom.

Anyone knows if I've missed something?

Before I comment, I would like to try another approach. Can you post
a copy of the original in an editable form?

Certainly.

http://sandman.net/files/DSC01476.ARW

First: thanks for bringing some photo discutions back in this group.


I have a few newbie questions. Not criticicsms, no openings for a religious
debate, just a few questions from someone with more knowledge in IT than in
photo...

You put that image in ARW format, which - as far as I can see - is a Sony
'raw' format, right?

Now, from my IT point of view (opening, interpreting, converting the file) a
'raw' format is NOT a format. Not in the sense that there is a clear unique
data format definition. Every manufacturor has their own 'raw' format, some
even different ones in different models/generations of their camera's.
Of course, the ARW format seems to be from Sony (even my Linux tells me so),
and probably doesn't pretend to be universal. But:

1. is the ARW format that common that you would assume anyone can read it, or
do you happen to know that he also has a Sony ?

2. I once saw a definition for a type of an open raw format, supposedly
independant from manufactorors: DNG. It had a few flaws, but the idea was
there. Is there still no tendency to go to such formats in exchanges, or has
everyone just given in and accept that each brand talks it's own language?


--
When in doubt, use brute force.
-- Ken Thompson

On 2014-08-12 21:29:03 +0000, Rikishi42 said:

On 2014-08-12, Sandman wrote:
In article , Eric Stevens wrote:

But, alas, no extended range here (or with the poorer version of
curves) so no way - as far as I can make out - to actually access
all that glorious image data from within Lightroom.

Anyone knows if I've missed something?

Before I comment, I would like to try another approach. Can you post
a copy of the original in an editable form?

Certainly.

http://sandman.net/files/DSC01476.ARW

First: thanks for bringing some photo discutions back in this group.


I have a few newbie questions. Not criticicsms, no openings for a religious
debate, just a few questions from someone with more knowledge in IT than in
photo...

You put that image in ARW format, which - as far as I can see - is a Sony
'raw' format, right?

Jonas didn't put that image in ARW format, he captured it in that
format in his camera. Many of us shoot and post process our images in
whatever RAW format our cameras use.

Now, from my IT point of view (opening, interpreting, converting the file) a
'raw' format is NOT a format.

It is absolutely a file format, one a specific purpose, but a file
format bone the less. Be it NEF, CR2, ARW, or RAF.
As he posted it here it was not meant to be viewed as one would a JPEG,
PNG or TIF. He was sharing the unmolested, uncompressed source data for
that image.

Not in the sense that there is a clear unique data format definition.
Every manufacturor has their own 'raw' format, some even different ones
in different models/generations of their camera's.

Yup!

Of course, the ARW format seems to be from Sony (even my Linux tells me so),
and probably doesn't pretend to be universal. But:

1. is the ARW format that common that you would assume anyone can read it, or
do you happen to know that he also has a Sony ?

It's a RAW format and most of us use software which can process RAW
files regardless of source. So if asked for original source files a
willing photographer might provide them. Recently three of us have have
shared RAW files, 2 NEFs and the ARW discussed here.

2. I once saw a definition for a type of an open raw format, supposedly
independant from manufactorors: DNG.

That is an Adobe RAW file type, and it is in general use. Lightroom can
be configured to convert RAW file to DNG on import, and Adobe also
provides the free DNG convertor.

It had a few flaws, but the idea was there. Is there still no tendency
to go to such formats in exchanges, or has
everyone just given in and accept that each brand talks it's own language?

Yes. Sensors and processors are different so RAW files for cameras
supporting RAW will change with each new release, be it NEF, CR2, ARW,
RAF, etc.



--
Regards,

Savageduck

In article , Rikishi42
wrote:

I have a few newbie questions. Not criticicsms, no openings for a religious
debate, just a few questions from someone with more knowledge in IT than in
photo...

You put that image in ARW format, which - as far as I can see - is a Sony
'raw' format, right?

it is.

Now, from my IT point of view (opening, interpreting, converting the file) a
'raw' format is NOT a format. Not in the sense that there is a clear unique
data format definition. Every manufacturor has their own 'raw' format, some
even different ones in different models/generations of their camera's.
Of course, the ARW format seems to be from Sony (even my Linux tells me so),
and probably doesn't pretend to be universal. But:

each camera has its own raw format, even from the same company.

it has to, since it's basically a dump of the sensor, with some extra
information, such as the chromaticity of the filters on the sensor plus
the usual exif metadata (camera settings, gps if available, etc.).

any time the sensor changes, the raw format must also change. a nikon
36 megapixel raw is not going to be the same as a canon 18 megapixel
raw.

1. is the ARW format that common that you would assume anyone can read it, or
do you happen to know that he also has a Sony ?

short answer: yes.

long answer:
most people have photo software that supports raw, or raw support is
built into their operating system, which means just about all apps can
handle raw.

the raw conversion software knows about all of the camera's raw formats
made to date (with rare exception for oddball cameras that almost
nobody has). it's a giant list and getting bigger all the time.

there is a brief wait from when a new camera is introduced until it's
supported in the various raw converters. some converters get support
quicker than others.

here's what adobe camera raw supports:
http://helpx.adobe.com/photoshop/camera-raw.html

another raw converter is dcraw, and the list of cameras it supports is
he
http://www.cybercom.net/~dcoffin/dcraw/

the exact conversion parameters to make the final image are up to the
user. exposure (despite what some people here claim), contrast, white
balance, etc., can all be adjusted in software. what was set on the
camera does not matter.

different raw converters produce different looking results. camera raw
is widely considered to be the best for many reasons, but like
anything, not everyone agrees.

2. I once saw a definition for a type of an open raw format, supposedly
independant from manufactorors: DNG. It had a few flaws, but the idea was
there. Is there still no tendency to go to such formats in exchanges, or has
everyone just given in and accept that each brand talks it's own language?

everything has flaws. nothing is perfect.

anyway, some cameras output dng directly.

other cameras have a native raw format.

some users choose to convert the native raw format to dng (which is
lossless) while most users directly use the native raw format since
there's very little advantage to converting to dng. it's an extra step.

many users don't even shoot raw and just shoot jpeg, which is good
enough most of the time and takes up a lot less space.

On 2014-08-12 22:03:23 +0000, Savageduck said:

On 2014-08-12 21:29:03 +0000, Rikishi42 said:

On 2014-08-12, Sandman wrote:
In article , Eric Stevens wrote:

But, alas, no extended range here (or with the poorer version of
curves) so no way - as far as I can make out - to actually access
all that glorious image data from within Lightroom.

Anyone knows if I've missed something?

Before I comment, I would like to try another approach. Can you post
a copy of the original in an editable form?

Certainly.

http://sandman.net/files/DSC01476.ARW

First: thanks for bringing some photo discutions back in this group.


I have a few newbie questions. Not criticicsms, no openings for a religious
debate, just a few questions from someone with more knowledge in IT than in
photo...

You put that image in ARW format, which - as far as I can see - is a Sony
'raw' format, right?

Jonas didn't put that image in ARW format, he captured it in that
format in his camera. Many of us shoot and post process our images in
whatever RAW format our cameras use.

Now, from my IT point of view (opening, interpreting, converting the file) a
'raw' format is NOT a format.

It is absolutely a file format, one a specific purpose, but a file
format bone the less. Be it NEF, CR2, ARW, or RAF.
As he posted it here it was not meant to be viewed as one would a JPEG,
PNG or TIF. He was sharing the unmolested, uncompressed source data for
that image.

Sorry for the omission and typo in the preceding paragraph. The above
should read; "...one meant for a specific purpose,..."; and "none the
less" not "bone the less".


Not in the sense that there is a clear unique data format definition.
Every manufacturor has their own 'raw' format, some even different ones
in different models/generations of their camera's.

Yup!

Of course, the ARW format seems to be from Sony (even my Linux tells me so),
and probably doesn't pretend to be universal. But:

1. is the ARW format that common that you would assume anyone can read it, or
do you happen to know that he also has a Sony ?

It's a RAW format and most of us use software which can process RAW
files regardless of source. So if asked for original source files a
willing photographer might provide them. Recently three of us have have
shared RAW files, 2 NEFs and the ARW discussed here.

2. I once saw a definition for a type of an open raw format, supposedly
independant from manufactorors: DNG.

DNG is an Adobe RAW file type, and it is in general use. Lightroom can
be configured to convert RAW file to DNG on import, and Adobe also
provides the free DNG convertor.

It had a few flaws, but the idea was there. Is there still no tendency
to go to such formats in exchanges, or has
everyone just given in and accept that each brand talks it's own language?

Yes. Sensors and processors are different so RAW files for cameras
supporting RAW will change with each new release, be it NEF, CR2, ARW,
RAF, etc.


--
Regards,

Savageduck