Lenses and sharpening

In article , Floyd L. Davidson
wrote:


No one who understood what we were trying to talk about would claim
that a JPG conversion is a reversible process.
Â...but that genius Floyd did.
I've had a look and I cant see where. Could you refer
me to the
message?

With pleasure.

That wasnâEUR(Tm)t too tough to find:
Posted: Mon, 15 Sep 2014 13:44:18 -0500
Message ID:

Wherein Floyd stated the following:

âEURoeA non-destructive workflow means you can *undo* and then *redo*.

That is not a reversible function.

For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.

If the sharpening is done with UnsharpMask that cannot
be done. USM is not reversible.âEUR�

Note, the words, âEURoesave it as a JPEG,âEUR�.

As I said, that genius Floyd did.

So we now we know you can't read.

that would be you.

What I said was that *high pass sharpen is reversible*.
It is, even if a few people are unable to either understand
or accept that it is.

in a non-destructive workflow, *everything* is reversible.

that's basically the whole point.

In article , Floyd L. Davidson
wrote:

Sandman and nospam remind me of a kid named Danny that went through
grade school with me. In the second grade we did spelling lists every
week. The "test" was the teacher read off the words, and we wrote them
down, and then we "corrected" our own list. The teacher went down the
list and spelled each word in turn.

Every time the teacher spelling it different than Danny, he would
excitedly raise his hand and start saying, "Miss Finholm, you made
a 'stake." She would, every time, have to convince him that his
spelling actually was wrong.

actually that describes you perfectly.

you hone in on irrelevant details, such as revertible versus reversible
versus undo, and worse, you get it *wrong*.

Your comment does not support your claim.

it does, and i can dig up many of your posts to prove it.

however, from memory,
you said some things a year or so ago about mac and windows that were
totally false and laughably so.

some time before that, maybe two years ago, you said there could never
be an internal wifi antenna on an slr because the camera body is metal.
that too is wrong. there are over a billion devices with a metal body,
including laptops, tablets and smartphones, and work just fine with
wifi. all it takes is an antenna aperture or putting the antenna on the
outside rather than the inside (and still not visible). it's trivial to
do.

more recently, your comments about photoshop are *way* off, as are the
ones about lightroom and a non-destructive workflow.

there are many, many others.

to your credit, you do get some stuff right, but the problem is you
frequently talk about stuff you know nothing about, such as photoshop,
lightroom, mac and windows.

Moreover, the
reversible nature of sharpen tools vs other types of
processes is important to the OP, even if some folks
never aspire to a level of photography where it becomes
important.

another one of your insults.

why is it that top photographers worldwide use a non-destructive
workflow, if it's only for idiots, or as you put it, for cartoon
characters?

why is it that photoshop is used by the vast majority of professional
photographers and a significant number of prosumers?

why is it that you can't accept that there are other ways to do things,
including ways that offer substantial workflow improvements over your
outdated primitive ways? your way is not the *only* way.

On Wed, 17 Sep 2014 19:20:02 -0700, Savageduck
wrote:

On 2014-09-18 01:00:46 +0000, Eric Stevens said:

On Wed, 17 Sep 2014 06:05:14 -0700, Savageduck
wrote:
On 2014-09-17 09:22:00 +0000, Eric Stevens said:
On Tue, 16 Sep 2014 22:27:43 -0700, Savageduck
wrote:
On 2014-09-17 04:08:19 +0000, Eric Stevens said:
On Tue, 16 Sep 2014 07:53:15 -0700, Savageduck
wrote:
On 2014-09-16 10:36:29 +0000, (Floyd L. Davidson) said:


--- snip ---

The reverse process performed on a lossy, compressed JPEG is not going
to reverse the HPF to return to the original state. That was lost once
the save was executed.

That's why I never included a conversion to JPG in my example of a
reversible process.

?but that genius Floyd did.


--- snip ---

No one who understood what we were trying to talk about would claim
that a JPG conversion is a reversible process.

?but that genius Floyd did.

I've had a look and I cant see where. Could you refer me to the
message?

With pleasure.

That wasn’t too tough to find:
Posted: Mon, 15 Sep 2014 13:44:18 -0500
Message ID:

Wherein Floyd stated the following:

“A non-destructive workflow means you can *undo* and then *redo*.

That is not a reversible function.

For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.

If the sharpening is done with UnsharpMask that cannot
be done. USM is not reversible.”

Note, the words, “save it as a JPEG,”.

As I said, that genius Floyd did.

Yes, I found that text, but I don't think that it means what you seem
to think it means. He wasn't claiming that JPEG is fully reversible:
everybody knows that it isn't.

Based on what Floyd has been saying all along, the obvious series of
processes would be:

1. Sharpen image.

2. Save file as TIFF

3. Apply Gaussian blur to TIFF image to recover original
image sharpness.

This series of processes is possible if you sharpen with a high pass
filter but not possible if you sharpen with unsharp mask. i.e. the
original image is recoverable if you sharpen with the high pass
filter.

Floyd then went further and, as you quoted, proposed an alternative
series of processes:

1. Sharpen image.

2. Save file as JPEG

3. Apply Gaussian blur to JPEG image to recover original
image sharpness.

.... and claimed that, again, this process also is possible if you
sharpen with a high pass filter but not possible if you sharpen with
unsharp mask. i.e. the original image is recoverable if you sharpen
with the high pass filter.

I understood him to be saying that inspite of the losses of a JPEG
conversion, recovery of the original sharpness is possible if the
original sharpening process used a high pass filter. That while saving
as a JPEG will always cause losses, this will not prevent a Gaussian
blur operation from recovering the sharpness of the original image.


--

Regards,

Eric Stevens

On Wed, 17 Sep 2014 22:47:10 -0400, nospam
wrote:

In article 20140917192002703-savageduck1@REMOVESPAMmecom, Savageduck
wrote:


No one who understood what we were trying to talk about would claim
that a JPG conversion is a reversible process.

?but that genius Floyd did.

I've had a look and I cant see where. Could you refer me to the
message?

With pleasure.

That wasn¹t too tough to find:
Posted: Mon, 15 Sep 2014 13:44:18 -0500
Message ID:

Wherein Floyd stated the following:

³A non-destructive workflow means you can *undo* and then *redo*.

That is not a reversible function.

For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.

If the sharpening is done with UnsharpMask that cannot
be done. USM is not reversible.²

Note, the words, ³save it as a JPEG,².

As I said, that genius Floyd did.

and that genius is completely wrong.

a non-destructive workflow doesn't 'destruct' so there's really nothing
to 'undo'.

all of the adjustments are done en masse, with the item in question
simply removed (or its parameters altered), which means it's never
'done'.

If it were never done, how come you think it can be undone?
--

Regards,

Eric Stevens

On Thu, 18 Sep 2014 00:01:24 -0400, nospam
wrote:

In article , Eric Stevens
wrote:


If you make the adjustments in Photoshop with a non-destructive
workflow there is no use of sidecar files or catalog entries as in
Lightroom.

True, but this has nothing to do with whether a process is
reversible or not.

Of course it does. Non-destructive adjustments means they are reversible.

Not in the strictly technical sense in which Floyd was using the term.

that's the whole problem.

floyd cannot acknowledge that there are other completely valid meanings.

If you want to argue with what he said then you have to use the same
meaning that he did.

A tip for the future - whenever Floyd says anything, it's a safe bet to
assume the exact opposite is true.

Not so, I'm afraid.

in many cases, it is.

he spouts about stuff he's never used and as a result, gets some very
fundamental things wrong.
--

Regards,

Eric Stevens

On Wed, 17 Sep 2014 21:15:33 -0700, John McWilliams
wrote:

On 9/17/14 PDT, 4:42 PM, Floyd L. Davidson wrote:


Way too much.

You've outdone yourself in obstinacy, meanness and boorishness.

Your grasp of sharpening is woefully outdated and your definition of
reversibility is stilted.

It's strictly accurate.

Sheesh!
--

Regards,

Eric Stevens

In article , Eric Stevens
wrote:

That wasn¹t too tough to find:
Posted: Mon, 15 Sep 2014 13:44:18 -0500
Message ID:

Wherein Floyd stated the following:

³A non-destructive workflow means you can *undo* and then *redo*.

That is not a reversible function.

For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.

If the sharpening is done with UnsharpMask that cannot
be done. USM is not reversible.²

Note, the words, ³save it as a JPEG,².

As I said, that genius Floyd did.

and that genius is completely wrong.

a non-destructive workflow doesn't 'destruct' so there's really nothing
to 'undo'.

all of the adjustments are done en masse, with the item in question
simply removed (or its parameters altered), which means it's never
'done'.

If it were never done, how come you think it can be undone?

it's not undone. it's redone with different parameters.

it's not a pixel level editor, it's a parametric editor.

do we have to go through the discussion about rendering again?

In article , Eric Stevens
wrote:

If you make the adjustments in Photoshop with a non-destructive
workflow there is no use of sidecar files or catalog entries as in
Lightroom.

True, but this has nothing to do with whether a process is
reversible or not.

Of course it does. Non-destructive adjustments means they are reversible.

Not in the strictly technical sense in which Floyd was using the term.

that's the whole problem.

floyd cannot acknowledge that there are other completely valid meanings.

If you want to argue with what he said then you have to use the same
meaning that he did.

i used the common meaning of the term reversible.

he is using his own narrow definition and intentionally dismissing
*anything* else.

On 2014-09-18 05:05:12 +0000, Eric Stevens said:

On Wed, 17 Sep 2014 19:20:02 -0700, Savageduck
wrote:

On 2014-09-18 01:00:46 +0000, Eric Stevens said:

On Wed, 17 Sep 2014 06:05:14 -0700, Savageduck
wrote:
On 2014-09-17 09:22:00 +0000, Eric Stevens said:
On Tue, 16 Sep 2014 22:27:43 -0700, Savageduck
wrote:
On 2014-09-17 04:08:19 +0000, Eric Stevens said:
On Tue, 16 Sep 2014 07:53:15 -0700, Savageduck
wrote:
On 2014-09-16 10:36:29 +0000, (Floyd L. Davidson) said:


--- snip ---

The reverse process performed on a lossy, compressed JPEG is not going
to reverse the HPF to return to the original state. That was lost once
the save was executed.

That's why I never included a conversion to JPG in my example of a
reversible process.

?but that genius Floyd did.


--- snip ---

No one who understood what we were trying to talk about would claim
that a JPG conversion is a reversible process.

?but that genius Floyd did.

I've had a look and I cant see where. Could you refer me to the
message?

With pleasure.

That wasnÂ’t too tough to find:
Posted: Mon, 15 Sep 2014 13:44:18 -0500
Message ID:

Wherein Floyd stated the following:

“A non-destructive workflow means you can *undo* and then *redo*.

That is not a reversible function.

For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.

If the sharpening is done with UnsharpMask that cannot
be done. USM is not reversible.”

Note, the words, “save it as a JPEG,”.

As I said, that genius Floyd did.

Yes, I found that text, but I don't think that it means what you seem
to think it means. He wasn't claiming that JPEG is fully reversible:
everybody knows that it isn't.

It means exactly what he intended it to mean.
You are putting words in his mouth when you become his advocate and say
that he wasn’t claiming that the JPEG is fully reversible. That is your
spin on what he didn’t say.

Here I was hoping you weren’t going to say that he didn’t mean what he
said, or that I read it wrong. The problem is, Floyd always says what
he means doesn’t he?

Based on what Floyd has been saying all along, the obvious series of
processes would be:

1. Sharpen image.

2. Save file as TIFF

However, that isn’t what he said. From his statement he said;
“For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.�

That seems pretty clear, and Floyd means what he says.

3. Apply Gaussian blur to TIFF image to recover original
image sharpness.

This series of processes is possible if you sharpen with a high pass
filter but not possible if you sharpen with unsharp mask. i.e. the
original image is recoverable if you sharpen with the high pass
filter.

Floyd then went further and, as you quoted, proposed an alternative
series of processes:

1. Sharpen image.

2. Save file as JPEG

3. Apply Gaussian blur to JPEG image to recover original
image sharpness.

However you challenged me to support my claim that he actually said
that. Remember? Yo said yourself; “No one who understood what we we
trying to talk about would claim that a JPG conversion is a reversible
process.�
…but Floyd did, and Floyd knows what he is talking about, and he means
what he says.

... and claimed that, again, this process also is possible if you
sharpen with a high pass filter but not possible if you sharpen with
unsharp mask. i.e. the original image is recoverable if you sharpen
with the high pass filter.

I understood him to be saying that inspite of the losses of a JPEG
conversion, recovery of the original sharpness is possible if the
original sharpening process used a high pass filter. That while saving
as a JPEG will always cause losses, this will not prevent a Gaussian
blur operation from recovering the sharpness of the original image.

Regardless of what you understood him to mean, what did he actually
say? I doubt that Floyd would be please with anybody being so bold as
to paraphrase his words. He does mean what he says doesn’t he?

I certainly don’t have the engineering background you and Floyd have,
but I have a solid education in the sciences and I have had years of
experience in microbiology and lab work, all of which strangely led me
down another career path solidly entrenched in investigation. One of
the things I have been quite good at over the last 30+ years is
remembering and pinning down inconstancies in statements. They can be
revealing. So rather than put words in his mouth, let Floyd's words
stand on their own without your interpretation.

--
Regards,

Savageduck

Savageduck wrote:
On 2014-09-18 05:05:12 +0000, Eric Stevens said:
Yes, I found that text, but I don't think that it
means what you seem
to think it means. He wasn't claiming that JPEG is fully reversible:
everybody knows that it isn't.

It means exactly what he intended it to mean.
You are putting words in his mouth when you become his
advocate and say that he wasnâEUR(Tm)t claiming that the JPEG
is fully reversible. That is your spin on what he
didnâEUR(Tm)t say.

Yes it means exactly what I intended it to mean, which
is very obvious to Eric, but not to you.

There is no claim that JPEG is "fully reversible", or
for that matter even partially reversible.

All the BS is *you not being able to understand*.

an alternative
series of processes:
1. Sharpen image.
2. Save file as JPEG
3. Apply Gaussian blur to JPEG image to recover
original
image sharpness.

Actually that is not quite what I said. I said the
sharpen is reversible. I did not say fully reversible,
I did not say the "original image sharpness" would be
fully restored.

Those are *your* claims! (In Eric's rendition.)

However you challenged me to support my claim that he
actually said that. Remember? Yo said yourself; âEURoeNo
one who understood what we we trying to talk about would
claim that a JPG conversion is a reversible process.âEUR�
âEUR¦but Floyd did, and Floyd knows what he is talking
about, and he means what he says.

Of course that is a total fabrication on your part. I
said nothing about reversing a JPEG conversion.

I understood him to be saying that inspite of the
losses of a JPEG
conversion, recovery of the original sharpness is possible if the
original sharpening process used a high pass filter. That while saving
as a JPEG will always cause losses, this will not prevent a Gaussian
blur operation from recovering the sharpness of the original image.

Again, that is extremely close but lets not suggest that
the "sharpness of the original image" is *fully*
recovered. In other words "sharpness of the original
image" is not the same as "original sharpness".

Regardless, none of that is what I said.

Regardless of what you understood him to mean, what did
he actually say? I doubt that Floyd would be please with
anybody being so bold as to paraphrase his words. He
does mean what he says doesnâEUR(Tm)t he?

So why do you insist on making absurd claims suggesting
the meaning is other than precisely what is stated!
Your argument on this is a total fabrication on your
part. It's dishonest and lacks integrity.

I certainly donâEUR(Tm)t have the engineering background you
and Floyd have, but I have a solid education in the
sciences

Solid as a pile of sand?

and I have had years of experience in
microbiology and lab work, all of which strangely led me
down another career path solidly entrenched in
investigation. One of the things I have been quite good
at over the last 30+ years is remembering and pinning
down inconstancies in statements. They can be
revealing. So rather than put words in his mouth, let
Floyd's words stand on their own without your
interpretation.

As every criminal trial attorney is aware, a typical
police officer is very good at twisting words to
insinuate guilt where none exists. You *create* the
"inconstancies" to pin down.

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