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Re: I Miss my Viewfinder !

 
 
Wolfgang Weisselberg
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      06-03-2011
Mxsmanic <(E-Mail Removed)> wrote:

> The point is that you don't need infinite power or bandwidth to obtain
> infinite capacity. All you need is non-zero power, non-zero bandwidth, and
> zero noise.


Where can one find zero noise? In digital?

-Wolfgang
 
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Wolfgang Weisselberg
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      06-03-2011
Mxsmanic <(E-Mail Removed)> wrote:
> David Dyer-Bennet writes:


>> No, undefined; division by zero is undefined.


> Only in grade school. Division by zero does not yield a number, it yields
> infinity. So it _is_ defined, but not as a number.


That is not true. In other words, you didn't listen in
school. Take

x² - 1
------
x - 1

and solve for x = 1. [1] That's a division by zero, but the
result is not infinity!

-Wolfgang

[1] calculate the limes for x -> 1
 
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nospam
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      06-03-2011
In article <(E-Mail Removed)>, Mxsmanic
<(E-Mail Removed)> wrote:

> > > Reversing the changes is different, and many changes cannot be reversed,
> > > because they destroy information.

> >
> > they can when done non-destructively.

>
> That's more than a little self-evident.


apparently not, based on what you write below:

> But many changes cannot be done
> non-destructively. If information is lost, it's lost; it's not an option that
> one can take or leave.


they all can be done non-destructively.

> If you blur an image, for example, you lose information permanently, and there
> is no way to blur an image without doing that.


yes there is. i can easily go back and change the amount of blur, even
remove it entirely, while leaving all other changes in place.

the key is *how* it's done. non-destructive workflow is obviously a new
concept to you (as are a lot of things, it seems).
 
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nospam
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      06-03-2011
In article <(E-Mail Removed)>, Mxsmanic
<(E-Mail Removed)> wrote:

> Most of my posts are written to elicit responses that illustrate just how
> little people actually know.


and it's doing exactly that, about you.
 
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nospam
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      06-03-2011
In article <(E-Mail Removed)>, Mxsmanic
<(E-Mail Removed)> wrote:

> > They know it is worse due to intensity and of course the total number
> > of flashes will be quite high the more valuable or famous a picture is.

>
> But it's not worse.
>
> If you take a picture with flash at 1/250 second, and the same picture without
> flash would take 1 second, then the total energy of the flash is no greater
> than that of 1 second of ambient light. Only the total energy matters. Whether
> it comes as a flash or as a one-second duration of dimmer light does not
> matter. That's what the studies show.


which studies are those? cite them.

let's do a study. how about you point a flash at your eyes and fire it
a bunch of times. do that for hours on end. let's see just how much
damage occurs.

> Thus, each flash is worth perhaps an eighth of a second of natural light. And
> the natural light is always present, so it actually does a lot more damage
> than flash does.


except that the flash is in addition to existing light.

also, flash annoys other patrons. i'd hate to visit a museum with
snap-happy tourists where a flash goes off every few seconds. ugh.
 
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nospam
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      06-03-2011
In article <(E-Mail Removed)>, Mxsmanic
<(E-Mail Removed)> wrote:

> > actually it is worse, because flashes can emit a lot of infrared &
> > ultraviolet light.

>
> No, it isn't worse, and natural light contains a ton of IR and UV.


you've measured the bulbs inside a museum?
 
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Wolfgang Weisselberg
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      06-03-2011
Martin Brown <|||newspam|||@nezumi.demon.co.uk> wrote:
> On 31/05/2011 19:09, Wolfgang Weisselberg wrote:
>> Mxsmanic<(E-Mail Removed)> wrote:
>>> Wolfgang Weisselberg writes:


>>>> digital projector.
>>>> - no tangible endpoint (image)


>>> The projector is an analog device, not a digital device.


>> Each pixel is only on or off at any time.


> Incorrect. See for example:
> http://en.wikipedia.org/wiki/Light_valve


Yes, a DMD.

>> Sounds not very analog. Feel free to explain how this is
>> analog.


> Each pixel is capable of taking on a range of shades depending on the
> signal.


Actually, each pixel is either on or off (or in transition).
The shades are just an illusion of your slow, slow eye.

> The signal paths are digital but the light out is analogue.


Hmmm?

>>>> Worse even: projector that uses coloured light beams (lasers?) to
>>>> paint the image column by column, row by row. There is no image
>>>> at any point outside the eye of the observer.


>>> Nevertheless, the projector is an analog device.


>> How so?


> The brightness of the light in the raster is being modulated as the
> laser scans the picture.


I was thinking of a much simpler (earlier) model: laser on,
laser off, nothing in between. One brightness, unless you
overscan.

> Persistence of vision does the rest.


POV doesn't turn digital into analog, it's just a typical
human shortcoming.

-Wolfgang
 
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Wolfgang Weisselberg
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      06-03-2011
Mxsmanic <(E-Mail Removed)> wrote:
> Wolfgang Weisselberg writes:


>> Each pixel is only on or off at any time.
>> Sounds not very analog.


> Each pixel tends to be either well above a certain threshold in brightness, or
> well below. But it's not just on or off.


It's either receiving light from the projector or it isn't.
Stray light from your torchlight doesn't count.

>> Feel free to explain how this is
>> analog.


> Done. See above.


Not good enough.

>> Waves are physical, then?


> Sometimes.


And I assume a laser projector, with only on and off stages,
is digital, since you don't comment on it.

-Wolfgang
 
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Wolfgang Weisselberg
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      06-03-2011
Eric Stevens <(E-Mail Removed)> wrote:

> I could also say "when you view it at a distance it all blurs into a
> continuous display so its analog" but I won't.



Your insufficient vision isn't my problem. :->

-Wolfgang
 
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PeterN
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      06-03-2011
On 6/3/2011 12:20 AM, nospam wrote:

>
> although non-destructive in photoshop can be done, it's not designed
> for it and is more of a pain in the ass than useful.



Doing your edits on layers is totally non-destructive.

Is is really quite easy.


--
Peter
 
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