From: Wilba on
Chris Malcolm wrote:
> Wilba wrote:
>>
>> DRS, I really admire your patience and tolerance.
>>
>> As a rule I try not to be _too_ insulting, but in this case I have to
>> say,
>> Floyd, you are ASTONISHINGLY thick and childish for someone who
>> often sounds very intelligent. I can't recall the last time I've seen
>> such a
>> stupendous display of belligerant idiocy. You really are a champ.
>
> It can be very educational arguing with Floyd when he's right. It's a
> tedious and pointless exercise to argue with him when he's wrong.

Mm, the challenge, when your basic assumption is that the other has a valid
point of view and is also trying to understand you, is to tell when
reactivity has overcome rationality. I'm not sure I'm getting any better at
it. :- )


From: Wilba on
John McWilliams wrote:
> Wilba wrote:
>> Paul Furman wrote:
>>> Mike Russell wrote:
>>>>
>>>> Here's something similar that will work on most versions of PS
>>>> http://www.anntorrence.com/blog/2008/02/multiply-and-screen-to-adjust.html
>>> Wow, thanks! Interesting how he ...
>>
>> � Ann Torrence. :- )
>>
>>> ... duplicated the effect with curves and that looks a lot like a gamma
>>> adjustment. Seems like it incorporates the linear-data conversion to
>>> adjusted-for-human-perception idea (if that makes sense).
>>
>> Yeah, very interesting to see. Layer blending modes always seems like
>> black-magic to me, since I don't have a clue what's really going on. I
>> often feel like a monkey with a typewriter with a lot of Photoshop.
>>
>>> "Multiply/Screen"
>>> -storing that away for future use...
>>>
>>> Fascinating to overlay those two files in PS & scroll through the layer
>>> modes. Pick one from the drop-down then use the up/down arrow
>>> keys to browse.
>>
>> Isn't it? I wish I'd thought of that. :- )
>
> IIRC, there's an arrow and key combo that zips you through all the
> blending modes if you're in the right tool.

Yeah, just select the combo-box and arrow down. _Understanding_ what's going
on, rather than just seeing the effect, is another thing altogether.

> There are video tuts just on blending modes, and it's pretty neat stuff.
> They are grouped, the modes, and a tutorial may show what they have
> in common.

It's a matter of priorities for me - hours of work to understand something I
won't retain to do things I don't feel the need to do ..., or do something
else useful and fun. Hmm ... :- )


From: Bob Larter on
Paul Furman wrote:
> OK, this makes sense, the posterizing issue is not really visible in any
> sort of normal exposure. What about Floyd's comment below that the noise
> level remains the same but exposing to the right increases the signal so
> that overwhelms the noise? That seems to tie the two together in a
> comprehensible way.

Look at it this way: Your RAW image will have the same amount of noise,
regardless of the exposure. But exposing to the right will lift the
shadow levels up higher, relative to the noise. When you process the RAW
image on your PC, you'll lower the brightness levels back down, thus
lowering the absolute noise levels with them.
More technically, you're maximising the signal-to-noise ratio.


--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
From: Paul Furman on
John A. wrote:
> On 11 Oct 2009 09:59:27 GMT, Chris Malcolm <cam(a)holyrood.ed.ac.uk>
> wrote:
>
>> In rec.photo.digital.slr-systems Paul Furman <paul-@-edgehill.net> wrote:
>>
>>> What about saturation? Reducing saturation seems to give more detail to
>>> the edges also.
>> That could be a side effect of chromatic aberration. Do you notice it
>> when there's no chromatic aberration?
>
> Or from chroma subsampling if you're working with jpegs.

I don't think either would have much effect. It looks to make as big of
a difference as contrast.

--
Paul Furman
www.edgehill.net
www.baynatives.com

all google groups messages filtered due to spam
From: Floyd L. Davidson on
"Wilba" <usenet(a)CUTTHISimago.com.au> wrote:
>Floyd L. Davidson wrote:
>
>> Neither you nor DRS were even able to analyze a couple of
>> fairly simple histograms;
>
>I decided not to respond to that challenge because it was irrelevant to what

Sure Wilba, sure. In fact, the put up or shut up
challenge simply ended the discussion because nobody
could even come close. They *knew* it was over. No
point repeatedly claiming to understand histograms when
you can't even analyze a simple one!

As the least well informed of just about anyone who got
into the discussion, your posting entire articles with
nothing but insults is just hilariously entertaining.

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd(a)apaflo.com