From: Floyd L. Davidson on
Paul Furman <paul-@-edgehill.net> wrote:
>Floyd L. Davidson wrote:
>> Doug McDonald <mcdonald(a)NoSpAmscs.uiuc.edu> wrote:
>>> Floyd L. Davidson wrote:
>>>
>>>> But regardless of that, the cited URL above from
>>>> luminous-landscape is *not* full of good stuff. They
>>>> miss the point entirely, and provide nothing that is
>>>> actually useful! All that changing in-camera contrast
>>>> does is compress/uncompress the histograms idea of
>>>> middle gray. It does not change where the highlights
>>>> fall, and thus does not change what you would set for
>>>> the exposure. (Does anyone ever look at the shape of an
>>>> in-camera histogram and make adjustments as a result?
>>>> It's a meaningless excercise, which will not change the
>>>> camera raw data. The shape of a post processing
>>>> histogram is very useful, but not an in-camera
>>>> histogram.)
>>>>
>>> What you say is wrong for the Canon 30D. The histogram does
>>> not change the raw data stored by the camera. But the camera setting DOES
>>> change the camera displayed histogram. IF you set the camera "comtrast"
>>> setting high, the highlights in the histogram get pushed way up
>>> and are indeed useless for setting exposure. Ii you set it low,
>>> at -3 or -4, the histogram displayed by the camera agrees quite nicely
>>> with how close you are getting to clipping.
>> The brightest part will still show at *exactly* the
>> same
>> place.
>
>Maybe for contrast (though I doubt it) but WB makes a big difference. I
>just tested at 25K & 100K, the highlights are completely different. I'm
>looking at split RGB histograms btw.

That is exactly the point I *am* making. WB changes the
histogram in a useful way. The Luminous-Landscape
article did not talk about WB at all. They discussed
changing the camera's setting for contrast, and that
simply does *nothing* useful for the histogram/exposure
issue.

And if you doubt that the contrast setting will not change
the histogram as stated, *try* *it*. I gave an step by
step description of a very easy way to show exactly what
does and does not happen. Why argue from supposition when
you could actually learn something about photography...

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd(a)apaflo.com
From: Doug McDonald on
Charles wrote:
>
>
> I continue to believe that exposing to the right is perpetuated by folks
> with limited experience and knowledge. They are perhaps into the dark parts
> of scenes and don't understand dynamic range. Many of us are more greedy
> and want details at both ends of the luminosity range.
>
> Hey, blow those high-lites out! If that is the intended message of a given
> scene, go for it. I don't care for over-exposed shots ... they are just not
> my thing. I have seen some high-key shots that were attractive and
> effective and do appreciate the skill and art of the photographers who can
> pull that off.
>
> Specular high-lites might deserve to be blown out. Not the point of my
> response. I'll just say it one more time and then go away ... if it is
> clipped (by a sharp knee response curve ... due to sensor saturation or A/D
> saturation or any saturation link in the chain) it is GONE!
>


Again, you simply don't understand.

Let me explain. Say you are doing a landscape of a very
cloudy scene, with not a trace of sun visible, with high
level clouds blocking the sun, so it does not shine on lower
level clouds. The contrast in the sky is still moderately
high. The low key lighting also makes contrast in the
land part of the scene low. The whole affair is low contrast.

If you expose by TTL light meter, normally, it will expose
so that the average of the scene is 18% gray. The highlights,
that is, the brightest clouds, will not be clipped, in fact
they will be well below that. So you expose to the right so that
the brightest clouds are just below clipping. This gets more
photons, ergo, better S/N.

Now remove the high level clouds. The sun is shining on the
lower level clouds and is very, very, very bright. But the
foreground is in shade! You want to not clip the clouds.
The TTL meter will likely want to clip them. So you
are careful and expose to the right to avoid clipping the
clouds.

Now a little bit of sun shines of the foreground, on
a waterfall. If you use the same exposure as the paragraph
above, the specular highlights on the water will clip.
You may very well actually WANT that to happen, so you
are careful to let it.


You ALWAYS want to expose to the right, given enough light that
you don't need a too-long exposure and blurring. Indeed,
of course, you may want to clip specular highlights.

The idea is that this is the correct way, the photographer
simply has to understand how to get it right.

The only time you don't want to expose to the right is
if you are already at ISO 1600 or 3200 and still there
is too little light to avoid blurring if you do.

Doug McDonald
From: abo mahab on
Keys to Happiness

Happiness is the only goal on earth that all people without exception
are seeking to attain. Believers and unbelievers alike seek to be
happy, but each party is using different methods.

However, only believers can achieve genuine happiness. All forms of
happiness attained without a firm belief in God, the Almighty, are
mere illusions.

The following are tips for the attainment of happiness:

1. Know that if you do not live within the scope of today, your
thoughts will be scattered, your affairs will become confused, and
your anxiety will increase. These realities are explained in the
following hadith:

“When you are in the evening, do not expect to see themorning, and
when you are in the morning, do not expect to see the
evening.” (Saheeh Al-Bukhari)

2. Forget the past and all that it contained, focus on the present.

3. Do not completely preoccupy yourself with the future and then
discard the present. Be balanced in life, prepare yourself adequately
for all situations.

4. Do not be shaken by criticism; instead, be firm. Be sure that in
proportion to your worth, the level of people's criticism rises. Also,
make good use of criticism in discovering your shortcomings and
faults, and let it drive you toward self-improvement.

5. Have complete faith in God and perform good deeds; these are the
ingredients that makeup a good and happy life.

6. If you desire peace, tranquility, and comfort, you can find it all
in the remembrance of God.

7. You should know with certainty that everything that happens, occurs
in accordance with the divine decree.

8. Do not expect gratitude from anyone.

9. Train yourself to be prepared for the worst possibility.

10. Perhaps what has happened is in your best interest, even though
you may not comprehend how that can be so.

11. Everything that is decreed for the believer is the best for him.

12. Enumerate the blessings of God and be thankful for them.

13. Remember that you are better off than many others.

14. Relief comes from one hour to the next. Indeed, with each
difficulty there is relief.

15. In both times of hardship and ease, one should turn to
supplication and prayer, either patiently contented or thankful.

16. Calamities should strengthen your heart and reshape your outlook
in a positive way.

17. Do not let trivialities be the cause of your destruction.

18. Always remember that your God is Oft-Forgiving.

19. Assume an easy-going attitude and avoid anger.

20. Life is bread, water, and shade; so do not be perturbed by a lack
of any other material thing.

“And in the heaven is your providence and that which you are
promised.” (Quran 51:22)

21. A daunting evil that seemingly will happen usually never occurs.

22. Look at those who have more afflictions and be grateful that you
have less.

23. Bear in mind the fact that God loves those who endure trials with
steadfastness, so seek to be one of them.

24. Constantly repeat those supplications that the Prophet (may God
praise him) taught us to say during times of hardship.

25. Work hard at something that is productive, and cast off idleness.

26. Do not spread rumors and do not listen to them. If you hear a
rumor inadvertently, do not believe it.

27. Know that your malice and your striving to seek revenge are much
more harmful to your health than they are to your antagonist.

28. The hardships that befall you atone for your sins, if you endure
with patience.

Source::: www.islamreligion.com
From: Paul Furman on
mike wrote:
> In article <hadpc1$8up$1(a)news.eternal-september.org>,
> charlesschuler(a)comcast.net says...
>> So, expose to the right if you can afford lost high-lites ... and I do mean
>> to emphasize LOST. Like a hair-cut, clipped is gone.
>>
> But unlike a hair-cut it never grows back. More of an amputation
> methinks...

http://www.telegraph.co.uk/news/newstopics/howaboutthat/6266097/Pensioner-grows-new-skull.html

-just kidding but 'never say never' <g>
From: John Sheehy on
Porte Rouge <porterougeman(a)gmail.com> wrote in news:eaf6a46b-3ba3-4ba1-
9999-206c3d903904(a)d4g2000vbm.googlegroups.com:

> I set my exposure to slide the histogram to the right, without clipping
> ( when I have time), to capture the most tonal levels . So, now when I
> am editing the photos they are over exposed(not clipped). A sunrise is
> a good example. The deep colors are washed out. The obvious fix(to me
> anyway) in Lightroom or CS4 is to reduce the exposure. Now my question
> is, by reducing exposure in post, am I just ending up in the same place
> (histogram to the left) as if I had just ignored the histogram when I
> was shooting and set the exposure to properly expose the image using
> my light meter? I guess in short I am asking if Lightroom or CS4 loses
> tonal values when you reduce exposure in editing.

They're not really over-exposed, they have simply put your highlights on a
tone curve which makes the colors look pale.

The whole point of you "exposing to the right" is to increase the signal-
to-noise ratio. The "number of tones" explanation often given is
incorrect. All digital cameras have too much noise at all tones to be
limited by numbers of tones, at least in the RAW data. The number of tones
in your output are unrelated to the number of tones in the RAW exposure;
you do not lose all you've gained when the software darkens the image.