From: Floyd L. Davidson on
"Wilba" <usenet(a)CUTTHISimago.com.au> wrote:
>Floyd L. Davidson wrote:
>> Wilba wrote:
>>> Floyd L. Davidson wrote:
>>>> Wilba wrote:
>>>>> Floyd L. Davidson wrote:
>>>>>> Wilba wrote:
>>>>>>> Floyd L. Davidson wrote:
>>>>>>>> Wilba wrote:
>>>>>>>>> Porte Rouge wrote:
>>>>>>>>>>
>>>>>>>>>> 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.
>>>>>>>>>
>>>>>>>>> Yes, reducing the exposure in Lightroom just puts your histogram
>>>>>>>>> back
>>>>>>>>> to
>>>>>>>>> the left, so that's a waste of time.
>>>>>>>>
>>>>>>>> Yes for the histogram, but it is not a waste of time.
>>>>>>>>
>>>>>>>> Increasing the exposure adds signal, but the noise stays
>>>>>>>> the same. In other words, if you take a shot of an
>>>>>>>> object that is all grey, with nothing approaching
>>>>>>>> "white" at all in the entire scene, you could
>>>>>>>>
>>>>>>>> 1) Expose to produce an histogram that matches
>>>>>>>> the scene, showing all values to be in the
>>>>>>>> middle of the graph. This will produce an
>>>>>>>> accurately exposed JPEG too.
>>>>>>>>
>>>>>>>> or,
>>>>>>>>
>>>>>>>> 2) Expose to produce an histogram with the data
>>>>>>>> pushed so far to the right that it is almost,
>>>>>>>> but not quite, clipping. The JPEG produce
>>>>>>>> will be "overexposed", and instead of grey
>>>>>>>> the scene will be white.
>>>>>>>>
>>>>>>>> But we want an image made from the camera raw data, not
>>>>>>>> the JPEG. And note that with either of the above
>>>>>>>> methods the "noise" in the data will be the same. The
>>>>>>>> Signal to Noise Ratio (SNR) for method #2 will be higher
>>>>>>>> because the signal is higher.
>>>>>>>>
>>>>>>>> The final image is made using the RAW converter, or an
>>>>>>>> image editor like Photoshop after conversion, to reduce
>>>>>>>> the whites down to grey. And the same process will
>>>>>>>> *equally* reduce the noise. Thus the noise in the final
>>>>>>>> image will be *lower* with method 2 than with method 1.
>>>>>>>>
>>>>>>>> Reducing the amount of noise in the final product is
>>>>>>>> probably *not* a waste of time.
>>>>>>>
>>>>>>> You're the only one who has suggested otherwise. This fibre is about
>>>>>>> whether reducing the exposure in post-processing is a good way to
>>>>>>> recover saturation. Please pay attention to the conversation.
>>>>>>
>>>>>> "Recover saturation" means what? Nobody has said any
>>>>>> such thing. *You* need to pay attention.
>>>>>
>>>>>Porte Rouge said (underlines added to emphasise the seminal phrases), "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?"
>>>>>
>>>>>> The statement (quoted above) was made that, "Yes,
>>>>>> reducing the exposure in Lightroom just puts your
>>>>>> histogram back to the left, so that's a waste of time."
>>>>>
>>>>>Right, a precise and appropriate answer to Porte's question.
>>>>
>>>> As I noted in my original response, that is not a correct
>>>> statement. It is *not* a waste of time. It does more than
>>>> "just puts your histogram back".
>>>>
>>>>>> That is not true. It does more than just moving the
>>>>>> "histogram back to the left", and what it does do is
>>>>>> reduce noise, which is not usually a waste of time.
>>>>>
>>>>>I can see I'm going to have to insult you again very soon. :- )
>>>>
>>>> That won't help your problem though...
>>>>
>>>> Here is the part you missed the significance of:
>>>>
>>>> "_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?"
>>>>
>>>> The "obvious fix" clearly states that in terms of
>>>> restoring the color "saturation" (which is actually
>>>> *not* what it is doing), it works. That was *not* the
>>>> question he is asking at all, as you seem to think.
>>>>
>>>> The question was does it do anything else? Why not just
>>>> set the in-camera exposure lower? Does it make any
>>>> difference?
>>>
>>> Ah, I see where you've got it all twisted out of shape.
>>
>> The fact is, I read it correctly and you didn't.
>>
>>>> The correct answer is that yes it does make other differences.
>>>
>>> No-one has ever disputed that. If only it was somehow relevant. :- )
>>
>> You sure argue about it though. Why?
>
>I haven't argued about it at all, neither has anyone else. You're reading
>things that aren't there. We've all been talking about very different
>things. Seriously!

Right! That's why you got so flustered you had to post how many
articles that had *nothing* *but* gratuitous insults????

You do have an extensive set of weasel words...

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd(a)apaflo.com
From: Floyd L. Davidson on
"Wilba" <usenet(a)CUTTHISimago.com.au> wrote:
>Floyd L. Davidson wrote:
>>
>> You need to listen carefully. You *don't* know what
>> your head room is. It changes with different scenes and
>> different lighting, and in particular if you use any
>> type of "auto" for white balance.
>
>What's a method that can be used to measure it?

I've already given you my response to that. It was
something along the lines of find somebody you have not
insulted recently, and ask nicely.

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

>>>>> The correct answer is that yes it does make other differences.
>>>>
>>>> No-one has ever disputed that. If only it was somehow relevant. :- )
>>>
>>> You sure argue about it though. Why?
>>
>> I haven't argued about it at all, neither has anyone else. You're reading
>> things that aren't there. We've all been talking about very different
>> things. Seriously!
>
> Right! That's why you got so flustered you had to post how many
> articles that had *nothing* *but* gratuitous insults????

I did a count ... Zero. I'm not flustered at all, I'm just astounded. Take
it as read from now on that when you project something onto me, and I don't
respond to it, it is denied. I'll only affirm the accurate ones.

> You do have an extensive set of weasel words...

Yeah, I guess it would seem that way if you misunderstand everything I've
said except the insults. :- )


From: Wilba on
Floyd L. Davidson wrote:
> Wilba wrote:
>> Floyd L. Davidson wrote:
>>>
>>> You need to listen carefully. You *don't* know what
>>> your head room is. It changes with different scenes and
>>> different lighting, and in particular if you use any
>>> type of "auto" for white balance.
>>
>> What's a method that can be used to measure it?
>
> I've already given you my response to that. It was
> something along the lines of find somebody you have not
> insulted recently, and ask nicely.

What were you saying about weasel words? :- )

I insult everyone sooner or later (usually when I'm not trying to,
whatever), so that narrows it down ...

OK, to avoid this being my first contribution with *nothing* *but*
gratuitous insults, here's a method.

Set an exposure that looks correct according to ETTR. Shoot. Overexpose by
one increment (e.g. 1/3 step). Shoot. Continue up to say 3 steps over. Open
the raw files in your everyday raw developer. Find the most over-exposed one
from which a image without clipping can be recovered. The over-exposure in
that one is your headroom under those conditions. How's that?


From: Floyd L. Davidson on
"Wilba" <usenet(a)CUTTHISimago.com.au> wrote:
>Floyd L. Davidson wrote:
>> Wilba wrote:
>>> Floyd L. Davidson wrote:
>>>>
>>>> You need to listen carefully. You *don't* know what
>>>> your head room is. It changes with different scenes and
>>>> different lighting, and in particular if you use any
>>>> type of "auto" for white balance.
>>>
>>> What's a method that can be used to measure it?
>>
>> I've already given you my response to that. It was
>> something along the lines of find somebody you have not
>> insulted recently, and ask nicely.
>
>What were you saying about weasel words? :- )
>
>I insult everyone sooner or later (usually when I'm not trying to,
>whatever), so that narrows it down ...
>
>OK, to avoid this being my first contribution with *nothing* *but*
>gratuitous insults, here's a method.
>
>Set an exposure that looks correct according to ETTR. Shoot. Overexpose by
>one increment (e.g. 1/3 step). Shoot. Continue up to say 3 steps over. Open
>the raw files in your everyday raw developer. Find the most over-exposed one
>from which a image without clipping can be recovered. The over-exposure in
>that one is your headroom under those conditions. How's that?

Wrong.

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