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one-file HDR

 
 
John McWilliams
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      11-08-2006
Bigma wrote:
> I give my 100% approval to Lubecki and Polhill opinions.


All of them?

It's a good idea to quote enough of what you approve of.

I agree that evening out dynamic range can be a bad thing, but sometimes
it's useful to pull detail out where you couldn't get it otherwise. It
can easily be overdone, but using it doesn't preclude still being
"artistic".

--
john mcwilliams
 
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Richard Polhill
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      11-08-2006
On 2006-11-08 16:52:22 +0000, John McWilliams <(E-Mail Removed)> said:

>
>
> I agree that evening out dynamic range can be a bad thing, but
> sometimes it's useful to pull detail out where you couldn't get it
> otherwise. It can easily be overdone, but using it doesn't preclude
> still being "artistic".


I agree. I'm sure it has its place and saves a lot of farting around
with multiple exposures or compositing that may or may not get the
results. I still refer to the only good application I've seen is church
interiors where you want the interior stone and the backlit stained
glass windows to be exposed perfectly at the same time.

It is a technique that is overhyped, often backed up with such flat
lacklustre examples to put one off considering the technique.

I do wonder just how much exposure latitude is available from a single
slide or negative, however. The implication by HDR evangelists is that
you can overcome the limitation of film dynamic range by using several
shots using an inherently lower dynamic range medium - digital.

Has anyone managed to provide objective examples that demonstrate the
limitations of either medium?
--
invalid = com

 
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Richard Polhill
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      11-08-2006
On 2006-11-08 16:49:08 +0000, Bill Funk <(E-Mail Removed)> said:

>>

>
> I thought HDR was an attempt to make a photo look like what the eye
> sees.
> The eye, with a brain behind it to "process" the image, will "see" a
> higher dynamic range than a camera can.
> But these photos do not look natural at all; certainly not like what
> the eye sees.
> They look more like what old B&W horror films looked like.
> Only in color.


They are pretty foul aren't they. The castle looks like a bad
composite, which I suppose it is in a way. The others look like they've
been taken with a contrast grad filter over the lens, if such a thing
existed.

Would have got better results using dodge and burn.
--
invalid = com

 
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Hebee Jeebes
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      11-08-2006
The reason Photoshop does that is because there is not difference between
the pictures. While the human's may not be able to see all of the data
hidden is shadows and highlights the software can. By taking the same RAW
image and making exposure adjustments to it for 3 or more separate images
they only thing you are doing is fixing it so that the human can see the
data. The software always could that is why Photoshop doesn't allow you to
do HDR from a single image no matter how you adjust it.

That is also why your attempts don't look anything like a true HDR image.

R


"Rutger" <(E-Mail Removed)> wrote in message
news:4551b611$0$1639$(E-Mail Removed)2.nl...
> "Kelpie" <(E-Mail Removed)> schreef in bericht
> news:(E-Mail Removed)...
>>
>> "Rutger" <(E-Mail Removed)> wrote in message
>> news:4550f55e$0$24688$(E-Mail Removed)2.nl...
>>> Today i made some one-file HDR images:
>>> Took a RAW, processed it for under, normal and overexposure and
>>> processed them further for HDR.

>>
>> What software did you use for the post processing?

>
> Photomatix pro, since PS just looks at the Exif-data and sees no
> difference between the pictures.
>
> Rutger
>
>
> --
> http://www.flickr.com/photos/zwaarddrager/sets
>



 
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Hebee Jeebes
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Posts: n/a
 
      11-08-2006
If that was the case bill why do 99% of HDR images look fake. The human eye
didn't see the scene fake? Most HDR are just horrible, these probably more
so since their weren't real HDR images to start with.

R


"Bill Funk" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On Tue, 7 Nov 2006 22:09:21 +0100, "Rutger" <(E-Mail Removed)> wrote:
>
>>Today i made some one-file HDR images:
>>Took a RAW, processed it for under, normal and overexposure and processed
>>them further for HDR.
>>
>>http://www.flickr.com/photos/zwaardd...440531/detail/
>>
>>
>>Rutger

>
> I thought HDR was an attempt to make a photo look like what the eye
> sees.
> The eye, with a brain behind it to "process" the image, will "see" a
> higher dynamic range than a camera can.
> But these photos do not look natural at all; certainly not like what
> the eye sees.
> They look more like what old B&W horror films looked like.
> Only in color.
> --
> Bill Funk
> replace "g" with "a"



 
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Rutger
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Posts: n/a
 
      11-08-2006
"Bill Funk" <(E-Mail Removed)> schreef in bericht
news:(E-Mail Removed)...
> On Tue, 7 Nov 2006 22:09:21 +0100, "Rutger" <(E-Mail Removed)> wrote:
>
>>Today i made some one-file HDR images:
>>Took a RAW, processed it for under, normal and overexposure and processed
>>them further for HDR.
>>
>>http://www.flickr.com/photos/zwaardd...440531/detail/
>>
>>
>>Rutger

>
> I thought HDR was an attempt to make a photo look like what the eye
> sees.


That's what i tried: the skies were actually very dark overthere.

Rutger


--
http://www.flickr.com/photos/zwaarddrager/sets


 
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Bill Funk
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      11-08-2006
On Wed, 8 Nov 2006 10:16:36 -0800, "Hebee Jeebes" <(E-Mail Removed)>
wrote:
>
>"Bill Funk" <(E-Mail Removed)> wrote in message
>news:(E-Mail Removed).. .
>> On Tue, 7 Nov 2006 22:09:21 +0100, "Rutger" <(E-Mail Removed)> wrote:
>>
>>>Today i made some one-file HDR images:
>>>Took a RAW, processed it for under, normal and overexposure and processed
>>>them further for HDR.
>>>
>>>http://www.flickr.com/photos/zwaardd...440531/detail/
>>>
>>>
>>>Rutger

>>
>> I thought HDR was an attempt to make a photo look like what the eye
>> sees.
>> The eye, with a brain behind it to "process" the image, will "see" a
>> higher dynamic range than a camera can.
>> But these photos do not look natural at all; certainly not like what
>> the eye sees.
>> They look more like what old B&W horror films looked like.
>> Only in color.
>> --
>> Bill Funk
>> replace "g" with "a"

>
>If that was the case bill why do 99% of HDR images look fake. The human eye
>didn't see the scene fake? Most HDR are just horrible, these probably more
>so since their weren't real HDR images to start with.
>
>R


As I said, the eye has a computer behind it; so, no, the eye didn't
see the scene as fake.
--
Bill Funk
replace "g" with "a"
 
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Roger N. Clark (change username to rnclark)
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Posts: n/a
 
      11-09-2006
Bill Funk wrote:
> On Wed, 8 Nov 2006 10:16:36 -0800, "Hebee Jeebes" <(E-Mail Removed)>
> wrote:
>
>>"Bill Funk" <(E-Mail Removed)> wrote in message
>>news:(E-Mail Removed). ..
>>
>>>On Tue, 7 Nov 2006 22:09:21 +0100, "Rutger" <(E-Mail Removed)> wrote:
>>>
>>>>Today i made some one-file HDR images:
>>>>Took a RAW, processed it for under, normal and overexposure and processed
>>>>them further for HDR.
>>>>
>>>>http://www.flickr.com/photos/zwaardd...440531/detail/
>>>>
>>>>Rutger
>>>
>>>I thought HDR was an attempt to make a photo look like what the eye
>>>sees.
>>>The eye, with a brain behind it to "process" the image, will "see" a
>>>higher dynamic range than a camera can.
>>>But these photos do not look natural at all; certainly not like what
>>>the eye sees.
>>>They look more like what old B&W horror films looked like.
>>>Only in color.
>>>--
>>>Bill Funk
>>>replace "g" with "a"

>>
>>If that was the case bill why do 99% of HDR images look fake. The human eye
>>didn't see the scene fake? Most HDR are just horrible, these probably more
>>so since their weren't real HDR images to start with.
>>
>>R

>
> As I said, the eye has a computer behind it; so, no, the eye didn't
> see the scene as fake.


While it is tru the eye has an effective dynamic range much
greater than any camera, and an HDR image can record that range,
the problem then becomes processing the data to compress that
range into a smaller dynamic range that any output device is capable
of showing, whether CRT, LCD, paper, Plasma, etc. It is that
processing step that can mangle the data to make the image look
fake.

Roger
 
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Ole Larsen
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Posts: n/a
 
      11-09-2006
Richard Polhill skrev:
> On 2006-11-08 16:52:22 +0000, John McWilliams <(E-Mail Removed)> said:
>
>>
>>
>> I agree that evening out dynamic range can be a bad thing, but
>> sometimes it's useful to pull detail out where you couldn't get it
>> otherwise. It can easily be overdone, but using it doesn't preclude
>> still being "artistic".

>
> I agree. I'm sure it has its place and saves a lot of farting around
> with multiple exposures or compositing that may or may not get the
> results. I still refer to the only good application I've seen is church
> interiors where you want the interior stone and the backlit stained
> glass windows to be exposed perfectly at the same time.
>
> It is a technique that is overhyped, often backed up with such flat
> lacklustre examples to put one off considering the technique.
>
> I do wonder just how much exposure latitude is available from a single
> slide or negative, however. The implication by HDR evangelists is that
> you can overcome the limitation of film dynamic range by using several
> shots using an inherently lower dynamic range medium - digital.
>
> Has anyone managed to provide objective examples that demonstrate the
> limitations of either medium?


It seems to me that there is some confusion about the idea behind HDR.

As I understand it, the idea is to capture a dynamic range otherwise too
large to capture and _compress_ it to make it possible to reproduce,
including the othewise lost extremes. Doing this will naturally cause
flattening of some areas, likely the middletones. To those of us who
have used chemicals and the zone system, this is obvious.

Rutgers approach is tempting, but there is no such thing as a free
lunch, and HDR often calls for a 4-5 steps difference in exposure in
order to catch both highlights and shadows - and you cant tune that much
from one single exposure in the raw converter. In fact, I think what you
can get with Rutgers methods, you can get without.

--
Med venlig hilsen, Ole Larsen.
New Images And Design, oct. 2006
http://Olelarsen.eu/
 
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bugbear
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Posts: n/a
 
      11-10-2006
http://www.velocityreviews.com/forums/(E-Mail Removed) wrote:
> Rutger wrote:
>
>>Today i made some one-file HDR images:
>>Took a RAW, processed it for under, normal and overexposure and processed
>>them further for HDR.
>>
>>http://www.flickr.com/photos/zwaardd...440531/detail/

>
>
> Sorry, but I just don't "get" HDR. Most of those pictures look pretty
> bad to me, especially the one with all the tree branches. I think all
> of them would look much better in a single exposure.


I suppose it's a jargon thing.

An HDR file is "truly" HDR - high dynamic range.

But what you see on the 'net (e.g. flickR) is
a *normal* image (e.g. JPEG) derived from an HDR
file.

The range of the HDR is mapped
(normally by compression into the
range of the web (JPEG) file.

Of course, this does mean that the use of HDR
gives very fine control over the final exposed
image, since shadows and highlights are
perfectly exposed (in the HDR format).

It also means that HDR files can be used
as an "ideal" version of the image in processing
(e.g. ray-tracing, which is where they started).

BugBear
 
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