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HDR Problem

 
 
bodhisoma@gmail.com
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      12-26-2006
Greetings,

Using Photoshop CS 2, having problems with the Merge to HDR function.

I've taken a series of photographs in RAW capture mode. These are
generally -2, -1, 0, +1, +2 EV. When I load these five images into the
function, I get "There is not enough dynamic range in these photos to
construct a useful HDR image."

To be extra clear, these are five *diffierent* RAW files, each a full
EV apart. These are not outputs from the same RAW file. Is it
possible that the range of tonality in my picture is encompased in each
one of the pictures?

Thanks,
Jason

 
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babalooixnay@hotmail.com
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      12-27-2006

http://www.velocityreviews.com/forums/(E-Mail Removed) wrote:
> Greetings,
>
> Using Photoshop CS 2, having problems with the Merge to HDR function.
>
> I've taken a series of photographs in RAW capture mode. These are
> generally -2, -1, 0, +1, +2 EV. When I load these five images into the
> function, I get "There is not enough dynamic range in these photos to
> construct a useful HDR image."
>
> To be extra clear, these are five *diffierent* RAW files, each a full
> EV apart. These are not outputs from the same RAW file. Is it
> possible that the range of tonality in my picture is encompased in each
> one of the pictures?


That sounds like a reasonable range. I generally go even further in
range although +2, 0, and -2 usually give a usable range Did you stay
at the same aperture setting throughout? You are looking for extreme
under and over exposure and I think you'll find that changing aperture
changes depth of field and an ability to not put all the photos in
register. I've found the best way is simply set the camera on manual,
calculate a reasonable exposure then do all of my EV changes with
shutter speed. Are you on a tripod?

It's quite an interesting process although the results can be badly
overdone and strange looking but there is a fantastic ability to
overcome inherent bad lighting that was out of your control and still
come out with a great photo. And with that said there is also the
possibility that what we think of now as being overdone in Dynamic
Range may just become the norm further down the road as we get used to
it

 
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Little Juice Coupe
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      12-27-2006
It should work, unless it just sees that they were once RAW files and
assumes that they all came from the same RAW file. Stupid assumption, but
possible I guess. I know this feature has its share of problems.

Have you tried posting this in the Adobe Forums for Photoshop. There are a
couple of tech people on their from time to time that might be able to shed
some light on the problem.

The only other thing I can suggest is that you export them using the highest
quality setting using the Save For Web feature. Yes, this makes them jpg,
but if you use the least amount of compression possible it might work. Not
because of the compression or file format but because Save For Web strips
everything out of the file including thumbnails and EXIF information. Though
I would think HDR would want the exposure information, but as I said it is
worth a shot.

ljc


<(E-Mail Removed)> wrote in message
news:(E-Mail Removed) oups.com...
>
> (E-Mail Removed) wrote:
>> Greetings,
>>
>> Using Photoshop CS 2, having problems with the Merge to HDR function.
>>
>> I've taken a series of photographs in RAW capture mode. These are
>> generally -2, -1, 0, +1, +2 EV. When I load these five images into the
>> function, I get "There is not enough dynamic range in these photos to
>> construct a useful HDR image."
>>
>> To be extra clear, these are five *diffierent* RAW files, each a full
>> EV apart. These are not outputs from the same RAW file. Is it
>> possible that the range of tonality in my picture is encompased in each
>> one of the pictures?

>
> That sounds like a reasonable range. I generally go even further in
> range although +2, 0, and -2 usually give a usable range Did you stay
> at the same aperture setting throughout? You are looking for extreme
> under and over exposure and I think you'll find that changing aperture
> changes depth of field and an ability to not put all the photos in
> register. I've found the best way is simply set the camera on manual,
> calculate a reasonable exposure then do all of my EV changes with
> shutter speed. Are you on a tripod?
>
> It's quite an interesting process although the results can be badly
> overdone and strange looking but there is a fantastic ability to
> overcome inherent bad lighting that was out of your control and still
> come out with a great photo. And with that said there is also the
> possibility that what we think of now as being overdone in Dynamic
> Range may just become the norm further down the road as we get used to
> it
>



 
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Rich
Guest
Posts: n/a
 
      12-27-2006

(E-Mail Removed) wrote:
> Greetings,
>
> Using Photoshop CS 2, having problems with the Merge to HDR function.
>
> I've taken a series of photographs in RAW capture mode. These are
> generally -2, -1, 0, +1, +2 EV. When I load these five images into the
> function, I get "There is not enough dynamic range in these photos to
> construct a useful HDR image."
>
> To be extra clear, these are five *diffierent* RAW files, each a full
> EV apart. These are not outputs from the same RAW file. Is it
> possible that the range of tonality in my picture is encompased in each
> one of the pictures?
>
> Thanks,
> Jason


I'm curious. How does PS deal with the inevitable blooming or pixel
charge bleedover that happens with +2 exposures? For example, where
you shoot a light source at night and at the longer exposure a near
point source of light ends up 4x the size that it is at a lower
exposure? Unless it somehow erases the bleedover, it must end up in
the final image?

 
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bodhisoma@gmail.com
Guest
Posts: n/a
 
      12-27-2006
(E-Mail Removed) wrote:
>
> That sounds like a reasonable range. I generally go even further in
> range although +2, 0, and -2 usually give a usable range Did you stay
> at the same aperture setting throughout? You are looking for extreme
> under and over exposure and I think you'll find that changing aperture
> changes depth of field and an ability to not put all the photos in
> register. I've found the best way is simply set the camera on manual,
> calculate a reasonable exposure then do all of my EV changes with
> shutter speed. Are you on a tripod?


Yep, only changing the shutter speed. And I am using a tripod.

I think my problem was a screen after the NEF files were merged. It
asked me to *either* designate the EV for each picture *or* to provide
the ISO and shutter speed (and something else, can't remember). I just
left it "as is" previously. When I labeled them -2 through +2 (in a
set of 5) from darkest to lightest, I got an HDR output.

> It's quite an interesting process although the results can be badly
> overdone and strange looking but there is a fantastic ability to
> overcome inherent bad lighting that was out of your control and still
> come out with a great photo. And with that said there is also the
> possibility that what we think of now as being overdone in Dynamic
> Range may just become the norm further down the road as we get used to
> it


I'd be nice if I could just capture seven frames (+/- 3). Maybe
someday.

Thanks for the help.

Jason

 
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