Se for usar um único RAW para extrair exposições tenha em
mente que o limite é a latitude da digicam que geralmente é
ruim. Tem que saber os limites para poder fotometrar de acordo
com a situação, prevendo um “HDR.”
Transformar as imagens em algum formato de 16bits como TIFF/PNG
e não JPG de 8bits...
VCs tem que dar uma BOA lida nisto aqui...http://www.hdrsoft.com/support/faq_photomatix.htmlTips & Tricks
›I have a RAW file. Can I make different exposures with it to use in your software? Yes, you can still use Photomatix when you have shot at only one exposure
in RAW mode. And you do not necessarily need to derive several exposures from
your RAW file as explained below. The big advantage of course is that you just
need one image, so no need to use a tripod, no need to remember to auto bracket
and it will also work if the subject is moving.
However, the range of "workable" exposures you can get from a RAW file is
limited. So, it all depends on your scene. If it is a really high contrast scene, then
you are unlikely to match the results you would have with taking the scene under
different exposures that can cover the whole dynamic range. On the other hand,
the scene's dynamic range should not be too low either.
For instance, if your scene
does not have a high contrast and the only problem is that it was not taken at the
right exposure, then Photomatix may be overkill and tools that are specific to
exposure correction may give you better results in that case. There are two techniques for using Photomatix with images derived from a
single RAW file:
• Technique 1: Convert your RAW file into a 16-bit TIFF and apply the Tone
Mapping tool to it (under menu "HDRI"), or the "48-bit Compression" tool.
• Technique 2: Create two or three exposures in your RAW converter and
combine them with the Exposure Blending functions of Photomatix. "Highlights &
Shadows - Auto" is often the most appropriate method in this case.
For good results with the Tone Mapping applied to a single 16-bit file, it is
important to ensure a low noise level. For this, we recommend exposing for the
shadows when taking the RAW image, i.e. to overexpose your shot. Even though
the histogram of your camera may indicate that your highlights will be lost, you
should still be able to recover them during RAW conversion (unless the dynamic
range of your scene is too high, in which case you will need to bracket).
When converting your overexposed RAW file, set an exposure of -1 or -2
depending on how much highlights you want to bring back. You can see two
examples obtained this way here.
Something worth noting here, is that not all RAWs are equals when it comes
to dynamic range. Most digital cameras are using sensors with a depth of 12 bits
but the level of noise may diminish the dynamic range substantially. Moreover,
some camera manufacturers seem to prefer lowering the bit-depth when storing
the sensor data as RAWs (see for instance this article on D70 NEFs).
On the other hand, some high end cameras have sensors with a depth of 14
bits, which means two f-stops more of dynamic range. It is definitely a good idea to
try the Tone Mapping tool of Photomatix on the 16-bit TIFF file derived from the the
RAW data of such cameras. Also, the dynamic range of the RAWs of the Fuji S3 Pro
is higher than RAWs of other DSLRs.
In any case, merging exposures derived from a single RAW should only be
done with the Exposure Blending functions of Photomatix (the ones under the
"Combine" menu). If you want to use the tone mapping tool, then you do not need
to artificially create several exposures (an HDR image created from bracketed
RAWs does not really make sense as explained here). You just need to convert
your RAW into a 16-bit file and then apply the Tone Mapping to it.
