Post-Processing RAW vs Post-Processing TIFF

Can you get similar results from post-processing TIFF to those you'd
get from PPing RAW?

And what about JPEG?

 

Dunno for sure m8

But if the stuff I have gleamed is robust then
RAW - is really sensor data with minimal signal processing, is sensor and
camera brand dependent

TIFF - not quite as spot on as RAW as it has (obviously to get into format)
some signal processing

JPEG - the most highly signal processed of the bunch (look for superfine,
fine, medium and low quality declarations in the camera spec)

Aerticeus

 

Nope. Process a RAW and see all the options. Some are: you can adjust white
balance, 16-bit, Size, lots more. Raw gives you more stops of
information....so you are less likely to block up the highlights and
shadows.

 

In message <>,

16-bit TIFF will posterize the levels in the highlights. This is not
visible immediately, but may become visible with some processing.

8-bit TIFF will posterize the highlights much more than 16-bit, and will
posterize the midtones and brighter shadows as well.

JPEG has the same issues as 8-bit TIFF, plus the issues of compression
artifacts, which may be exaggerated after some processing, even if
compression is low.

As luck would have it, programs don't work with the RAW data directly,
so you usually have to settle for a 16-bit TIFF or PSD format if you
want to save your work for optimum future editing.
--

 

In message <>, I,

I forgot to mention; all of these conversion formats are also capable of
losing highlights captured in the RAW file.
--

 

..

Well...you adjust to get those highlights down into a usable range before
you convert from RAW.

 

In message <[email protected]>,

Yes but you have to know that. You'd be surprised how many people think
that highlights blown in the default conversion were never captured.
--

 

Think of cooking a nice dinner.

RAW: You're at the grocery store and can choose or alter any of the
ingredients in the recipe.

TIFF: The dinner is in the oven. You may still be able to make a few changes.

JPG: The dinner is cooked. About all you can do now is add salt.

 

Sublime!

Aerticeus

 

You seem to have the uncanny nack of grasping the obvious. ^5

 

If you use TIFF the demosaicing is done in your camera, but if you use
RAW it is done in your computer. Since your computer has a more
powerful processor, you can employ more sophisticated demosaicing
algorithms with RAW. TIFF files are also larger than RAW files because
it contains interpolated data generated by the demosaicing algorithm.

The second issue relates to bit-depth. Sensor data is 12 to 14 bits
which is properly captured by the RAW format. 8 bit formats such as
JPEG and 8 bit TIFF lose some bit depth. 16 bit TIFF should be fine in
this respect.

Regards,
Tripurari

 

Hi Tripuari

I woder if you have insights about bit compression?

I see in some EXIF details that some shots have 3 bit compression others
have 4, 5 or 8 bit compression

Any clues?

Aerticeus

 

No clues, unfortunately.

-Tripurari

 

No, in both cases. The RAW file really has more information in it.

If the brightness range of the scene doesn't exceed the capability of
the camera to represent in 24 bits, and if you nail the exposure (and
don't need significant adjustments to blacks or whites), then it
probably doesn't matter. But in nearly every other case, there's
significant benefit to using RAW.

I mostly don't anyway, it's enough more trouble and slower and much
more space on my cards; so I only use it for serious photos that are
worth the trouble, and where I anticipate needing it.

 

Speaking of TIFF, why don't more cameras offer a TIFF option for
saving files to the flash card? RAW takes up SO much space, and JPEG
ruins the picture. Wouldn't TIFF be a great compromise?

-Joel

 

In the cameras that I own that do both RAW and TIF the TIF files are MUCH
bigger files than the RAW files.

Perhaps the firmware for COMPRESSED tif files is prohibitive.

 

Nope, on my D100, which offers both, TIFF files are not only BIGGER than
RAW, they take FOREVER to save (has to convert first).

Tom

 

Speaking of TIFF, why don't more cameras offer a TIFF option for

Yes, it would have to be compressed TIFF. Perhaps it takes too long
to create a compressed TIFF file? But if that's the bottleneck, how
about a camera that saves RAW, and then converts from RAW to TIFF in
the background, that is, when the camera isn't doing anything else
(like taking pictures)?

-Joel

 

Thats kind of like making a camera thats also a toaster...not much call for
it I'de think.

 

In message <SoPId.1168$>,

TIFFs are larger than RAWs; even 8-bit TIFFs are larger than RAWs.

High-quality JPEG is about 0.4 bytes per pixel.

8-bit TIFF is 3 bytes per pixel uncompressed, and down to about half
that, compressed, in a best-case scenario (blue sky at ISO 100).

16-bit TIFF is double the 8-bit, and doesn't compress as well unless the
image is very dark.

RAW is about 1 byte per pixel, just a little more than twice the size of
a high-quality JPEG.
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