Still confused about RAW & TIF

Scott W wrote:
Raphael Bustin wrote:
On Sat, 2 Dec 2006 12:11:13 -0800, "Little Juice Coupe"
wrote:

There is more to data loss than just the compression in the file format.
Most programs that let you edit RAW images do it in a non-destructive way.
Meaning you always have the original RAW image. TIF is not that way. While
some programs like Adobe Lightroom let you edit TIFs and JPGs
non-destructively many do not. The first time you run levels or curves or
something on a TIF image you have data loss. Not so with Raw.

The only thing unique about RAW in this context is that
it's a read-only file format.

But many raw converters allow you to save one or more setting for a
given raw file. The effect is that I can set my adjustments as to how
the file will convert and then go back and shift these setting without
any loss. As an example I might have all my WB set the way I want it
but then decide to adjust the exposure of one image, I can do this
without affecting the underlying data. I can do much of the same thing
saving as PSD files and using adjustment layers, but then these file
are much larger then the rather compact raw format.

One of the less publicised features of Lightroom is that the above
applies to JPEGs as well as RAW or TIFF files (and PSD). I don't know
any others that allow editing of jpegs non-destructively- does anyone?
PLEASE put reply below this to keep the continuity.

--
John McWilliams

In article ,
Richard DeLuca wrote:

Hi,

I've only recently using digital, so please pardon my ignorance.
If shooting in RAW or TIF rather than jpeg, can I still manipulate
images afterwards? And without information loss?

Here's what I'd like to accomplish:
Highest image quality so I can take the occasional image to my local
photography shop for them to make 8X10 to 11X17 prints. But I'd like to
do the noise reduction, cropping and other enhancements myself.

Any suggestions appreciated............:-)

I'm still digesting all your responses, but I really do appreciate the
help; this a a great newsgroup. Shot my first RAW images at Rockefeller
Center yesterday.

Also, if I understand what has been said by others using Lightroom Lightroom
allows you to export your images (including JPG and TIF) as a DNG which
would make it Raw. Now not in the true sense of the word since neither JPG
or TIF contain anywhere close to the amount of data a real Raw file has but
it does show that Raw files at least DNG ones are not read only.

LJC


"Raphael Bustin" wrote in message
...
On Sat, 2 Dec 2006 12:11:13 -0800, "Little Juice Coupe"
wrote:

There is more to data loss than just the compression in the file format.
Most programs that let you edit RAW images do it in a non-destructive way.
Meaning you always have the original RAW image. TIF is not that way. While
some programs like Adobe Lightroom let you edit TIFs and JPGs
non-destructively many do not. The first time you run levels or curves or
something on a TIF image you have data loss. Not so with Raw.


The only thing unique about RAW in this context is that
it's a read-only file format.

AFAIK, no program saves a file in RAW format. RAW
can only be created in a digital camera, and only really
makes sense for images created with Bayer sensors.

[Capturing RAW in a film scanner makes very little
sense, IMO.]

If you edit a TIF file, and save the edits to a new file
name, there's no loss whatsoever in the original.


rafe b
www.terrapinphoto.com

Little Juice Coupe wrote:
Also, if I understand what has been said by others using Lightroom Lightroom
allows you to export your images (including JPG and TIF) as a DNG which
would make it Raw. Now not in the true sense of the word since neither JPG
or TIF contain anywhere close to the amount of data a real Raw file has but
it does show that Raw files at least DNG ones are not read only.

What are you getting at? And could you not top post??

--
lsmft

What are you getting at and you can you not top post! Having to sift through
all of the other crap in a post trying to find the reply is bull!

LJC

"John McWilliams" wrote in message
...
Little Juice Coupe wrote:
Also, if I understand what has been said by others using Lightroom
Lightroom allows you to export your images (including JPG and TIF) as a
DNG which would make it Raw. Now not in the true sense of the word since
neither JPG or TIF contain anywhere close to the amount of data a real
Raw file has but it does show that Raw files at least DNG ones are not
read only.

What are you getting at? And could you not top post??

--
lsmft

Little Juice Coupe wrote:
The advantages of Raw of Tiff go much further than just no compression loss.
There are a lot more data in the Raw file than in the Tiff file. The only
thing the Tiff file gives you us no lossy compression like JPG. Otherwise it
is the same camera interpolated image. Meaning all of the cameras in camera
processing has been done to the image, noise reduction, sharpness, white
balance, etc.


There is not a lot more data in the RAW over the TIFF file. The data in the
RAW file is linear in nature, which the TIFF file is not. Thus, in the RAW
file, 1/2 of all the information in the file is in the top stop of exposure.
In short, this means that you should attempt to shoot as exposed as possible
without clipping; then, adjust exposure to what was desired during post
processing. This assures the maximum amount of detail in your final viewable
image.

The Raw file is the Raw data from the cameras sensor and in general doesn't
have any of the image camera processing done to it. Which means you can
change white balance after the fact without loosing image data, etc.


Changing these settings are just metadata values of the RAW file [like
changing the name ... it doesn't affect the actual image data] and these
values are applied during conversion to RGB (or whatever).

Raw also because of the large amount of data that is available over the
bitmap formats of Tiff or JPG allows you to recover shadow and highlight
data that you couldn't do with TIFF or JPG without causing other problems
like lot of ugly noise in the shadows.

Nothing to do with a larger amount of data [or information]. See my comment
above.

--
Thomas T. Veldhouse
Key Fingerprint: D281 77A5 63EE 82C5 5E68 00E4 7868 0ADC 4EFB 39F0

Little Juice Coupe wrote:
Also, if I understand what has been said by others using Lightroom Lightroom
allows you to export your images (including JPG and TIF) as a DNG which
would make it Raw. Now not in the true sense of the word since neither JPG
or TIF contain anywhere close to the amount of data a real Raw file has but
it does show that Raw files at least DNG ones are not read only.


Your above statement isn't correct. There is no way to know which has more
information based upon file format. Equal sized uncompressed TIFF and RAW
with the same bit depth should be similarily sized. The difference is in what
the data is that each file contains. RAW contains raw linear data captured
by the sensor and TIFF contains RGB data, which is non-linear.

The key difference to remember is that with RAW you are working with linear
data and with TIFF (or JPEG) you are not.

--
Thomas T. Veldhouse
Key Fingerprint: D281 77A5 63EE 82C5 5E68 00E4 7868 0ADC 4EFB 39F0

Little Juice Coupe wrote:
What are you getting at and you can you not top post! Having to sift through
all of the other crap in a post trying to find the reply is bull!

LJC


Of course, the real reason you top post is because you use Outlook Express and
it is hard to post "correctly" in that program.

Take a look at this little add-in that will allow you to do it should you feel
motivated.

http://home.in.tum.de/~jain/software/oe-quotefix/

--
Thomas T. Veldhouse
Key Fingerprint: D281 77A5 63EE 82C5 5E68 00E4 7868 0ADC 4EFB 39F0

Thomas T. Veldhouse wrote:
Little Juice Coupe wrote:
Also, if I understand what has been said by others using Lightroom Lightroom
allows you to export your images (including JPG and TIF) as a DNG which
would make it Raw. Now not in the true sense of the word since neither JPG
or TIF contain anywhere close to the amount of data a real Raw file has but
it does show that Raw files at least DNG ones are not read only.


Your above statement isn't correct. There is no way to know which has more
information based upon file format. Equal sized uncompressed TIFF and RAW
with the same bit depth should be similarily sized.

The raw filewill me much smaller since its format is much more
efficient. Take a 8 MP camera, the in the raw file there are 8,000,000
pixels each of which needs only 12 bits of data, therefore and
uncompressed raw file should come in right about 12 MB, with lossless
compression this shrinks to between 8 to 10MB. A tiff file from this
same camera will have three colors / pixel (note the raw file only has
one per pixel) and it will use 16 bits / color or 48 bits per pixel
compared to 12. When I convert to 48 bit tiff files the resulting file
is right around 48 MB in size, which is why I don't like to keep the
tiff fills around.

Scott

"Thomas T. Veldhouse" wrote:
Little Juice Coupe wrote:
The Raw file is the Raw data from the cameras sensor and in general doesn't
have any of the image camera processing done to it. Which means you can
change white balance after the fact without loosing image data, etc.

Changing these settings are just metadata values of the RAW file [like
changing the name ... it doesn't affect the actual image data] and these
values are applied during conversion to RGB (or whatever).

The Nikon D2x uses a 4 channel output sensor and does white
balance correction at the analog level *before* the image is
digitized.

Of course the NEF file provides enough data to make corrections,
which may or may not be possible with a JPEG file.

Raw also because of the large amount of data that is available over the
bitmap formats of Tiff or JPG allows you to recover shadow and highlight
data that you couldn't do with TIFF or JPG without causing other problems
like lot of ugly noise in the shadows.

Nothing to do with a larger amount of data [or information]. See my comment
above.

A 16 bit TIFF formatted file is easily able to contain all of
the data available in a 12 bit NEF file.

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