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Photo Forum / Digital Photography / DSLR Cameras / July 2005

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The virtual of RAW

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l e o - 20 Jul 2005 04:43 GMT
People ask why use RAW format. I use it often for EC compensation and
color balance. Here is another reason. I always complains that many
photos I take in the day time with the sky way overblown and asked about
advice for a gradual filter.

http://www.fredmiranda.com/article_2/

I found out the article above and picked one of my photos as an
experiment. Using normal exposure curve, the photo looks good except the
clouds which are just a big white overblown mass. I used linear exposure
curve and underexposed 1.5 and recovered the details of the clouds.

I don't even need to take two pictures using a tripod. Hallelujah ...
l e o - 20 Jul 2005 04:45 GMT
> People ask why use RAW format. I use it often for EC compensation and
> color balance. Here is another reason. I always complains that many
[quoted text clipped - 9 lines]
>
> I don't even need to take two pictures using a tripod. Hallelujah ...

BTW, the camera is a 20D. I think doug should try to do some tests with
his favorite Panasonic FZ20.
John_B - 20 Jul 2005 18:17 GMT
leo,
You also could learn how to take the
photo correctly in the first place, then
you don't need raw.

But good for you, you can correct your
mistakes.

"l e o" <someone@somewhere.net> wrote in
message
news:1MjDe.990$0C.882@newsread3.news.pas
.earthlink.net...
> People ask why use RAW format. I use it often for EC compensation and
> color balance. Here is another reason. I always complains that many
[quoted text clipped - 9 lines]
>
> I don't even need to take two pictures using a tripod. Hallelujah ...
Owamanga - 20 Jul 2005 18:44 GMT
>leo,
>You also could learn how to take the photo correctly in the first place, then
>you don't need raw.

Rubbish. Are you seriously claiming that your color-balance is spot-on
for every shot you take. Think first: There are 50,000 different color
temperature settings, and 300 different tint adjustments - the
combination of which gives 15 million different possibilities of which
your dSLR may offer around 6 different ones to choose from for any
given situation.

>But good for you, you can correct your mistakes.

Twaddle. The vast majority of RAW adjustments are not done to fix
mistakes.

Signature

Owamanga!
http://www.pbase.com/owamanga

John_B - 20 Jul 2005 22:14 GMT
Owamanga you ever shoot with film?
Did you change your rolls every time for diffrent light
levels?

> >leo,
> >You also could learn how to take the photo correctly in the first place, then
[quoted text clipped - 15 lines]
> Owamanga!
> http://www.pbase.com/owamanga
l e o - 20 Jul 2005 23:39 GMT
> Owamanga you ever shoot with film?
> Did you change your rolls every time for diffrent light
> levels?

You didn't get it, so you should just use a film camera.
Owamanga - 21 Jul 2005 00:12 GMT
>Owamanga you ever shoot with film?

Of course, I started with film, then moved to slide, since I've had
the D70 (>6mo) I've taken 1 MF photo with a hasselblad  and the rest
is pure digital baby!

>Did you change your rolls every time for diffrent light
>levels?

You can't, it's impractical (unless you are doing commercial work,
maybe). Just like you still can't really do it with any significant
level of control on a dSLR today. People used to put up with yellow
tungsten photos, blue people standing in the shade and even took great
glee in cross-processing the negs to widen the gap between the result
and reality even further.

Not me, not now. I check and adjust color balance to taste on every
photo that's destined to become a print. The only way I could do this
before was to scan the negative/slide and work on the RAW file it gave
me.

But color temperature controls are just two of the 21 sliders on the
RAW importer dialog. Here are some other major ones:

Exposure. This usually needs a tweak. Often less than 1/3 stop which
is beyond my ability to control the camera at shoot time, but
sometimes more - especially if only one channel is close to clipping.

Anti-vignetting is nearly always employed to provide an evenly lit
image, esp. if you are shooting at a zoom's wider side. This helps
later with any off-center cropping you might do, preventing a dark
corner that you'd get if you didn't do this correction. Minor, subtle
yes but I know it's there.

Occasionally you want to increase the vignetting due to it's
compositional enhancement qualities. This slider does a much better
job than I've seen Photoshop do. Keeps it subtle.

Sharpening. I detest that happening in-camera as it does with a JPEG.
This should *always* be the final thing that happens to an image, not
the first. Sharpening has to be applied with output size in mind, and
no camera allows you to tell it that the destination print is 8x10 vs
6x4 vs a 600x400dpi email so it can modify the JPEG sharpening
accordingly.

De-noise filters. Applied automatically when you save as a JPEG, but
in reality the quantity of this effect you need changes with each
image and the ISO you shot it at.

Shadows. The JPEG gets a 'levels' cut at around 5%, anything below
rapidly being pushed to black. This helps cut down shadow noise and
gives the image some punch, but often this default is not suitable,
especially in high dynamic-range scenes.

Saturation. Again, each image is different. Portraits need less than a
landscape of Cinderella's Castle, Magic Kingdom. How can the camera
know what you are looking at? It doesn't.

On very rare occasions some of the other sliders get a twiddle:
Chromatic Aberration for example.

RAW isn't for everyone, just like doing your own film darkroom work
isn't for everyone, but to assume people do either just to fix
mistakes is way off the mark.

I believe that the vast majority who use RAW do so to maintain control
of the whole workflow, and not just let the camera make up some
bullshit defaults and be happy with that. The quality argument is a
secondary issue for me, I'm not anti-JPEG, just pro-RAW.

Signature

Owamanga!
http://www.pbase.com/owamanga

JPS@no.komm - 21 Jul 2005 00:58 GMT
>I'm not anti-JPEG, just pro-RAW.

JPEG is a dandy display medium; just not the optimal processing source.
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  John P Sheehy         <JPS@no.komm>

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Darrell - 21 Jul 2005 01:15 GMT
>>Owamanga you ever shoot with film?
>
[quoted text clipped - 11 lines]
> glee in cross-processing the negs to widen the gap between the result
> and reality even further.

In my professional shooting days with film we would use a colour temperture
meter, and filter to balance the chromes. With negative film we could
correct a fair bit in printing. At a wedding we could swap of a Blad back
with VPS to VPL and shoot the candle lit shots, sometimes we could cheat
with gelled heads, or later I would just do a soft fill with the modelling
light on our Lumedyne heads. I would only correct those about half way, as
warm is ok in what appeared to be candle light. I now shoot without a bag of
filters, in RAW but I treat the dSLR like a film camera loaded with chrome,
as the dynamic range of my dSLR is similar to slide film. The photo still
has to be correctly exposed! I prefer the 12 bit RAW over the 8 bit
TIFF/JPG, it gives my more control to my output. This is the same reason we
printed colour in-house, you will find a truly gifted custom printer in
commercial labs. But they often move on, and you have to train somebody
else. It's easier to have in studio colour lab, not cheaper! Now with
digital the work flow is different, there is post shooting production work,
that when people sent stuff to a lab was transparent. If you did your own
lab work it wasn't transparent. An average wedding coverage for a 50 shot
11x11" album was 8-12 hours shooting, and 80+ person hours in printing,
retouching and prep work to ship the prints down to NYC for binding. So
digital to me is a labour saving method, I can't undo a darkroom mistake,
like roller marks, cinched prints etc. I can back-up in Photoshop.
JPS@no.komm - 21 Jul 2005 01:26 GMT
>I now shoot without a bag of
>filters, in RAW but I treat the dSLR like a film camera loaded with chrome,
>as the dynamic range of my dSLR is similar to slide film.

You get a bit more full-color dynamic range if you use the sensor
array's native color balance; magenta filters over the lens (for
daylight), or over the flash.  Also, unlike slides, you can apply curves
to the processed image to bring out deeper shadows, albeit noisily.

Personally, I thing DSLRs at ISO 100 or 200 have a bit more dynamic
range than slide film.  And the limit that is there, at these lowest
ISOs, is the 12-bit digitization, not the sensors.  The sensors pick up
a lot more usable tones than can be expressed with the 4096 RAW numbers
at the lowest ISO.
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  John P Sheehy         <JPS@no.komm>

><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><
JPS@no.komm - 21 Jul 2005 00:29 GMT
>You also could learn how to take the
>photo correctly in the first place, then
>you don't need raw.

No matter how many uninformed people make this statement, it is still
incorrect.  RAW is like "better film".  Are you against better film?

Real photographers only use low-latitude slide film?
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  John P Sheehy         <JPS@no.komm>

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John_B - 21 Jul 2005 00:55 GMT
Well some photographers can get there equipment to work the
way they want, and not need editing like RAW to correct
there errors.  Some don't.

Raw is not like better film, infact print a correct photo in
raw (if you have the talent and software to do so) and print
the same correct photo in jpeg and you can't tell the
diffrence.

Raw vs. jpeg is more like negative film vs. slide film
With negative film there is more room to correct errors.
With slide film you get what you took.

I don't need Raw, do you?

> >You also could learn how to take the
> >photo correctly in the first place, then
[quoted text clipped - 9 lines]
>    John P Sheehy         <JPS@no.komm>
>  ><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><
JPS@no.komm - 21 Jul 2005 01:13 GMT
>Well some photographers can get there equipment to work the
>way they want, and not need editing like RAW to correct
>there errors.  Some don't.

RAW is the original digitization of the sensor voltages.  In-camera JPEG
makes an arbitrary re-mapping of these values, and then smashes them a
little flat with lossy compression.  Even without the lossy compression,
the JPEG set to normal parameters in daylight white balance throws away
almost 2 stops of red highlights, a stop and a half of blue, and about a
stop of green, on my 2 Canon DSLRs.  Not only that, but several RAW
levels in the highlight ranges that aren't clipped are posterized to a
single level in the JPEG, meaning that you have less capability to
enhance areas of low contrast to make them look the way your eyes and
brain see them.

>Raw is not like better film, infact print a correct photo in
>raw (if you have the talent and software to do so) and print
>the same correct photo in jpeg and you can't tell the
>diffrence.

That is circular reasoning.  Let me break your circle; you can't capture
the dynamic range in JPEG that you can in RAW.  If you limit the DR to
what the JPEG can do in your test, of course there won't be much
difference.

>Raw vs. jpeg is more like negative film vs. slide film
>With negative film there is more room to correct errors.
>With slide film you get what you took.

>I don't need Raw, do you?

If I want my images to have the kind of DR that I can see detail in with
my eyes and brain; RAW takes me a lot closer to that than JPEG does.
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  John P Sheehy         <JPS@no.komm>

><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><
Darrell - 21 Jul 2005 01:33 GMT
> Well some photographers can get there equipment to work the
> way they want, and not need editing like RAW to correct
> their errors.  Some don't.

RAW is not editing, RAW is the pure sensor data in full 12 bit (14 bit on
some equipment) with TIFF and JPEG the camera algorithms decides to throw
away 4 bits of info. There is more available dynamic range in RAW, it also
is not lossy like a jpeg file. Sometimes a lossy jpeg is good enough.

> Raw is not like better film, infact print a correct photo in
> raw (if you have the talent and software to do so) and print
> the same correct photo in jpeg and you can't tell the
> diffrence.

RAW is like better film, it's like shooting Kodak MAX versus a Pro film like
Porta.

> Raw vs. jpeg is more like negative film vs. slide film
> With negative film there is more room to correct errors.
> With slide film you get what you took.

Ok analogy, jpeg is like negative film because you settle for what the lab
tells you is a good print. RAW is like going into a colour lab and printing
my own prints hmmm I did that for 30 years ;) However jpeg uses a lossy
compression algorithm, and quality is lost ever time you open and resave the
image.

> I don't need Raw, do you?

But the discussion can be summed up as RAW is too hard, so I need outside
help. I agree 100% with you on correct exposure is key to good images, film
or digital. There are lazy shooters that will shoot RAW with the hope that
they can use the Photoshop "make it perfect" plug-in. I shoot RAW for all my
serious shooting, but might shoot jpeg for a quick web shot or happy snap.

Darrell Larose
Ottawa, Canada
JPS@no.komm - 21 Jul 2005 02:02 GMT
>RAW is not editing, RAW is the pure sensor data in full 12 bit (14 bit on
>some equipment) with TIFF and JPEG the camera algorithms decides to throw
>away 4 bits of info.

That's not the most accurate description of what is going on.  An 8-bit
TIFF's 0 - 255 might map from the 100 - 2200 of the 12-bit (0 - 4095)
RAW data in the green channel, 100 -- 1600 in the blue, and 100 - 1200
in the red channel, for a greyscale subject in daylight.  In the lower
parts of the ranges, the TIFF is actually more precise, and in the
higher part of the ranges, the RAW is more precise, because the TIFF's
values are the base of an exponent raised to the 2.2 power, typically,
representing the RAW values, which are linear.  Of course, the shadow
data comes from the less precise 12-bit linear shadows, so converting
them to 8-bit gamma-adjusted values does not realize their precision
potential.  however, demosaicing creates more values than are present in
the 3 separate channels combined, so the precision is sort of used,
anyway.
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Randall Ainsworth - 21 Jul 2005 05:33 GMT
> leo,
> You also could learn how to take the
> photo correctly in the first place, then
> you don't need raw.

Another twit suffering from DKS (Don't Know sh.t).
John_B - 21 Jul 2005 11:50 GMT
Randall Assworth,
Thank you for your useless opinion
but like usual you are wrong!

> > leo,
> > You also could learn how to take the
> > photo correctly in the first place, then
> > you don't need raw.
>
> Another twit suffering from DKS (Don't Know sh.t).
Randall Ainsworth - 21 Jul 2005 13:24 GMT
> Randall Assworth,
> Thank you for your useless opinion
> but like usual you are wrong!

Clever...never heard that one before.

The post I replied to said that people who used RAW didn't know how to
take pictures. That moronic statement shows that the person doesn't
know what they're talking about.

I shoot RAW about 99.999% of the time because it gives me more control
over the final image. I don't mess with white balance (and shouldn't
have to) and I've been very pleased with the prints I've had made.

I've been doing photography since 1966 and made a living at it for 16+
years. Anything else you'd like to know?
John_B - 21 Jul 2005 14:38 GMT
Well I am glad you didn't get hurt by my reply.
Actually I was just going to post an apology, why?
Because two wrongs don't make a right.

I also have been doing photography for over 20 years 14
proffesional

I have also been a Graphic Designer for Corporate layouts
and ads for just over 10 years.

I don't shoot raw (don't need to), and my photos are good
enough for me and my clients [just like slides].

But isn't that the real beauty of Digital?
Being able to choose the way you want to do it!
Thats what attracted me to DSLR, prior to that digital was a
joke :+)

> > Randall Assworth,
> > Thank you for your useless opinion
[quoted text clipped - 12 lines]
> I've been doing photography since 1966 and made a living at it for 16+
> years. Anything else you'd like to know?
Bill Lloyd - 26 Jul 2005 02:43 GMT
> leo,
> You also could learn how to take the
> photo correctly in the first place, then
> you don't need raw.

Ummm... NO.

For situations with high dynamic range, you can't "take" the photo
without help.

Sure, you can use an ND grad filter to take it "properly" in the first
place, but an ND grad is typically a straight line, and getting it
"perfect" where the horizon isn't completely straight is going to leave
evidence.  In the linked picture, the rock in the foreground would have
a dark top... so you coldn't GET this same exposure, period.

> But good for you, you can correct your
> mistakes.

Well it makes adjusting white balance and a number of other things in
post processing significantly easier, yes.
 
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