any purpose for yellow/red filters?

Archived from groups: rec.photo.digital.slr-systems (More info?)

A newbie question..
I have some yellow and red filters from b&w film shooting,
and was wondering if there is any way to utilize with dig camera?
thanks
bill

Archived from groups: rec.photo.digital.slr-systems (More info?)

bill a wrote:
> A newbie question..
> I have some yellow and red filters from b&w film shooting,
> and was wondering if there is any way to utilize with dig camera?

Sure. Use them and get red or yellowed scenes.

It's actually a good question for the use of DSLR's in B&W mode. Anyone?

If an image is taken with a filter and saved in color, will the contrast
benefits of a red filter or yellow filter appear after conversion to B&W in PS?

Anyone try both combinations?

Cheers,
Alan

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Archived from groups: rec.photo.digital.slr-systems (More info?)

I wasn't aware that there was a b&w mode.
My D30 canon may not have that. I haven't found anything on
that in the user guide.
bill

"Ben Rosengart" <br+rpdss@panix.com> wrote in message
news:slrnd0klu9.rdl.br@panix5.panix.com...
> On Wed, 09 Feb 2005 18:32:57 GMT, bill a
> <custom4173@sbcglobalDOTnet.invalid> wrote:
>> A newbie question..
>> I have some yellow and red filters from b&w film shooting,
>> and was wondering if there is any way to utilize with dig camera?
>
> Are you doing B&W digital? If so, I believe you can use them the
> same as before.
>
> --
> Ben Rosengart (212) 741-4400
> x215
> Sometimes it only makes sense to focus our attention on those
> questions that are equal parts trivial and intriguing.
> --Josh Micah Marshall

Archived from groups: rec.photo.digital.slr-systems (More info?)

On Wed, 09 Feb 2005 19:23:46 GMT, bill a
<custom4173@sbcglobalDOTnet.invalid> wrote:
> I wasn't aware that there was a b&w mode.
> My D30 canon may not have that. I haven't found anything on
> that in the user guide.

The 20D does, but I don't recommend it for shooting JPEG. Better to
shoot RAW and do a more sophisticated conversion to B&W in Photoshop.
At least, this is my experience; I'm sure there's someone out there
who likes the in-camera B&W, and that's valid too. :-)

What's super-cool about the 20D is, you can shoot RAW in B&W mode,
and you get the same RAW file as ever, but the LCD-screen review
shows up in B&W.

Anyway, you could probably use your filters for this kind of
photography, as I said, though it's true that you can accomplish
the same effects more flexibly in Photoshop later, as someone
pointed out.

--
Ben Rosengart (212) 741-4400 x215
Sometimes it only makes sense to focus our attention on those
questions that are equal parts trivial and intriguing.
--Josh Micah Marshall

Archived from groups: rec.photo.digital.slr-systems (More info?)

On Wed, 9 Feb 2005 14:13:17 -0600, "me" <anonymous@_.com> wrote:

>"bill a" <custom4173@sbcglobalDOTnet.invalid> wrote in message
>news:tHsOd.7143$D34.5936@newssvr12.news.prodigy.com...
>> A newbie question..
>> I have some yellow and red filters from b&w film shooting,
>> and was wondering if there is any way to utilize with dig camera?
>> thanks
>> bill
>
>I will now talk about equipment I know very little about (re: DCD). Those
>filters darken their opposites before the light strikes B&W film. As such I
>suspect that a DCD records a full color image *before* it converts it to
>B&W, assuming it has the option to do so. I see no way this could work but I
>have been wrong before and this wouldn't be the first time. Ballsy answer
>huh!
>Film best,
>me
>
>[ducking back into my hole to count rolls of film]
>;-)

Well, even if you don't have a B&W mode on the camera, a simple
one-step 'desaturate' will convert the resulting filtered mess into
B&W.

The more I think about it, the less I would recommend using the
filters.

The CCD is pre-filtered. Each bayer pixel has a red, green or blue
filter on it already. This gives Photoshop the ability to lean on
different amounts of those channels to ultimately generate the B&W
shot from - and it's a lot easier to visualize when it's changing
right in front of you.

Whenever i've done it in the past, it's never been a single channel,
or dual channel with identical amounts change (which is effectively
what a standard green, red, or yellow filter would be). It's always a
fluid mix of the three channels (akin to a yellowy-green,
purpley-pink, or pale fuschia filter - which of course, don't exist in
my camera bag)

Putting a colored filter in front of a DSLR will doubtless make the
histogram function meaningless, possibly give you exposure issues,
definitely cuts down the light by a stop or more, risks increasing
flare, risks introducing vignetting, adds another layer of dirty
glass, and would definitely cause the white balance and subsequent
JPEG encoding to go nuts. I just don't see any reason to do it.

The reason I haven't tried using the traditional technique, is because
none of my B&W filters fit the weird 67mm lens Nikon put in the D70
kit. (Brainwave: Use my older lens... ah, so I *can* try this..)

Anyway, shoot this stuff RAW, no filters. Make your B&W in Photoshop.

Here's a demo:
http://luminous-landscape.com/tuto [...] tter.shtml

(The duo-tone stuff is worth a read too)

More on this, and some discussion:
http://www.photo.net/equipment/dig [...] bwconvert/

If you are a gimp fan:
http://www.gimpguru.org/Tutorials/Color2BW/


The most important stage:

Send the files to mpix.com who can use real silver-based B&W Kodak pro
paper for their digital prints (the heavy stuff you can cut people
with). They'll look amazing, I promise... unless, it's pictures of
plane tails.

B&W from inkjet can be problematic. Honestly, send them to mpix.

--
Owamanga!

Archived from groups: rec.photo.digital.slr-systems (More info?)

On Wed, 09 Feb 2005 18:32:57 GMT, "bill a"
<custom4173@sbcglobalDOTnet.invalid> wrote:

>A newbie question..
>I have some yellow and red filters from b&w film shooting,
>and was wondering if there is any way to utilize with dig camera?
>thanks
>bill

My guess is you might find some interesting effects, but considering
what a digital camera does in trying to identify what colors it
sees... who knows what ya get. For that matter, if your cam has
a calibratable white bal...then a few different colored papers will
sorta do the same thing but less extreme.(use them to set white).

Re a previous reference to the photosop bw conversion; in the
"channel Mixer" ; set it to monochrome and then with output
channel gray, adjust the slider red=+160, green=+140 blue=-200
and constant =0. You get pretty good contrast with that. Look
up doge & burn techniques if you want more intense. I especially
like Image Factory's "Convert to BW Pro" filter.

On my 20D, it has a bw setting with blue, red, green..etc effects
and if i didn't have, say photoshop, then i would be more impressed
with them.

rgds

Ken

Archived from groups: rec.photo.digital.slr-systems (More info?)

In article <tHsOd.7143$D34.5936@newssvr12.news.prodigy.com>, bill a
<custom4173@sbcglobalDOTnet.invalid> wrote:

> A newbie question..
> I have some yellow and red filters from b&w film shooting,
> and was wondering if there is any way to utilize with dig camera?

Shoot a whole roll of color with one of them on your film camera and
drive the lab nuts trying to correct.

Archived from groups: rec.photo.digital.slr-systems (More info?)

In message <FxtOd.7151$D34.5831@newssvr12.news.prodigy.com>,
"bill a" <custom4173@sbcglobalDOTnet.invalid> wrote:

>that's exactly the crux of my question, but since i am
>new to both the dslr and photoediting, i figured
>that my experimenting may not tell me much.
>hoping some knowledgeable person has tried it already :> )

Any filter will cause changes to a color image, even after white
balancing. Each of the three color channels has its own spectral
response, and the filters that you add effect the response of each
channel, but in a different way. Two reds that are apart in the
spectrum may record with the same sensitivity, but when you add the
filter, one may be more sensitive than the other.

If you filter so far that you darken certain channels completely (or
make them too noisy to use), then your b&w image will lose resolution;
usually dropping to only 71% if only the green channel is used, or 50%
if only red or blue.

If your subject is greyscale, you could actually use filters to shift
channels so far apart in sensitivity that you have more than 12-bits of
greyscale depth.
--

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