To deal with grain I change to LAB color space, then use the median filter
on the a and b channels, and if needed the dust and scratch filter in the L
channel, masking the sky first if necessary.
Maris
----- Original Message -----
From: "Norman Unsworth" <unsworth_norman@aclink.org>
To: <filmscanners@halftone.co.uk>
Sent: Monday, July 16, 2001 8:31 AM
Subject: RE: filmscanners: Grain, Noise, et al
| Lynn,
|
| Yeah, I must not have that technique down. I can blur the blue channel OK
| but when I go back to the 'RGB' view, I don't see much, if any change. Is
| there a specific technique to use in PS 6 to do this? I've got some
pictures
| of the Grand Canyon, shot during overcast and stormy conditions - talk
about
| a lot of blue and, consequently, a lot of grain. The Canyon under these
| conditions had a blue cast throughout. Decent shots but lots of grain
after
| scanning.
|
| Norm Unsworth, Owner
| CS Golf (formerly Clark Systems Custom Golf)
| Outstanding Quality and Value in Custom Golf Equipment
| 609 641 5712
| Please send email to me at: csgolf@home.com
| Visit our Web Site at
|
| > -----Original Message-----
| > From: owner-filmscanners@halftone.co.uk
| > [mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Lynn Allen
| > Sent: Saturday, July 14, 2001 9:19 AM
| > To: filmscanners@halftone.co.uk
| > Subject: Re: filmscanners: Grain, Noise, et al
| >
| >
| > Norman wrote:
| >
| > >>From a practical, rather than a causative approach, how have
| > folks dealt
| > >>with this issue, both in terms of minimizing apparent grain
| > from scans and
| > >>in improving (ie: reducing) the appearance of 'grain' in Photoshop?
| >
| > Norman, your defocussing scheme is undoubtably the fastest way to reduce
| > grain, although you pay a penalty (but surprisingly slight) in
sharpness.
| > Some of us (notably Maris) have found that separating the photo
| > into its RGB
| > components, blurring the Blue "mask", and then recombining them
| > eliminates
| > much of the grain with almost no obvious loss of detail. On
| > occassion, I've
| > had to blur *all three* components by varying amounts--which of course
| > brings it back around toward the original concept of defocusing,
| > with much
| > more time spent but slightly better control.
| >
| > With Picture Publisher 8 I've been able to isolate grain and/or
| > noise pixels
| > and change their color closer to what it's supposed to be, but have
never
| > been able to pull that trick off with Photoshop. Maybe someone else has
| > figured out how that's done in PS. ?
| >
| > Best regards--LRA
| >
| >
| >
| > >From: "Norman Unsworth" <unsworth_norman@aclink.org>
| > >Reply-To: filmscanners@halftone.co.uk
| > >To: <filmscanners@halftone.co.uk>
| > >Subject: filmscanners: Grain, Noise, et al
| > >Date: Fri, 13 Jul 2001 10:26:39 -0400
| > >
| > >I wanted to seek the input of list participants into the question of
| > >minimizing grain and noise in 35mm scans. While it varies according to
| > >subject matter, predominant color, film type and speed, all scans seem
to
| > >have some degree of grain / noise not found in the prints. I've used
both
| > >Vuescan's ability to manually focus (actually, slightly out of focus)
and
| > >grain reduction to reduce what I'm calling grain but obviously there
are
| > >drawbacks in the form of reduction of sharpness, in either of these
| > >solutions.
| > >
| > >By way of background, I use a Minolta Scan Dual II, with Vuescan and I
| > >always scan at the maximum resolution (2820, I believe), usually 48
bit.
| > >Color and film settings I vary depending upon what will get me the
'best'
| > >scan.
| > >
| > >From a practical, rather than a causative approach, how have folks
dealt
| > >with this issue, both in terms of minimizing apparent grain from
| > scans and
| > >in improving (ie: reducing) the appearance of 'grain' in Photoshop?
| > >
| > >Norm Unsworth, Owner
| > >Clark Systems Custom Golf: Outstanding Quality and Value in Custom Golf
| > >Equipment
| > >609 641 5712
| > >Please send email to me at: clarksystems@earthlink.net
| > >Visit our Web Site at
| > >
| >
| > _________________________________________________________________
| > Get your FREE download of MSN Explorer at
| >
| >
| >
|
|
|
