Thanks, Leon. No, I haven't added any filters, although I'm interested
and I'll take a look at those.
I've only used GIMP for a couple of years, and almost strictly for
professional work that involves very mechanical kinds of
hand-retouching. It's all straight photography. I haven't ever used
overal image manipulation, except for the basic corrections --
contrast, color, density, etc. Mostly I clean up backgrounds, correct
mistakes, silhouette, and related things.
But I know there are a lot more Photoshop things you can do with GIMP
if you go for the open-source add-ons. I'll have to look into it
You need to have some filters to play with. Try this/that and then
finally decide that none of them will do what you want/need. Then you
can get down to the real job of manually editing the image pixel by
pixel, spot by spot :)
Much of the time I find loading up GIMP is kinda like calling in the
National Guard when your only traffic light in town fails...
Most of what I do is adjust gamma, contrast, crop, unsharp mask, add
text and I've found a simple filter that will redistribute contrast (ie
boost low areas and reduce the highs). The latter is great for pulling
out detail lost in the shadows. For doing all that I usually run
Irfanview via Wine on Linux. You can do all that with GIMP but it would
take me an half hour as opposed to maybe three minutes with Irfanview.
GIMP's user interface is anything but intuitive...
Of course I also use XnView, XnConvert, Mtpaint, Fotoxx, Mashup, Image
Analyzer, FotoTouch (ancient Win3.xx)... different apps for different
But you speak the truth, many times it comes down to pixel editing/hand
retouching here and there. I haven't found any "magic bullets" for
getting that kind of work done, well, yet anyway. I keep looking ;-)
And _sometimes_ that sort of editing is the only way to properly blend a
defect. The filters don't always have the intelligence to handle
gradients that run three ways across a chip in the emulsion.
I'm always interested in finding the magic pixel-munger that will make
my job easier. <g> I've not found it yet, and I used Photoshop from
the first few months it was on the market; and PhotoStyler before
Meantime, a program that allows easy selection, paths, and the other
fundamentals -- with speed and accuracy -- is all I need. I have a
fast desktop with 6 GB of RAM, so Gimp works fast enough to satisfy
One thing I could use, though, is conversion back and forth to a
really broad colorspace that has a lightness (black and white)
channel. I used L,a,b with Photoshop. You get superior results with
unsharp masking by working only on the lightness channel (it avoids
color artifacts), and there are other things I like to do with it.
There may be a plug-in for doing it with Gimp, but I haven't looked.
I've gotten away with lesser colorspaces because I've done work mostly
for the Web lately, and it's not very demanding.
If you know of one, I could use it.
I'm not familiar with this (but learning). See if this blog entry
"...One of the hidden secrets of Gimp is that it supports the LAB color
space so you can get access to the L, a and b channels in an image.
This adjustment therefore produces similar results to those you can
achieve with my earlier post using Photoshop it?s just that the pro
in Gimp is a little different..."
Wow, it was right in there all along! Thanks, Leon. I can use that.
Playing with colors in L,a,b or other colorspace that has a density
channel and two-pole color channels (like HSB) is very tricky. I see
from the article that the author has tried to rationalize it. I'll
have to look it over.
A nice collection of useful tricks. Thanks. I've been working
self-taught, and did not know of those tricks. Bookmarked for the next
thing that she decides to share.
Right now, I am dealing with some 78 rolls of B&W negatives,
recently scanned. I've gotten quite a few ussable images out of
terribly exposed negatives. Not much I can do about when the shutter on
the Contaflex Super was sticking partially open -- lots of weird streaks
on those images. :-) About the time I move on to the Miranda F, and got
true lens interchangeability. (The Contaflex Super had only the front
element interchangeable, with a between the lens shutter.
While I (on Sun unix boxen) use xv for flipping through a lot
of images and selecting them, but gimp for serious working on them.
Since I don't use Windows, I can't use Irfanview -- but I supply
it on DVDs of images that I'm sending out to people who use Windows.
On 2013-04-22, Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:
[ ... ]
Or -- at least with some digital cameras (Nikon D-70 and D-300s
in my personal experience) you can set a menu item and then shoot an 18%
gray card in the same lighting, and use that as a color balance setting
in the camera so you don't have to do much in the post-processing.
And for really small subjects (bugs, small components, screws,
etc), you can drape a hankerchief over a wire frame (bent up from a
couple of coathangers), put two or three lights outside it, and get very
smooth and even lighting. Use the in-camera white balance to adjust for
light color -- with the 18% gray card if you need it. Usually the
automatic white balance will be pretty good -- unless your subject is
predomently a single color and a large percentage of the frame.
40 years ago when I did TV repair, most people had a definite green
tint to their TV sets. They would complain about a bad picture when you
replaced the CRT and did a complete setup to factory standards.
On Tue, 23 Apr 2013 23:02:45 -0400, "Michael A. Terrell"
Ayup. The eye tends to translate green easier than most other
colors..and a shit load of people tend to be green oblivious. Used to
drive me nuts in the lab. One of the reasons Im still..still a fan
That same fixture is available with RGB LEDs and a remote to select
I prefer the broad spectrum of the white phosphor, to three narrow
color bands. I'm not going to try to sway anyone's opinion. I just
like a spot that I can set something for a few quick shots without
spending an hour setting up the lighting. I bought some pieces of
fabric for backdrops. (60"*36") in black, gray & white. They have a
matte finish, so they don't reflect a lot of light towards the camera.
I've always used white bed sheets cobbled on to some type of frame, with
a half-dozen 100W bulbs placed around outside of the sheet enclosure.
You get a well-illuminated interior, without shadows or glare, and the
whole thing breaks down into a small package.
Might have to adapt different bulbs, now that the 100 watters are no
Sheets on a frame would work, washable, too. That's if you need big.
I've got something called "Studio In A Box" that I got cheap at a
closeout sale when Compuseless went out of business. This is a
collapsable lightbox about 2'x2'x2' and includes lights. Was about
$20. Works for reflective stuff like glassware, the purpose for
buying it. I know the company makes a slightly large version as well.
If all you need is a neutral background, sheets on a frame works for
that as well. Pro portrait photographers had rolls of patterned paper
they used on frames for backgrounds. If you need portable, 2x2s and
some casters should make up into something either able to be knocked
down or readily rolled around.
I have the several of the five caster bases from bad office chairs I
plan on using to hold backdrops & lights. The backdrops will be rolled
up on pieces of PVC pipe so you can change them in under a minute.
On Sunday, April 21, 2013 2:20:04 PM UTC-7, Gunner Asch wrote:
Why not just put a curtain rod on rollaround stands, and light with
halogen lamps? Put the camera on a tripod, and use the
self-timer to keep your hands from causing blur.
Flash lighting is for subjects that are moving, 'product photography'
doesn't usually benefit from freezing the action.
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