Search found 1463 matches

by jsachs
June 12th, 2009, 6:34 am
Forum: Picture Window Support
Topic: Monitor Profile Desaturates Red & Green
Replies: 6
Views: 2750

Re: Monitor Profile Desaturates Red & Green

Did you mean to say you created a monitor profile or a set of montor curves?
by jsachs
June 11th, 2009, 5:54 am
Forum: Picture Window Support
Topic: Preview image too light in Convert or Extract Chan
Replies: 3
Views: 1935

Re: Preview image too light in Convert or Extract Chan

A difference of 0.8 is pretty much invisible to the naked eye. There are a number of reasons why the preview might not match the final image precisely such as not previewing at 1:1 or working with 16-bit B&W images - the readout tool on previews is also not as precise as on a normal image. As far as...
by jsachs
June 10th, 2009, 8:50 pm
Forum: Picture Window Support
Topic: Preview image too light in Convert or Extract Chan
Replies: 3
Views: 1935

Re: Preview image too light in Convert or Extract Chan

Unless you are previewing at a zoom factor of 1:1 you may not be getting an accurate impression of the preview image due to antialiasing artifacts. Also beware of apparent changes in brightness due to different viewing angles if one window is in a corner of the screen and the other is in the middle....
by jsachs
June 8th, 2009, 1:31 pm
Forum: Picture Window Support
Topic: Gamma converting monitor ICC profile to printer's profile
Replies: 9
Views: 3842

Re: Gamma converting monitor ICC profile to printer's profile

If you mail me a test print I should be able to measure it with my reflection densitometer - haven't used it in a while but if I dust it off it might just work. A camera light meter is not really a very accurate way to measure a target.

My address is:

Jonathan Sachs
7 Gregory Rd.
Lyme, NH 03768
by jsachs
June 7th, 2009, 12:15 pm
Forum: Picture Window Support
Topic: Gamma converting monitor ICC profile to printer's profile
Replies: 9
Views: 3842

Re: Gamma converting monitor ICC profile to printer's profile

If you purchase an inexpensive Kodak Q-13 step wedge and print the simulated version you can download from our web site, you should be able to compare them, but this will not take into effect differing DMAX and DMIN values.
by jsachs
June 7th, 2009, 11:47 am
Forum: Picture Window Support
Topic: Gamma converting monitor ICC profile to printer's profile
Replies: 9
Views: 3842

Re: Gamma converting monitor ICC profile to printer's profile

You can't determine this from the profile - it depends on the printer and the printer driver as well as the profile since they all work together as a system. The only way to determine the gamma is to print a test chart and read it with a densitometer.
by jsachs
June 7th, 2009, 9:51 am
Forum: Picture Window Support
Topic: Gamma converting monitor ICC profile to printer's profile
Replies: 9
Views: 3842

Re: Gamma converting monitor ICC profile to printer's profile

First the TRC flags in a monitor profile may either be a simple gamma value or a LUT (TRC stands for tone reproduction curve). sRGB actually uses a table because it treats the first few values different from a standard gamma curve although you would be hard-pressed to notice the difference. Printer ...
by jsachs
June 6th, 2009, 3:08 am
Forum: Picture Window Support
Topic: 3/2 Tones and Contrast and Brightness
Replies: 1
Views: 1300

Re: 3/2 Tones and Contrast and Brightness

No, the control points are customized to the tone ranges. Increasing the contrast of the highlights does necessarily decreased their average brightness however since white is fixed; similarly increasing contrast for shadows lightens them on average.
by jsachs
June 2nd, 2009, 9:53 pm
Forum: Picture Window Support
Topic: Additional Software in addition to PWP
Replies: 10
Views: 5228

Re: Additional Software in addition to PWP

I have not used Photomatix, but the new Stack Images command is designed to automate the process of combining bracket exposures to produce a high dynamic range image. There is a white paper that describes this process in detail.

http://ftp2.bmtmicro.com/dlc/Stack_Images.pdf
by jsachs
June 2nd, 2009, 6:21 pm
Forum: Picture Window Support
Topic: Vibrancy
Replies: 14
Views: 6631

Re: Vibrancy

There is no vibrancy feature in PWP. Vibrancy is not a technical term - what most people seem to mean is some combination of increased saturation and contrast.