Digital Photo Blog

August 18, 2008

George DeWolfe: sorta…

Filed under: Corrections — admin @ 9:42 am

Have “experienced” George DeWolfe’s “Digital Photography Fine Print Workshop” book.

Didn’t say read, because Mr. DeWolfe is a talented photographer but annoyingly and extremely full of himself.

It’s this latter part that made the book so hard to read. He spends a huge amount of time telling the reader how great he is, and how fortunate they are that he is sharing his wisdom.

Very tiresome.

And, of course, there are the parts where he’s wrong.

Such as in his basic workflow, where he places noise reduction as the last thing done to the photo, prior to sharpening and printing, because “Noise…is the exact opposite of sharpening.” Huh? “Blur” is the exact opposite of sharpening.

This is a computer, folks, not a sentient being. Computers run programs that are looking, in this case, for a very specific condition: CCD noise and color noise, so it can effectively remove them.

It is NOT looking for contrast enhanced, color corrected, noise. It will never find that… because that’s not what it’s looking for.

You want your noise removal done as _early_ in the workflow as possible, not as late as possible.

As to the book as a whole, I’d give these comments:

It’s a very basic beginner’s book. If you want Fine Art Print information, get “Fine Art Printing for Photographers” by Steinmueller and Gulbins.

DeWolfe’s artistic advice is much better than his technical advice. If you want a good book on photos in Photoshop, get Martin Evening’s “Adobe Photoshop CS3 for PHotographers.”

August 5, 2008

Epson 3800 prints too dark: FIXED!…

Filed under: Tales from the trenches — admin @ 10:07 pm

… at least for me. As soon as I went from PS CS2 to CS3, my prints came out 1.5 or 2 stops too dark. Drove me nutz.

Search on the web, and I see I’m hardly alone. Call Epson, and they admit it… but have been working on a fix for nearly a year now. Sigh.

Then tonight, I’m determined to find it, and I start mucking about. One of the things I did was turn on print preview, with my chosen paper profile. And on a whim, I clicked on “Preserve RGB numbers” and saw exactly what the printouts look like: way too dark. A clue!

Off to Adobe help, where I find that the definition of “Preserve RGB numbers” is ” Simulates how the colors will appear without being converted to the color space of the output device. ”

Hmmm… is it possible that the output is not be converted to the printer’s color space for some reason?

If so why, and what can be done about it to fix it?

Off to look at my profiles… to discover that I have two full sets of Epson 3800 profiles… one at /Library/ColorSync/Profiles and another at /Library/Printers/EPSON/InkjetPrinter/ICCProfiles/Pro38.profiles.

Hmmm… do I have a conflict here? Should not be, but on a whim, I delete the batch of profiles at /Library/ColorSync/Profiles, and head back over to PS to see how thing work now.

And the result is… “things work now!”

No more excessively dark prints.

Is this the reason that it was so hard to find? Double profiles? Some had them and some didn’t? (The ones at /Library/Printers/EPSON/InkjetPrinter/ICCProfiles/Pro38.profiles are, in fact, inside that package, so not very obvious.)

Did I find it, or were the gods just smiling on me? Taking pity?

See if that is your circumstance; see if that fixes it for you.

Good luck!

August 3, 2008

Setting White Balance with a Gray Card

Filed under: Techniques — admin @ 10:31 am

This is for the more serious photographers and videographers on the list, and there’s no doubt that some of you (certainly the pros) already know this… but some may not.

White Balance.

The human eye is very adaptive: take a sheet of typing paper outdoors, and it looks white. Take it indoors and it looks white. But that’s just our brains at work. Photograph it out doors and it looks slightly blue; shoot it indoors and it looks significantly orange. That’s because it’s not the paper – it’s the light.

In the film days, this was compensated for by using indoor or outdoor film, but in the digital age, it’s done in your camera. Every digital camera offers “automatic white balance” and often a range of cute little icons for outdoors (sunny) outdoors (cloudy) indoors (incandescent bulbs) indoors (florescents) and so on.

And better cameras will also have “custom white balance” as well.

Now: if you go to the trouble to set your white balance for a given lighting situation, there _will_ be a visible improvement in the color accuracy of your print.

The process involves choosing “custom white balance” in your camera’s menu, and then shooting something “white” filling the frame. That setting is then saved, and used as long as you don’t change the lighting in the current environment. (If you do change it; go outdoors; whatever, you have to go thru the process again.)

Except that my description above is incorrect. The bit about “shooting something white” is where it fails… because (unless you’ve paid for it specifically) “white” isn’t white. White typing paper, for example, has optical brighteners in it which reflect more blue, making it appear whiter to the human eye.

“White” as far as the digital camera (or digital video camera) is concerned is (here’s the key) -equal- amounts of 100% red, 100% green and 100% blue. On a scale of 0-255, for example, that would be R255, G255, B255. White light is an equal mixture of all the primary colors.

Your white typing paper is probably something more like R240, G248, B255. And those are not fixed numbers for typing paper… what I’m saying is that your white typing paper is really R?, G?, B?.

What you’re tying to achieve in white balancing your camera is, not surprisingly, “balance.” You want to photograph something under the “custom white balance” setting in your camera that is EQUAL amounts of R, G, and B.

And fortunately, that’s easy and inexpensive: take a trip to your local photo store, and buy an “18% gray card”… because gray IS, by definition, equal amounts of red, green and blue.

Take your white balance setting off of gray card, and you’ll see your color accuracy jump _way_ up.

“Balance” achieved.

Finally, as many of you know, if you also include the gray card in one of the photos in a given lighting situation, you can use that later on in Photoshop to help adjust the photo colors was well.

hth

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