Digital Help
Q&A For Digital Photography

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This department will attempt to provide solutions to problems readers may have getting into and using digital cameras, scanning, and using digital photographic images with a computer and different kinds of software. All questions sent to me will be answered with the most appropriate information I can access and provide. However, not all questions and answers will appear in this department. Readers can send questions to me addressed to Shutterbug magazine, through the Shutterbug website, directly via e-mail to: editorial@shutterbug.com or fotografx@mindspring.com or by US Mail to: PO Box 2830, Lompoc, CA 93438.

WYSIWYG--Or Is What You See What You Get?
Q. I have encountered a mystery in printing digital images that I am searching for an answer to. I combine images scanned from 35mm slides (using an HP slide scanner) together with images scanned off a flat-bed scanner. I compose parts of each together using Photoshop 7. I adjust hue, contrast, and saturation until they look perfect on the monitor. But when I print them on my HP ink jet printer they are too light or washed out. To get a decent print I have to darken the image considerably on the monitor, and even then it is a hit or miss thing if I end up with a decent print. The mystery is this wasn't a problem when I was using Version 5.6 of Photoshop. I really do not know if this is a software, printer, or monitor problem.
Duane Alexander

A. It is essentially all three. Your monitor, software, and printer all "speak" different languages and cannot understand what the other is saying, which in computer lingo means that each device is color independent (reproduces RGB in its own way). In short, your software hasn't the slightest idea of what you are seeing on screen and therefore sends irrelevant data to your printer, which it translates in its own way because it does not output RGB color consistent with any standard.
The industry solution is called "color management." Adobe Photoshop 7 supports color management but it must be activated and configured by each user to make it work. In addition, your monitor must be calibrated and profiled and that profile must be set as the default in the color management part of your operating system's Display/Monitor setup. Finally, some HP printers do not support color management, but are sRGB printers. But some do, and the driver installs profiles for the printer that allow making color managed prints from Photoshop that will match what you see on screen.
Sound complicated? It is a bit complex and demands a user put in a little effort to activate, set up, and configure color management on their system. I have written a number of articles on the various aspects of this subject providing how-to instructions over the last 2-3 years, some of which are in the Shutterbug archives on our website at: www.shutterbug.com. Unfortunately the information you need is too much to cover in the context of an e-mail beyond making you aware that your problem is recognized and there are ways to deal with it.

Evaluating The Evaluators
Q. I want to buy the Canon PowerShot G5 but I just read a review in Macworld that says it has a surprising amount of "purple fringe" for a camera that expensive. Is this serious enough for me to consider buying the Canon PowerShot
S50 instead?

A. I would take that "characteristic" of the report you referred to with a rather large grain of salt. My reasons would be numerous. First, I would question if a computer magazine actually employed a professional photographer camera tester to do the report. It would be rare if they did. Second, you can find some artifacts in almost any image produced by a sensor chip, if you enlarge the image big enough. The question is--does the artifact appear to the naked eye in a normal size print made from the G5's image file? Third, is this artifact fault confirmed by any other testers in their reports from sources like DPReview.com that are independent and deal only with digital cameras for a photographic audience? If you test just one sample of a mass-produced product, are you obtaining a typical performance in the middle of the manufacturing tolerances, or one that is a rare exception at the edge of the manufacturer's tolerances?
For instance, I think most members of the photo press have read Consumer Reports' coverage of cameras over the years. And, like me, they often find Consumer Reports' ratings do not reflect reality from a photographic perspective. Many of the earlier exceptions are the reasons why Consumer Reports often differs so radically from the evaluations of the photo press. Test engineers are not photographers, any more than computer experts are also usually not photographers.
I see quite a bit of chatter on the Internet about digital cameras, and a lot of users will find something to pick on with most brands and models. The only time to take this feedback seriously is if a significant number of them report the same fault--the rest is idiosyncratic likes and dislikes. I have not seen all that much pickiness in the web chatter about the Canon G-series cameras to indicate it has any consistent, serious performance faults.

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