Q&A For Digital Photography
Digital Help is designed to aid you in getting the most from your digital photography, printing, scanning, and image creation. Each month, David Brooks provides solutions to problems you might encounter with matters such as color calibration and management, digital printer and scanner settings, and working with digital photographic images with many different kinds of cameras and software. All questions sent to him will be answered with the most appropriate information he can access and provide. However, not all questions and answers will appear in this department. Readers can send questions to David Brooks addressed to Shutterbug magazine, through the Shutterbug website (www.shutterbug.com), directly via e-mail to: email@example.com or firstname.lastname@example.org or by US Mail to: David Brooks, PO Box 2830, Lompoc, CA 93438.
To aid us in making Digital Help as helpful as possible, please be specific in your query and include components, including software, that you use. David says, “Make me guess the problem and I might guess wrong.”—Editor
Q. You have mentioned that you do not like coated photo papers and I am a bit confused. I have long suspected that matte paper does not have any coating, but that glossy paper does. I have an Epson 1400 and have been using Moab Luster with good results. However, my goal is a matte finish with a light gloss appearance. I have used some glossy papers with bad results. What are the main differences in the different papers?
A. The only kinds of paper that are used with inkjet printers that aren’t coated are plain papers, like typewriter/office paper. Both glossy and luster RC photo papers and matte fiber-based inkjet photo papers are all coated. What I do not “like” are RC “papers” which are really a very thin piece of cheap paper coated with plastic. The reasons for my dislike are twofold. First, the plastic is an unstable petroleum product with a very limited life, and is not acceptable for permanent documents by most governments and other institutions like libraries and museums. Second, the only inks that work well with RC papers are dye-based that are much more prone to light fading and color loss compared to pigment-based inks. All matte papers made for use with inkjet printers are coated papers to provide a finer and more accurate receptor for ink in its application. Your printer is a dye-ink printer and the Moab Luster is probably a good choice in terms of image reproduction quality with the Epson R1400.
The Appearance Of Depth
Q. I thoroughly enjoyed your review of Adobe’s Photoshop Elements 8 in the March 2010 issue of Shutterbug. I’m 70 and enjoy working with this program, although I’m a beginner. Would you be kind enough to tell me if there is a “layer mask” feature that I can use to blur a background?
A. I have seen third-party plug-in filters advertised that will do what you describe automatically, at least they claim to, but such an automatic process is not included in Elements 8, or at least I didn’t find it. However, there is a very easy-to-use selection tool so you can select the foreground subject, then invert the selection and apply a softening filter to the
background to make it look more distant and out of focus.
Shared Image Differences
Q. I do my photo editing on a 24” ViewSonic at 1920x1080 using CS4 and Windows XP. When I sharpen my 6-megapixel resolution images I use Smart Sharpen with settings in the 55 percent range of amount and a Radius of 1.2 pixels. The final JPEG images, which are maximally compressed, normally look very good. However, when I send the images to my wife’s Windows 7 computer with its 20” ViewSonic display set at 1400x1050, many of the images look super over-sharpened and rather noisy. The images are always displayed at full screen. It is possible that the images started out with more noise than I visually detected, and any sharpening can over-enhance that noise, but that does not really explain why the images look so different on the two different monitors.
A. First of all, have you reopened these images on your 24” ViewSonic after the initial save? How the images look in CS4 before being saved and after being saved, if in a compressed format, is usually not how they will look opened in another application or viewer, or on another machine. So if you have not done that on your 24”, try it. If you have and the images look fine, but are over-sharpened and noisy when opened on your wife’s machine, it may be hardware or even software differences in video, as well as differences between the LCD displays. ViewSonic doesn’t manufacture the displays but sells OEM displays manufactured by other companies with their labels on them, so even though the displays are of the same brand they may process video data quite differently.
But if the images began as digital camera JPEG files, adding any amount of editing and then saving again in JPEG will cause a loss of a lot of the image data content. And probably no sharpening is needed after a camera save in JPEG format. But if the images are not sharp enough, and if the camera has a control to adjust sharpening, do it there so it is included in the camera processing. Finally, the computer screen is a poor basis to evaluate image sharpness; making a print of the image is a better test.
ISO Paper Brightness
Q. I use Epson’s Luster and Enhanced Matte papers with ISO brightness numbers 97 and 104. Do these numbers relate to CD/m2?
A. Not directly, as print is reflected light and a display is transmitted light. In addition, you are referring to cheaper papers that are made with a fluorescent chemical added to the paper coating. This makes them appear to reflect more light than the base paper would, and these papers are referred to in the industry as OBAs. For printing for an art gallery or a museum, papers with high rag content and no OBAs are preferred, though more expensive. The reason is the extra brightness from fluorescent chemicals fades as an exhibited print is on display for any length of time. The chemicals lose their ability to react to ultraviolet light to look brighter than the underlying paper.
I never use those exaggerated brightness numbers to calculate a paper matching white for an LCD display that is calibrated and profiled for print matching. That would make prints made with those higher LCD brightness numbers look slightly too dark after the print produced is exhibited for a fairly short period of time.
The pro display industry standard for publishing is a display at 80.0 CD/m2 because the papers used in offset printing are less bright than the best papers used for inkjet exhibition printing, so I recommend 90.0 CD/m2 for inkjet print matching. Most users do not have the software and standard sample print illumination to do a measured print match like that offered in the EIZO EasyPIX software. The better inkjet papers without OBAs will measure brightness using a spectrocolorimeter at a percent of reflectance in the mid-90s, with natural white a few points lower than bright white.