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:
firstname.lastname@example.org or email@example.com
or by US Mail to: David Brooks, PO Box 2830, Lompoc, CA 93438.
Infrared In Digital
Q. I recently bought a Tiffen #87 infrared filter to use with my Nikon D100 digital camera. With it installed, I can't see anything through the viewfinder. If I take a picture and download it into my computer, I get a red and white image, which is definitely an infrared picture. The image is very fuzzy, and although I realize that this may be a feature of infrared images, it is much more out of focus than I desire. I don't know how to properly use this filter. Do I have to compose the shot before I install the filter, and then count on the automatic focus and metering system to produce an acceptable result, or is there something I'm missing?
A. Infrared light is at a distinctly different frequency than
the middle of the visible spectrum, and that difference in frequency affects
focus (distance). On most better, older lenses there was a red infrared focus
correction mark on the lens barrel. So (using manual focus) you could focus
on your subject visually, then note the focus position relative to the normal
marker, and move the focus ring to bring the focus to the red mark correcting
for the frequency difference. When you use an 87 filter it blocks out so much
visual light that most of the exposure is made by infrared and its frequency
difference causes a significant focusing error.
First you should switch your camera to manual focus mode. Then if you have a red infrared focus correction mark on your lens barrel, focus on the subject without the 87 filter, install the filter and correct the focus point to the red mark and make your exposure.
Keeping Scanned Photos In Order
Q. My problem is a strange one. I use a Minolta DiMAGE Scan Dual 3 film scanner on a Windows XP system and I have Photoshop 7 and Roxio Easy CD Creator Version 6. When I scan a roll of film and give each scanned file the same number that's on the film strip and try to copy in that order the files won't go where I put them. How do I get my files to go in the order I want them to on my computer and how do I get them to print in that same order?
A. Most computers today have a master folder on the hard drive called "My Pictures." Within that folder you may want to create subfolders for each roll of film, possibly naming the subfolder by the date the roll was taken (if you have more than one roll for a date put a -1, -2, -3 at the end of the date). Then direct all of the scans from a roll to the dated folder for that roll. Computers put files and folders in numerical order, automatically reading from the front of the file name. The trick is to append the file name. For instance, if you have a file that is 18A.jpg for the frame, then add 001-18A.jpg to the front of the file name to make it read as the first in a series. Add 002 to make it the second in the series. Once you have done that the computer will arrange them in descending order, and they will print consecutively in that order.
Digital Camera Profiles--Are They Necessary?
Q. I am relatively new to the concept of color profiles even though I have been completely digital for over five years. My dilemma is not great, yet I would appreciate a bit of guidance.
1. Do I need to use a color profile with my Olympus E-20N digital SLR? If so, I have not been able to find one online.
2. I have used Canon, Ilford, and Pictorico paper recently, and I have color profiles for the Canon and Ilford. The best color match with my monitor does not necessarily occur when I use the paper manufacturer-recommended profile. So, I have used a trial and error method: printing four images on one piece of paper, each using a different profile. Is this typical?
A. Although there are some advantages to working with cameras
that have selectable parameter profile settings, like the Adobe RGB profile
choice, the fact some cameras do not have this feature is more an inconvenience
than a serious deficiency that will affect final image quality. It may just
require a bit more color adjustment to obtain a desirable set of color image
characteristics after you download to your computer and image-editing application.
Printer profiles are, or should be, specific to the make/model of printer, the ink set, and the specific paper. Generic profiles for paper should be specific to a particular make/model printer if downloaded from a paper company's website. If you want better than generic profile performance you just about have to do your own custom profiling. The least expensive and most effective resource to do this is ColorVision's PrintFIX: www.colorvision.com.
A Raw Deal
Q. I noted your article on using raw files in the September 2004 issue of Shutterbug. But how do you use raw files on your computer if it refuses to open them? I have a Nikon D70, which will take raw NEF images, but I'm told I need Photoshop 7 with a plug-in or Photoshop CS to handle them. I'm running Photoshop 5 and can't afford the latest version. Is there any other program that will allow me to convert raw files to TIFF? For the moment I'm using JPEG Fine on the D70, which I was astonished to find yields files of only 72dpi resolution but sized 41x27". Is the quality of any blowups from these files going to be anything near to that of raw files?
A. I would most definitely suggest then that you purchase a copy of the new Adobe Photoshop Elements 3.0, which was recently released for sale and which has raw file support for nearly all current digital cameras including your D70. It is under $100 and provides an efficient, easy way to input and adjust camera raw files to achieve images that most fully utilize the capabilities of your camera.
Effective ISO "Film" Speeds With Digital Cameras
Q. I know film cameras very well since I have been using them since 1970, but digital cameras have me a little gun shy. I was going to buy a Minolta A2 because it has an external PC cord hook-up that I can use with my Speedotron Brown line system. I was set to order the camera until I read an article that said the A2 takes great photos in 50 or 100 speed and average in 200 speed, but the noise factor in 400 and 800 speed is totally unacceptable and thus makes this camera not such a good buy.
My problem is I shoot most of my film cameras in 400 speed and I like to enlarge to 8x10 and 11x14. Do you know if there is any truth to that magazine's claims, or are their tests too subjective? I do like this camera but if I have to I will look into others.
A. With all digital prosumer cameras as you increase the effective
ISO rating there is a tendency to generate more image noise. Whether the Minolta
is more so in this regard than another camera I have not had the experience
However, please be aware that with prosumer digital cameras you don't need to use as much film speed as with a film 35mm camera because the effective focal length is less, so you can shoot at larger lens apertures and obtain the same depth of field. In other words, to obtain the same angle of view as a film 35mm camera you need to use a shorter lens so you can use a larger aperture f/4.0 vs. f/5.6 and obtain the same depth of field, thus you can effectively use a lower ISO setting.