Letters to the Editor
Digital Photography
- Mark Lanterman's story "Capturing Models Digitally" [in the August issue] hit my spot. I've been looking for information about digital photography for some time. Every time I try to get information, the person I'm talking to assumes that I already know all about it. I don't know diddly! I've tried to read articles in photo magazines with no results. This article is the best anywhere! I'm on my way to buying a camera!
Jim Pate, Oakland, California
- Thank you for a very clear and useful article on digital cameras. I've not yet bought one, but am thinking along those lines, and your article gives me the info I need to make an informed decision. I'd like to see you do a similar article on photo software and color printers.
Frank Korman, Dallas, Texas
- The middle picture caption on page 69 stating that using a longer focal-length lens will minimize depth of field is a bit misleading. Using a longer lens changes the perspective. You can see how much shorter the Mustang in the middle picture looks than the one on the top. Although longer lenses often produce a shallower depth of field, depth of field is primarily a function of f-stop. By using a lower-number f-stop (larger aperture), the background will be blurred without changing the perspective.
John J. Seaton, Las Vegas, New Mexico
- Many digital cameras do not allow you to manually adjust the aperture (f-stop) of the lens. By backing away from the subject and zooming in, you can trick the camera into automatically opening the aperture, thus achieving the shallow depth-of-field effect.
Mark Lanterman, Fairfield, Ohio
Thanks to MA
- I just wanted to drop a line to everyone who helps to put articles in the magazine and say how much I love to read Model Aviation. To me, it is the best magazine that I have ever bought/received. I like the new section "From the Ground Up." Even though I have been flying for about two years now, there is always something for everyone to learn—even for veterans who have been flying for many decades.
I have learned things about RC airplanes and transmitters that I never knew. It shows me how an airplane control system is set up and which controllers fit different kinds of airplanes.
I especially love the section "Focal Point." It shows many different color schemes that I can use for airplanes I might build. I like to see what people can make without worrying about how much money they spent—just about the fun and memories of flying and building. The pictures are great!
I also enjoy "Worth a Closer Look," which shows new products with a photo and brief description.
Last, but certainly not least, thanks to the hardworking district reporters who go around the country to show pictures and reports of the hundreds of fly-ins and clubs they visit. I love to see what other RC people are doing at their clubs. Thanks very much to the Model Aviation staff who puts together this incredible magazine. Michael Carr, Charlotte, North Carolina
Best Covers
- The AMA magazine Model Aviation has undoubtedly the best covers of any magazine published. I appreciate the lack of article names, etc., on the cover.
Gene Midyette, Jefferson, North Carolina
- This note is simply to thank Mark Lanterman (and you) for the strikingly beautiful cover on the August issue. It is an "eye magnet" for me that in one photo captures the thrill of RC flight and the beauty of a fine subject. In more than 15 years of reading RC magazines, this one is my pick for the best ever. And Mark's article on capturing digital images is timely and well done. That guy knows his stuff. Thanks!
Chuck Kunce, Leesburg, Virginia
Electric-Power Quandary
- The author explains (in the July 2003 "From the Ground Up" installment "Introduction to Electric Power") the use of electric power versus glow-plug fuel/engines for model airplanes. His details are very well explained regarding components, performance, maintenance, and advantages compared to glow-fuel models.
However, I am at a loss to understand the use of equipment with mismatched or unlike voltages. He describes the motor as a Speed 400, 6-volt winding direct-drive system with APP connectors, and later identifies APP as Anderson Power Pole. Yet all the other power items—battery pack and charger—are stated as 12-volt operation. If I am missing something in this setup, will a 12-volt source harm a 6-volt motor and cause failure? Donald Kreis, Largo, Florida
- Response — MA / Bob Aberle:
You bring up an excellent point. At the start of this series I realized the options and variations can go on forever, so I chose components so a beginner wouldn't have to search for anything. My references to voltages were for identification purposes and were not meant to imply that everything operates at 12 volts.
The specified motor is a Speed 400, commonly available in different windings (typically labeled 4.8‑volt, 6.0‑volt, and 7.2‑volt). Each winding suits different setups; I recommended the 6‑volt winding for a beginner because it works well with direct drive (propeller mounted directly on the motor shaft).
Although the motor is labeled "6‑volt," in practice it is often run from battery packs of different cell counts. For example, an eight‑cell NiMH pack delivers about 9.6 volts (1.2 V nominal per cell × 8). In the article I used an eight‑cell 1100 mAh NiMH battery pack (about 9.6 V) with the Speed 400 (6‑volt winding) in a direct‑drive setup. That is an acceptable and common arrangement.
The "12‑volt" charger reference referred to the charger's input source capability—many chargers can operate from a 12‑volt car battery or from 115 VAC at home. The charger converts that input to the proper charging current and voltage for the battery pack; you should be concerned with the charge current, not the charger input voltage. For an 1100 mAh pack, a charge current of about 2.2 amps was recommended in the article. The particular charger I recommended (Watt-Age PF-12 Park Flyer AC/DC Peak Charger) can supply up to about 2.0 amps, which is close enough for our purposes.
In short: a 12‑volt source powering the charger will not directly feed 12 volts into the motor or battery—the charger regulates what goes into the battery. Follow the recommended motor, propeller, battery, charger, and speed controller choices, assemble the system, install it in the recommended Pogo ARF, and get to a local flying field. Seeing setups in use and asking experienced flyers at the field will quickly clear up these subtleties. Good luck as you proceed! MA / Bob Aberle
Transcribed from original scans by AI. Minor OCR errors may remain.
