About Mike Carter Expertise I can answer technology related questions about file formats, camera features and options, and PC to camera interface issues. I will also provide suggestions and tips on general photographic composition and artistic layout.
Experience My experience in digital photography ranges across several brands and models, including Sony, Fuji, Cannon and Nikon. I presently do most of my work with a Nikon D70. I also have photo imaging experience with the digital darkroom - Adobe photoshop; where image color correction and rendering effects can be applied. Overall, I have 24 years experience in computer and consumer electronics technology.
Question I have a canon rebel digital camera. I have a 75-3oo mml zoom lens. Iwould like to increase my magnification. Would a doubler be a good choice?
Answer Hello Ray,
Doublers are an excellent means to bolster your arsenal of lenses. In effect, by the simple addition of a doubler, you actually double the number of lenses you can carry around.
Some typical caveats to watch out for when using doublers.
First, make sure you check with your manufacturer's suggested product list. With today's sophisticated electronics built into most lenses, you'll want to ensure you get a compatible device that will allow most if not all of the features built into your lens to make it back to the camera body. A lot of times, you will loose the auto focus ability anyway, especially at the higher magnifications, because the focal length is changed from what the camera is expecting with the doubler attached :-)
If the 1.4x or 2x "doubler" doesn't have the right number of CPU contacts, some things like range information or TTL metering may not make it back to the camera's internal computer if you aren't choosy about the doubler you purchase.
The only other real gotchya of any significance is when using a doubler, the light coming into your lens is passing through another lens element. No matter how good the lens is, the light will be degraded - so you need to compensate accordingly on your settings - what this generally means is that to get the best results when using a doubler, you should use the camera's manual exposure settings.
When I picked up my doubler, I started by bracketing my shots with all my lenses until I had a good feeling for the necessary adjustments. (Usually +1/2 to +2/3 EV at zooms 200mm +)
Having recently purchased a fabulous zoom lens myself, it was gratifying to see the doubler REALLY pull things in with the new lens. They're a great addition to any arsenal - just make sure you compensate!
