Review of the Canon EF 70-300mm f/4.5-5.6 DO IS Lens
I was interested in finding a compact, relatively light telephoto zoom lens in the 75-300mm range to put in a light kit with wide-angle zoom that I could travel easily with and use for grab and shoot purposes with my Canon APS-C camera (20D / D60). Ideally, it would yield reasonable quality prints that I could enlarge well above an 8x10 inch print size if needed. I compared two compact Canon zoom telephoto lenses with other larger, heavier lenses. This review focuses on comparisons between Canon's relatively expensive EF 70-300mm f/4.5-5.6 DO IS lens based on diffractive optics against the inexpensive EF 75-300mm f/4-5.6 III USM.
Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens
Lenses Used in Tests
Which of these 300mm lenses would you want to carry all day on your shoulder, back or around your neck, and how much lens performance are you willing to sacrifice?
Click here for lens specification on size and weight.
|Review Summary for Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens|
Resolution and Modulation Transfer Function
Resolution of the EF 70-300mm f/4.5-5.6 DO IS lens was found to be comparable to other Canon zoom telephoto lenses tested in the range from 70mm through 200mm. Resolution of greater than 60 line pairs per mm was achieved at all focal lengths tested except at 300mm. Images produced by the lens were free of significant chromatic aberration at all focal lengths tested. At 300mm, the EF 70-300mm f/4.5-5.6 DO IS lens was only able to achieve resolution ranging from low 40's to high 50's line pairs per mm. Photographs of birds and other wildlife taken at 300mm and enlarged beyond 8x10 inch print levels noticeably lacked the sharpness and contrast that were achievable with a 300mm prime lens.
Method for Lens Resolution Measurement with Kodak Technical Pan
Digital Camera 50% MTF at 200mm and 300mm
What the EF 70-300mm f/4.5-5.6 DO lens lacks in resolution at 300mm, it appears to make up for with higher contrast and higher MTF scores. 50% MTF was calculated at 200mm and 300mm using this method.
Comparison of Image Sharpness at 300mm
Comparison of Image Sharpness Various Focal Lengths
Bokeh of the EF 70-300mm f/4.5-5.6
Lense Flare of the EF 70-300mm f/4.5-5.6
Out of focus background highlights with diffraction grid pattern and aperture diaphragm pattern.
The hexagonal pattern of the aperture diaphragm is notable in the background.
In this photo of a white-eared catbird in the San Diego Zoo, I stopped the lens down to f/10 to try to squeeze depth of field out of the image. This is shot hand-held in the shade at ISO 800, 1/100th sec at 185mm with a 20D. The image-stabilization saved the day.
Other comments on performance characteristics of the EF 70-300mm f/4.5-5.6 DO IS USM lens
Using Polarizing and UV filters with the EF 70-300mm f/4.5-5.6 DO IS
A lens tip page by Xavier Henri pointed out benefits and disadvantages of using filters with the lens:
The Canon EF 70-300mm f/4.5-5.6 DO IS USM is a compact, very fast-focusing zoom telephoto lens that provides generally excellent imaging function including excellent image stabilization at a high price. It is a weak performer at 300mm. It generally provides noticeably better performance than the cheaper consumer 75-300mm lens. Under some lighting conditions (e.g., backlighting of subject into the lens), the lens flares and renders images unusable. Because of its compactness and generally excellent performance with image stabilization, the lens is very useful for travel or other applications where you don't want to carry a heavy, long and easily noticed lens.
Gallery of images taken with the EF 70-300mm f/4.5-5.6 DO IS USM and Canon D60
2004, William L. Castleman
Posted 07 August 2004; last revised 06 June 2007