Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens Review

The Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens is an ultra-compact and very well built telephoto zoom lens with excellent image stabilization and fast, quiet AF.

Model	Weight oz(g)		Dimensions w/o Hood "(mm)		Filter	Year
Canon EF 70-200mm f/4.0L IS USM Lens	26.8	(760)	3.0 x 6.8	(76 x 172)	67mm	2006
Canon EF 70-200mm f/2.8L IS USM Lens	51.9	(1470)	3.4 x 7.8	(86 x 197)	77mm	2001
Canon EF 70-300mm f/4-5.6 IS USM Lens	22.2	(630)	3.0 x 5.6	(76.5 x 142.8)	58mm	2005
Canon EF 70-300mm f/4.5-5.6 DO IS USM	25.4	(720)	3.2 x 3.9	(82 x 100)	58mm	2004
Canon EF 100-400mm f/4.5-5.6L IS USM Lens	48.0	(1360)	3.6 x 7.4	(92 x 189)	77mm	1998

I was immediately impressed by the solid build quality of the Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens. It is not a light lens for its size, but the 70-300 DO is solidly built. Canon has achieved their goal of compactness - see the comparison pictures below ...

You are looking at, from left to right, the following lenses:
Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens
Canon EF 70-300mm f/4-5.6 IS USM Lens
Canon EF 70-300mm f/4-5.6 IS L USM Lens
Canon EF 70-200mm f/4.0L IS USM Lens
Canon EF 100-400mm f/4.5-5.6L IS USM Lens
Canon EF 70-200mm f/2.8L IS II USM Lens
Canon EF 300mm f/4.0L IS USM Lens
Canon EF 400mm f/5.6L USM Lens

Pictured below are the same lenses in the same sequence in their fully-extended positions.

As indicated by Canon with the green stripe, Diffractive Optics (DO) elements were utitized in this lens to obtain the small size. This is Canon's second DO lens, the Canon EF 400mm f/4 DO IS USM Lens being their first. Canon's Camera Museum web site has a nice graphic illustration of DO technology.

Size and weight reduction are the big benefits to using Diffractive Optics, but there are some drawbacks to the current DO technology. The Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens circular aperture makes out of focus points of light round for a 6-blade aperture, but I don't care for the way the DO makes points of light into rifle target-like bokeh. Here is an example ...

The bullseyes do not show up often in real use, but a DO-caused bright, blurry halo shows itself more frequently. It shows up in out of focus areas - especially when the 70-300 DO's aperture is opened up. Some like it and call it dreamy - I personally don't like it. Here is an example ...

Utilizing Ring USM (Ultrasonic Motor), the Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens focuses fast in reasonable light - faster than the Canon EF 70-300mm non-DO IS USM Lens. Focusing is internal, FTM (Full Time Manual) focusing is enabled and the front element is non-rotating (useful when using certain filters or other attachments) - these are features missing on the similar-focal-length-range Canon EF 70-300mm non-DO IS USM Lens. The zoom ring is firm but somewhat spongy.

Being black and small, the 70-300 DO has a big advantage in the stealth area. You won't catch much attention when you are carrying this lens - an important safety factor for travelers to certain destinations. For some reason, subjects also tend to feel more comfortable when a little lens is pointed at them.

The Image Stabilization incorporated in the Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens is Canon's latest at this time (as always when new lenses are released) - and should be good for about 3 f-stops in handholdability. I found I could get decent handheld shots with a shutter speed as slow as 1/30th at 300mm. I love this feature. IS mode 2 is available for panning. The 70-300 DO can detect the presence of a tripod (when vibrations go below a certain level), but I generally turn IS off when shooting non-supertelephoto focal length lenses from a tripod.

Although this lens does not have an especially small diameter, it's filter size is only 58mm. Filters for this size tend to be significantly less expensive than the 77mm size found on many of the zooms in Canon's L Lens Series.

Model	Weight oz(g)		Dimensions w/o Hood "(mm)		Filter	Year
Canon EF 70-200mm f/4.0L IS USM Lens	26.8	(760)	3 x 6.8	(76 x 172)	67mm	2006
Canon EF 70-200mm f/2.8L IS USM Lens	51.9	(1470)	3.4 x 7.8	(86 x 197)	77mm	2001
Canon EF 70-300mm f/4-5.6 IS USM Lens	22.2	(630)	3 x 5.6	(76.5 x 142.8)	58mm	2005
Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens	25.4	(720)	3.2 x 3.9	(82 x 100)	58mm	2004
Canon EF 75-300mm f/4-5.6 III USM Lens	16.9	(480)	2.8 x 4.8	(71 x 122)	58mm	1999
Canon EF 100-400mm f/4.5-5.6L IS USM Lens	48	(1360)	3.6 x 7.4	(92 x 189)	77mm	1998

With a minimum focus distance of 4.6' (1.4m), the 70-300 DO delivers a maximum magnification of .19x (not great, but useable). Extension tubes nicely extend the 70-300 DO's maximum magnification to .26x and .46x for 12mm and 25mm tubes respectively. The 70-300 DO is not compatible with the Canon Extender 1.4x II or the Canon Extender 2x II.

Chromatic aberration (CA) is well controlled on the 70-300 DO. The 70-300 DO exhibits a tendency to flare and contrast is slightly lower than some of Canon's better lenses. On the other hand, vignetting is well controlled - primarily only noticeable near 300mm, f/5.6 on a full-frame body. Distortion ranges from some barrel distortion at 70mm to little distortion at 85mm to pincushion distortion by 100mm that gets and remains strong from 135mm through 300mm.

My biggest disappointment with the Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens is the lack of sharpness for the price of this lens. The 70-300 DO is soft wide open, but shows noticeable improvement by f/8. The 70-300 DO's sharpness leaves the much less expensive Canon EF 70-300mm non-DO IS USM Lens a serious consideraton for those needing this focal length range. The non-DO has an even wider aperture at some focal lengths (the DO aperture starts at f/4, goes to f/4.5 @ 90mm and to f/5.6 @ 185mm). Canon's 70-200mm L and 100-400mm L lenses are superior in sharpness to the 70-300 DO.

The 70-300 DO was not given a fast aperture to begin with, but stopping down to f/8 for a sharp image makes it slow. Image Stabilization helps greatly, but not if you want to stop action.

A zoom lock switch (above) on the70-300 DO is a nice feature - It prevents the lens from extending when you don't want it to. The trade-off is that it makes the lens slower to put into action. Use it when you want to, don't use it when you might need to grab a quick shot.

The Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens is shipped with a Canon ET-65B Lens Hood and a Canon LP1116 Soft Lens Case (when purchased from a reputable dealer of course). This lens is not weather sealed.

The price? Too high for the resulting optical performance to me personally. This is a lens I really want to like. I love the Canon EF 70-300mm f/4.5-5.6 DO IS USM lens's size, build, autofocus speed and top-notch IS, but, I'm not completely satisfied with the resulting image quality. As suggested in the review, one of the 70-200 L lenses such as the Canon EF 70-200mm f/4L IS Lens or the Canon EF 100-400mm f/4.5-5.6 IS L Lens will deliver better optical quality. As also mentioned, the Canon EF 70-300mm non-DO IS USM Lens is available for a much lower price - but it lacks the high grade features.

The 70-300mm focal length range is a useful one. People and nature are common subjects for this range. And because of its size, the Canon EF 70-300mm f/4.5-5.6 DO IS USM Lens is an excellent travel lens - having a lens that is easily carryable will get MUCH nicer shots than a lens left at home because of its size/weight. If this lens's features are what you need, then give it a try.