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Canon 70-300 f/4.5-5.6 DO IS review
Ongoing (started March 20, 2006)
This is a lens that seems to always generate a lot of controversy and a lot of differing opinions. Many feel that because of the DO (diffractive optics) the lens is overpriced, especially considering its slow aperture and the fact that performance wise it is about equivalent to the new 70-300 IS, and the fact that lenses such as the 70-200 f/4L have better optical performance for a fraction of the price. However, Kim chose to purchase this lens for one primary reason, its size. The DO is the most compact telephoto zoom ever made which makes it appealing for certain applications (like travel).
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The 70-300 DO IS on a 20D at 70mm |
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The 70-300 DO IS on a 20D at 300mm |
First Impressions
I was impressed by the size of this lens. It is extremely compact and fits in the LowePro Nova2 along with a RebelXT and another walkaround lens. I was also impressed by by the build quality. Despite not being an L, this lens has very good build quality. I also like the fact that Canon finally included a lock at the 70mm position to keep the barrel from creeping outward. I really wish Canon would just include this lock on ALL of their extending zoom lenses (much like Tamron and Sigma do). One of the things I noticed was how dim the viewfinder was. The slow aperture really becomes apparent if you are shooting indoors, which is where I did my evaluation (or maybe it had to do with the fact that I just finished testing the 200mm f/2.8L). The focus was quiet (due to USM), but was nowhere near as fast as what the 70/200 f/4 or the 200mm f/2.8 lenses can do.
The lens also has a switch to pick between Mode 1 and Mode 2 Image Stabilizer. You would use Mode 2 for shots where you are moving in just one direction (like a panning shot).
Tests
All tests were performed with (unless otherwise noted):
- Canon 20D mounted on a tripod with MLU and remote cable
- ISO 100, RAW, WB: 2850
Some cropping was performed, but no other photoshopping was done.
Sharpness
The first tests I performed were sharpness tests. All are 100% crops.
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| 180mm f/5 |
180mm f/8 |
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| 300mm f/5.6 |
300mm f/8 |
At 180mm, the lens is pretty sharp wide open and only slightly improves by f/8. At 300mm, it is somewhat soft wide open, but sharpens up considerably by f/8. In my opinion, these results aren't too bad.
Bokeh
One of the popular complaints about this lens is the odd bokeh. Many people claim the out of focus areas have a 'dreamy' appearance and out of focus highlights have a 'donut' shape to them. I tested the appearance of the out of focus highlights.
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| f/5 |
f/8 |
As you can see, there is a somewhat donut shape to out of the focus highlights, this can make for a different looking bokeh. I don't really like the way out of focus highlights are rendered, but to be honest in many of the pictures taken with this lens, I haven't found the out of focus areas to be too distracting.
IS
As with all Canon 3rd generation IS lenses, the IS on this lens is extremely effective. Just to see how far I could go, I tried to take a picture indoors at 200mm in low room light. Combined with IS and the great ISO 1600 performance of the 20D, this shot becomes possible.
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| 200mm f/5.6, 1/20sec, ISO1600 |
200mm f/5.6, 1/20sec, ISO1600 100% crop |
Conclusions
Though many people tend to be harsh towards this lens, I think it has a very important purpose. There is a philosophy which says that even the most mediocre of a lens in your bag can produce far better pictures than an amazing lens that stays at home. This is a fantastic travel lens, due to its compact size and weight. I think when travelling I would always pack this lens along with a walk-around, that fact alone makes it worthwhile. Also keep in mind that the optical performance of this lens isn't bad, and when it comes to color rendition and sharpness, it does a fairly good job. Lastly, if you are doing compressed landscapes with this lens (on a FF), then the 'donut' shaped highlights shouldn't be an issue. An ideal situation would be to complement this lens with fast primes (when utmost quality is important).
| Good |
Bad |
- Good Construction for a non L zoom
- Very compact, probably the most compact telephoto zoom ever
- Light
- Good sharpness
- Good color with neutral cast
- Effective IS
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- Expensive, especially considering all features of this lens save for the compactness can be had for $500 less
- Slow aperture speed
- Different look in out of focus areas, 'donut' shaped out of focus highlights. This may not be a problem for everyone, some may even like the 'dreamy' quality of the out of focus areas
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