Als je even op het internet zoekt, vind je eenvoudig de sterke en de zwakke punten van deze lens:
Sterke punten
Surprisingly good optical performance considering the price. At the short end this lens delivers results indistinguishable from primes and top of the range L zooms. Absolute optical performance declines a little as the lens is zoomed out but I have made clear, sharp, well detailed photos of subjects 3 kilometers away, hand held at 300 mm. Quite impressive. Performance is really good wide open at all focal lengths, improving just a little at f 8 and f 11. A very versatile long zoom, an absolute must for the traveller with a Canon EOS camera.
...The new EF70-300/4-5.6IS does benefit a little by stopping down to f8. On an EOS 20D and at f8, image quality on real world targets almost approached that of the 300/4L
...Corner sharpness (on an EOS 20D with a 1.6x sensor) is also better with the EF70-300/4-5.6IS lens and chromatic aberration is a little lower.
Zwakke punten
Lens construction and design have some cost saving features, I guess you can't have everything. You either have the cost or the cost saving features.There is no distance scale, which is no big deal. With a long lens like this a distance scale is not much use anyway. The whole front barrel of the lens including the focus ring rotates with auto or manual focussing, be careful where you put the fingers of your left hand. There is no FTM, even though the AF drive is USM. The front lens barrel extends substantially when fully zoomed out.
Buyers note. Some examples of this lens have a strange optical fault, acknowleged by Canon. Images go soft in the corners at the longer focal lengths when the lens is held in the vertical ( portrait ) format orientation. My lens had this problem. Canon fixed it without demur, apparently by replacing one of the lens groups which contained the fault. After the fix the lens is working perfectly. This experience makes a good argument for buying lenses with full manufacturers warranty even though this cost a bit more.
Nog enkele conclusies:
SLRGear.com reviews the Canon EF 70-300mm f/4-5.6 IS USM and writes;
“it delivers excellent sharpness from corner to corner, across most of its focal length range. It softens slightly at 300mm and f/5.6, but stopping down to f/8 returns it to excellent sharpness. … Across the rest of its range though, it’s simply outstanding.”
Photozone.de reviews the Canon EF 70-300mm f/4-5.6 IS USM and writes;
“The performance of the Canon EF 70-300mm f/4-5.6 USM IS came as a total surprise. Unlike its predecessor the lens is capable to produce a very high performance throughout the zoom range without the significant drop in quality at 300mm typical for most consumer grade lenses in this range. It seems as if the new UD element helps to lift the optical quality significantly. Distortions, CAs as well as vignetting are also very respectable.”
Photo.net reviews the Canon EF 70-300mm f/4-5.6 IS USM and writes;
“The original lens was very sharp at 70mm (as is the new lens), but became softer when zoomed to 300mm and shot wide open. I typically tried to shoot at f8 if I was zoomed out to 300mm. The performance of the new lens is improved at 300mm. Both sharpness and contrast are increased and it’s possible to shoot wide open at 300mm and get good results.”
Conclusie: De Canon EF 70-300mm f/4-5.6 IS USM is een mooie lens. De kwaliteit verbetert iets als je het diafragma iets afstopt naar f/8. Als je pech hebt en een minder goed exemplaar hebt getroffen, dan lijkt Canon zonder veel problemen het defect voor je te willen verhelpen.
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(en wij maar met geld smijten om dure lenzen te kopen...we zijn harstikke gek eigenlijk). Maar wat is het toch een leuke hobby he?