I have a Sigma 70-300 apo lens which does not get on very well with my Eos3, (BC blinking post below)

I now have the lens back from Sigma but Im thinking swopping it for a 100-400is. Although I find the Sigma lens very sharp has anyone else had these two lenses and can tell me if the Canon is any sharper.

Ive read tons of tests etc and have also read somewhere they are about the same in terms of sharpness.

I would also prefer to hear from anyone who has used slides to compare these two lenses.

Cheers,

Mick....

-- Mick Johnson (mickjohnson1@lineone.net), June 06, 2002

Answers

Both lenses are a little on the slow side, but the IS will give you a couple of extra stops to play with...that often means that you are able to use a slower finer grade film or maybe a polariser and get more saturation and thus a more pleasing result. I mainly take slides and appreciate the ability to add some saturation and colour at the input stage...with prints it can be done a little easier afterwards if necessary. There is a significant difference in price between the two lenses and I would expect some difference in performance based on this alone...otherwise why would anyone shell out the addition dollars? The reports I have read seem to clearly indicate that the 100-400mm comes up with some better performance stats...but you have to ask yourself whether the extra performance is worth the extra dollars and the additional weight. With prints you probably wouldn't notice it but with a blown up slide you probably would notice some difference in resolution and sharpness.

-- Lex (lex.bowden@vicpointss.qld.edu.au), June 06, 2002.

I used to own the Sigma 70-300 APO. I now have a canon 70-200 F4L and 300 F4L IS. My father has the 100-400L IS. We also have a Canon 100-300 USM.

In terms of a performance ranking, the 300F4LIS and 70-200F4L come top, followed surprisingly closely by the 100-400. Then there's a bit of a gap down to the sigma, which is slightly better optically (in my experience) than the Canon 100-300.

However, the clunky design of the sigma and slow AF make it a pain to use, and the Canon 100-300 is a far better lens overall. The 100- 400L IS is in a different league to the sigma lens, and if you think the sigma is sharp, you'll be redefining what sharp is. Add to that the benefits of IS, and the 100-400 is a much much much better lens. Which is why it costs several times as much.

-- Isaac Sibson (isibson@hotmail.com), June 07, 2002.

Thanks for the replies.

I really do want the 100-400 but just want to make sure its better (Sharper) than my Sigma and I do agree with Issac that the focus is slow and frustrating at times particulary in A1 servo mode.

I do like motorbike racing and think this lens will be just what I want.

Cheers,

Mick...

-- Mick Johnson (mickjohnson1@lineone.net), June 07, 2002.