Zoom vs prime

[Ron Sassoon]

Please can some of you Canon pro's help me with the following. I have the following two lenses and not sure which one will give me a sharper clearer portrait ???
Canon 100mm f2.8 macro lense and a Canon 24 - 70 mm f2.8 L zoom lense.
I am confused as would normally expect the prime lense to be sharper however not sure if the L series zoom lense at twice the price would have better optics ??

[wulf]

Have you tried comparing them both? Collecting opinions is great but there is no substitute for setting up some experimental shots and comparing them yourself. Try getting the subject at the same size in the frame to make up for different focal lengths (perhaps try 35mm, 50mm and 70mm on your zoom) and also try the same series of aperture stops on each trial.

You can then compare the details to get your own answers, as well as picking up other aspects of the lenses (eg. my 90mm lens does some fantastic things with blurred colours in backgrounds).

Wulf

[Ron Sassoon]

I am really excited by the background blur from the 100mm macro lense compared with the zoom. Will have to try and set them up with the same subject on a tripod. Will also take your advise on the different focal lengths and see if that makes a difference.

[rediguana]

Here is a comparison chart of the two lenses (zoom taken at 70mm, both at f/2.8. Remember this is a very small sample (1) so it may not speak to the quality of all copies of said lenses.

From that comparison, the 100mm is clearly sharper, as expected in a prime vs zoom comparison.

If bokeh is your thing, then the additional 30mm will give you more bokeh that the zoom can generate at 70mm.

[wulf]

That's a great site for comparisons (although it could do with a "real world" shot or two to demonstrate things like bokeh).

Wulf

[rediguana]

Originally Posted by wulf

That's a great site for comparisons (although it could do with a "real world" shot or two to demonstrate things like bokeh).

If you go to a specific lens review, then you can view a number of shots down the bottom of the review. I've spent a little time on that site

24-70f2.8 sample images
100f2.8 macro sample images