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francois
10th May 2011, 10:17 AM
Supposing you have a 12-60, is there any value in getting a 11-22 considering the overlap? I can see the point in having a 9-18 to complement the 12-60 but not the 11-22.

Am I missing anything here?

StephenL
10th May 2011, 10:28 AM
I would say not. I own the 11-22, and have owned the 12-60 and the 9-18 (plus the 7-14). Of all these wide-angle zooms, I would rank the 7-14 as most useful, the 9-18 as a good all-rounder (though not weather resistant) and the 11-22 as least useful. I only keep it (the 11-22) so that I have a wide-angle option on my E-1 kit - the remaining lenses being the superb 14-54 Mk2, and the excellent 40-150 Mk1.

Tordan58
10th May 2011, 10:54 AM
I agree.
The 7-14 range would fit very well with the 12-60.
The 11-22 is almost overlapping the 12-60. Max angle difference is 89 vs 84, 5 degrees only.
The 9-18 has some overlap but the max angle (100 degrees vs 84) makes a difference. It is however not a high grade lens, it is not a fast lens but it performs well and most users seem satisfied with it.

francois
10th May 2011, 11:20 AM
Thanks, that confirms what I had in mind.

Mind you, the 7-14 is nearly 3 times the cost of the 9-18, so the latter will probably suffice for my modest talent.

StephenL
10th May 2011, 11:52 AM
3 times the cost, but in my view 10 times the lens! And that goes for the m4/3 versions as well.

the 7-14 is nearly 3 times the cost of the 9-18,

theMusicMan
10th May 2011, 12:10 PM
What you need to remember is the higher the increase in focal length of nearby lenses, the less increase in magnification, but the lower the length of the focal range of nearby lenses, the greater the field of view.

So... if you compare the Oly 70-300mm and the Sigma 135-400mm. The main difference at the high end is an additional 100mm from 300 to 400mm. For those looking for greater reach, this additional 100mm will yield only an additional x.33 (33%) magnification, and won't massively increase what you see through your viewfinder. As a general rule, what you see through the viewfinder at 300mm will be reduced by a third.

However, if you compare the 12-60mm and the 7-14 at the wide end of their ranges... you will see a significant difference through the viewfinder. 7mm is nearly half as much as 12mm, and so you will essentially see twice the field of view with the 7mm than with the 12mm i.e. approx 90% wider. This difference is significant in wide angle lenses more-so than it is in telephoto lenses.

Not very well explained, but hopefully enough to make you think.

Tordan58
10th May 2011, 01:11 PM
Hi,

I am inclined to disagree with the previous post. The relationship between focal length and angle of view is not a linear one.

For telephoto lenses we could approximate double focal length to half angular view, but this is not true for short focal lengths.

Attached is a chart showing focal length (4/3 system) on X-axis and angle of view on Y-axis. I simply plotted data obtained from specification from the available Olympus lens specifications. (Note that the odd values e.g. 420, 280 etc come from combining the EC14 and EC20 with various telephoto lenses, partly off topic.)





Focal length Angle of view
600 2,1
420 3
300 4,2
280 4,5
250 5
200 6,2
180 6,9
150 8,2
100 12
90 14
70 18
60 20
54 23
50 24
40 30
35 34
22 53
18 62
17 65
14 75
12 84
11 89
9 100
7 114

theMusicMan
10th May 2011, 01:31 PM
OK, I was not talking using accurate analytical figures as you are doing here, but... if I use your figures to illustrate what I mean...

300mm to 400mm provides a reduction in field of view of 1.2 degrees

12mm to 7 mm provides an increase in field of view of 30 degrees