Stefan Official wrote: Knut. wrote: Stefan Official wrote:
I think the 28–70mm f/2 is simply brilliant. The quality is on par with prime lenses.
…
Anyway, for those who can make good use of that focal range, I hope you're already getting excited. If the new lens really has a constant f/2 aperture, it’ll probably be on par with primes again. I’m pretty confident about that.
RCicala wrote: Fred Miranda wrote: RCicala wrote: Fred Miranda wrote:
I'd say it's pretty unlikely a zoom lens is perfectly centered at all focal lengths.
I've only tested 5,000 zooms so far so all I can say is the frequency of a zoom perfect at all focal lengths is lower than 1 in 5,000.
Hi Roger,
What's the variance frequency for primes?
It depends greatly on which prime and how sensitive we look. Our standard is <10% variation at 30 lp/mm is perfect (I really careful pixel peeper with a high resolution camera might be able to see that, just barely, in some shots. But they would have to work hard to do it.)
At that standard there are a few primes where none are perfect. A really good prime would be over 90% perfect rate though, and most get to 95%.
There are good zooms where 95% are perfect at one focal length but never seen one perfect at all 3 we test (both extremes and the mid point). There's just too many things moving.
When Fred Miranda asked Roger Cicala about the variance frequency of PRIMES,
Roger Cicala who has tested > 5000 zooms on an optical bench states that none, not even one zoom was perfect at all focal lengths. It is a truth, that quite obviously many are reluctant to accept. Zooms have gotten, as I accept, very good and have convenience in their favour but unfortunately not excellence. It is allways a compromise on convenience.
Show me a photo that I couldn't take with the f/2 zoom and that would actually look better with a prime. I prefer to judge things based on real-world results rather than 1% lab differences. My 28–70mm f/2 zoom is optically better than my 35mm f/1.4 simply because the coating on the zoom is significantly more advanced.
Lens tip states exactly what I cited from Roger. Zooms may have one extraordinary focal length, in the the case of the 28-70 it is 50mm, and the other focal lengths are, well, OKish. Beaten by a prime at 28mm and at 70mm.
There is no doubt, if it reaches your level of good enough, there is no arguing, how could I? The point is, three fixed focal lenses will most likely exceed a zoom at two of the three focal lengths. Do you need it? Everyone has to decide for himself. Is it only 1%? No, more likely in the range of 10%. As Roger said „You can see it in your images, but you have to try hard“. For some it is worth it, for many not, and that is fine (technical perfection might be overrated in many cases).
But claiming that a zoom can reach the performance of fixed focal lengths at all the focal lengths covered is just simply wrong, even if it doesn‘t matter in practice to many.
Stefan Official wrote: Knut. wrote: Stefan Official wrote:
I think the 28–70mm f/2 is simply brilliant. The quality is on par with prime lenses.
…
Anyway, for those who can make good use of that focal range, I hope you're already getting excited. If the new lens really has a constant f/2 aperture, it’ll probably be on par with primes again. I’m pretty confident about that.
RCicala wrote: Fred Miranda wrote: RCicala wrote: Fred Miranda wrote:
I'd say it's pretty unlikely a zoom lens is perfectly centered at all focal lengths.
I've only tested 5,000 zooms so far so all I can say is the frequency of a zoom perfect at all focal lengths is lower than 1 in 5,000.
Hi Roger,
What's the variance frequency for primes?
It depends greatly on which prime and how sensitive we look. Our standard is <10% variation at 30 lp/mm is perfect (I really careful pixel peeper with a high resolution camera might be able to see that, just barely, in some shots. But they would have to work hard to do it.)
At that standard there are a few primes where none are perfect. A really good prime would be over 90% perfect rate though, and most get to 95%.
There are good zooms where 95% are perfect at one focal length but never seen one perfect at all 3 we test (both extremes and the mid point). There's just too many things moving.
When Fred Miranda asked Roger Cicala about the variance frequency of PRIMES,
Roger Cicala who has tested > 5000 zooms on an optical bench states that none, not even one zoom was perfect at all focal lengths. It is a truth, that quite obviously many are reluctant to accept. Zooms have gotten, as I accept, very good and have convenience in their favour but unfortunately not excellence. It is allways a compromise on convenience.
Show me a photo that I couldn't take with the f/2 zoom and that would actually look better with a prime. I prefer to judge things based on real-world results rather than 1% lab differences. My 28–70mm f/2 zoom is optically better than my 35mm f/1.4 simply because the coating on the zoom is significantly more advanced.
Lens tip states exactly what I cited from Roger. Zooms may have one extraordinary focal length, in the the casy of the 28-70 it is 50mm, and the other focal lengths are, well, OKish. Beaten by a prime at 28mm and at 70mm.
There is no doubt, if it reaches your level of good enough, there is no arguing, how could I? The point is, three fixed focal lenses will most likely exceed a zoom at two of the three focal lengths. Do you need it? Everyone has to decide for himself. Is it only 1%? No, more likely in the range of 10%. As Roger said „You can see it in your images, but you have to try hard“. For some it is worth it, for many not, and that is fine (technical perfection might be overrated in many cases).
But claiming that a zoom can reach the performance of fixed focal lengths at all the focal lengths covered is just simply wrong, even if it doesn‘t matter in practice to many.
Apr 12, 2025 at 03:59 AM
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