Subject: Re: Physical size of lenses
On Nov 29, 2017, Paul Carmichael wrote
> Good morning everyone.
> I have a trivial question:
> On my desk in front of me are two lenses. Both Samyang primes. One is a 35mm
> f1.4 and the other is an 85mm f1.4.
> I'm just curious as to why the 35mm is so much physically longer than the
To start with both of those lenses are very capable, and of producing fine
photographs provided you are comfortable with manual focus. Both are fast
f/1.4, so one needs to look at the specs. An initial look shows the 35mm with
a larger filter size of 77mm vs 72mm for the 85. Next is the number of
elements in each the 85mm has 9 elements vs the 35mm with 12 elements. That
is where the answer to your question lies, the 35mm requires the additional
36.8mm of length to contain the 12 elements.
> And a related question: I have a Vivitar 35mm f2.8 that fits in the palm of
> my hand, whereas the Samyang is huge. I suspect the answer is obvious, but not to me.
Even if you take the f/2.8 vs f/1.4 into account, the Vivitar is a marginal
quality lens, whereas the Samyang, even though it could be considered a
budget lens, is of far superior quality in both construction and optics. That
said the obvious answer lies in the speed differences of the two lenses.
However, if the Vivitar has worked for you, and there are times a more
compact lens is required donâ€™t let my opinion stop you from using it
when you need to.