Forum: Pentax SLR Lens Discussion
12-07-2017, 10:36 PM
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yes, i totally asked that.
anyways, just wondering if some of you can shed some light to on this for me.
i've seen some lenses that are TINY, and others that are massive. yet their size doesn't related to their focal length. IE: the Tamron 90mm macro lens is pretty big lens when you compare it to the Pentax 100mm WR macro lens. all the while the 85mm by any company is usually much bigger than both of them.
yes, i get that the f-stops do vary significantly. and i get that wider open lenses tend to be bigger lenses, but it still doesn't corealte to the focal length.
case in point: pentax DA 50mm F1.8 vs pentax-FA 50mm F1.4
the 1.8 has a front element of 52mm vs 49mm of the 1.4.
and i get that often times, the bigger the front element, the more expensive the lenses are..usually. but aside from being more expensive, heavier, and bigger, what does a front element size do?
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