Mirrorless lens f stop
Mar 23, 2019 10:36:33 #
BebuLamar wrote:
Today the fast lenses are for NO DOF images not so much for low light. That is why you also see the popularity of the ND filter. In low light you still need reasonable DOF.
Mar 23, 2019 10:50:06 #
The new manual focus only Nikon 0.95 lens is a dinosaur out of the gate, made only to show that they can do it. The new Canon 1.2R lens is autofocus, and manual focus, super sharp, and not as large. It is a much more useable lens. Canon's mirrorless lenses, including a very compact 70-200, are much more numerous and faster. I tried the 28-70/2. It is a beast that has some of the best reviews ever, like a prime lens throughout its range.
Mar 23, 2019 10:55:24 #
AntonioReyna wrote:
The new manual focus only Nikon 0.95 lens is a dinosaur out of the gate, made only to show that they can do it. The new Canon 1.2R lens is autofocus, and manual focus, super sharp, and not as large. It is a much more useable lens. Canon's mirrorless lenses, including a very compact 70-200, are much more numerous and faster. I tried the 28-70/2. It is a beast that has some of the best reviews ever, like a prime lens throughout its range.
Canon does it right not first.
Mar 23, 2019 14:14:07 #
Mar 24, 2019 08:15:22 #
srherrmann wrote:
In a mirrorless camera, I would have thought that having a larger lens mounting diameter ( I believe it's 55mm for Nikons) would have provided for a faster lens design in terms of f stop. Yet the mirrorless lens for Nikon, (save the Noct 0.95) are still the same old 2.8, 1.8 run of the mill apertures. I know more light is gathered with the larger diameter, but without going to a larger aperture what's the point of going to 55 mm's if there aren't lens that take advantage of it?
Why? f/1.2 or f/1.4 (normal) lenses were sort of needed for film when ISO's only (for good film) only went to ASA 400. Even then even though I had (have) one f/1.4 lens I got by fine with most of my lenses being f/1.7, f/1.8, f/2.0, f/2.8, f/3.5, f/3.8, f/4. Seeing as I shoot almost exclusively with Prime Lenses between 19mm and 135mm I don't really need super fast anything. Digital cameras today are perfect with ISOs up to 1,200 or even higher.
I'm none to sure your idea here on lens optical theory is correct. I have many lenses with the same F-stop aperture, and focal length, yet different lens and front element diameters. Just different lens designs. An example I have: Old Pentax Auto-Takumar and later Super-Takumar both 35mm, both f/3.5, different physical sizes and diameters. Yet, both should take the same image. f/stops are a ratio of iris/pupal size to focal length. A f/1.4 is always a f/1.4. Though, does a view camera 210mm f/5.6 symmar seem anything like a vintage film 210mm f/4 Nikon, Pentax, or Canon Telephoto Lens? Very different application for different format sizes. And "tele" vs "normal" lens.
Mar 24, 2019 09:26:31 #
srherrmann wrote:
In a mirrorless camera, I would have thought that having a larger lens mounting diameter ( I believe it's 55mm for Nikons) would have provided for a faster lens design in terms of f stop. Yet the mirrorless lens for Nikon, (save the Noct 0.95) are still the same old 2.8, 1.8 run of the mill apertures. I know more light is gathered with the larger diameter, but without going to a larger aperture what's the point of going to 55 mm's if there aren't lens that take advantage of it?
I believe that out the gate Nikon was trying to emphasize a smaller/lighter package, at an 'affordable' price, that would entice current Nikon dslr users to give the Z bodies a try. Once they feel confident that the Z is not a flop the heavier, more expensive, lenses will be coming to the market place.
The new mount design was/is an investment in the future.
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Mar 24, 2019 12:57:41 #
jerryc41 wrote:
The f/stop is determined by a formula involving the measurements of the lens. Nikon decides what f/stop they want, and then they design the lens. The greater the f/stop, the larger, heavier, and more expensive the lens will be.
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