please let me know sir
Posted 03 February 2011 - 09:00 AM
please let me know...
Posted 14 February 2011 - 07:45 PM
Posted 14 February 2011 - 08:15 PM
Some claims made by lens manufacturers (especially fast primes or zooms) is that they are "best" or "optimized" wide open. I find it hard to believe; I don't think that this is even physically possible. I suppose some lenses, such as macro lenses, other specialized lenses may be designed with a very specific purpose in mind that this "rule" doesn't hold true.
What the two and a half stops is doing is balancing the improvements made to light scatter shooting wide open with diffraction of light skewing off of the aperture blades when the aperture really gets stopped down low, like F/16 on a 35mm camera lens. While, depth of field continues to increase all the way down, and this may be desirable, past a certain point, the offsets in image sharpness actually hurt the overall image, a net loss even with increased depth of field the whole image gets softer due to fuzzier optics.
At the same time, aesthetically, the increased depth of field might be objectionable to pulling off a pleasing composition. Some close ups call for diffusion.
So there are times where sharpness is NOT the be all and end all of movie photography. A lot of photographers, cinematographers spend a LOT of time trying to make older actresses' wrinkles disappear with sharp sharp modern Zeiss primes!
And the aesthetic nowadays is to shoot wide open. The "film look" is actually the "wide open lens film look." As a bit of a purist, I tend to start with the lens stopped down 2-1/2, especially when it is a zoom. So start at the technical best, but don't be afraid to embrace the "disadvantages" of softer glass. The most interesting movies, photographs, create their own looks that others will emulate, sometimes decades afterwards!