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  • #31
    Hi thanks for correcting me
    But, i hope my calculations are correct
    36/15.88=2.2x crop factor
    24/15.88=1.5x crop factor
    So a 24-70 will be 53mm-154mm lens
    Like that the changes will apply for all Full format lenses i mentioned above.
    But, why do ppl consider Tokino 11-16 lens for 2.3x crop ?? are my calculations abt this lens above correct ? if its correct the problem is solved we have 17mm wide for BMC Camera correct ???

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    • #32
      Originally posted by manigandan View Post
      Hi thanks for correcting me
      But, i hope my calculations are correct
      36/15.88=2.2x crop factor
      24/15.88=1.5x crop factor
      So a 24-70 will be 53mm-154mm lens
      Like that the changes will apply for all Full format lenses i mentioned above.
      But, why do ppl consider Tokino 11-16 lens for 2.3x crop ?? are my calculations abt this lens above correct ? if its correct the problem is solved we have 17mm wide for BMC Camera correct ???
      The sensor change is a new development that was just noticed the other day. People are still in the old mind set of 2.3.

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      • #33
        I read on another link that an 8mm fisheye will be a 10mm wide lens on a BMC Body
        can any one explain me how ?

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        • #34
          Originally posted by manigandan View Post
          full format =36mm width
          Bmc format =15.6mm width
          So 36/15.6= 2.3x is the crop factor when you using a full format lens on a Bmc camera.
          Correct (but only insofar as the aspect ratio remains the same). The real way to calculate the crop factor is to compare the diagonal of the frame, which takes a little more math, but when you're comparing the same aspect ratio (i.e., 16:9 to 16:9) then it's enough to just compare the frame width.

          similarly an aps-c camera width=24mm.so, 24mm/15.6mm=1.5x Crop.
          Correct.

          Aps-c Lens:
          1.Tokino 11-16 = 17mm-24mm on a Bmc Body
          2.Canon 17-55 = 25mm-82mm on a Bmc Body
          3.Sigma 30mm = 45mm on a Bmc Body
          This is right and wrong, depending on someone's perspective. Because it depends on what you're comparing against, not because of the lens itself! The millimeters of the lens don't change depending on whether it's made for APS-C or full-frame.

          Let me put it this way -- if I was to use your math, I might think that a Canon 16-35 EF lens, when zoomed to 17mm, would look much more telephoto than the Canon 17-55. But if you try it, you'll find out that instead they look EXACTLY the same.

          It doesn't matter what camera system the lens was made for, when determining what its field of view will be. The only thing that matters is what the actual focal length is. 17mm = 17mm, regardless of whether it was made for APS-C, or full-frame, or S35, or whatever.

          *the other thing to consider is a lens's circle of illumination, which is the difference between EF-S and EF lenses. An EF lens illuminates an entire "full frame" sensor, whereas an EF-S lens only illuminates the smaller APS-C frame. So if you put a lens on that has too small a circle of illumination, it'll produce an image that has a circle of image centered in a sea of black vignetting. But still, even then, a millimeter = a millimeter, and a 25mm lens made for a 1/3" camera will still show the exact same magnification as a 25mm lens made for "full frame".

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          • #35
            Let me put it another way -- who gives a flying fig what a lens "equates to" on any other camera body? You just need to know what a lens looks like on THIS camera body.

            And on a BMC, an 8mm is going to be a wide lens, an 11mm is going to be a mild wide, and a 20mm is going to be a "normal".

            Doesn't matter whether that lens comes from APS-C or "full frame", what matters is the mm.

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            • #36
              Originally posted by Barry Green View Post
              Let me put it another way -- who gives a flying fig what a lens "equates to" on any other camera body?
              Well come on Barry, I know the whole crop factor talk drives you up the wall. It does me a little as well but some people are coming from full frame, S35, or m4/3 cameras and they want to see what FoV the BMCC has compared to what THEY are used to with the lenses they already own and also want to know what lenses they still need to buy. I know when I went from the RED ONE to the AF100 I needed to adjust my way of thinking about lenses and had to wrap my head around the fact that my 50mm would now be used like my 85mm was on my RED ONE and so forth.

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              • #37
                Originally posted by Barry Green View Post
                Let me put it another way -- who gives a flying fig what a lens "equates to" on any other camera body? You just need to know what a lens looks like on THIS camera body.

                And on a BMC, an 8mm is going to be a wide lens, an 11mm is going to be a mild wide, and a 20mm is going to be a "normal".

                Doesn't matter whether that lens comes from APS-C or "full frame", what matters is the mm.
                how can a 20 mm made for full format body & a 20 mm made for aps-c body have same effect on a bmc camera when both have different crop factors to multiply with ????

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                • #38
                  Originally posted by manigandan View Post
                  how can a 20 mm made for full format body & a 20 mm made for aps-c body have same effect on a bmc camera when both have different crop factors to multiply with ????
                  A 20mm lens project a certain angle of view onto the sensor, when that sensor is large the angle of view is wider

                  The only difference between a 20APS lens and a 20mmFF35 lens is the image circle - the size of image it projects, not really relvant to the BMC seeing as any aps lens or FF lens image circle will cover the smaller sensor

                  There are various arguments about why a 20mm APS lens maybe better - flare, mass, and why a 20FF35 lens may be better, 'sweet spot is used'

                  but they are basically the same

                  S

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                  • #39
                    If we are talking about "WILL THE FOCAL LENGTH CHANGE" Then i would say "NO". i am talking about the magnification (ie) The Frame i see with 5D BODY MOUNTED WITH 16 MM LENS & BLACK MAGIC BODY MOUNTED WITH 16MM LENS Can never be the same.
                    How can i say this particular lens is same in bodth bodies. The Focal Length does not change But the lens solves a different purpose on a bmc body compared to 5d body. I think its a wide lens that am using but with bmc camera it is not a wide lens anymore it is a 35mm normal lens now. with respect to the area it is covering in my frame.

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                    • #40
                      A 5d is very wide with a 16 not so on the BMC

                      A20mm on a 5d is very/pretty wide, but a 20mm on a 7d is slightlywide, even if it a 20mm with an APS size image circle.

                      You were comparing apples with pears

                      As barry said..

                      BMD 11 = wide

                      24 or so = normal ish

                      50 = tele

                      Irrelevant of brand, image circle, maximum Fstop, minimum Fstop, Tstop, Cooke Prime, Tokina Zoom, bottle top, pancake, zoom, only the focal length affects angle of view.

                      S

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                      • #41
                        Originally posted by morgan_moore View Post

                        BMD 11 = wide

                        24 or so = normal ish

                        50 = tele

                        S
                        AGREED
                        So, Tokino 11-16 is enough to call a wide lens for Bmd. i am glad i found my choice of lenses for BMC with which i ll be happy to work with & i have all the lenses already
                        Expecting to shoot 2.5K Raw

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                        • #42
                          Its wide, but not ultra wide, about 25-6mm on a 5d equivalent

                          But with a similar sujbect size at a similar distance at the same Fstop it will have more DOF than a 26mm on a 5d

                          I dont think 2.8 is that attractive starting Fstop on such a small sensor if thin DOF is your thing

                          If I get the camera I will get the Tonka 11-16

                          S

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                          • #43
                            Originally posted by morgan_moore View Post
                            Its wide, but not ultra wide, about 25-6mm on a 5d equivalent
                            Sorry,Couldn understand this part.
                            Tokino 11-16 will be vignetting at edges on 11 mm. I personaly experienced this.
                            "25-6mm on a 5d equivalent" i cant understand this term "5d equivalent" ?

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                            • #44
                              If you have a 5d with a 25 mm lens your angle of view will be about the same as a BMC with an 11 lens - about

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                              • #45
                                Originally posted by manigandan View Post
                                how can a 20 mm made for full format body & a 20 mm made for aps-c body have same effect on a bmc camera when both have different crop factors to multiply with ????
                                Because lenses don't have crop factors. The sensors crop, the lenses don't. 20mm is 20mm is 20mm, period.

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