Lens Terminlogy

[richardsperry]

Timed out,

 

Or say no memory card in a digital camera, nothing would be recorded. But angle of view and field of view continue to

exist.

[Peter_in_PA]

<p>"angle of coverage". I've never heard it discussed until this thread. "image circle" has been discussed (especially with regard to tilt-shift lenses), but not angle of "coverage". I've understood what is meant by angle of view for years, so I'm at a bit of a loss to understand this discussion and where it's going, and how it helps the OP.</p>

[mike_halliwell]

<p>The lens produces a image cone that obviously has an angle, this is often bigger than the chip or film gate etc. This is the lens's <strong>coverage.</strong> This angle is specific to the individual lens not just it's focal length. This angle doesn't change for CX, DX or FX sensor cameras. </p>

<p>I guess from the OP's point of view, the confirmation that if he likes the images produced by a lens of 30mm focal length as fitted on the camera and reported in View NX, then that's what you need to buy. If he changes camera format and wants to get the same FOV, you need to correct for the crop factor.</p>

<p>Maybe <strong>coverage</strong> shouldn't be used in these format discussions.... other than the <strong>reason</strong> DX lenses don't usually work on FX bodies.</p>

<p> </p>

[ShunCheung]

<p>Guys, the OP had a simple question. He had a bit of confusion that the focal length of a lens with different formats. That should have been clarified quickly.</p>

<p>Continuing introducing new terminologies that are not clearly defined merely adds far more confusion to the thread than necessary.</p>

[mike_halliwell]

<p>Sorry Boss...:-(</p>

[georges_pelpel]

<p>I understand the recommendations for a fixed focal fast lens but I would still recommend the AF-S 70-200/2.8 VR for such situation. It's only a stop slower than a 1.8 lens but offers much greater possibility. And it's very sharp shot wide opened at 2.8.</p>