Attn: Jan and Panasonic: informal poll on removable lense for HVX-200

[Graeme Nattress]

To what sort of “resolution” can we expect these measurements to be, to the metre, decimetre, centimetre or what?

Graeme

– http://www.nattress.com – Film Effects for FCP

[Barry Green]

Well, that I don’t know. Didn’t ask that question. Hopefully Jan can clarify for us.

—————–
Get the most from your DVX camera. The DVX Book and DVX DVD are now available at https://www.dvxuser.com/articles/dvxbook/ and at Amazon (https://tinyurl.com/54u4a)

[Brian Wells]

Your assessment is terribly inaccurate.

In Super35mm motion picture speak, a DVX100 with a 0.6X Century Optics adapter is roughly comparable to the field of view offered by a 12mm lens on a film camera.. as a generalisation… The DVX would actually be a tad bit wider.

[Toke]

Lack of wide angle is only for “non-changeable” lenses.
In 2/3″ there is 5mm primes from all manufacturers and zooms from 4.4mm and prices start from under 10k.
Eg. Fujinon has lots of cctv lenses that start from 2.8mm for 1/3″, 1/2″, 2/3″ & 1″ chips with cs- or c-mount.

[Jeremiah Black]

[Brian Wells] “Your assessment is terribly inaccurate.

In Super35mm motion picture speak, a DVX100 with a 0.6X Century Optics adapter is roughly comparable to the field of view offered by a 12mm lens on a film camera.. as a generalisation… The DVX would actually be a tad bit wider”

Brian,

I don’t mean to be rude, but, I’m not sure where you’re getting your numbers from.

On a normal lens (53 degree angle of view) focal length is equal to the diagonal of the image area. The diagonal of a 35mm piece of film is 43.27mm. The diagonal of a 1/3 inch CCD is .236 inches (5.9 mm)- yeilding a 22/3 ratio between the two, or 7.33. At 4.5mm (the DVX) at it’s widest point is a 33mm equivalent (4.5 x 7.33). Using the .6x century optics adapter, multiplying the magnification of the lens by the zoom focal length, gives you a 35mm film equivalent of 20mm. And that’s on the DVX which has, as you stated, the widest capabilities of the dv cameras out there. And since the PD-170 has a 6mm wide, the widest point it can achieve it is 26.5mm.

I’ve shot with the PD-170 using the .6x century optics adapter, and in my opinion is doesn’t look like a 27mm equivalent. To my eye it looks more like a 35mm or even 40mm equivalent. So, I’m hoping someone can chime in who knows his or her stuff, and lend a hand to the conversions.

– jeremiah black, NYC

[Barry Green]

[jeremiah black] “On a normal lens (53 degree angle of view) focal length is equal to the diagonal of the image area. The diagonal of a 35mm piece of film is 43.27mm. The diagonal of a 1/3 inch CCD is .236 inches (5.9 mm)- yeilding a 22/3 ratio between the two, or 7.33. At 4.5mm (the DVX) at it’s widest point is a 33mm equivalent (4.5 x 7.33). Using the .6x century optics adapter, multiplying the magnification of the lens by the zoom focal length, gives you a 35mm film equivalent of 20mm.

Your numbers would be appropriate for a 35mm still camera, but not a 35mm movie camera, which is what Brian was referencing.

The 7.33 multiplier you used is typically rounded off to 7.2 — you’ll find most manufacturers, when listing a “35mm equivalent” for a 1/3″ camera, will use 7.2x. So the DVX lens, at 4.5 to 45mm, is listed as equivalent to 32.5 to 325mm on a 35mm still camera.

With a cine camera, the frame is much smaller than it is on a 35mm still camera, so you use a smaller multiplier. For cine equivalency, the multiplier is 4.2. A DVX lens delivers the equivalent of 18.9 to 189mm on a 35mm movie camera.

With a .6 wide-angle adapter, the DVX matches the field of view of a 35mm movie camera with about an 11.5mm lens (or a 35mm still camera with a 20mm lens).

—————–
Get the most from your DVX camera. The DVX Book and DVX DVD are now available at https://www.dvxuser.com/articles/dvxbook/ and at Amazon (https://tinyurl.com/54u4a)

[Jeremiah Black]

[Barry Green] “The 7.33 multiplier you used is typically rounded off to 7.2 — you’ll find most manufacturers, when listing a “35mm equivalent” for a 1/3″ camera, will use 7.2x. So the DVX lens, at 4.5 to 45mm, is listed as equivalent to 32.5 to 325mm on a 35mm still camera.

With a cine camera, the frame is much smaller than it is on a 35mm still camera, so you use a smaller multiplier. For cine equivalency, the multiplier is 4.2. A DVX lens delivers the equivalent of 18.9 to 189mm on a 35mm movie camera.
“

Barry,

I can’t thank you enough for sheding some light on this for me. The math I’m using are entirely my own deductions, and, in a sense, it’s gratifying to know I was correct, if not entirely. But help me out here. Why is the diagonal of the frame smaller (around 25mm by your numbers) on cine cameras? 25mm seems awfully tiny. Also, shocking to think that 35mm cine only has a diagonal four times mini-dv.

And why does it still not look very wide when I rent the adapter and put it on? Still doesn’t look like a 12mm to me at all by a long shot.

thanks agian,

– jeremiah black, NYC

[Barry Green]

[jeremiah black] “Why is the diagonal of the frame smaller (around 25mm by your numbers) on cine cameras? 25mm seems awfully tiny. Also, shocking to think that 35mm cine only has a diagonal four times mini-dv.”

35mm film, as used in a still camera, runs through the camera horizontally. There’s 24mm between the sprocket holes. (the width of the holes, plus the thickness of the film on each side, bring the total dimensions up to 35mm). So on a still camera you get 8 perforations per frame, and the frame size is 36 x 24mm (w x h). The area between the sprocket holes is the height of the frame.

In a movie camera, you use the same (or basically the same) film, but run it through vertically. The area between the sprocket holes is now the width of the frame, not the height. As such, the frame is now a maximum of 24mm x 18mm.

A full-aperture Super35 frame has a maximum possible area of 24mm x 18mm, which is exactly half of the size of a 35mm still frame. Accordingly, lenses look more telephoto on a movie frame.

Now, that’s not where it ends — the actual, usable area of the 35mm cine frame is even smaller, due to two levels of cropping. First, one side is cropped down a couple of millimeters to make room for the optical soundtrack area. And, vertically, a lot gets lopped off to make for the 1.85:1 aspect ratio. So the actual, usable, visible area of a 35mm movie frame is more like 21mm x 11mm. That’s a total area of just 231 square mm, vs. a 35mm still camera’s total area of over 800 square mm.

Of course, it’s different if you’re shooting anamorphic (which uses a much larger 1.2:1 frame size, the full height of the frame and most of the width. And full-aperture Super35 lets you get the full 24mm size.

If you want to compare fields of view among various cameras and formats, the Panavision angle-of-view calculator is a most handy tool, at:
https://www.panavision.co.nz/main/kbase/reference/calcFOVform.asp

—————–
Get the most from your DVX camera. The DVX Book and DVX DVD are now available at https://www.dvxuser.com/articles/dvxbook/ and at Amazon (https://tinyurl.com/54u4a)

[Barry Green]

… soon, Ron promises we will be able to edit posts…

Okay, that was the wrong calculator I posted in the link. That was for the depth-of-field calculator.

This is the one that compares angle of view between different formats:
https://www.panavision.co.nz/main/kbase/reference/tblelenseqvform.asp

—————–
Get the most from your DVX camera. The DVX Book and DVX DVD are now available at https://www.dvxuser.com/articles/dvxbook/ and at Amazon (https://tinyurl.com/54u4a)

[Ron Lindeboom]

[Barry Green] “… soon, Ron promises we will be able to edit posts..”

But as I said, there will only be a 30-minute-or-until-someone-responds window of operation and we will never expand the functionality beyond that basis.

Not wanting hopes set too high,

Ron Lindeboom