XIXAX Film Forum

Creative Corner => Filmmakers' Workshop => Topic started by: booji_boy on February 21, 2004, 08:19:21 AM

Title: Hi8 Depth of Field...
Post by: booji_boy on February 21, 2004, 08:19:21 AM
Is there such a thing? The built in lens on my sony trv-720 handicam has a pretty good manual focus setting, but is there anywhere I would be able to get an external lens that would provide better, and sharper manipulation of DOF? I've seen plenty of wide angle and telephoto lenses, but nothing else.

Thanks,

Rob.
Title: Re: Hi8 Depth of Field...
Post by: 82 on February 23, 2004, 11:13:48 AM
Quote from: booji_boy
Is there such a thing? The built in lens on my sony trv-720 handicam has a pretty good manual focus setting, but is there anywhere I would be able to get an external lens that would provide better, and sharper manipulation of DOF? I've seen plenty of wide angle and telephoto lenses, but nothing else.

Thanks,

Rob.


Can you adjust the fstop? Thats going to be your only option.
Title: Hi8 Depth of Field...
Post by: 82 on February 23, 2004, 11:17:12 AM
looks like its fixed at 1.6..   You just have to adjust the manual focus setting.
Title: Hi8 Depth of Field...
Post by: metroshane on February 23, 2004, 12:11:46 PM
Not only that, but the size of the ccd plays an important role.  It's just too small to give you the same control film will.  BTW, I'm not a film nazi...just stating facts.
Title: Hi8 Depth of Field...
Post by: Redlum on February 23, 2004, 01:10:25 PM
Yep. XL1's cant even do it that well. I'd try not to concern yourself with it, you'll only be disappointed.
Title: Hi8 Depth of Field...
Post by: booji_boy on February 23, 2004, 06:36:24 PM
How much of DOF is a result of the camera itself? I use a Pentax K1000 35mm SLR for stills, and the DOF is beautiful. If I put a lens like that on a video camera, wouldn't that improve it greatly? Are there any lenses for video cameras that provide a better DOF?
Title: Hi8 Depth of Field...
Post by: metroshane on February 23, 2004, 07:41:23 PM
Depth of field is controled by fstop.  the lower the fstop(the number, which is really a bigger aperature) the shallower the depth of field.  However, the chip on a video camera severly limits the usefulness of the lens.  So if you have the same 1.8 prime lens on a film camera and a video camera...you are still going to have less dof with the video.
Title: Hi8 Depth of Field...
Post by: Ghostboy on February 23, 2004, 07:51:54 PM
Plus, finding an adaptor for a hi8 camera might be kind of tough, if not impossible...I know I've never seen one. Best bet is to upgrade to something like an XL-1, which has adaptors that can handle different types of lenses. That way, at least you've got the glass (and the XL-1 chips are obviously going to handle a lot more information than a hi8's).
Title: Hi8 Depth of Field...
Post by: warmstepvision on May 30, 2004, 02:11:57 PM
Well not only the aperture that DOF depends on, it is also the magnification, focal length, and the circle of confusion. In film the dof is a lot more variable than in dv. Must be the differences with the focal planes and the way ccds capture light. Also technically there is a difference of depth of field and depth of focus, basically the dof is on the subjective side of the lens and depth of focus is near the image plane. But getting back to the original question there is a way to achieve that shallow dof everyone is fetching for. Mini 35mm adapters of course, www.dvinfo.net has a forum dedicated to just that. They use the relay system with the ground glass serving as a principle plane of focus. They have taken it far and people are coming up with some impressive systems. For all dv cinematography check out www.dvinfo.net.