Bob Hart
April 20th, 2007, 11:36 PM
For idle interest.
I had the JVC KY-F50 camera out to test a C-Mount film cam lens so offered a Letus35 Flip for XL up to the mount.
It seems that Quyen's current arrangement of a Minolta 50mm SLR lens and other optics he has in the path covers wide enough for a 4:3 2/3" CCD camera, so should work for 1/2" CCD as well.
Skewing the groundglass image around show a bit of brightness fall-off in the corners so you would need to use f1.8 lenses or f1.4 if you could get them and stay in the wider aperture settings.
How native 16:9 2/3" and 1/2" will fare I can't say.
The caveat to this test is that the JVC KY-F50 camera head uses 1/3" CCDs with an aerial image optical path which causes the CCDs to "see" a 2/3" image.
Whilst filming the Letus maintenance clip for Youtube posting, I took the trouble to paint flat black on the inside of the flip enclosure and more particularly, the frosted edge plus about a 1/10" margin around the outer perimeter of the unmounted achromat Quyen uses on front of his Minolta relay lens.
On my specimen at least, there was a noticeable improvement in apparent contrast and colour rendering.
Whilst I would not recommend the average person to dismantle the flip enclosure or disturb the relay lens attachment on back of the flip enclosure if it has not already been disturbed, flat blacking the achromat would be a worthwhile chore.
Make sure you have some thinners handy to clean off any paint spots which fly off the brush, straight away with a cotton tip. A few minutes wll be too late otherwise.
I had the JVC KY-F50 camera out to test a C-Mount film cam lens so offered a Letus35 Flip for XL up to the mount.
It seems that Quyen's current arrangement of a Minolta 50mm SLR lens and other optics he has in the path covers wide enough for a 4:3 2/3" CCD camera, so should work for 1/2" CCD as well.
Skewing the groundglass image around show a bit of brightness fall-off in the corners so you would need to use f1.8 lenses or f1.4 if you could get them and stay in the wider aperture settings.
How native 16:9 2/3" and 1/2" will fare I can't say.
The caveat to this test is that the JVC KY-F50 camera head uses 1/3" CCDs with an aerial image optical path which causes the CCDs to "see" a 2/3" image.
Whilst filming the Letus maintenance clip for Youtube posting, I took the trouble to paint flat black on the inside of the flip enclosure and more particularly, the frosted edge plus about a 1/10" margin around the outer perimeter of the unmounted achromat Quyen uses on front of his Minolta relay lens.
On my specimen at least, there was a noticeable improvement in apparent contrast and colour rendering.
Whilst I would not recommend the average person to dismantle the flip enclosure or disturb the relay lens attachment on back of the flip enclosure if it has not already been disturbed, flat blacking the achromat would be a worthwhile chore.
Make sure you have some thinners handy to clean off any paint spots which fly off the brush, straight away with a cotton tip. A few minutes wll be too late otherwise.