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December 29th, 2007, 07:33 PM | #1 |
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Brevis Flip/ Sony EX1 test footage
Please forgive the not brilliant short. I had only an hour before it got dark but wanted to get SOME footage shot as I had promised.
See it here and read all about it too! http://web.mac.com/philip.bloom/Bloo...ooms_Blog.html |
December 29th, 2007, 07:50 PM | #2 |
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Took a look at the test footage. Thank you for taking the time !
Noticed about a minute in with sign/mirror pan up that there was a noticeable wobble to the image. I have experienced this with the HV20 too, and I am attributing it to rolling shutter issues, but may be all wrong about that. Noticed on a couple of shots, that center focus, with out of focus on edges, as you mention. I am wondering if that is a function of just not zooming in enought in the first place. Thanks again for taking the time. It is great to have someone who has used all of this equipment compare it. Looking forward to your HV20/Letus35 Mini detail...
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Chris J. Barcellos |
December 29th, 2007, 08:59 PM | #3 |
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Phil, the images look pretty good for a first shoot :-) The 20mm lens edge softness is quite apparent, and I wonder if infinity focus (micro-collimation) is set correctly? This may clean up the wide angle performance a bit. I've seen the same from my 24mm and there is likely no solution better than dialing in to f4.0 if you can. You'll find there is nowhere near the expected penalty in light loss doing this, so it's worth a try. Also check that the carbon chassis tube is seated properly (dead square) as this can cause edge wierdness. If you're not getting perfect edge to edge sharpness (take the lens off and focus on the imaging element only), something's not right. If the footage doesn't look like this, then pm me and we'll work a few things through.
You may also need to zoom in a touch more with the 20mm lens as the Brevis at full frame width is approx. 10% wider than the 36mm SLR image. In other words, you're filming areas of the 20mm lens' image cone that were likley never designed for imaging. You'll find you can get away with "super-normal" frame width at the 35mm and up focal range, but below 35mm, best to zoom in slightly to approximage a 36mm wide frame if you can. |
December 29th, 2007, 11:25 PM | #4 |
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I was zoomed in pretty far to try and lose it on the CF2Le. It was apparent but much harder to spot when I used the CF1LE. But I get this with the Letus Extreme too! I do struggle with perfect edge to edge with any adaptor on the EX1 and I was wondering if it is possible my lens on the actual camera isn't perfectly aligned? I wish more people would start using the EX1 and adaptors so they can compare. With the Extreme I really wasn't zooming in enough most of the time so lost most of the edge softness.
I did stop down as much as possible but it didn't make that much difference. Using the CF3L without flip on my JVCHD200 I got the worst soft edges with my 20mm, like a special effect (which I actually liked as an effect, used it on Anorexia 3 quite a lot!) but not on CF1L. How many other people have used really wide angles on the CF2LE? I think I need to stick it on my z1 for a good comparison. It's probably the best way. |
December 30th, 2007, 12:38 AM | #5 |
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I wonder myself Phil. Wide angle lenses are always a challenge, but if you can test with a reference 50mm or so (that you know is sharp) then at least the lens factor is eliminated. The first factor to eliminate (and I get caught time after time on this) is the video camera itself. From what you're describing, I'd be tempted to test the EX1 lens for spherical aberration at close focus distances.
Btw, did the solid carbon rods arrive? |
December 30th, 2007, 03:24 AM | #6 |
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yes they are terrific thanks!
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