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Old January 23rd, 2006, 08:50 PM   #76
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1. Dennis, I have no clue what that is on the right side of the frame, but it isn't in the original footage. It seems to be an artifact of Sorenson. If anyone can shine some light on that...

2. I'm not sure what you mean by buzzing, but it looks ok on my monitor. Here's twelve seconds of uncompressed footage:
http://www.frozenphoenixproductions....ide_uncomp.avi

Won't be up for another 16 and a half minutes after this posting, so be patient.

3. The F-stop loss is small, but is still there. I'd estimate at least a stop.

Thanks for the comments. Keep em coming--I'll try to test what I can.
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Old January 23rd, 2006, 09:26 PM   #77
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If you are going to an a4 size for your EIA1956 chart, use photo paper to print it on. The grey scale seems to come up better on that.

I also selected the photo option hich prints colour, again seems to print the grey scale better and the fine detail a whole lot better.

You may get a colour cast in the first copy as the printer settles down. My printer is the Canon BJC7100 which has seen a few hot dry summers which doesn't help inkjets. There have been some improved technologies since.

The MiniDV codec apparently apparently hits a wall at 530 TV lines but don't take my word for it.

Five micron AO dressed moving groundglass seems to be good for 710 TV lines horizontal res as MiniDV produces sharp artifacts from the pattern to about 710 when it blurrs them together.

Don't take my word for this either as my methods are instinctual, copy others and are not all that scientific.
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Old January 23rd, 2006, 09:39 PM   #78
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Thanks for posting that Ben. It's hard to describe, but view the clip at twice normal magnification, then watch the bokeh areas. Picture a million little busy mosquitos. It may just be noise if the cam was dialing in gain, or something from the adapter itself. It's the fact that the noise is so "busy" that I'm wondering about.

Maybe some DV experts can ring on on this...

When you say 1 stop, is that with your F1.2 lens? Set at F/1.2?

Edit: Is that one of Dan's FF gears I see on your lens?
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Old January 23rd, 2006, 09:52 PM   #79
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I noticed the grain as well, not sure what it is - in the uncompressed footage it is really evident, not in the mov footage though.
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Old January 23rd, 2006, 10:08 PM   #80
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Ooohh...I thought you knew about that. That's the moving screen. What you're seeing is literally moving grain, the Intenscreen being vibrated.

I'm guessing a stop because that's about how much I have to move the aperture on my lens to compensate. On that topic--my GL2's lens is a 1.6, but in manual mode it'll only let me go to 1.8! And I know I've seen it at 1.6 before...anyone know why it's doing this?

And yes, that's one of Dan's gears on my 1.2. He offered it for free to five people under the age of 21 as a way of "supporting the young generation," and I accepted.
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Old January 23rd, 2006, 10:11 PM   #81
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Quote:
Originally Posted by Ben Winter
I'm guessing a stop because that's about how much I have to move the aperture on my lens to compensate. On that topic--my GL2's lens is a 1.6, but in manual mode it'll only let me go to 1.8! And I know I've seen it at 1.6 before...anyone know why it's doing this?
Ben, as you zoom in, the minimum f-stop you can use on the GL2 goes up. If you zoom out you will get back the 1.6. It's just how it normally changes as you change the focal length.
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Old January 23rd, 2006, 10:14 PM   #82
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Yes, it’s the grain of the Beattie. It’s also apparent in some of Dan’s candle pics, even when the screen is moving.

I actually like the look...
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Old January 23rd, 2006, 11:15 PM   #83
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I don't mind it, but I wouldn't mind getting rid of it either. All I would need to make it go away is a larger motor. Giving it more voltage will only increase the speed of the motion and decrease the radius of the oscillation. Less voltage does the opposite. It's a trade-off, and getting a larger radius without sacrificing speed just plain requires a bigger piece of hardware.
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Old January 23rd, 2006, 11:31 PM   #84
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I've found the grain induced by the Beattie screen is most apparent on really bright lights that are out of focus. I'm learning how to make sure not to have that a distraction in my shots.

I've found that footage shown on a TV doesn't show the grain at all. But with us looking at it "under the microscope" looking for *any* imperfection, on our high resolution monitors inches from our eyes, and yeah, you'll see it.

As soon as the HVX200 arrives, I'll be able to test whether it can be significantly seen on HD.

But, in short, Ben, and anyone else using a moving Beattie element, to answer that age old question, "Are we there yet?" Yes! We are! Close enough! :)
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Old January 24th, 2006, 07:34 AM   #85
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Quote:
Originally Posted by Steev Dinkins
I've found that footage shown on a TV doesn't show the grain at all.
I was about to mention that. On my CRT prod. monitor it's clear as day.

Quote:
Originally Posted by Steev Dinkins
"Are we there yet?" Yes! We are! Close enough! :)
Thank goodness. We've spent enough money and time to get there...whew.
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Old January 24th, 2006, 08:38 AM   #86
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I enquired with a technical man about noise in small video camcorders.

Apparently noise occurs at a constant level. In bright conditions it is not readily noticeable. Apparently at lower light levels when some gain is applied, it still stays buried in the detail of the image, but is there.

When we create large areas of softness in an image with a narrow depth of field, we are leaving a space for any noise to make itself visible where it might otherwise be hidden by textural detail which would be in the image.

The "grain" you are getting may not be entirely from the groundglass.

There is reference above to aperture on the GL1 being set as wide as it will go. Is this necessary because of a gain problem with the GL1. If it is not and the GL1 is over-riding and using a higher shutter speed to limit the brightness, then the groundglass texture is going to get frozen and visible in the image.

My understanding of the Letus is that the excursion of the groundglass is small. Give there may be a stop and start cycle or a slow and fast cycle if the movement tends to be more linear than orbital, then with a higher shutter speed, groundglass texture may become visible.

All this may be very irrelevent in your situation however there are the thoughts.

If you are adding power in order to speed up or increase the excursion of the groundglass, would there be any future in adding some weight ballast to the groundglass frame.
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Old January 24th, 2006, 09:47 AM   #87
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Steve/Ben when you say "not visible on a TV" what TV are we talking about? I've found most everything unpleasant ends up visible on the my 51" HDTV. Worse when projected from an LCD projector onto larger screens. From my point of view, the microscope comes out, we post up footage, analyze, correct, then move on.

I guess after seeing the footage, I'm wondering if I should be abandoning my spinner for 1/2 stop gain over a spinner. The beattie should be perfect if rotated faster, but then you have the whole noise/vibration issue. I'll confess that this "noise", where ever it's coming from, is very distracting to me...and I noticed it right away. I'll also confess that noise/grain in general drives me crazy. Steve is right though in that we are much more critical of these aspects than the average observer.

Hmmm. Food for discourse. And just another reminder that as Scottie says "Ya cannot defeat the laws of physics Captain".
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Old January 24th, 2006, 12:39 PM   #88
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Quote:
Originally Posted by Bob Hart
There is reference above to aperture on the GL1 being set as wide as it will go. Is this necessary because of a gain problem with the GL1. If it is not and the GL1 is over-riding and using a higher shutter speed to limit the brightness, then the groundglass texture is going to get frozen and visible in the image.
Well, it's a GL2--and all of the test footage has been shot completely in manual mode at 1/60 shutter, so there's no overriding going on. Grain becomes apparent pretty fast as soon as you start getting up into the higher shutter speeds.

Yes, there's inherent noise that comes with video, and party that's why most people are willing to accept noise that comes with shaking the Beattie. I guess I am.

And not to change subjects, but I just finished filming a scene of a movie I'm doing and I realized that it has very little to do with what you record with, but rather who you're recording. Acting draws people into the story, not depth of field. Good acting and shallow depth of field is quite a dynamite combination though. :)
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Old January 24th, 2006, 12:56 PM   #89
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Exactly! I was entirely excited when I saw my first adapter footage. Video obviously doesn't give nearly the same opportunity to draw the viewers interest to the "focal" point of your frame. I actually grabbed a few stills from the GS400 while the adapter was attached and got the old familiar SLR look, albeit at 4MB (well, really closer to 2.5MB). Very cool...a digital SLR, minus the 8MB quality.

When you get immersed in this subject, it's easy to forget until your wife walks over, looks at the footage, then makes the comment: "You did all of this to get that???" Lugging the 100lbs of blast media in five different grades into my shop (GG tuning), I wonder myself sometimes!

I severly doubt that any casual observer would pick out the grain Ben. My thanks for all the work you've shared.
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Old January 24th, 2006, 12:59 PM   #90
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Quote:
Originally Posted by Ben Winter
Acting draws people into the story, not depth of field. Good acting and shallow depth of field is quite a dynamite combination though. :)
Yes, this is more of what I like to hear around here, in addition to all the tech talk. In addition to "acting" I'd say "performance" is key, whether that's captured reality, abstraction of reality, or scripted work. But I think production talk only happens when we're finished with hardcore R&D mode.

Congratulations Ben. Be sure to post more footage of your work.
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