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Old July 24th, 2004, 03:50 PM   #1006
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Okay, I removed more of the green. Use the same link.

So Ben, That's suppose to be bright back there?

The datasheet on the FillFactory site says that there should be a dynamic range of 64db, that's around 10 f-stops.
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Old July 24th, 2004, 04:03 PM   #1007
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"The datasheet on the FillFactory site says that there should be a dynamic range of 64db, that's around 10 f-stops."

We'll see. I'm definitely still getting the hang of it, and who knows if Sumix is taking full advantage of the sensor -- either with the camera or with the software.

I'm doing some tests to increase saturation, and they're promising. I'll post a couple movies in a bit.

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Old July 24th, 2004, 04:11 PM   #1008
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BTW,

If you shrink the image down to NTSC, it looks pretty good, like a frame from a film (although again I have no idea what the contrast ratio is in that scene, film has a lot of dynamic range). I've noticed there's a lot of aliasing, etc. in the full-res version, so I guess there needs to be some anti-aliasing added, or something. Like the circle on the shirt, the edge of your face (light side), etc. A lot of aliasing.

But of course you can't see that on NTSC :-)

http://home.mindspring.com/~jrod/hea...lders_NTSC.jpg

You know, maybe at $1000 for the camera we should consider these "super NTSC" cameras instead of HD cameras. I'm just saying I'm not sure we can get away with all that aliasing and bayer artifacting on an HD monitor.

edit: I got rid of the aliasing by using only the "Y" offset, so the image looks pretty good now. There is some JPEG artifacting though on the red of the shirt, that is NOT aliasing.
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Old July 24th, 2004, 04:24 PM   #1009
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No way am I going to this much trouble for NTSC.

I'm figuring out ways to deal with the saturation -- check this out.

There are major artifacts at 100%, but this lets you see the original color and the enhanced color.
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Old July 24th, 2004, 04:26 PM   #1010
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Really nice.
What about the Sky, what time was it??
Gain, gamma, contrast?

Could you post a full resolution .jpg frame?

There is also a problem with color balance.Look at the white signal near the tree....still a lot of green all over..
You need a higher gain on blue also...
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Old July 24th, 2004, 04:26 PM   #1011
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What are the artifacts? Can they be removed?

Also is there a way you can expose so that the sky doesn't clip, but still get the information on the street? Outdoor scenes with a hot sky (sun right behind the clouds, thin cloud-cover, etc.) are often 9-10 stops, so if you can get that, then you're fine.
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Old July 24th, 2004, 04:45 PM   #1012
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I'm working on how to remove the artifacts, or do a more suitable saturation operation.

It was very difficult to expose. I think I might go out and try another. It seemed impossible not to clip the sky, but I'll give it another shot.

The color balance is still a little off, but you get the point.

I posted a movie of the shot here. It's small, but it shows you that at 23-24fps, you can get a very stable, smooth image with no strobing, no rolling shutter artifacts, etc. The exposure time was around 25ms (a little more than 1/48th second). You can crank the exposure time up higher, until you're shooting with the shutter continuously open. Then you start to see rolling shutter take effect.

- ben
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Old July 24th, 2004, 04:53 PM   #1013
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Ben, could you give me a little more detailled info?
like gain setting for every color, gamma, contrast, etc.
Also at what time of the day this clip was captured.
Also if it was before 5 p.m most of the time you'll get a white sky, even on film, also it depends on if you have the sun in front of camera or behind...
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Old July 24th, 2004, 04:54 PM   #1014
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one of the problems is that all the 1 cmos or 1 ccd cams look like machine vision..not film...they don't have enough color! I hope the Altasense has good color..I know we can get it because my 10D is single cmos and it look GREAT

but maybe we need a chip that was designed for production not machine vision ;) I think the Altasense will do the trick

from what I have seen sofar I think the Micron looks better then that IBI5 you jut got...but then you need to shoot a shot with a blown out spot like a light bulb and see if it streaks the image or not?

is yours 2/3 inch?
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Old July 24th, 2004, 04:56 PM   #1015
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But if you go YUV and apply the correct compensation on color you get really good results...


Obin, could you someday post a couple of image sequences (16 bit per color channel or what the camera gives) in Tiff or TGA .
Just to see what are all those problems you talk about, cause I can't get a decent idea of them...
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Old July 24th, 2004, 04:58 PM   #1016
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We are having major recording issues with the CIneLink. It's not fast like it should be for record...will keep everyone posted on this as it gets resolved...
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Old July 24th, 2004, 04:59 PM   #1017
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Hey Ben,

That movie looks good!

Are the artifacts color fringing, especially on the trees?

Were the same artifacts on the "non" saturated version?

BTW, if that's a non-color-corrected image, then I think you can definitely underexpose the image to get the right exposure for the sky and do CC afterwards to bring up the dark cars, etc.
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Old July 24th, 2004, 05:03 PM   #1018
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Sure I will ...I guess I have sent images to Steve but not you guys...I will try and dig that email up and send it your way


<<<-- Originally posted by Juan M. M. Fiebelkorn : But if you go YUV and apply the correct compensation on color you get really good results...


Obin, could you someday post a couple of image sequences (16 bit per color channel or what the camera gives) in Tiff or TGA .
Just to see what are all those problems you talk about, cause I can't get a decent idea of them... -->>>
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Old July 24th, 2004, 05:05 PM   #1019
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BTW Obin,

Raw film doesn't look "good" either. If you're going to pack an image with a lot of dynamic range, you're not going to get saturation, and vice versa. Good saturation comes with increased contrast.

Take these images for instance:

http://www.24p.com/asc_web/35mm_girl.jpg

This is a 35mm frame with around 12-13 stops of dynamic range captured. You're not going to get "pretty" images when you do that. Her flesh tones are practically non-existant. Now increase the contrast, clip some of those whites, and you'll notice the saturation go up too. And then of course you can always punch the saturation also to get even better results.

But I think the RAW images we're getting right now are pretty good. Have you ever seen how "bad" the raw images from the Viper look? They are not pretty either.
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Old July 24th, 2004, 05:06 PM   #1020
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please, not to my email, the last time you sent me e-mail, my account got stuck.I got only five megs space.
Could you just send me link to download from?

Exactly, that's what happens with the positive material you see projected.
It has not much more than 256 shades of gray (around 5 stops) and looks great.
The case is worst with positive stock like Kodak Premiere or Fuji High Contrast.Less dynamic range..
If someone saw Moulin Rouge, its copies were made on Premiere.
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