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Old April 3rd, 2008, 06:48 PM   #256
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jose what is the performance in nightime? how is it capable of handle lowlight? can you post something shot at night?
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Old April 3rd, 2008, 06:57 PM   #257
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So far, and due to limitations in the software (I hope), low light recording is not very good. You have to raise gain a lot and though noise is very low, it's noticeable when you set gain to 24-26db.

We'll see what happens with the new software. Hopefully they'll set a higher top level for exposure, so high gain levels won't be necessary.
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Old April 3rd, 2008, 07:37 PM   #258
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maybe that could help in that redish white overexposure: this was andromeda, andromeda was a dvx100 mod to get raw data from the sensor... it's not the same, but maybe some ideas can be applied to sumix... http://forum.reel-stream.com/viewtopic.php?t=778
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Old April 3rd, 2008, 08:07 PM   #259
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Jose, great work as usual! The color balance issues seem to be very common, even in much more expensive cameras... most consumer types have built in filters, correct? We could always add filters as needed, to a certain degree. Hopefully the new software will allow finer control to prevent those blown highlights. It would be great if gain could be controlled separately for each channel, but I do not think that is possible. I did also notice a bit of artifacting in the red flowers as they moved around, did anyone else notice that?

Daniel, since you don't need the IDE for the CD/DVD, you could use an IDE to CF card adapter for the OS. That leaves the SATA for your swappable drive. Less noise and power usage rather than running an additional drive for the system, and cheaper than a Solid State Drive (unless you meant a CF card when you said Solid State :)

It may just be me, but I would rather not use USB if at all possible.

IDE to CF card adapter...
http://www.addonics.com/products/fla...ad44midecf.asp
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Old April 3rd, 2008, 08:28 PM   #260
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Are compact flash cards fast enough to be used when recording direct to cineform raw 1080p? There're SATA to CF card adapters too.

http://www.addonics.com/products/fla...der/adsacf.asp
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Old April 3rd, 2008, 08:57 PM   #261
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Originally Posted by Jose A. Garcia View Post


The RAW 12bit option is not yet implemented, neither is 8bit lossless compression. So far you can just record using 8bit option.

Norpix... PLEASE!! Release the new StreamPix update!

Raw data is 3 times easier to store. However, only the new application software will provide this feature, although not as fast as what will be provided by StreamPix after CineForm coding. For now, you can only store raw frames in PC RAM.
I wonder how we missed adding this feature earlier.
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Old April 3rd, 2008, 09:07 PM   #262
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Originally Posted by Kyle Presley View Post
So what are these "new and interesting features" you speak of???? Frame-rate control? Curves?
The most interesting feature is that you will have access to the source code and see for yourself how things are done. Color correction is going to be automatic and by placing a color chart in front of the camera. we add details to the FAQ list as soon as we get some free time.
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Old April 3rd, 2008, 09:19 PM   #263
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Originally Posted by Daniel Lipats View Post
12 bit will work but you have to put the frequency to 36Mhz or less.

50Mhz and 12bit will turn to garbage. This may change with new software/updates.

50Mhz is a little less than 50 fps (two channesl A/D and 2 Megapixel frames) 12 bit uncompressed is too much GigE bandwidth at this frame rate. presently our in camera compression is only implemented for 8 bit data after LUT.
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Old April 3rd, 2008, 09:28 PM   #264
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Originally Posted by Daniel Lipats View Post
There may be some kind of hardware bottleneck prohibiting 12 bit at 50Mhz. Hopefully thats not the case and is only a limitation/bug of the software. Farhad could clarify this for us.

If it is a bottleneck it may be possible to get around it by just shooting a bit wider, say 1920x800. Or by limiting framerate to 24p.

I will test this a bit later.

Shooting 36Mhz increases sensitivity giving a brighter picture, but also raises the chance of rolling shutter distortions. ERS is not horrible at 36Mhz, but it is there on fast pans. Very usable though, not much of a problem. Its just important to be aware of it.
As I earlier said the bottleneck is GigE. We are implementing in firmware transfer of every other frame to PC, so camera can output at 75MHz and 12 bit (only skipping every other frame.) Also we are thinking about compression at 10 or 12 bit
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Old April 3rd, 2008, 09:46 PM   #265
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Originally Posted by Jose A. Garcia View Post
So far, and due to limitations in the software (I hope), low light recording is not very good. You have to raise gain a lot and though noise is very low, it's noticeable when you set gain to 24-26db.

We'll see what happens with the new software. Hopefully they'll set a higher top level for exposure, so high gain levels won't be necessary.

The key for low light situation is correct color correction. CMOS pixels R,G, and B, all are so sensitive to IR. removing IR with extra filter on front of lens must help. Then a non-linear color correction is needed for low exposure. we need a lot of Macbeth charts around to calibrate for every exposure, IR level, etc.
The sensor is sensitive to high blue, I think this must be exploited in low light situations, crank up the gain on the blue and use the out for general brightness.
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Old April 3rd, 2008, 09:58 PM   #266
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Originally Posted by Jose A. Garcia View Post
Are compact flash cards fast enough to be used when recording direct to cineform raw 1080p? There're SATA to CF card adapters too.

http://www.addonics.com/products/fla...der/adsacf.asp
I see we must consider adding flash memory adapter to the camera for raw storage while PC is just used for control and view finder with decimation. But this will be another camera.
I am not sure how CineForm codec compresses. For high quality work you need to keep raw 12 bit data. Sometimes in the future after gathering much raw video a software algorithm can learn from data and remove all Fixed pattern noise, add dynamic range by tracking pixels and estimating RGB intensities with another extra 2 bits accuracy. Technology long ago has been developed in the cold war era. You can wait a few years for cheaper computers and software and rejuvenate your old raw data movies.
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Old April 3rd, 2008, 10:44 PM   #267
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The fastest CF cards I could find are only 45 MB/s, would that be fast enough to record on-camera Farhad? The camera would need at least 75 MB/s for 24 fps, correct?

I think that CineForm is 15 - 20 MB/s, so that may work with the 300x or even the 233x cards (taking into account that those are peak speeds and may not be maintainable). The advantage to CF cards over HDD, even taking into account that you may be losing raw data, is that CF won't seize up when shooting in environments that may damage a HDD... and CF is silent. Hmmm, maybe a CF SATA-adapter RAID 0 setup could capture it raw :)

That 75MHz and 12 bit every-other-frame upgrade sounds great! That should help if there are any rolling shutter issues.
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Old April 3rd, 2008, 10:54 PM   #268
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I'm not sure if CF would be an ideal option. Not only are they not very fast but also very expensive. There is also storage limitations. The technology may improve over time but it may be easier to just use a faster interface. For example maybe fiber optic?

Higher exposure times will limit the framerate. It will also give us higher sensitivity.

Farhad, forgive me if I misunderstood but you said that 50Mhz is about ~50 fps which is just too much bandwidth for gige? If we limit the framerate by raising the exposure times or by just using some kind of limiter to 24p would 12bit work at 50Mhz?

I think that would be a fair compromise. 12bit limited to 24p (or whatever gige would allow) at 50Mhz.
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Old April 3rd, 2008, 11:07 PM   #269
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Originally Posted by Daniel Lipats View Post
Farhad, forgive me if I misunderstood but you said that 50Mhz is about ~50 fps which is just too much bandwidth for gige? If we limit the framerate by raising the exposure times or by just using some kind of limiter to 24p would 12bit work at 50Mhz?

I think that would be a fair compromise. 12bit limited to 24p (or whatever gige would allow) at 50Mhz.
Daniel, you are correct, Frequency limits the top frame rate. Lower frame rates can be set by software at high frequencies. Our firmware guys will perhaps give us the most economical option for minimizing the rolling shutter effect for 24p. The rolling shutter effects depends on the time cycle of reading one frame two pixels at a time (exposure only stops when the pixel is read.) Exposure is controlled by how long is the pause before starting to read the first pixel.
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Old April 4th, 2008, 03:51 AM   #270
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Originally Posted by Daniel Lipats View Post
I'm not sure if CF would be an ideal option. Not only are they not very fast but also very expensive. There is also storage limitations. The technology may improve over time but it may be easier to just use a faster interface. For example maybe fiber optic?
Daniel and Jose,

Have a think about SxS cards, they're expresscard based and fast. I think the specs are 800mbs but i could be wrong. The same cards as the EX1. Im sure i've seen motherboards that have expresscard interfaces (which is an extension of PCI so it's pretty direct to the system). Now that sandisk are producing them the prices will level out. They're robust and you can take them out and plug them into many laptops to pull the data off. In my plans i've been thinking about these as a solution. I've just shot 3 weeks or drama on an EX using them and they've been great.

I don't like the idea of hard drives swinging around in a camera, much prefer the idea of solidstate.

cheers
paul
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