New DIY HD Cinema Camera Project

[Jamie Varney]

Originally Posted by Jose A. Garcia

Going back to the optical part of the camera, I'd like to know where to buy very sharp c-mount lenses. Don't get me wrong, I like the soft movielike look the camera has now but when the adaptor is added, the image will pass through 3 lenses (c-mount, achromat and 35mm lens) and the ground glass so if final image is a bit soft I want the 35mm lens to be responsible for that. The rest must be as sharp as possible.

I don't care if the c-mount lens I choose is a second hand one as long as it's very sharp. In fact, it will be much cheaper if it's used.

Where can I look for it?

Check out this thread, it may have some good information for you: http://www.dvinfo.net/conf/showthrea...hlight=c-mount

Originally Posted by Jose A. Garcia

Please, i want to test my debayer algorithm ;)
(in fact, the best would be to have the same sequence in bayer and debayered by micron so i can compare... it might be difficult but there is no point to continue to work on my algorithm if it's bad :))

What kind of debayering algorithm are you using? (spline, bicubic, etc.)Also I would love to see the results if possible.

[Ivan Hamer]

Has anyone managed to obtain the Micron sensor datasheet? I created an account on their site and asked for the NDA, but no one has contacted me yet.

Jose, have you seen this page regarding the lens: http://www.micron.com/innovations/imaging/lens ? They have some useful info there as well as few suppliers listed.

[Jose A. Garcia]

Hi Ivan,

Thanks for the link. Yesterday I uploaded all datasheets, manuals and sample codes that came with the board. Page 10 of this thread.

[Ivan Hamer]

Originally Posted by Jose A. Garcia

Hi Ivan,

Thanks for the link. Yesterday I uploaded all datasheets, manuals and sample codes that came with the board. Page 10 of this thread.

Jose, I looked at the file you uploaded, but it seems sensor datasheet is not there. I looked at all the pdf documents. The datasheet should be something like the document at http://download.micron.com/pdf/produ...31_5100_PB.pdf but with a lot more information (registers, timing, etc).

[Jose A. Garcia]

Ok, I'll send an email to Micron asking for the sensor complete datasheet.

[John Wyatt]

Jose -- what is the reason fixed fps speed cannot be set (or if set, cannot be maintained)? With the Sumix, setting say 25 fps would produce a clip whose properties showed an actual frame rate of say 24.96 fps or some other fractions different from the ideal. Because the RAM-recording clips were quite short, the discrepancy was not great enough for an accumulation to effect sound sync. What sort of discrepancy are you getting from the ideal?
John.

[Jose A. Garcia]

Well, the main problem is that I don't have an option to set fps. Framerate depends on the resolution, system clock, gain, shutter... But nothing more. You cannot program framerate.

I mailed Micron asking if it would be possible to upgrade their program by adding an option to set framerate. They didn't answer yet but I don't think they'll do it. That's why I need someone to help me out with this. I need a tool to control all aspects including fps. If you read the sensor datasheet it says framerate is in fact programmable. I just don't know why they haven't included that option.

As I said, I want to stay with this board. I really like it. So now I'm just waiting for someone who can write an application to control the sensor and record the clips.

As for what you said about RAM recording, I can record 2K AVI Debayered to RAM and RAW debayered to disk in realtime with an almost continuous framerate (between 25 and 26fps) with Micron software.

[Take Vos]

Originally Posted by Jose A. Garcia

Well, the main problem is that I don't have an option to set fps. Framerate depends on the resolution, system clock, gain, shutter... But nothing more. You cannot program framerate.

That sounds the same as with an IIDC camera. The framerate is depended on the amount of firewire bandwidth you want to be used.

But it is possible to trigger the start of a frame externally. I want to use a 1:2000 frequency divider (maybe a simple PIC processor), clocked to a 48000 Hz digital audio word clock.

Maybe that would work with your board as well?

[Jose A. Garcia]

Take, I must admit I'm a bit lost in terms of pure hardware and coding. Anyway if you want me to test options to get those fixed 24fps, just tell me what to do and I'll do it. From what I know about the sensor, I think it's possible to fix framerate via software though. I read it in the datasheet.

I guess it's not so easy but, would it be possible to develop a tool to control the board and record bayer clips? Or maybe adapt you Boom Recorder? It would be perfect if you could do it.

Thanks.

[Jamie Varney]

Originally Posted by Ivan Hamer

Has anyone managed to obtain the Micron sensor datasheet? I created an account on their site and asked for the NDA, but no one has contacted me yet.

Same here, I have not received a single email or phone call from Micron. Also Digikey sells the sensor so I emailed them and asked for the datasheet, the response I got just told me to check the part number... I was not sure what they meant by this so I emailed them back verifying the part number, but I have received no response. However; I did manage to get the full datasheet for the MT9T001 sensor from the digikey site, and I assume that a lot of the information is the same.

According to this data sheet the only way to adjust your frame rate is by changing the vertical and horizontal blanking times.

Don’t take this as gospel but according to my math (which very well my be faulty) to get 24fps at 2048x856 with a 96Mhz pixel clock you would want a Horizontal blanking of 21 and a Vertical blanking of 1093. I chose the minimum number allowed for the horizontal blanking to make my math simpler, so many other combinations are possible.

So Jose if you can use the Micron software to write directly to the registers (assuming the registers are the same as on the MT9T001) you will want to do the following:

Write:
0x0015 to address 0x0005
0x0445 to address 0x0006

Be sure to record the values that are all ready there are first so you can change them back later!

One more disclaimer: I am not positive that this is correct; this would be a lot easier with the proper datasheet! :-(

Edit: Here is the equation as I understand it from the datasheet (Trust me, the datasheet is not this straight forward.)

(((HRes*(VRes+Hblank))+(Vblank*(VRes+Hblank)))*(1/Pixel Clock) = Frame Period
So to get the above numbers I use:
(((856*(2048+21))+(1093*(2048+21)))*(1/96000000)) = 1/24

Also, does anyone out there know if there would be a point to using a lager Hblank and a smaller Vblank? It seems to me that by keeping the Hblank as low as possible it would help to reduce the rolling shutter, but I am not positive about that.

[Jose A. Garcia]

Ok... It's possible to change every single register using DevWare from Micron. I'm just a bit afraid to do it, that's all. I'll see if I can get the datasheet for the MT9P031. Anyway I supose I can always reset the sensor to original settings...

Thanks Jamie!

[Take Vos]

Originally Posted by Jose A. Garcia

Take, I must admit I'm a bit lost in terms of pure hardware and coding. Anyway if you want me to test options to get those fixed 24fps, just tell me what to do and I'll do it. From what I know about the sensor, I think it's possible to fix framerate via software though. I read it in the datasheet.

I guess it's not so easy but, would it be possible to develop a tool to control the board and record bayer clips? Or maybe adapt you Boom Recorder? It would be perfect if you could do it.

Is there not a connector on your test board where you connect the tricker?

As for Boom Recorder, I am still working on getting my own camera to work.

I am still not certain what is wrong with my camera, but the reseller doesn't really want to help me, stating that it is normal that it looks like crap if you use gamma correction. So I will have to design an other way of compensating for it.

From the specification of the sensor, it says that a pixel should be more than 6% off, compared to its neighborhood pixels at 70%, before it is called hot or cold. I am going to measure this as well.

[Steven Mingam]

Originally Posted by Jose A. Garcia

Ok... It's possible to change every single register using DevWare from Micron. I'm just a bit afraid to do it, that's all. I'll see if I can get the datasheet for the MT9P031. Anyway I supose I can always reset the sensor to original settings...

The registers need to be set each time you power the sensor anyway, so if you do something wrong, just switch off the camera ;)

I took a look at what you got from Micron, they have a pretty neat library for handling their sensors and very well documented... Should be a breeze to program something (and there is a lot of examples source code so you don't have to start from zero).

And thanks for the raw file, my avisynth filter work quite well, but at half the frame rate, so i've some room for improvement here...

Btw, thanks to Juan to point me to some pretty interesting and cheap hardware dev kit, i think you can build a usb/ethernet camera head for something like 500$ (or less, depending on the price of the sensor board). Some software developpement is needed but nothing insurmountable...

[Jose A. Garcia]

Hey, that sounds great! So for now we can shoot in raw and debayer in post using AviSynth. Perfect! That's a huge step forward! Now he have no time limitations cause raw capture can be done direct to disk in realtime. How do you read the raw files? Is it possible to have a copy of your AviSynth script? We could also modify it so it debayers and encodes to a lossless codec (JPEG Lossless using FFDSHOW i.e.) to save disk space.

On the other side, you say it's quite easy to develop software for the demo board. The problem is that I don't know a thing about coding. It'd be great if you could help me with that. I just need a very simple tool to control all basic aspects (including fps), RAW capture and that's all really.

I mailed Micron and asked for another week for testing. If everything goes ok, I'll probably keep the board but I'm also interested in your usb/ethernet camera head for about $500.

Good news! I've got the MT9P031 complete datasheet! I'm attaching it to this post.

[Steven Mingam]

There is a plugin named "RawSource" that do perfectly the job, i'll give you everything you need to test it later, i don't have a copy of my plugin here.

For the camera, well, the dev board is 89$ or less (!!) and has everything you need to interface CMOS censors (and i read about a successfull MT9Txxx interfacing) so the price depend of the camera board (325$ here when they had it or 289$ at digi-key...)
But like i said previously its only "theorical"... there is quite some work to get it running...