Convergent Design Nano Flash & Z7 ?

[John Quick]

Has anyone seen a comparison of Z7/Nanoflash and EX1/Nanoflash on good monitors? I'm expecting the latter will be better, but how much better?

[Dan Keaton]

Dear John,

That is a great question.

We have not compared these two cameras (with a nanoFlash on each).

Maybe someone with these cameras (and a nanoFlash) could comment.

What is nice, is that many modern cameras produce a good or great image, and have a method, such as HD-SDI or HDMI to allow a high-quality recorder, such as our nanoFlash to record these 4:2:2 images.

[Ronnie Martin]

Ok I am convinced that the Nano Flash is the way to improve the Z7/270.
Just how does it work? With the 270 do you still have to have the tape in the camera to shoot with the Nano flash?

Can you shoot with both the Tape and the Nano Flash for a back up?

What about the compact flash card already on the Z7/270? Do you remove it?

Does the Nano Flash make the Z7/270 a 1920x1080i camera?

I assume that if the tape is in the camera along with the Nano Flash the tape captures 1440x1080i while the Nano Flash captures 1920x1080i. Is that correct?

Thanks

Ronnie Martin
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[Steve Phillipps]

The only thing the Nanoflash really changes, and where the improvement lies, is in the codec, giving much lower compression (ie 160 mb/s vs 18 mb/s or so). It won't give you any more resolution or dynamic range or anything else. But it should still make a huge difference as it's the codec where the HDV cameras are probably weakest.
You can trigger the Nano from the camera which will then roll the tape as well, or directly from the Nano unit.
You also won't get overcranking (ie slow motion) as this requires a 50P or 60P input (ie from 720 mode).
note: I don't have one so the above comments are just from my understanding, I stand to be corrected but think it's right.
Steve

[Alexander Timanov]

I beleive you're right Steve.

The only way to have all questions answered is to test the Nano flash device with S270/Z7 and post the results. It is what I'm waiting to happen before buying Nano flash. I know that the Nano flash is the only way to improve quality of the video with these camcorders.

Dan Keaton from Convergent Design explained me that HD-SDI is always 1920x1080. But according to my calculations the sensor in S270/Z7 is not 1920x1080, or maybe I'm wrong? I beleive that the sensor scans images and then stretches them to 1440x1080. How it produces 1920x1080 via HD-SDI? Stretching? But what is the physical resolution of the sensor then? Can someone comment on that please?

Thank you
Alex

[Ronnie Martin]

I guess that you are right we will not know the answers to these questions until someone gets a Nano Flash and then does some tests with the Z7/270

What about the compact flash card already on the Z7/270? Do you remove it?

Does the Nano Flash make the Z7/270 a 1920x1080i camera?

I assume that if the tape is in the camera along with the Nano Flash the tape captures 1440x1080i while the Nano Flash captures 1920x1080i. Is that correct?

Thanks

Ronnie Martin
Page 1

[Steve Phillipps]

According to the Sony spec the Z7 has only 1 million pixels, compared to 2 million for their higher end cameras and the likes of the EX1/3. Quite what that means for resolution I don't know.
I think the 1440x1080 comes from the HDV codec, that's its resolution, in the same way that HDCam is 1440x1080 and the pixels are stretched (ie non square) to make it 1920x1080. The same is true of Panasonic's DVCPro HD which is 960x720 or so and stretched into 1280x720.
Most of the newer codecs are going "full raster" so Panny's AVC Intra is full 1280x720 and XDCam HD and EX are both 1920x1080. As is the Nanoflash.
Steve

[Uli Mors]

Its simple.

The Clearvid Cmos uses a non Full HD grid , RGB shifted to each other (pixelshift), interpolated and recorded to 1440x1080.
This grid again is stretched when output via HDMI or HD-SDI or HDanalog out (like HDCAM does too).

The bargain of the nanoflash is that you dont record the 1440x1080 with only 25mbit/s but the NONCOMPRESSED signal (pixelshifted CCD -> 1080) with much higher bitrate, leaving compression artefacts behind.

I am sure the results are better than the HDV recording, but you dont get higher resolution that what is generally capable by the sensor.

BTW: Clearvid is a great technology. Its not full HD but each pixel is bigger and therefore 1/3" can be very lightsensitive (-> Z5, Z7).

ULI

[Alexander Timanov]

I assume that the results are visually indistinguishable. (ie 1920x1080 from S270/Z7 with a nano flash and EX1/3) Only the test chart could show some difference in resolution. But using ClearVid Technology along with Nano Flash would give fantastic results.

Alex

[Steve Phillipps]

Alexander, do you mean that the Z7 and EX3 will look the same? If so I think you're very much mistaken. The EX3 has full 1920x1080 chips for a start, and they're 1/2".
Steve

[David Heath]

Originally Posted by Steve Phillipps

According to the Sony spec the Z7 has only 1 million pixels, compared to 2 million for their higher end cameras and the likes of the EX1/3. Quite what that means for resolution I don't know.

Quite right, it's 1 million pixel chips. The arrangement is complicated as the rows are aligned on the diagonal, but best thought of as two interleaving 960x540 matrices. That means they are easily processed in a 1920x1080 processor, but although the output of that is 1920x1080 pixels, the reolution won't be as high as that. 1440x810 is the generally accepted figure. There's also the progressive/interlaced matter to consider, but this chip arrangement can be processed to interlace very well.

I think the 1440x1080 comes from the HDV codec, that's its resolution, ...

Yes, for HDV, you record 1440x1080 pixels - so the 1920x1080 gets scaled down horizontally. It shouldn't lose any resolution - it wasn't there off the chip - so the HDV subsampling suits these chips very well for resolution.

Use a nanoFlash and you then record the full 1920x1080 off the processor, but don't expect it to be any sharper. The advantage the nanoFlash WILL give (cf HDV) is milder compression, and keep a bit more of the vertical chroma resolution. But I wouldn't expect an S270/nanoFlash to look as good as an EX - the EX won't just give 1/2" chips and full 2 megapixel resolution, it will also give better than HDV compression as well.

[Alexander Timanov]

Originally Posted by Steve Phillipps

Alexander, do you mean that the Z7 and EX3 will look the same? If so I think you're very much mistaken. The EX3 has full 1920x1080 chips for a start, and they're 1/2".
Steve

No Steve, I didn't mean that. I thought that shooting with S270 and nano flash would give very good results. For example using S270 with Nano flash and EX1 without it during multicam shooting would give almost indistinguishable results for a viewer.

Alex

[Steve Phillipps]

I think you're still wrong though Alexander, I suspect that they'd be pretty different as the EX1 has got twice as many pixels.
Steve

[Dan Keaton]

Dear Friends,

If a camera is in 1080 mode, then the HD-SDI output is always 1920 x 1080.

This is great, as the nanoFlash can then record full raster 1920 x 1080, which takes a huge load off of the computer that will perform the editing, as it will already be 1920 x 1080. The processs of converting 1440 x 1080 to 1920 x 1080, in the computer, is completely eliminated.


A computer has a lot of work to do to convert 1440 x 1080 to 1920 x 1080. There is no "magic instruction" that does this; it is a rather intensive computer function to do this.


The beauty of HD-SDI always being 1920 x 1080 is that all cameras have to do this; and they do it in hardware instead of software, so it can be accomplished on the fly.

Dedicated, custom built hardware usually is better than using a general purpose computer for the same purpose.

[David Heath]

Originally Posted by Steve Phillipps

I suspect that they'd be pretty different as the EX1 has got twice as many pixels.

Originally Posted by Dan Keaton

If a camera is in 1080 mode, then the HD-SDI output is always 1920 x 1080.

Yes Dan, but that's not the same as the picture having a true 1920x1080 resolution if the chips aren't 2 megapixel. It's as Steve says - it's only got half the pixels of such as the EX, so you can only expect about 1440x810 resolution, no matter what the recorded raster is.

I don't doubt a Z7 or S270 will be improved by adding a nanoFlash - it gives a better codec - but the question here is whether the combo will be better than a straight EX. I doubt it will be - for the reasons Steve and I give above.

And the EX gives a 1920x1080 codec straight from the camera, so same here as the nanoFlash.