Hacking the Kodak Reels 8mm Film Digitizer (New Thread)

[0dan0]

Hi @0dan0 -- I have a couple observations / questions about the ISO / exposure algorithm.

v7.1 - v7.5: During capture with my 'C' unit, the highest ISO / exposure that I observed was ISO 200 / ~5970µs. I never observed an ISO of 400 during capture, even with a black image. Is that behavior consistent with your expectation / experience?

v7.6: During capture with my 'C' unit, the highest ISO / exposure that I observed was ISO 100 / ~5984µs. I never observed an ISO of 200 or 400 during capture, even with a black image. Is that behavior consistent with your expectation / experience?

I understand that you're aiming for the lowest practical ISO for the film's density, but I'm surprised that none of the thousands of feet of film that I've scanned with v7.1+ has triggered neither your highest coded ISO nor an exposure time exceeding 6000µs. If that is by design, then no worries... I just want to confirm that my unit isn't underexposing images due to a hardware malfunction or firmware bug.

The code can go to 400 in preview, but this might be bug. Use the histogram to judge the exposure.

 

[rdesros]

@0dan0 Quick update on version 7.6: I’m now getting a steady 25–27 Mbps with the stock lens. Sharpness set to -0.5. There’s still a bit of jitter at the bottom of the screen occasionally, but overall the capture quality is pretty good. This is using version A of Kodak Reel. Thx

 

[P-car]

fantastic!!

Ok, so to get 25-27 Mbps, I just set it to the lowest possible number - 15 for example - and let the also do the rest, correct?

 

[rdesros]

fantastic!!

Ok, so to get 25-27 Mbps, I just set it to the lowest possible number - 15 for example - and let the also do the rest, correct?

Yes. I forgot to mention that Qp is set to the lowest value.

 

[0dan0]

Bit-rate is depended on the Qp value. Lower Qp, higher bit-rates. If you values below 22, you adding risk of capture failures. Rare now, but it can happen.

 

[0dan0]

But I noticing, V7.6 doesn't want to go below Qp 20. Looking into that. It is Type A bug, only.

 

[rdesros]

But I noticing, V7.6 doesn't want to go below Qp 20. Looking into that.

Yeah, I noticed that too.

 

[rdesros]

@0dan0 Quick update on version 7.6: I’m now getting a steady 25–27 Mbps with the stock lens. Sharpness set to -0.5. There’s still a bit of jitter at the bottom of the screen occasionally, but overall the capture quality is pretty good. This is using version A of Kodak Reel. Thx

This is with Topaz Video AI enhancement applied.

 

[rdesros]

View attachment 25416
This is with Topaz Video AI enhancement applied.

 

[0dan0]

Are you reapplying grain in Topaz, as this are pretty nice / gentle enhancements. Can you share your settings?

 

[rdesros]

Are you reapplying grain in Topaz, as this are pretty nice / gentle enhancements. Can you share your settings?

 

[0dan0]

I got Type A running at Qp 16 again, outputting 45Mbs. Updating builds now.

 

[rdesros]

I got Type A running at Qp 16 again, outputting 45Mbs. Updating builds now.

Switching back to ISO 50 seems to be improving encoding by cutting down noise, which usually gets in the way of encoders. In the next update, hitting 45 Mbits sustained might not happen, but landing around 28–30 Mbits would still be fine. After that, Topaz can help enhance the image and fill in any gaps with some grain.

 

[0dan0]

v7.6.1

Bug fixes only.

- Qp rate control below 20 was fixed on Type A & C (B was okay)
- Now supports up to 400 ISO during encoding (not sure if this is a good thing, but try it.)