digitalFAQ.com Forum - Panasonic DMR-ES10 PAL brightness fluctuations?

Supposing that the AGC of the DMR-ES10 is the culprit, you could try the same approach that this "gleitz.info" german forum thread discusses, where comment #10 provides the best solution:

https://gleitz.info/forum/index.php?...405#post462405

The idea is to add a resistive divider (preferably with a pi circuit as comment #10 shows, to offer the proper termination for the video signal) between VCR and DMR, to the composite video cable or the luma signal in case of using a S-Video connection (chroma signal doesn't need attenuation). This reduces the signal level just enough to fall below the activation threshold of the AGC, disabling it completely. In the thread this is used to legalize extremely high values of luma that the Panasonic DMR AGC clips to white. The connections would be as follows:

VCR -> Resistive divider -> DMR-ES10

I think this idea could work, although I haven't tried it yet, because I have the same problem with my Panasonic. For completeness, I am attaching the comment #10 from the linked thread, originally written by user "Loetkolben" and translated to english, together with the attached images:

Quote:

Hello everyone,

In order to properly digitize Video8 and Hi8 cassettes, I bought a Blackmagic Intensity Pro and a Panasonic DMR-EH495. Unfortunately, as I feared, the luminance channel is noticeably overdriven. For the best possible quality, only transmission via S-Video is possible. So I had to bite the bullet and get an S-Video cable. A simple voltage divider with a potentiometer can be problematic because the video signals are transmitted with 75 ohm input and output impedance. These are signals with several megahertz that are easily reflected if the impedance is poorly matched and cause visible image errors. The solution is an attenuator designed for 75 ohms . I built it as a Pi circuit with 0805 resistors on a strip grid board to keep unwanted inductance/capacitance as low as possible:

Attachment 18489

Attachment 18490

-5.6dB attenuation (Pi circuit with 2x240 ohms between Y and Y- and 51.7 ohms in series with the luminance signal Y) has proven to be optimal for well-controlled video. There were no fluctuations between the cassettes, regardless of whether they were Video8 or Hi8. All cassettes were played on a Hi8 camcorder. The chrominance channel does not need to be adjusted, it is transmitted with a lower voltage anyway. Despite the reduced luminance level, there are no oversaturated colors. Here is another example: Hi8 still image with waveform display for Y, Cb and Cr:

Attachment 18491

There are still a few isolated peaks in the "forbidden" super-white area - but a stronger attenuation does not reveal any additional image information because these areas of the image were already overexposed when the picture was taken. I tried digitizing with even stronger attenuation. The result was gray highlights and unused resolution of the brightness values.

Even though this thread is already a few years old, maybe this post can help someone to better digitize valuable memories on cassette.