As the subject of metering pyro negatives - or using a densitometer with pyro negatives - is a constant matter for muttering, we have decided to produce a meter designed for pyro:
The meter won't be shipping until mid November. So far there is only the one pre-release web page for information on the meter.
More information will be supplied as it becomes available.
We will have an application note on metering pyro negatives in general on the web site before the meter releases. Hopefully also the instruction manual - usually the last thing that gets done...