I think we will only get a MSDS if they bring it over to the US for sale, I am not sure of what the equivalent would be for Germany or the UK, but I think there maybe be something of that sort to outline whatever is in their solution. Two bath developers are nothing new and many work quite well, but so far this one seems to be lots of hype that I hope it lives up to.
Thanks for this explanation---it's something I've long wondered about. If I understand correctly, this is basically the speed that follows from the principle that the most you can do is develop to completion, right?
Originally Posted by Photo Engineer
I imagine the threshold speeds of common materials (like the one that starts with a T and ends with an X400) must be known in the industry---is there any way for us outsiders to find out what they are?
You can find out the minimum exposure it takes to produce a detectable change on the negative (first exposure that provides density above film base density) in your camera + developing combination (whether push or not) using a densitometer.
Dan is correct.
Using a step scale, such as a Macbeth Color Checker, you can expose correctly, and then figure out the threshold speed just by looking at the curve from this. Then, assuming ISO 400 from the straight line, you can guesstimate the maximum speed by the method Dan has described. Just look at the first detectable image and then measure the number of stops that this takes place at, vs the mid scale.
This is the threshold speed and is the max that can be obtained from that film by any means.