And don't forget whiteprint/bluelines (diazo): https://en.wikipedia.org/wiki/Whiteprint https://en.wikipedia.org/wiki/Whiteprint I have worked with them, many

And don't forget whiteprint/bluelines (diazo): https://en.wikipedia.org/wiki/Whiteprint https://en.wikipedia.org/wiki/Whiteprint I have worked with them, many years ago, and even with modern (for the time) ventilated developing chambers, using the ammonia was really terrible.