I used Ilford ID-11 Plus in the late 1980's and ha yes I do recall a different smell, so cinnamic acid would make sense. The guy at the camera shop said it made more 'brighter' negatives, and I think the contained information had the anti-silvering/machine processing improvements indicated. I was 'replenishing' by doing the percentage increase in time, small tanks, of nightclub photos mostly shot with flash, and I found I could make the then 1 Quart size last a good amount of rolls.
'I once found a 1980's SDS for it somewhere. If I remember correctly the magic ingredient was cinnamic acid (disulfide) - presumably to help prevent/minimize sludging of dissolved silver in machines. Various compounds were used in developers over the second half of the century for this purpose - also to reduce the risk of dichroic fog - but they eventually became redundant and/or detrimental as emulsions evolved to obviate the need. "
'I once found a 1980's SDS for it somewhere. If I remember correctly the magic ingredient was cinnamic acid (disulfide) - presumably to help prevent/minimize sludging of dissolved silver in machines. Various compounds were used in developers over the second half of the century for this purpose - also to reduce the risk of dichroic fog - but they eventually became redundant and/or detrimental as emulsions evolved to obviate the need. "
