Sometimes I have really problems to keep my water bath at desired temperature. So it would be lot easier to use current room temperature. But that raises a question. How accurate are temperature/developing time conversion charts - I use Ilford's chart as an example because it is well known (http://www.digitaltruth.com/devchart.html ). For example, if I have calibrated my developing times for temperature of 24°C, can I trust that result is almost identical at 20°C if I just adjust development time using chart? Is there any test lying on the net?