I was going through my old Focal Press Encyclopedia and was looking at the M.-Q. charts and found an interesting anomoly. 2 different recipes each for Kodak D-72 and for Gevaert G.201. As follows . . . Gevaert G-201 Warm Water - 500cc for both Metol - 0.4g and 1.5g Hydroquinone - 1.5g and 6.0g Sodium sulphite, anhyd - 12.0g and 50.0g SOdium carbonate, anhyd - 8.0g and 32.0g Pottasium Bromide - 0.5g and 2.0g Add cold water to make - 1L for both I just noticed that the second recipe is nearly 4 times the strength of the first. Is this a concentrate? Kodak D-72 Warm Water - 500cc for both Metol - 0.5g and 1.6g Hydroquinone - 2.0g and 6.0g Sodium sulphite, anhyd - 7.5g and 22.5g Sodium carbonate, anhyd - 11.0g and 34.0g Potassium bromide - 0.3g and 0.9g Add cold water to make - 1L for both And I have just noticed that the second recipe here seems to be roughly three times the strength of the first. So same supposition. Concentrate? Also, both first recipes are listed as standard contrast. Both second recipes are listed as, simply, 'Contrast' developers. Just curious but would love your thoughts and ideas.