BOTANICAL PHOTOGRAPHY 169 



H2O 1,250 c.c. 



Metol 1 g. 



Sodium sulphite 15 g. 



Hydrochinon 4 g. 



Sodium carbonate 15 g. 



Potassium bromide 1 8 g. 



There is a relation between the length of exposure and the time of 

 development. Suppose that with a good negative an exposure of 10 

 seconds with 2 minutes of development gives the best results. Then an 

 exposure of 5 seconds, with 4 minutes of development, or an exposure of 

 20 seconds with 1 minute of development, should yield prints nearly as 

 good. Too long an exposure gives dark, unsatisfactory prints; while, 

 with too short an exposure, the paper becomes gray or spotted in the 

 effort to get pictures by prolonging the development. 



With uneven negatives, the exposure can be controlled, more or less, 

 by holding a suitably shaped piece of cardboard between the lens and 

 the paper, keeping the cardboard in motion .to avoid sharp contrasts. 



Transfer from the developer into the stop. Here again, there can be 

 some control, because — with the trays close together — part of the 

 print can be slipped into the stop, while the rest develops a little 

 longer, so that a sky with clouds can be developed after the develop- 

 ment of the foreground has been stopped. By applying the stop with 

 a tuft of cotton, good prints can be secured from negatives which would 

 yield only flat prints without such treatment. 



Then transfer to hypo. Many prefer a plain fixing bath: 



Water 1 liter 



Hyposulphite of soda 250 g. 



It does not keep well and must not be used if it shows the least 

 brownish color. Make it fresh every day. 



A single print would be fixed in 15 or 20 minutes; but prints are al- 

 most always piled, one on top of another, in a tray of hypo. They 

 should be moved frequently, taking the one from the bottom and put- 

 ting it on top. With such movement, half an hour, or even an hour, 

 is not too long. 



Then wash in running water for half an hour, or even an hour. If 

 the prints are in a sink, a rubber tube can be fastened to the faucet, 

 and one can pinch the end of the tube so as to spray the prints. In this 

 way, prints may be washed thoroughly in 15 minutes. The most ex- 



