1 84 HOW TO STUDY BIRDS 



tography, I will give a few hints about some practical 

 matters which have a special bearing on this depart- 

 ment. The main thing we are to try for is to secure 

 clear, sharp, detailed pictures of the wild bird or an- 

 imal in life, as well as of other natural objects, and 

 not the blurry monstrosities which some people are 

 pleased to consider " artistic." Learning the proper 

 length of the exposure will give some trouble at first, 

 but with the help of published tables, or of " ex- 

 posure-meters," this will soon cease to be a problem. 



A developer which works slowly and gives bril- 

 liancy is the most easily controlled and the best for 

 the beginner. Hydroquinone is good to try first, but 

 certainly not pyro, which, though often recom- 

 mended, is dirty and troublesome to handle. Do not 

 take the plate out of the developer when the picture 

 looks best on the surface, but leave it in till the im- 

 age shows clearly through the glass side of the plate, 

 even if the surface picture seems to fade away into 

 utter blackness. Such darkening shows too long ex- 

 posure, but it will only make matters worse to take it 

 out before the image has formed clear through the 

 coating on the plate. 



This over-exposure can be remedied, as under-ex- 

 posure cannot, in the following way, which is worth 

 knowing: If the plate is very black and dense, yet 

 with a clear image, as seen by holding it before a 

 strong light, put it in a reducing solution of red 

 prussiate of potassium and hyposulphite of soda until 

 it thins down to just a good printing density. This 



