In Wildest Africa -* 



exposure. Experience alone can enable you to judge 

 what exposure to allow. When you have got your 

 shutter to the correct speed and chosen the correct 

 diaphragm for your lens, you must get into the way of 

 using the camera as quickly and deftly as your rifle. 



In this way, just as in shooting, you will learn to allow 

 for the movements of the object you are aiming at you 

 will let your camera move accordingly. This needs a lot 

 of practice. At the period when I was using the Goerz 

 apparatus, a large number of similar cameras of all sizes 

 were returned to the manufactory by practical photographers 

 as unuseable. This shows how difficult it is to form any 

 opinion as to the possibilities of the telephoto lens without 

 going in for thorough and repeated experiments. 



It is only on rare occasions that you are able to use a 

 stand-camera for photographing objects at a distance. In 

 most cases you must shoulder your photographic gun, and 

 it may be easily imagined what dexterity is required for its 

 proper management. In -following up the moving object 

 with your lens you inevitably make the background some- 

 thing of a blur. You are apt at the same time to under- 

 expose. The change of diaphragm and the modification 

 of the speed of the shutter involve; many failures. The 

 telephoto lens has this advantage, however, that you can 

 generally get good results with it at a hundred paces. In 

 the case of birds on the wing, either rising or flying past 

 you, you have to get into the: way of reckoning the 

 distance a difficult matter. Of course you must always 

 have the sun more or less behind you. The conditions of 

 the atmosphere in the tropics' the shimmering waves of 



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