ANIMAL PHOTOGRAPHY 19 



canoe, from a blind or by stalking? On the 

 consideration of all these points depends the 

 selection of a proper outfit. Generally speaking, 

 the reflex type of camera is almost a necessity 

 when good results are desired. Its size must 

 depend on what you can use under the existing 

 conditions. A four by five, or even a quarter plate 

 size when light weight is called for. The five by 

 seven, or the half plate, if it can be managed. These 

 larger sizes are far more satisfactory, but are, of 

 course, more expensive, more bulky and much 

 heavier, and stalking with them is made very much 

 more difficult. The very rapid lenses, that is, those 

 working with an aperture of F. 4.5, or thereabouts, 

 have so little depth of focus that it nearly always 

 means cutting them down to about F. 6 in order 

 to obtain even fair depth. So the extra weight is 

 being carried to very Uttle purpose, such as a quite 

 occasional exposure under poor light conditions. 

 F. 6 is quite large enough for most practical pur- 

 poses. The new types of low and usually single- 

 powered telephoto lenses promise great things. 

 They are being changed so frequently that before this 

 appears in print some new device may be invented 

 which will completely revolutionise everything. 

 The chief (and almost only) advantage possessed 

 by these types is that with a camera having only 

 a short draw (of bellows) you can use a lens which 

 has approximately an equivalent focus of twice the 

 length of bellows. Against this, if they work at 

 an aperture of F. 5 or 6, there is the disadvan- 

 tage of size, both in diameter and length, which 

 makes them somewhat cumbersome. If you can 



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