Cameras, Lenses, and Shutters 35 



if we have never used one before, we had better 

 let some one select our instrument that has some 

 knowledge of them, and not depend upon the 

 advice of the dealer. Afterward, we should be- 

 come thoroughly acquainted with all its various 

 movements and how they affect the image before 

 we attempt to make any exposures with it, for by 

 so doing we will find that we can work quicker 

 and to better advantage when we do begin, and 

 will make fewer failures in consequence. 



Tripod cameras are of two types : the long and 

 the short focus, that is, those having a long exten- 

 sion of bellows and those whose bellows are much 

 shorter. For nature workers the former is the 

 type that should always be used, as with it we are 

 enabled to obtain a much larger image, in other 

 words, work closer to our subject, than with the 

 short focus camera. The ones that have an 

 extension of bellows both at front and rear are 

 the most convenient, as they allow of being fo- 

 cussed either from the back or front as we please, 

 besides beingr much more ritjid than are those 

 whose bellows extend only in the front. 



The swing-back is an essential feature of the 

 modern camera. It is a device by which the 

 back, holding the plate-holder, is allowed to swing, 

 either vertically or horizontally, to a considerable 

 angle. Let me explain the advantages of this 

 contrivance. The nearer the camera is to an 



