54 The Microscope 



it is only necessary to activate the shutter. Nothing else need be moved 

 and regular visual observation need not, even momentarily, be inter- 

 rupted. 



The only disadvantages of this method are those of reflex cameras. That 

 is, the lack of interchangeable oculars limits the flexibility of the system. 

 Even this may be avoided, in the particular instrument shown, by substi- 

 tuting a monocular body for the film camera and rigging a direct camera 

 on top of this. 



TAKING A PHOTOMICROGRAPH 



By now the reader should have a clear understanding of the principles 

 of microscopy, the principles of photography, and the equipment avail- 

 able for photomicrography. With these in mind, there is little left to be 

 discussed. 



p 



I 



m 



Fig. 67. Contact print and enlargement of 35-mm roll-film negative taken with the 

 apparatus shown in Fig. 66. The little picture as reproduced is at a magnification of 

 about 200. The large picture is at a magnification of about 1,000. The object 

 is the bacteria Serratia tnarcescens stained with celestine blue B to show the "nuclear- 

 like" granules. 



