192 THE FORMATION 
benefit. When the picture is worth the trouble, a tent may be erected to 
afford a very efficient protection. This is too prodigal of time and energy, 
however, to be practicable under the usual conditions. Flashlight exposures 
on still nights are sometimes feasible, but the disadvantages connected with 
them are too great to bring them into general use. The best procedure is 
to bide one’s time, and to take quadrats, transects, and other detail areas, 
as well as many plant groups, at a time that promises to be most favorable. 
Single plants can often be moved in the field so that they are protected from 
the wind, or so that they are more strongly lighted. Slender, or feathery 
plants. are usually very difficult to handle out of doors. The best plan is to 
photograph them in a room that.is well and evenly lighted, or, best of all, 
in a stable, roomy tent. 
239. The sequence of details. No photographer ever escapes blunders 
entirely. At the outset of his work, the ecologist must fully realize this, 
and accordingly plan a method of operating the camera which will reduce 
the chance of mistake to a minimum. The usual blunders which every 
one makes sooner or later, such as making two exposures on one 
plate, drawing the slide before closing the shutter, allowing the light to 
strike the plate through the slit in the holder, etc., can be all but absolutely 
avoided by a fixed order of doing things. This order will naturally not be 
the same for different persons; it is necessary merely that each have his own 
invariable sequence. The following one will serve as an illustration. As a 
preliminary, the plate-holders are filled, after having been carefully dusted, 
and the slides are uniformly replaced with the black edge inward. It is a 
wise precaution to again see that all the slides are in this position before 
leaving the dark room. This will ensure that.a black edge outward always 
means that the plate has been exposed. The tripod is first set up and placed 
in what seems about the proper position. The camera is next attached to it, 
and the front and back opened. The bellows is pulled out, a short distance 
for views, and a longer one for detail pictures, and fastened. It is necessary 
to move the diaphragm index to the largest aperture and to open the shutter 
at “time.” The next steps are to orient the view or object, and to bring it 
into sharp focus upon the ground glass. The first is accomplished by moving 
the entire instrument, changing the position of the tripod legs, swinging the 
camera upon the tripod, or by raising or lowering the lens front. It is often 
desirable also to change the position of the object on the plate by use of the 
reversible back. In views with much distance, the foreground is brought 
into sharp focus. In close views, especially of quadrats, the swing is used 
to increase the distance for the foreground, and the focus is made upon the 
center. After focusing, the shutter is closed, the indicator set at the time 
