176 DRAWING BY THE AID OF PHOTOGRAPHY [Ch. VI 



right edge up, but with the cover-glass facing the light, the slide 

 toward the objective. 



(2) Translucent drawing paper. If the drawing can be made 

 on the back of translucent paper the specimen is placed on the stage 

 right edge up and with the cover-glass facing the objective. Test 

 with the lettered specimen (fig. 105). 



§ 284. Erect images with an objective and ocular and a 45° mirror 

 or prism. — Place the slide on the stage right edge up, and with 

 the cover-glass facing the objective. The image will be erect on 

 an opaque drawing surface. Test with the lettered preparation 

 (fig- 105). 



Drawings by the Aid of the Photographic Camera 

 and the Magic Lantern 



§ 285. Drawings by the aid of a photographic camera. — The 



photographic camera (camera obscura) gives help for getting pictures 

 of objects in three ways: 



(1) By producing real images which can be traced (§ 286). 



(2) By producing negatives which can be projected upon the 

 drawing paper and traced, or the drawing can be done directly on 

 the print, and all but the drawing removed from the print; or the 

 drawing can be made on the back of the print (§ 288-289). 



(3) By producing large prints for retouching (§ 290). 



§ 286. Real images by the camera. — For drawing with a photo- 

 graphic camera it is a great help to have a frame with a piece of 

 clear glass to use instead of the ordinary ground-glass focusing screen. 

 The tracing paper is stretched over the glass. The object is arranged 

 as desired and placed in a strong light. The camera is then arranged 

 to give the desired view, and the bellows pulled out and the whole 

 camera moved toward or away from the object until the desired size 

 is obtained. This tracing is transferred to the drawing paper in 

 the usual manner and inked in. A camera like that shown in fig. 107 

 answers well; also a copying camera (fig. 108). 



While inking in, and indeed whenever free-hand and optical methods 

 of getting drawings are combined the object should be available for 

 constant observation so that accuracy may be obtained. 



