AMATEUR PHOTOGRAPHY. 



243 



a 654 inch focus lens will not take in as 

 much as a 4x5 plate with same lens." 

 Another tells me that a zYa^aVa plate used 

 with a 2 J A^4 X A l ens °f &A inch focus has 

 practically the same angle of view as a 

 3>4 x 4/4 plate use in a 4x5 camera of 

 same focal length. 



Now if this be true, and also if what 

 Mrs. Porter says be likewise true, I am 

 prepared to prove a remarkable truth; 

 namely, a picture taken on a 4x5 plate 

 with a 6% focus lens (which has not 

 proper perspective as Mrs. Porter states) 

 can be made to have the proper perspec- 

 tive by simply trimming it down to 3%x 

 4 l A inches! I am free to admit I am not 

 well up in this subject and perhaps the 

 last result is not so wonderful as it seems 

 to me. T. A. Wilson 



Waverley, Nova Scotia. 



ANSWER. 



The above was referred to the Ameri- 

 can representative of C. P. Goerz. He 

 replies as follows: 



The statement that the focus of the 

 lens should be 1^2 times the length of the 

 plate is correct in a number of instances, 

 particularly when the lens is used exclu- 

 sively for landscape purposes; but for 

 average photographic work, as portraits, 

 snapshots of street scenes and indoor 

 work a lens equal in focus to the diagonal 

 of the plate is more desirable. We gen- 

 erally nse 6 inch lenses for 4x5 plates, 

 and 4^2 or 5 inch lenses for 3^x4^4 

 plates. The statement made by Mr. Wil- 

 son's correspondent about the 6yi inch 

 lens giving the same angle on different 

 sizes of plates is entirely erroneous. The 

 angle which the 6 l /i inch lens would in- 

 clude on a 3^4x4^4 plate must of course 

 be smaller than that which the same lens 

 would include on a 4x5 plate. So far as 

 the perspective is concerned, it is true 

 that, while the perspective of a 6 inch 

 lens on a 4x5 plate would be considerably 

 exaggerated, such exaggeration wou r id 

 disappear when trimming the 4x5 image 

 down to 3^/4x4^4, for the simple reason 

 that the exaggeration of the perspective 

 makes itself noticeable toward the mar 

 gin of the plate. The theory that a lens 

 should have a focus equal to i]/ 2 times 

 the length of the plate had its origin in 

 the old conudition of affairs, before the 

 modern lenses were constructed. It was 

 then necessary that the lens should be of the 

 before mentioned length of focus in order 

 to make it cut the plate in a satisfactory 

 manner. That is why photographers se- 

 lected 5x7 lenses for 4x5 plates or an 

 8xto lens for 6y 2 x8y 2 plates; but owing 

 to the greater perfection of modern ob- 

 jectives this is no longer necessary. It is 

 even preferable that a lens not longer 



than required to give the proper definition 

 over the plate should be used, as with the 

 increased focus the depth of focus reduces 

 when the relative openings remain alike. 

 Thus it is not possible in a general way 

 to state which focal length is best for a 

 given size of plate, as the nature of the 

 work which the lens will be used for 

 covers this point exclusively. If it were 

 desired to make an interior photograph, 

 say, of a room or hall on a 6^2x8^ plate, 

 I should use a lens not longer than 6 

 inches in order to include the adequate 

 angle; if on that same plate I wanted to 

 make a snapshot of a team of baseball 

 players I should use a 9 inch lens; if I 

 intended to photograph a landscape which 

 obtained its beauty from a range of far 

 off mountains I might use a lens of 18 

 or even 24 inch focus ; and for a portrait 

 on the same size of plate I would prefera- 

 bly use a lens of 11 or 12 inch focus. 

 Many of these, of course, can be compro- 

 mised and, at the expense of the possible 

 maximum perfection, an average may be 

 found which will give fairly satisfactory 

 results for a number of combinations; 

 but when absolutely the best result in 

 either of these different classes of work is 

 wanted only lenses of widely different 

 focal lengths will produce it. 



CAMERA NOTES. 



GENE S. PORTER. 



Photographers who wish to excel or to 

 sell their photos should do only honest 

 work. You may succeed once with a pub- 

 lisher on some trick work, but it is a 

 success you will be sorry for later, when 

 the people who live and work in the woods 

 find you out, for they are the sharpest of 

 critics. They know the laws of nature and 

 the habits and cunning of wild things. They 

 know where the fox hides and the rabbit 

 burrows; how the mink fishes; how the 

 vireo builds her pensile purse of lint and 

 lichen; and Why the king crow stands 

 sentinel over his feeding flock. They also 

 know that not one of these or their 

 kindred will change their habits to ac- 

 commodate any photographer. Some fake 

 workers have been successful in getting 

 their exceeding curious interpretations of 

 nature before the public only to gain ridi- 

 cule. 



A year ago editors with no knowledge 

 of the woods or of pictorial photography 

 felt themselves capable of passing on and 

 accepting work that the veriest amateur 

 in wood lore and field photography could 

 have told at a glance to be a fake. As 

 burnt children dread fire, so now these same 

 editors, smarting under the disgrace of ex- 

 posure in frauds to which in all probability 

 must of them were innocent parties, refuse 

 to look at a, picture unless accompanied 



