i8 



HOW TO PHOTOGRAPH 



over-exposed, don't waste time in trying to 

 patch up the negative, but expose another 

 plate. 



7. Under-exposure. — There is no cure 

 for this evil: destroy the negative and 

 take another. 



8. Under-Developjnent.— underde- 

 veloped plate is useless. Don't hurry the 

 development, but be sure all possible de- 

 tail has been worked out, and examine the 

 negative for density before the lamp. 



9. Thinness — The negative appears 

 fully exposed and developed, but is too thin 

 to give good prints. In this case try the 

 effect of covering the back with matt var- 

 nish, and print in the shade. Never intensi- 

 fy a negative before trying how it will print. 

 Many a negative that appears too thin will 

 give perfect prints. The negative from 

 which the accompanying illustration of 

 "Palpi of Male Spider" was taken fur- 

 nishes a good example of this. This nega- 



PALPI OF MALE GARDRN SI'inRU. 



live appears a mere "ghost," but prints 

 well and strongly. Had it been intensified 

 it would probably have been ruined. If 

 the matt varnish does not mend matters, 

 the negative must be intensified. There is 

 a choice of intensifiers, but the mercury and 

 silver intensifiers are most generally used. 

 The mercury intensifier is made as follows : 

 A. — Saturated solution of mercuric chlo- 

 ride. 



B. — Liquor ammonise, 10 drops per oz. 

 After soaking the negative in water, it is 

 placed in the bichloride solution until it be- 

 comes uniformly white. If requiring only 

 slight intensification, it must be left in only 

 a few seconds, or it will become too dense. 

 Then wash well for five minutes, when the 

 negative must be placed in B, which will 

 turn the plate to a dark color. With a 

 little experience, this intensifier will be 



