AMATEUR PHOTOGRAPHY. 



343 



lanterVi slide will require attention at the 

 spotter's hand from defects that have made 

 their appearance during its manufacture. 

 As a rule, the most that can be done in the 

 way of retouching a lantern slide is the re- 

 moval of transparent spots by filling with 

 color. Knife work or any process that dis- 

 turbs the surface of the film, is inadmissible, 

 as, unless most skillfully done, it shows un- 

 pleasantly on the screen. It is possible, in 

 certain cases, to rub down dense portions 

 with methylated spirit, in the same manner 

 as is usual with negatives, but the instances 

 when such a procedure becomes necessary 

 do not often occur, and are principally those 

 in which it is desired to make the best 

 of a slide from a poor negative. 



Spotting should be done by the aid of a 

 fine camera, hair brush and color. The 

 precise color will depend on the color of the 

 slide, but India ink and Indian red will, 

 either singly or combined, match nearly all 

 slides. A reading glass of low power is of 

 great assistance in enabling the operator to 

 apply the color neatly to each spot. Fur- 

 thermore, no light should reach the lantern 

 slide from the back of the operator, or he 

 will fail to judge correctly the density of. 

 his spotting, and will .find when the slide is 

 shown on the screen that all the spotting 

 shows darker than the transparency. The 

 color should be kept of slightly less density 

 than the opacity of the slide, and to ensure 

 this, no light should reach the operator ex- 

 cept that which is transmitted through the 

 slide. . The color should be used in a viscid 

 condition, and tube colors are better than 

 dry, as the menstruum used in their prep- 

 aration gives them a good working consis- 

 tency. 



As a rule, lantern slides on commercial 

 gelatine plates are not varnished, nor does 

 there appear to be much necessity for var- 

 nishing them, as the film, unlike collodion 

 or collcdio-bromide, is not liable to be read- 

 ily damaged by friction. Varnishing intro- 

 duces the risk of applying specks of dirt and 

 hairs to the film along with the varnish. 

 On the other hand, if it is well done with 

 a clean, hard varnish, immunity is secured 

 from fungoid growths, which not infre- 

 quently make their appearance on gelatine 

 films, however well defended and carefully 

 stored. I always varnish a slide of excel- 

 lent quality, especially when it has caused 

 me considerable trouble to prepare. 



The following varnish has been spoken of 

 in high terms for varnishing lantern slides : 

 Saturated solution of amber in 



Chloroform 1^2 ounces 



Pure benzole i x /% ounces 



Gum dammar *4 ounce 



^When dissolved filter several times 

 through cotton wool. Warm the plate be- 

 fore varnishing, and dry well over a gentle 



heat afterward. It gives a hard, bright, 

 glassy surface. 



A convenient and reliable varnish is made 

 by dissolving one part of dammar in 20 

 parts of benzole. This may be applied with- 

 out heating the plate, and dries with a bril- 

 liant, hard surface. It is advisable in var- 

 nishing lantern slides to return the surplus 

 varnish from the plate to a second bottle 

 fitted with a filtering funnel and cotton 

 wool. By so doing a stock of well filtered 

 varnish is alwavs maintained. 



MIXING SOLUTIONS. 



Few amateurs who mix their own de- 

 veloper have any regular method for mak- 

 ing solutions. So much of this and so 

 much of that are weighed out, or sometimes 

 guessed at, and dumped into a bottle, the 

 cleanness of which is doubtful, and then the 

 required quantity of water is added directly 

 from the tap. Working in this careless 

 way it is no wonder that no 2 lots of de- 

 veloper give the same results, even when 

 mixed from the same samples of chemicals. 



In making a quantity of developer the 

 first point to attend to is the proper clean- 

 ing of the bottle. Traces of old developer 

 or any foreign matter cause rapid oxidation 

 of the fresh solution. A strong solution of 

 sal soda in hot water is good for cleaning 

 bottles, or failing that, strong soap suds ; 

 after which the bottle should be well rinsed 

 out in hot water. 



Use good, clean corks. A broken, porous 

 cork allows air to reach the solution and so 

 permits of rapid oxidation. 



It is easy to make trouble by carelessly 

 exchanging the corks of 2 bottles of differ- 

 ent solutions. If you misplace the cork of 

 your bottle of hypo solution, and later use 

 it to close your bottle of developer, there 

 will be trouble, and it may take you some 

 time to locate the cause. 



As regards the chemicals to be used, it is 

 hardly necessary to say that the best are 

 the cheapest. The ordinary commercial 

 grades of chemicals contain a variable per- 

 centage of foreign matters, some of which 

 are harmless from a photographic point of 

 view, while others are decidedly injurious 

 in their effect on the plate. Much of the 

 poor work turned out is directly traceable 

 to the use of cheap chemicals. 



Most of the textbooks on photography 

 advise the use of distilled water in mixing 

 solutions. This is hardly necessary for the 

 amateur, but I advise that the water used 

 for solutions be boiled. By this means a 

 good percentage of the impurities in the 

 water is removed and much of the air con- 

 tained in it is driven out. If developer 

 could be kept away from the oxidizing in- 

 fluence of the air, it would remain in good 

 condition almost indefinitely; so if most of 

 the air imprisoned in the water used for 



