The international photographer (Jan-Dec 1935)

June, 1935 The INTERNATIONAL PHOTOGRAPHER Eleven all the solutions at between 65-70 degrees F., and employing a rinse between the developer and fixing bath, this trouble can be avoided. Using the "Electric" Meter: Many photographers will acquire a photoelectric exposure meter this summer so as not to miss any opportunities during the coming vacation. Undoubtedly these meters are extremely accurate in their ability to measure the actinic value of the light, but they are mechanical contraptions and cannot think. The owner usually assumes that it is only necessary to point the meter at the scene or object to be photographed and it will indicate the correct exposure. In general the photoelectric meter covers a greater angle than that embraced by the usual photographic lens, so that the meter will take in a greater area in its reading than that which is to be photographed. Let us assume that the scene which we are photographing consists of a person in an open landscape, against a background which includes a large expanse of sky, and the exposure is to be such as to correctly reproduce the individual being photographed. When the meter is pointed at the latter it will include in its reading the large expanse of sky as well as the subject, and if the exposure indicated is given, the subject will be under-exposed. In such a case the proper procedure is either to go up close to the subject to take a reading, thereby cutting off much of the external influences affecting the meter, or to point the meter downward so as to include more foreground material and less of the bright sky. Similarly in taking close-ups of an object, it is best to approach to the latter and take a reading of the shadow side to arrive at an exposure which will reproduce detail in the latter. It must be borne in mind at all times that the fact that the photoelectric meter is extremely accurate is not sufficient to obtain the best results. Thought must be applied to its use. Photographers new to the use of this type of meter usually blame the meter for poor results, whereas their technique in its use is incorrect. iWhile we are on the topic of meters we might as well stress a point in connection with the use of the visual type of meter. The photographer must wait a few seconds after placing the meter to the eye and before taking the reading to allow the eye to become accustomed to the dark interior of the meter. Especially is this true in the summer when photographing in bright sunny outdoors. Unless the iris of the eye by changing the size of the pupil, is allowed to compensate for the change from the bright sunshine to the dark interior of the meter before the latter is manipulated, a wrong reading will be taken Although usually included in the instructions supplied with the meter, this point is overlooked many times. Prepared M. P. G. Developer: Last month formulas for metol, paraphenylene-diamine, glycin developer were given, but there are many in our miniature camera clan ■whose lack of sufficient time or space makes necessary the use of prepared developers. Such photographers need not feel at a loss in the matter of trying this new type of formula, for a prepared developer containing the above three developing agents can be obtained. It is known as M. P. G., and is claimed to produce clear brilliant negatives full of shadow detail. Full details of this prepared developer can be obtained from the R. J. Fitzsimons Co., 75 Fifth Avenue, New York City. Weak Prints: Metol-hydroquinone formulas are usually employed for paper developers, and if the solution is too cold (50 degrees F. or less) weak flat prints will be produced. The reason for this is that at 50 degrees F. hydroquinone ceases to act, so that the only developing agent affecting the paper is metol. The latter gives thin images full of detail whereas the hydroquinone gives density .The remedy is obviously to warm the developer to a temperature between 65 to 70 degrees F., BY AUGUSTUS WOLFMAN so that the hydroquinone could become active again. Temperature of the solution is important in the making of the prints, as well as in the preparation of negatives. Tips on Hot Weather Processing: Many photographers whose summer vacation covers a considerable time adopt the practice of developing their negatives while on the trip. Unusual hot weather conditions may be encountered, and there may be occasions when the temperature of the water obtainable for the preparation of solutions is relatively high. When the temperature is 75 degrees F. or above trouble may be encountered such as fog, reticulation, etc. In developing at temperatures from 75 to 85 degrees F. use any good developer but increase its strength so that it will develop the film in from three to four minutes at 85 degrees F. If development is carried beyond this point the film might become unduly swollen. Should a formula call for eight minutes development at 85 degrees F. double its strength and it will develop the film in four minutes. If the developer tends to give excessive fog at this temperature add a little potassium bromide. After development rinse the film for not more than two or three seconds in water, and immerse it in the following hardening solution: Potassium Chrome Alum 1 oz. Water, to make 1 quart The film is agitated when first placed in this solution and which is usually sufficient time to give maximum hardening, is kept immersed in the latter for not less than three minutes, Films which have been treated with a chrome alum hardener should always be wiped carefully after washing, and previous to drying, otherwise a chromium scum may dry on the film and leave a stain which cannot be removed. After leaving the hardening bath the film should be so hardened that the gelatin will not dissolve off in boiling water. It is now placed in the usual fixing bath until the unexposed emulsion has been dissolved away, and then washed. Above 85 degrees F. the development of miniature camera films is not recommended. Some workers prefer the use of formalin as a hardening agent, in which case the film is hardened prior to its being placed in the developer. A 10 per cent solution of formalin is used, which is prepared by diluting commercial formalin (40 per cent solution of formaldehyde) 1 to 10 with water. (Turn to Page 23) Announcing VARIABLE AREA Recording Equipment for the Producers who Do not have Laboratory Gamma Control ArtReeves j-[oiry^vood I^oTion PigTure/EpuipmenT(o. |Td. 645 NORTH MARTEL AVE CABLE ADDRESS ARTREEVES HOLLYWOOD, CALIFORNIA, US A Please mention The International Photographer when corresponding with advertisers.