120. Obtaining Proper Angle Of Light

Obtaining Proper Angle Of Light. This is thoroughly taken up in Paragraphs 74. Study the effect of light at different times of the day and when you find the time that projections and trimmings stand out in bold relief, make an exposure. If the building is high or low, watch the effects of the sun at various times of day. It is a good plan to study this at all times, even though you do not intend to photograph a building. It is a good practice and by so doing you are training your eye. In a short time you will have little trouble in selecting the proper time for making exposures and obtaining correct angles of light.

121. Obtaining. Straight Lines on Ground-glass. - If your camera is equipped with a swing-back, you can readily overcome this difficulty. First place your camera in proper position to take in the entire building, making use of the rising front to which the lens is attached. Next push out the swing-back at the bottom, providing it is a swing-back which is hinged or pivoted at the center. If the back swings from the bed of the camera, you must tip the back of the camera forward. In either case adjust the swing-back so that the vertical lines will come true with the lines of the ground-glass (focusing screen). If your camera is supplied only with a rising front, place the instrument perfectly level and then push up the rising front. If the building is very high, it is advisable to make the exposure from a second-story window on the opposite side of the street. This should always be done where one has neither rising front nor swing-back attachments as, for example, in a box or a hand camera. If there is no convenient building or raised ground on the opposite side of the street, you had better not attempt to photograph an extremely high building as the resulting picture will be bad. The building would be broad at the bottom and narrow at the top and in extreme cases would assume the shape of a pyramid.

122. Working In Close Quarters

Working In Close Quarters. When meeting this difficulty, which is generally caused by narrow streets, the only thing you can do is to use a wide-angled lens, but you must bear in mind that the perspective will suffer and it is advisable to make the image very small, because in a small image the false perspective will not show so strongly.

123. Obtaining Sharp Focus On Extreme Distance

Obtaining Sharp Focus On Extreme Distance. Always focus on the front of the building. Get this as sharp as possible without the use of a stop or diaphragm, and then stop down until the extreme distance is sharp. In such cases this is entirely governed by the cutting depth of the lens, but in most cases stop U. S. 32 or F. 22 will produce the desired results.

124. Image Very Thin And Hazy On Ground-Glass (Focusing Screen)

Image Very Thin And Hazy On Ground-Glass (Focusing Screen). If the camera is pointed toward the sun, the lens is affected as is the eye when looking directly into the sun. Everything appears hazy and dim. If the sun is to the extreme side of the camera, a sun ray may strike the edge of the lens tube and reflect directly into the lens, causing the above effect. In mid-winter if the camera is taken from a warm room into the cold, the change of the temperature will cause a moisture to gather on the lens and also on the ground-glass. All lenses, but more particularly those that are mounted closely, like the anastigmat variety, are extremely sensitive to the change of temperature. Moisture gathers very rapidly on them, and every time the moisture is allowed to dry it leaves a slight scum, a scum which is similar to that found on windows which have been steamed. This scum will in time affect the working of the lens, producing effects of both haziness and halation. Therefore, always carefully wipe with a soft cloth both lens and ground-glass before making an exposure. Occasionally take the lens apart and wipe the inside lens. You will often find it is necessary to use alcohol to thoroughly cleanse the lens.