American cinematographer (Jan-Dec 1941)

HERE S HOW Glass vs. Gelatin Filters What are the respective merits of glass-mounted filters as compared to gelatin filters (unmounted)? Would you advise me to have a filter-slot cut in my camera so I can use gelatin filters? Patrick Smoielloff. Probably the chief advantage of using a glass or glass-mounted filter in front of the lens is that it is a bit more convenient, and of course the glass mount of the filter gives the gelatin filtering material some physical protection. On the other hand, the glass filters are more expensive — quite a consideration if you are using filters of types which may not be stable, and have to be replaced frequently — and if you are doing completely professional camerawork, where optical quality and definition must measure up to the highest standards, it is not particularly desirable to have to shoot through any more pieces of glass than you absolutely have to. Many studio cinematographers prefer to use gelatin filters for these reasons: by using the gelatin filter you eliminate two glass-air surfaces which cut down definition and absorb light; and since a gelatin filter mounted in a filter-slot directly in front of the film permits using a much smaller filter, and since gelatin filters are much cheaper than glass-mounted ones, the expense is rather considerably reduced, so that it is quite practical to use a new filter on every production, or whenever the filter you have been using begins to fade or show signs of handling. For strictly professional use, gelatin filters in a proper mount and a wellmade filter-slot would probably be preferable. But for most amateur use, the glass-mounted type are much more convenient, and quite satisfactory for most purposes. Operatic Scenes With a 1-inch f .1.8 lens and Super-XX film do you think I can get satisfactory pictures of (a) an operatic scene and singers on a stage that is normally lighted, and (b) the audience applauding, etc., taken from backstage. These scenes would later be worked in together with other scenes taken backstage where I can control the light. W. M. Sheridan. The term "normally lighted" as regards a theatrical or operatic stage covers quite a range of lighting, depending on the theatre, the methods and equipment of the individual opera company, etc., but we're inclined to think you could probably do it. Nearly twenty years ago, with ortho film that hadn't nearly the Mazda-light sensitivity of today's super-panchromatics, we made fair stills of such action with an /:4.5 lens at % second, and when the Leica first took hold, we saw quite a lot of stage stills made on the early super-sensitive film at /:2 at l/l()th, so with today's film and equipment you should be able to do it. Since you won't be in a position to take an accurate meter-reading, though, we'd suggest if at all possible you should make a test at an earlier performance. If this doesn't give you as full exposure as you want, go ahead and shoot, and then before having the film processed, give it mercury-vapor hypersensitization. Place the film, on the camera-spool but not in its can, in a light-tight box, and in the same box, but below the film and placed so no direct contact will be possible, place a small amount of mercury in a dish. Seal the box so it is both light-tight and airtight, and leave film and mercury there for from eight days to two weeks. Then remove the film and have it processed immediately. President John B. Smurr of the San Francisco Cinema Club reports using this method successfully even for Kodachrome, with which he filmed the "Ice Follies" very successfully in color. Prescored Songs Recently in this column you told us how music is prescored and the actors later "mouth" the words in making various types of shots. Cannot long-shots where the singers' actions are not clearly discernible be taken first as in the question above, and then fitted with music which is later recorded? Can "mouthing" the music be done so successfully in close-ups that the faking is not discernible? It seems that in practically all the close-up singing I have seen on the screen the recording has been direct, since there appears to be no trace of faking. W. M. Sheridan. The method of post-recording you outline can certainly be done, especially if you have some means of synchronizing your projector and recorder, as by driving both with synchronous motors, or using Synchro-Sound synchronized disc recording equipment. It is sometimes done professionally; we can recall, in fact, at least one major picture of recent years in which the actor playing a prominent part did not have the type of speech and accent to suit the part, so when the picture was edited, another player, with the desired accent "dubbed in" every bit of that player's dialog by this method. Photographing singing close-ups to a prescored sound-track very definitely can be done so successfully that no "faking" is evident. As a matter of fact, the majority of the scenes of that nature you have seen and accepted as direct recording have been prescored that way, even to the close-ups! We can only think of one or two screen singers who do //of work that way — and those players are not particularly active at present, so we can say about 9% out of 10 singing close-ups today are prescored. Professionally, the task is made much easier by the fact that the original recording, either on film or an acetate disc, is played back at the time the picture is made, with the playback electrically synchronized with the camera. Thus the actor has only to follow his own voice as it comes through the loudspeaker on the set, and make the necessary movements and expressions. Usually he, or she, sings audibly at the same time, and this is also picked up by a microphone and recorded separately, so that the filmeditor has a very positive guide to getting the picture and the original soundtrack synchronized. Viewing Filters I am planning to purchase a viewing filter, and would like an article on the why and how of these filters before doing so. I use only pan film both indoors and out. C. Polychronis. The "monotone filter" or viewing glass serves several useful purposes. Looking at a scene through one of these filters, you can view it more as the camera and film will see it, rather than as your eye does: the filter reduces things to a monotone, and shows the colors, not as they will appear to the eye, but in pretty closely the relative tones and gradations in which the film will reproduce them in black-and-white. On an exterior scene, you will find that after a little practice, you can usually superimpose your viewing-glass and any given filter (except the nearly opaque Infra-Red filters like the Wratten 88) and form a very fair estimate of what that filter is going to do to the color rendition of the scene, how it will correct the sky, etc. On interiors, the viewing-glass is also extremely helpful in checking up on lightbalance, showing the cinematographer about how his highlights, half-tones and shadows are balanced in relation to each other. Of course it tells nothing about exposure, but it does give an excellent guide to light-balancing and color rendition. Several firms make these filters, including Scheibe, Harrison and Harrison, Eastman (Wratten) and others. Some of the film manufacturers have put out, for professional use, viewing filters intended to be specifically a guide to certain of their products. Obviously, the viewing filter and the film used must be closely coordinated, or the conclusions you reach inspecting a scene through the viewing glass won't be accurate. We would suggest that you make sure in buying a filter of this type that it is really suited to the precise type of film you are using. For example, a viewing glass designed for use with Agfa's Triple-S Pan, which is quite highly redsensitive, would be very misleading if used for DuPont Type 1 Superior, which has a much lower red sensitivity, and a good deal higher green sensitivity, and a filter intended for use with either of these films would be misleading if you tried to use it with, say, Eastman's Panatomic-X. Viewing filters have been made for use with Technicolor, and their is no reason why similar filters couldn't be made for use with the various Kodachrome film-types, as well. 584 December, 1941 American Cinematographer