Amateur Photographer & Cinematographer (1934)

The AMATEUR PHOTOGRAPHER p 6 CINEMATOGRAPHER a February 7th, 1934 the source on to the subject, or as it comes from the subject itself towards the camera. The “ life ” of the meters appears to be more or less permanent, provided they have the same usual care as is given to the camera itself. Their sensitivity curve is not very dis¬ similar from that of photographic emulsion, and they give a fixed amount of current, and so a definite reading, for a given illumination, and this is repeatable. Their value varies only slightly in extremely low temperature (freezing point), but it does alter at high temperature, and, in any case, if used for tropical work, the meters would probably have to be re-calibrated. They cannot be used to measure the factors of filters commonly used with the panchromatic plate, except for the instance of the Weston in respect of infra-red just mentioned, but Dr. Harrison thought they would be of assistance in screen-plate colour work, and that they could be used for calculating the relative value of the factors for three-colour separation negatives in different ilium inants. It remains to add that the meters for their size appear rather costly. It was mentioned by a speaker in the discussion that one instrument of this kind, the Photo¬ lux, costs 29 marks in its country of origin ; the Metraphot costs £3 7s. ; and the Ombrux £4 4s., while there is a French type which costs £ 8 5s., but this is graded in both micro-amperes and light units so as to give a direct reading of the actual light instead of a rather arbitrary scheme of gradation ac¬ cording to some plate speed. Tut, Tut ! “ These,” said the demonstrator of some new apparatus last week, “ are designed for the amateur user, and in those which we design for the professional man — by which I mean the man who really knows what he is doing — other devices will be incorporated.” The idea of the amateur implied in that remark, we thought, had longsincebeenexploded. The A mateur Photographer” EXPOSURE TABLE — February EVERY MONTH a brief exposure table will be provided for the assistance of our readers in their practical work. A glance at the current approximate exposures as here given will serve as a reliable guide for most purposes. The subjects will be varied to suit the time of year. The following exposures will serve as a working guide for any fine day during the month, between the hours of 11 in the morning and 1 in the afternoon, with the sun shining, but not necessarily on the subject. Stop used, f/8. The exposuie should be doubled if the sun is obscured, or if stop f/11 is used. For f/16 give four times the exposure. For f/5.6 give half. From 9 to 11 a.m. or from 1 to 3 p.m., double these exposures. From 8 to 9 a.m. or from 3 to 4 p.m., treble them. Subject. Ordinary Plate. Medium Plate. Rapid Plate. Extra Rapid Plate. Ultra Rapid Plate. Open seascapes and cloud studies . . 1/20 sec. 1/30 sec. 1/60 sec. 1/80 sec. 1/100 sec. Open landscapes with no very heavy shadows in foreground, shipping studies or seascapes with rocks, beach scenes, snow scenes with no heavy foreground . . 1/10 y y 1/15 y y 1/30 y y 1/40 y y 1/50 y y Ordinary landscapes and landscapes with snow, open river scenery, figure studies in the open, light buildings, wet street scenes 1/4 y y 1/6 y y 1/12 y y 1/15 y y 1/20 y y Landscapes in fog or mist, or with strong foreground, well-lighted street scenes . . 1/3 y y 1/4 y y 1/10 y y 1/12 y y 1/15 y y Buildings or trees occupying greater portion of picture 3/4 y y 1/2 y y 1/4 y y 1/5 y y 1/6 y y Portraits or groups taken out of doors, not too much shut in by buildings . . 2 secs. 4 y y 3/4 y y 1/2 y y 1/3 y y Portraits in well-lighted room, light sur¬ roundings, big window, white reflector . . 6 y 1 4 secs. 2 secs. 4 y y 1 y y As a further guide we append a list of some of the best known makes of plates and films on the tnarket. They have been divided into groups , which approximately indicate the speeds referred to above. The hypersensitive panchromatic plates and films require less exposure than the ultra-rapid. Ultra Rapid. Agfa, Special Portrait. „ Super Pan. Film. „ Super-speed Film. „ Isochrom Film. „ Ultra Special. Barnet, Press and Super Press. ,, XL Super-speed Ortho. „ Soft Panchromatic. „ Studio Fast. „ Ultra Rapid. Criterion, Enelite. Eastman, Par Speed Cut Film. „ S.S. Cut Film. „ S.S. Pan. Film. Gevaert, Super Sensima. ,, Sensima Fast. „ Sensima Ortho. ,, Super Chromosa. ,, Roll Films and Packs. Haufp, Ultra Rapid. „ Ulcroma. „ Ultra Roll Film and Pack. Herzog, OrthoIsodux Film Pack. Ilford, Golden Iso-Zenith. ,, Iso Zenith. „ Hypersensitive Pan. Plates and Films. „ Portrait Film (Ortho Fast). „ Monarch. „ Press. ,, S.S. Ex. Sens. ,, Zenith Ex. Sens. ,, S.G. Pan. Illingworth, Fleet. „ Super Fleet. „ Super Fleet Ortho. „ Pan. Fleet. Imperial, S.S.S. Press Ortho. „ Eclipse. „ Eclipse Ortho Soft. „ Eclipse Soft. „ Eclipse Ortho. ,, Eclipse Pan. Soft. Kodak, Verichrome Film. Marion, Record. ,, Iso Record. Selo, Selochrome Roll Film and Film Pack. „ Selo. Pan. Roll Film. Standard, Film. Wellington, Anti-screen. „ X Press. Zeiss Ikon, Pemox Roll Film and Packs. Extra Rapid. Agfa, Chromo. „ „ Isolar. „ Extra Rapid. „ Isolar. ,, Iso Rapid. „ ,, ,, Chromo. „ Roll Film. Barnet, S.R. Pan. ,, Studio Ortho. Criterion, Iso E.R. ,, Portrait. „ Roll Film. „ Special E.R. Ensign, Roll Film. Gevaert, Filtered Ortho. ,, Chromosa. „ S.R. „ Regular Cut Film. Haufp, Analo-Flavin. „ Extra Rapid. „ E.R. Ortho. „ Roll Film and Pack. Ilford, Auto. Filter. „ S.R. Pan. „ Pan. Film. „ Rapid Chromatic. Imperial, Non-filter (new series). ,, Eclipse Pan. B. ,, S.S. Ortho. Kodak, Roll Film and Film Pack. Pathe, Roll Film. Selo, Roll Film. Zeiss Ikon, Roll Film and Film Pack. Rapid. Barnet, S.R. „ Self-screen Ortho. Criterion, Extra Rapid. Hauff, Ortho Anti-Halo. Ilford, Screened Chromatic. „ S.R. ,, Commercial Ortho Film. Imperial, Non-Filter. „ S.R. „ S.R. Ortho. Kodak, Cut Film. Lumiere, Extra Rapide. ,, Instantanfe. „ Pelliculaire. Medium. Ilford, Empress. ,, Chromatic. Ordinary. Barnet, Ordinary. Criterion, Ordinary. „ Ordinary Iso. Gevaert, Ordinary. Ilford, Ordinary. ,, Rapid Process Pan. Imperial, Ordinary. ,, Pan. Process. 6 120