8 mm projectors in the modern chemistry classroom - ACS Publications

technology of films, overhead projection, television, and classroom designs as they may apply to the aca- demic chemist and to developments for indivi...
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W. ROBERT BARNARD The Ohio State University Columbu.. Ohio

T h e field of ~ m mfilm production and preparation has made significant advances during the past year and has been the subject of considerable speculation. The enlarged interest of the academic chemist' in this field as well as the increasing number of puhlicat,ions and films in medicine, education,%and sales promotion holster claims that new concepts in S mm film presentations may offer improved teaching opportunities t,hrough the use of film in the classroom or laboratory. While it might be interesting to explore some of these, this column will limit its scope to the technology of films, overhead projection, television, and classroom designs as they may apply to the academic chemist and to developments for individual student instruction. 8mm Films

Presently, three of the four principal Smm gauge film formats are being used: the conventional Smm format, single4 and super-S. The M format is used only for printing (JIcGraw Hill); only one projector is available (Viewlex", and no camema are proposed for this format. The dimensional characteristics of single-S and super-S film gauges, as well as the image format, are identical (see Fig. 1). The 50% increase in image area of the super-S and single-S is made possible by changing the size and location of the film sprocket holes. The only difference in the two systems is the type of filmcamera cartridge used. Both gauges are interchangeable as far as projection is concerned. In fact, superS and Fuji's single4 can he joined with tape on the same reel if desired. Single9 has a polyester base on which acetate film cement will not work. The International Organization for Standarization has designated the term "Smm Type S" for both super4 and the single-S.

'Advisory Council a n College Chemistry, "Modern Teaching Aids for College Chemistry." ACa Newsletter KO.10, "Teaching Aids Programs." R., AND S L A ~ ~ U I !G .,H"Teacher-Prodoced , InstrueO'CONNER, tional Films i n Chemistw." .. Advisory Council on Collexe Chemistry. The Canadian National Film Board has scheduled for release a series of 15 loops a n the physics of motion. The Public Health Service hss proceeded with an extensive film program with 100 sound film titles. The list of 8 mm films published by Technicolor Corporation grew from 770 in 1964 to 4000 this year. a Viewlex, Inc., Broadway Avenue, Holbrook, N. Y. 11741.

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Journal of Chemical Educafian

8mm Proiectors in the Modern Chemistry Classroom

REGULAR8mm (14.3mm2)

SUPER 8 SINGLE 8 (21.5mm2)

16mm

( 69.5rnm2)

Figure 1. Comparison of regular-8, super-8, single-8, and 16mm film formats. The shaded oreas ore reserved for round.

A new concept in Smrn film has been introduced by the Panacolor Corporation for a new audio/visual unit. The Panacolor design puts twelve 8 mm wide images in adjacent horizontal rows on a 70 mm wide film, and each film row has a corresponding photographic sound track. Any subject with a 10-minute running time can be selected for random or successive projection in the film cartridge (see Fig. 2). Projectors

Super-S will undoubtedly become the format finding the greatest acceptance for educational and commercial Smrn film production. The switch to this format is virtually complete where cameras are concerned, since only one couot~y(U.S.S.R.) still has standard-8 equipment in current production. There is a trend towards production of dual-gauge reel loading projectors, both super and standard-8. These seem the logical choice for anyone who already uses standard-S film hut who may change to t,henew gauge some day. Adapting a dual-gauge machine from one format to the other consists of switching gates and sprockets (if any). Some models have loose parts which must be actually removed, while others have built-in changeover devices. In choosing a machine, one should note the general ease of the changeover and its general efficiency. Apparently, manufacturers are looking upon sprockets as unnecessary, especially for the popular priced American equipment. There is a wide selection of sprocketless machines available, and one advantage offered is that they have no film-loops to lose during projection. Most sprocketless projectors have a maximum capacity of 200 ft. Some machines offer slow-motion operation, and

Light Oufput Theoutstanding trend in 8mm projector design is toward more light on the screen. Projection lenses with f/1.3 openings are quite common. Several manufacturers have projectors with fixed focal length lenses of f/1.0, which theoretically would pass almost twice as much light as the f/l.3. Flaws in lens design, or in the light condensing system are apparent with these "fast" lenses and unless a purchaser is willing to pay a surcharge, the selection oi a projector with s n advertised highlight output based solely on the speed of the lens may not give total satisiaction. As an example: Eumig recently announced an f/l.0 zoom lens for their Mark D L series oroieetor. s. camhination which would he an e x a m ~ l eof a p x l qu.Arv hgl, ligllt 01111)111 lens with ~ppcoprii)teI q h t y t e r n . The prim. it.crr.i.-r I- ijc; vrr n sirnilnr s y m m a n h a Txvcl Irn;. ~ l u n ~ t e ~ . - lld td, s~ in~ J~i h~ o~w~ ~ ~ I I w I c h, m ~ e it.crea,+d light output in the newest projectors. Dichroic lamps came in two d e s i g n ~ w i t hseparable mirror (European) and with integral mirror (American). Lamp wattage is not necessarily agood guide to screen brightness, even rr.hen considered in relation to the lens opening or bulb type. For example, theEuropean 12 v 100wlamp achieves about the same screen brightness as the American 21" 150w. (The more compact filament of the lower voltage lamp achieves greater optical efficiency.) Since uniform measurements of projector light output in lumens are not generally available a t the point of purchase, the best way to evaluate hrighhess and overall picture quality is to put a machine in the classroom or laboratory and project the size image that is desired. Screen brightness is not the only aspect to judge, however; sherpners of focus and even illuminstion out to theedge of the projected image, flutter, and weave are other factors. It, does not follow that by paying more you will necessarily get greater screen brightness or quality.

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Lenses Zoom lenses, or more properly-variable-focus lenses, are now very popular. This is true even though the average zoom lens is bv no means o ~ t i c d has ' mod a. oerfarmer as a. non-zoom lens of Figure 2. la1 Zeirr Ikon's Panacolor mogazine projector uses o modifled 8mm format to store up to 2 hr projection on a single cartridge. Remote control enabler teacher to reverse, focus, select segments, ond control still projection%. This is the only projector "ring o rotating p r i m rather than a fllm gate; this feature ollowr greater light output on still projection. (bl Twelve rowr of picture and twelve rowr of optical sound ore ~ r i n l e don the Panacolor 70mm film.

many will project still pictures (which usually do not project well in the classroom), the film being protected by a heat filter which reduces the brightness appreciably. Some machines include a special fastrunning speed (2-3 times normal) useful for running a film ahead to find a "wanted" spot, or for running off the rest of n reel without bothering to unthread the machine.

weigh the quality factor. If a high quality soom lens is too expensive, then the fised lens focal length is the factor to consider when choosing a projector. As a guide, a 20 mm lens (about an average on many projectors) needs a projection distance of 4'/a times the screen width on standard-8 or 3a/4 times the screen width on super-8. I n general a student should sit no further than 6 tlmes the projected image width or closer than 2 times the width (see Table 1).

Table 1.

Factors Relating Focal Length of Lens with Screen Size and Proiection Distance

-Standard Focal length of projection lens

8mm---

Factor

----Super Focal length of pra'ection ?ens

&---

Factor

Threading Almost all projectors incorporate automatic threading systems. Usually these include the take-up spool, so the whole machine l i t e r a h t,hreads itself. No automatic threader is 100 nereent iug theloadingoperation; in the case of auto-load reel typeprojectors,an operator can manually assist anydamaged film through the projector. In ihe case of damage to film in a cartridge (genwally occnrring nt thespliees), the cartridgemust go hack to thesupplier for repnit.. The exception is a Fairchild projector cartridge which can be disassembled with a screwdriver. There are a t least 6 different film cartridges for standard-8 or super4 mm filmr. None of the cartridges are interchangeable among different models of projectors. The teacher selecting a cartridge loading projector will have to commit himself to that line of hardware and projection system. There is no hope in the immediate f ~ l t u r eof a "standard" cartridge which could be interchanged among all models of projectors in the same manner a. film reels are presently traded.

T o h d projection dlstnnee, multiply screen width by the appropriate factor. To find screen w ~ d i hdivide ihe factor into the projection distance. From the information currently available to us, illumination from the highest output projectors is sufficient to produce a. quslity 4 i t wide picture :n the average classroom.

Sound T h e problems in combining Smm film with sound have always included the physical limitations of placing a magnetic stripe or optical track, as well as providing satisfactory sound performance.

Volume 45, Number 2, February 1968

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137

Figure 4. The MPO Videotronic proiector features: super-8 film, cortridge loading, magnetic round, 10 X 13 in. self-contained screen. Proiector converts to conventianolfront screen proiection. Figure 3. The lowest priced sound super-8 proiector on the morket is the Kodak Ektogrophic sound-8. Ploys back magnetic sound only lcopocity: 400 ft.of super-8 fllml.

llecent developments in magnetically prestriped 8mm film stuck. (see Fie. 3 ) as wellas new nhotoeraohiesound receotor cells

gmges. For the teacher who wants to put his own narration on 8mm film, the basio tool is a magnetic stripe projector. These have heen specially designed far recording/playback and give superior neifurmance to silent nroiectors which have been fitted with mae" net,ic attachments. With a projector equipped for recording and playback oi magneticsound you need only amicrophone t,o record or add over an existing sonnd track. The quality of the sound reproduction from a magnetic stripe vavier wit,h t,he film gauge and the film speed: the wider the &pe and Lhe fsst,er the film speed, the higher the quality of the ~. ~.

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.3"11i,d.

The sound quality obtained with the latest Rmm magnetic sotllid project,ors nunning a t 18 frames per second is perfectly ade-

qust,e for mttine classroom use, although a speed of 24 fps is considered the standard for sound-film projection. Completion of mass-prod~tctionplans for processing super-8 prints may provide a clearer picture of the future for 8mm sound. At present, Xmm magnetic sound is the most flexihle and has the highest repmduction quality; it is also the most expensive, mtd Lhere have been dehys at the processors' in having stripes added to the processed film. The o,,lv ontical sound. cat.tridee load ssrmer-8 ~ r a i e c t a now r on

the s o m d on R separate magnetic tape and have the mund printed from the tape onto an optical printing track by the film pl.oeessor. Since there are established standards for identifying the start of a sound track ior printing purposes, and other conventions to fneililate handliug oi original film with separate narrat,ion on magnebic tape, consult s. film processor and ask for specific informntion on laboratory procedures.

Future Prospects

What does the future hold? Probably time has the teaching community had a portunity to influence the manufacturers hardware. The choice of film gauge, projection screen parameters, and sound rests with you the teacher. 138

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Journol of Chemical Edumfion

at no other greater opof teaching capabilities

In addition to high quality auto-loading 16mm sound projectors, you have been presented with Smm automatic loading projectors suited for individual or group instruction. Projectors are designed now with integral screens as well as lenses for regular front projection (see Fig. 4). Loading is as simple as putting a coin in the pop machine. T h e new Smm formats provide increased picture brightness and resolution. What are your demands? The most important point to remember is that there must not be a retardation of the flow of equipment from the manufacturers. Other items which will be presented to you soon may include a spool adaptor which will accept a standard spool of super-8 film and will provide a different, more convenient, mode of film storageand handling. Shortly, a projector will he available which allows automatic fast rewinding back into the reel adaptor. Such a projector would open up a new educational concept: almost instantaneous selection of teaching material within a reel of film. Perhaps the only item missing is a projector for large class presentations. We need a super-S projector capable of showing a picture in a classroom accommodating more than 50 students. Announced at the spring meeting of the Society of Motion Picture and Television Engineers mas a program of six European manufacturers of motion picture equipment for the development of a new single reel cartridge which would allow fast forvard and re-wind modes. The "EP" cartridge (for easy projection) would further simplify projector threading, adjustments for sound, film rewinding, etc. Already at the prototype state is the Iiodak 1l.F.S. Super-8 projector. I t projects moving or still pictures according to cue marks placed on the edge of the film. It can be used with a computer-controlled instructional system. A student can stop and reverse the film, as well as repeat or skip over sections. f Another innovation announced by Columbia Broadcasting and CIBA, a Swiss concern, would turn conventional TV sets into cartridge-loading projectors.

Table 2.

Directory of Representotive 8mm Motion Picture Projectors Pmiection speeds frame8

Maoofacturer Allied Impex Corm 300 Park Ave. S. New York. N. Y.

.""."

Model name T3

per

Lamp 87 50 v

Sound Silent

second (fps)

Lenses

+

9-18 still 18-30 mm frame 1 . 3 room

Threading

Film tmnsport

Film

Auto

Sprooket

Super-8

4 0 0 f t reel

Semiauto

Sprocket

Super-8

400 f t reel

gauge

Playing time"

Remarks

.fin,,,

(Rsuerl

T1S

12 v 100 w

T2 Bell and Howell 7100 MoCormiok Rd. Chicseo, Ill. 60646

DuKhne Corp. St. Charles. Ill. 60174 Paillard Ino. 1900 Lower Rd. Linden, N. H. 07036 (Bole4

Autoload 346

110 v 150 w

Autoload 466 Autoload 483-2

110 v 250 w 24 v 200 rv

28A8

"

Sm-8

12 v 100 w Halogen

18-5

8v 50 s

Eumia (U.S.A.) Inc. Mhrk S 101 W e a t 31st St. New York, N. Y. 10001

Fairchild Camera and Instrument Industrial Products Dir. 221 Fairchild Ale. plain vier^, N. Y. 11803

Mark Mark Mark Mark

M S DL IV

12 v 100 w

8v 50 w

Silent with external audio niser Magnetio

18-24

18-30 mm

Silent

18

25 m m 1.6

Variable

19-32 mm Auto 1/1.2,~00m Auto

OpticalMagnetic Mspnetio

1 - .4 ..rnnm ....-

18-24

28 mn 1l1.4 Semiauto

18 or 24

14-25 mm Auto zoom or 15. 20. 25 N1.3 fired ,, 15, 20. 2.5. fired l / l . 3 or 12.S25 zoom 18-28 m m Auto N1.0 room or 25 mm l/liO fixed ,,

Silent

18

Magnetic

18 or 24

Silent Mametic Silent Magnetic

Sprooketless Dual 8 / super-8 Super-8

Sprocket

24

7 . 5 mm 1/1.4

'

3 position hrieht"as switch

Su~er-8

6W f t

Sprooket

Super-8

400 f t reel

Sprocket

Regular 8

600 f t

"

' Sprocket. Magnetic Sprooket pak, eartridge for 8 or super-8

Supe:;8 8 or super-8 " Regular 8 Movie P s k Built-in 10 12 mi" aL/3 X 11 in. rear for reeu1nr 8. 10 screen. min for nkpnetio super-8 recording attar,>-

Mhrk I P S Jayark Instrnment 2 MS Cow 10 E. 49th St. New York, N. Y. 10017

~orooket

Super-8 super-8

Mhgnetlo

24

7.5 mm 1/1.4

~srtridge

Silent

18

28 mm 1l1.5

Magnetic

18 or 24

25 mm N1.5

Automatic Sprocketless 8 or reel to Super8 reel SemiautoSuper-8 matic threads UP to take up

8-54 still 2 S 3 2 1 5 Automatic frame room 22 reel to reel frame or 28 1/1.0 filed 24 20 or 25mm Cartridge Sprocket Il1.5

meat svailahie

Movie Pak 20 22 min rep.!"&' 8 30 min

,, Ruilein 4 x 12 in. rear screen. auto stoy, cued, to sensing

taoe Eastman Kodak Co. M-65 125 v 343 State St. 150 w Roehestcr. N. 1.14650 Ektagra~llic " solmdd

M.P.O. Videotronios. 1ne.

528 N. Miohichn Ave. Chioapo, Ill. 60611

M-95

21 V 150 w Halogen

Silent

Videotronia super-8

21.5 v 150 w

Magnetic

200 i t

me,

+

8 or anper-8 400 f t

See o w tion, Fig. 3

Super-8

Built in 10 131/P in. real Screen also front

x

ween

Magapine projector

12 v 100 w

0pti0e.l

24

For fcont

Automatic Sprocketless 12 8 mm 12 topics p y e ~ t i o n reel to reel pictures 10 min wrll fill I" s magaon 70 m m each 40-in. eme film meen at 30 f t ~

Film o m h e reversed. Builtin8 x 11 in. mar

mreen. also frbnt

~

sereen

830

840

12 ri 100 w

Silent

Synchronized wterne.1 tape recorder

8-26

19-30 1/1.6 room or 25 m m 1/1.3

Automatic Sprooket reel t o reel

Super-8

400 f t

proieotion. Has remote oontroi Built in editins device Cou~les a">-

standard 31/, ips recorder to proieetor for ~ynclllo"ired sound

Volume 45, Number 2, February 1968

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Table 2.

Continued

Projection epeedl

Manufacturer Technioolor Corp. P.O. Box 517 1300 Frawley Dr. Costa Mew, Calif. 92627

frames Per

Model name 510

Sound

Lamp

150 w incandes cent

Silent

seoond

Lensea

(fpd

20-32 mm //1.4 or 10 mm

18

Threading Cartridge

Film transport

gauge

Film

Playing t,mea=

Super-8

4 mio.

Remarks

//l.l

Inoluden sriil picture clutch

810

and

1000

21.5 v

150 w hklogen

:Running t i m e d m o t ~ o npicture Elm:

200ft.

rrsnsfor mer for inoreased hght output Optical

20 mm

24

super-sat 18fpa. 14 min;

//l.l

200ft a u p e i d a t 24 fps. 9 mio.

The EVR (Electronic Video Recording and Reproduction cartridges) are capable of carrying up to one hour of black and white or half an hour of color programming. The cartridge is inserted into a player-presumably something like a tape recorder-and attached to the aerial terminals of the TV receiver. The film is played by means of what the manufacturers call an optical converter unit, and is reproduced on the TV screen. The player threads the film automatically to the take-up reel, and after playing, the cartridge rewinds and is automatically ejected. The EVR player

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journal of Chemical Fducofion

30 min.

is not a videotape unit, and the film it plays will be made only in the processing plants specially designed for the purpose. The film in the cartridge is 8.75 mm wide, on a special, thin base, unperforated, and can he stopped for single frame display. So the same EVR machine could take over the job of both the movie projector and filmstripe projector or micro film reader. The first full-scale applications mill be made in England next spring. The future for small gauge film and the teacher could not be brighter!