Kodak reports to laboratories on:Ektar lenses for 70mm cameras ... setting the valves in a chemical plant...a new idea in photographic emulsion making

The new lensesIt is conceivable that these threelenses are going to usher in a newphase in camera design. Whetherthey will or not depends on theeagerness with which designers at-tack the problem of 70mm film.

Kodak Ektar Lens, 21/2-inch ff4.5back focal length ............ 52.63 mmlength ..................... 23.00 mmfield to corners of 70mm frame..... 700distortion 23.10 from axis..... +.065 mmdistortion 33.50 from axis..... +.254 mm

Kodak Ektar Lens, 4-inch ff2.8back focal length ....... ..... 73.81 mmlength ..................... 41.69 mmfield to corners of 70mm frame .... 480distortion. 180 from axis....... +.18 mmdistortion 22°from axis....... +.28 mm

Kodak Ektar Lens, 8-inch ff4back focal length............153.98 mmlength ..................... 77.15 mmfield to corners of 70mm frame...... 240distortion 7.50 from axis......+.035 mmdistortion 12°from axis.......+.144 mm

Image quality of these lenses isgood, very good indeed-so extraor-dinarily good that the 70mm nega-tives are probably fairly close forover-all detail content to big nega-tives made by many an acceptablelens of considerably longer focallength. Rarely has a designer sofreely been given his head, and rarelyhas one tried so hard and succeededso well in working out a series oflenses with the sharpest imagery forone fixed picture area.

Since we are also a manufacturerof film, you might think that wewouldn't have wanted him to try sohard to make 70mm film do thework of wider film. However, wedecided long ago that that kind ofthinking was no way to get ahead

in the business world.Sorry, we're not in a position to sell

you one ofthese lenses. We are preparedto enter into negotiations for the manu-facture of quantities of them to individ-ual mounting specifications. Address in-quiries to Eastman Kodak Company,Special Products Sales Division, Roch-ester 4, N. Y. Have you ever thought ofus as a contract shop for optics ?

Isobutyraldehyde

A chemical plant is a fancy plumb-ing job animated by an idea. Wehave one at Longview, Texas, ani-mated by this idea:CH3CH= CH2+CO+H2.-3CH3CH2CH2CHO+(CH3)2CHCHO

In words, natural gas, refinery by-product propane, and steam areturned into butyraldehyde, normalor iso. (This is known as the OxoProcess.)

Right now the valves are set fora certain ratio of normal to iso.We have a very strong and ever-growing internal demand for com-pounds that start from n-butyralde-hyde. The isobutyraldehyde, per-haps reduced to isobutyl alcohol oroxidized to isobutyric acid, leavesour hands at an earlier stage in itscareer. The iso aldehyde, alcohol,and acid are all points of departurefor a great variety of interesting re-actions. Most of these are of moreindustrial importance to other com-panies than to us. We should like tomake certain that all of their voiceshave been heard before decidingthat our setting of the valves is eco-nomically correct.One of the principal ways the

chemical industry grows is through

the posing of questions like this. Areaction becomes practical that wasimpractical before because one ofthe reactants is more abundant thanit had been. Somebody is likely tomake money as a result. The key iscommunication.

Ifyou can see enough connection withyour problems to sendfor a free copy of"The Chemistry of Isobutyraldehydeand Its Derivatives," the first stone in alandslide of events may be rolling now.Write Eastman Chemical Products, Inc.,Chemicals Division, Kingsport, Tenn.(Subsidiary of Eastman Kodak Com-pany).

Royal PanOnce in a while the orderly flow ofprogress in photographic technol-ogy makes a gush, and then youhave something as important as abasic advance in emulsion making.It's fairly rare.What has happened is that at

long last we have found somestretch in the chains that lock graini-ness and light sensitivity in mutualbondage. We can make an emulsionthat gives less graininess withoutyielding sensitivity, or we can havesensitivity without paying in graini-ness. The latter seemed the betterchoice for the first commercial ap-plication, which we call Kodak.Royal Pan Film.

Its graininess is perhaps even alittle less than that of the highlysatisfactory Kodak Super Panchro-Press Film, Type B (fastest Kodakfilm hitherto offered the press pho-tographer, a connoisseur of emul-sion speed), but at the practicalgamma of 0.7 it has twice the speed.Exposure Index is 200 for d4ylight,160 for tungsten. Its characteristiccurve combines the best features ofKodak Super-XX PanchromaticSheet Film and Kodak Super Pan-chro-Press Film, Type B. There ismore exposure latitude, more de-velopment latitude, more detail inthe dark areas, more detail in thelight areas, less need for dodgingin printing.

If your work, business, or hobby hasbeen crying out for faster sheet film, allyou need do now is send someone out tothe nearest Kodak dealer for someKodak Royal Pan Film. There mightbe several press photographers atthe counter ahead ofhim. A

This is one of a series of reports on the many productsand services with which the Eastman Kodak Company andits divisions are ... serving laboratories everywhere

UNIVERSITY PRESS

Dynamics ofGrowth Processes

Edited byEDGAR J. BOELL

Fourteen outstanding leaders in research onvarious aspects of growth present a concertedattack on the problem of growth dynamics in asymposium sponsored by the Society for theStudy of Development and Growth. Contribu-tors: Gordon E. Dickerson, G. Fankhauser,Robert Gaunt, W. W. Greulich, Lloyd M. Koz-loff, Aaron Novick, Arthur W. Pollister, KeithR. Porter, D. A. Sholl, Folke Skoog, FrederickE. Smith, Leo Szilard, D. S. Van Fleet, F. W.Went. 312 pages. Plates and diagrams. $7.50

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TmE RICKETTSIALDISEASES OF MAN

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