PHOTOgraphic 1

Photography through themicroscope, or more commonly,photomicrography, has long beena useful tool for scientists.However, anyone who has accessto a simple light microscope canproduce highly color-saturatedphotographs, which display anexciting blend of art and science.Simple light microscopes withhigh-quality optics can be pur-chased for as little as $250, andadapters for most cameras areavailable for $25 to $75 (see the

accompanying list of microscopemanufacturers and distributors).Photographers who have access tostate and government-surplusfacilities may often find ratherexpensive surplus microscopesavailable at reasonable prices.Expensive high-powered micro-scope objectives (lenses) have avery narrow depth of field and arenot really useful; therefore, alower-cost 5x or 10x objective,which usually comes, as standardequipment on most microscopes,

is all that is needed. All of thephotomicrographs in this articlewere taken using a Nikon 4x or10x objective. You can addpolarizers to your microscope forjust a few dollars, and the use ofpolarized light allows you to getbeautiful photomicrographs ofcrystals made from commonhousehold chemicals.

GETTING STARTEDThe first polarizer is inserted atthe base of the substage con-denser (shown in the microscopediagram on page 5) and can beheld in place with tape. If themicroscope has a built-in lightsource, the polarizer can beplaced over the field lens. Thesecond polarizer, commonlytermed the analyzer, is placedinside the body of the microscopebetween the main-body tube andthe eyepiece tube. There isusually a lens mount at the top ofthe body tube, and the analyzercan be placed directly on thismount. You will need a polarizerthat is approximately 1-3cm indiameter because of the restrictedarea within the main body tube.This can be obtained by cutting apiece of polarized sheet plastic orbuying a small polarizer from ascience-supply distributor.

Next, rotate the polarizer untilthe viewfield becomes very dark.

Michael W. DavidsonNational High Magnetic Field Laboratory (NHMFL)

and Center for Materials Research and TechThe Florida State University

Tallahassee, USA

Fascinating Photos with a Simple Microscope

“Nebraska” is a triple exposure of recrystallized ascorbic acid (thewheatlike plants in the foreground) stretched polyethylene (the morningsky), and the field-diaphragm image defocused and photographed through ayellow filter (the yellow sun).

PHOTOgraphic 2

polarized light emitted from thepolarizer, and will bend it until itis visible through the analyzerwhen the polarizers are crossed.

To prepare crystals for exami-nation in the microscope, yousimply deposit a few granules ofthe crystal onto a microscope slideor a thin piece of 2 x 2-inch glass.Next, carefully place a microscopecover slip, easily obtained from ahobby shop or science-supplyshop, over the crystals and heatslowly with a match or cigarettelighter until the crystals meltcompletely (a bunsen burner or

At this point, the polarizationdirection is perpendicular betweenthe polarizer and the analyzer, andyou have what is termed crossedpolarizers. When purchasingpolarizers, remember to selectpolarizers that are very close to aneutral gray in color, such as thethreaded polarizers made for thefront of a camera lens. Avoidpolarizing materials that are greenor amber in color.

It is very important to ensurethat your microscope is aligned toproduce even illumination acrossthe viewfield. Information inmicroscope alignment is availablein owner’s manuals or in text-books dealing with microscopy.An exceptionally good book,Photography Through the Micro-scope, is available from Kodak(Publication P-2), and can bepurchased in many camera shops.

Most crystals are anisotropicand birefringment, which meansthat they will refract plane-

A single exposure of thiamine(vitamin B1) crystallized fromslowly evaporating solution inethyl alcohol produced this“bubbling” image.

transmit much light, and are not ascolorful as thinner preparations.If you don’t like the crystalformations after recrystallization,re-melt the sample and allow it torecrystallize a second time.

Another effective method ofpreparing crystals is to dissolvethe chemical in a suitable solvent,like water, rubbing alcohol, ormineral spirits. This method isespecially useful for chemicals inthe salt family, like table salt,Epsom salts, Alka-Seltzer, andbaking soda. Salts will usuallydecompose when heated, leaving atarlike mess. However, whendissolved in water or alcohol,these salts will slowly recrystal-lize as the solvent evaporates toform colorful crystalline patterns.Many chemicals can form differ-ent types of crystals, depending

alcohol lamp will do a very goodjob, if available). When melted,the crystals will flow underneaththe cover slip and fill the entirevolume between the cover slip andfill the entire volume between thecover slip and the microscopeslide. Allow the slide to cool, andplace it in a safe place for a fewdays to permit the melted chemicalto slowly recrystallize. Very thickcrystal samples will usually not

A single exposure of sulfurrecrystallized from the meltproduced this pattern. Thispattern is a single exposure of 3’-azido-thymidine (AZT) recrystal-lized from the melt. This drug iscurrently the most clinicallyeffective treatment forHIV-infected AIDS patients.

A single exposure of aspartamerecrystallized from the meltproduced these unusual forms.This amino-acid derivative hasbeen found to prossess greatsweetening power, and is theactive ingredient in Nutrasweet®.

PHOTOgraphic 3

on whether they are melt-recrys-tallized or recrystallized fromsolution. Some chemicals recrys-tallize almost immediately, whilesome take hours, days, or evenweeks. The chemicals listed in theaccompanying table are easilyobtained, and will recrystallize ina reasonable amount of time toyield beautiful photomicrographs.Several examples of photomicro-graphs of household chemicals areillustrated.

CHOICE OF FILMThe majority of microscopes use atungsten-halide bulb as a lightsource. These bulbs emit a verybright light with a wavelengthspectrum centered in the 3200 Kcolor-temperature range. Thereare a wide variety of films avail-able that reproduce this colorbalance correctly. Kodak’sEktachrome 50 and 160 are goodexamples of transparency filmsthat are tungsten-balanced;however, I prefer the good contrastand color saturation provided byFujichrome 64T. Photomicro-graphs are notoriously low incontrast, so I usually underexposeone or two f-stops and push E-6processing one f-stop. Thisincreases the contrast and color

saturation, without a significantloss in density. For Kodachromelovers, Kodak makes a fine-grained ISO 40-speed, 3400 K-balanced Kodachrome, which canbe corrected, for a tungsten-halide light source by the additionof a No. 82A filter between thelight source and the first polar-izer. If you are in a hurry,Polaroid’s High ContrastPolachrome HCP (ISO 40) will

produce very good results. Withany film, it’s wise to bracket thefirst roll to get a handle on exposuretimes.

CONSTUCTION OF“MICROSCAPES”By taking advantage of multiple-exposure photography, you canconstruct images that bear anuncanny resemblance to alienlandscapes. Several examples ofthese photomicrographs, which Icall microscapes, are included here.You will need a camera that allowsfor multiple exposures, and a vividimagination, to create these types ofphotomicrographs.

The first step in microscapeconstruction is to expose a fore-ground. This can be any number ofcrystals, although I commonly useascorbic acid (vitamin C) crystals,which in many cases resemblewheatlike plants or sea oats. Thefirst exposure is made on the film,and then a mask is placed on thefield lens (see the microscopediagram on page 5) to block anyadditional light from reaching thatportion of the film.

The next exposure is a mountain(made from, again, a number ofchemical crystal formations) or

“Mexico Beach, Florida” is four exposures on a single frame of film:recrystallized ascorbic acid (the sandy, rocky foreground), stretchedpolyethylene with a blue filter (the ocean and morning sky), and the fielddiaphragm image defocused (two exposures-the rising sun, and itsreflection photographed through a comb “diffraction grating”).

This leaf is a single exposure of a liquid crystalline solution of DNA. Asthe solution slowly evaporates, the DNA concentration increases and thesolution enters liquid crystalline states. This photomicrograph approxi-mates the state of DNA found in nature.

PHOTOgraphic 4

simply a blue or reddish morningsky. The blue sky is obtained byputting a blue filter in front of thefield lens (remember to leave inplace the mask that covers theprevious exposures) and remov-ing the polarizer. This places themicroscope in the brightfieldmode, which allows the blue lightto reach the film. Alternatively, tocreate a morning sky, cut a 1x2-inch section from a sandwichbaggie, and stretch the sectionbefore taping it onto a microscopeslide. The stretched baggie ismade of polyethylene molecules,which align when stretched toform a diffraction grating that actsas a prism, yielding the standardyellow-red-blue spectrum whenviewed through crossedpolarizers.

The next step in the sequence isan exposure for the sun or moon.This is done by defocusing theimage of the field diaphragm (aleaf-type shutter diaphragm whichallows light into the main tube ofthe microscope) until it appears asa circle. You can do this by

closing the lever for the dia-phragm until the individual leavesmerge into a small circle. Thenmove the main focus knob untilthe individual leaves becomeblurred and a complete circle witha fuzzy circumference appears.Next, place a yellow, orange, orred, (depending on the desiredeffect) filter in the light path. Atthis point, the diaphragm image

will be in the center of the field.You can move it to the upper rightor left by moving the centeringthumbscrews, which serve toposition the substage condenser.Remember to recenter the con-denser after the exposure.

Stars are obtained by superim-posing an image of very smallcrystallites over the previouslyexposed areas of the film. One ofthe most convenient ways ofmaking “star” crystallites is todissolve several vitamin-C tabletsin an ounce of rubbing alcohol(isopropanol). Place a drop ofsolution onto a microscope slideand allow it to dry slowly. As thealcohol dries, small crystallites ofvitamin C are formed, which canbe used to simulate stars in yourmicroscapes. Remember to maskall previous exposures beforeexposing the small crystallites.

By experimenting with avariety of recrystallized chemi-cals and filtering techniques, theamateur microscopist/photogra-pher can generate a wide varietyof unusual landscapes, as well asa collection of beautiful photomi-crographs of crystals.

How do you see relief? This kaleidoscopic image is a single single exposureof pain-reliever aspirin recrystallized from the melt.

“Feathers” was produced by a single exposure of the sugar arabinoserecrystallized from the melt.

PHOTOgraphic 5

“Bizarre Windows” is a single exposure ofabsorbic acid (vitamin C) recrystallized from moltenchemical.

“The Stand” consists of four exposures: recrystal-lized ascorbic acid (the plantlike structures foundin the foreground), a blue filter (the sky), tinyascorbic-acid crystallites (the stars), and the fielddiaphragm image defocused with a ballpoint peninserted into the light path to resemble a new moon.

“Lover’s Leap” is another quadruple exposure:recrystallized sulfur (the canyon), a blue filter (thesky), tiny ascorbic acid crystallites (the stars), andthe field diaphragm defocused with a yellow filter(the sun or moon).

Common chemicals suitable forrecrystallization.

CHEMICAL COMMENTS

Alka-Seltzer Best crystals from aqueoussolution.

Aspartame (Nutra-sweet) Good crystals from melt-recrystallization oraqueous solution.

Aspirin (acetylsalicylic acid) Equally good crystals frommelt-recrystallization oraqueous or ethanolsolutions.

Acetaminophen (Tylenol) Equally good crystals frommelt-recrystallization oraqueous solution.

Epsom salts Recrystallize from aqueoussolution only.

Glucose and sucrose Crystals quickly obtained(common sugars) by evaporation of solution

in water. Very beautifulcrystals after melt-crystallization.

Kodak Dektol paper developer Best crystals afterevaporation ofworking stock solution.

Kodak D-76 film developer Best crystals afterevaporation ofworking stock solution.

PHOTOgraphic 6

A single exposure of sulfur recrystallized from the melt produced this pattern.

OLYMPUS CORPORATION4 Nevada DriveLake Success, NY 11042Telephone: 516-488-3880

CAROLINA BIOLOGICALSUPPLY COMPANY2700 York RoadBurlington, NCTelephone: 800-334-5551

E. LEITZ, INC.24 Link DriveRockleigh, NJ 07647Telephone: 201-767-1100

CARL ZEISS, INC.One Ziess DriveThornwood, NY 10594Telephone: 914-747-1800

NIKON INC. INSTRUMENTGROUP623 Stewart Ave.Garden City, NY 11530Telephone: 516-222-0200

AO SCIENTIFICINSTRUMENTSP.O. Box 123Buffalo, NY 14240

FISHER SCIENTIFIC50 Fadem RoadSpringfield, NJ 07081Telephone: 201-379-1400

EXCEL TECHNOLOGIES90 Phoenix AvenueEnfield, CT 06082

EDMUND SCIENTIFIC CO.101 E. Gloucester PikeBarrington, NJ 08007Telephone: 609-573-6250

McCRONE ACCESSORIES ANDCOMPONENTS850 Pasquinelli Dr.Westmont, IL 60559Telephone: 312-887-7100

Microscope and accessory manufactures and distributors Michael W. Davidsonis a Research Associate atthe Institute or MolecularBiophysics at Florida StateUniversity.