REPRINTED FROM AMATEUR PHOTOGRAPHER

Alan McFaden puts the

Sigma 600mm mirror

lens through its paces.

I MA mm MIRROR LENS

IGMA HAS BEEN quick to supply an in­ dependent mirror lens to fit the Canon EOS. The lens will be especially useful as Canon has yet to release any 'Long Toms'. Canon's longest EF telephoto lens is a 300mm, so anything beyond this focal length is a

S

bonus. Mirror, or catadioptric, lenses such as the Sigma 600mm tend

to

have fixed apertures and

cannot be stopped down: these

lenses are typically designated 300mm f/5.6, 500-600mm f/8

and lOOOmm fIll. A conven­ tional telephoto of this focal length, with a range of f-stops, would be of enormous size and weight; mirror lenses are con­ veniently smaller and lighter. The unnerving thing about telephoto and mirror lenses is that there's no room for focusing

errors, as there is hardly any depth of field. The camera and lens must be held steady to focus and shoot because the

For £249.95 you get lens cap, hood, l!10oosec, which is essential to prevent camera shake. Also, case and five fi1te~e fifth /5 if the light levels were to drop already in position at the rear of the lens. the film could easily be pushed Telephone junction boxes also to ISO 800 or even 1600. However, I do recommend this provide good platforms, as do as a fair weather lens, bright walls, but put cloth or paper conditions giving acceptably under the camera to stop it fast shutter speeds with faster being scratched. A bean bag on any reasonably flat surface is films. The lens well on the body In theory a tripod should be also a great camera support. I 01 the Canon 650. Although used with this lens. Although was very lucky around the hamiheld shots are possible in the lens has a built-in tripod Westminster area, the council stronr IlghtinE while us!nr fast film decided to go for a walk around bush, in practice it is not always having obligingly supplied to rive adequately fast shutter London, a great place to take practical to use a tripod in busy several coin-operated tele­ speeds, it's advisable to llit;Jch the photographs as there is so much places. There are other ways and scopes, each providing a flat lens to a tripod using its tripod bush. going on that there is almost a means of keeping the camera platform at the right height and tiniest movement can cause picture around every corner. And steady-thank heaven for lamp­ well sited for telephoto work. The Sigma 600mm is sup­ unsharpness due to the extreme­ with so many camera-laden posts and signposts! Most towns ly narrow angle of view-4 deg. tourists around you don't attract are liberally endowed with plied with filters. These need to I was glad to have the much attention. these, and holding the lens be fitted over the rear of the lens opportunity to try a 'cat' lens The film I used was T-Max firmly against such supports because the front of the lens is and was keen to use it for 400, which would enable me to should give sufficient steadi­ so wide. The red, yellow and unobtrusive candid portrlliture. I use a shutter speed of around ness if a tripod is not available. orange filters help to penetrate Amateur PhotogrophfJ< 'I'Ile September 5 1987

The front element is too la"e to make the use of conventional filters

pmctical, so rear.mountinllil~rs are supplied.

Candid shots can be picked out with this lens and isolated from cDnfusinf backffounds.

Aperture priority mode can be haze and give more contrast with monochrome subjects. The used , bot the shutter speed neutral density (NO) filter suggested would give six stops provided helps to reduce ex­ overexposure. As there are no posure if there is, say, a light contacts on the lens mount, the camera assumes it has a maxim· reading which calls for 1I4000sec at fl8 (not very um aperture of fll, so this f-stop likely) and the camera's fastest should be dialled in rather than flS. Manual mode can be also speed is only 1I 1 000~c. There is little point in using be used if fl l is chosen, but programmed, shutter priority this lens to attempt shots which can just as easily be had by and depth modes are of no use wa lking up closer to the subject with this fixed-aperture lens. Versions com patible with the with a normal lens. The 600mm offers a powerful means of Canon EOS and Minolta AF capturing pictures over a great SLRs are available, while those distance, and which have a dis­ that link with Pentax SFX and Olympus OM707 are in the tinc tly different 'look'. The most obvious effect is the pipeline. way subjects can be made to It is an ideal lens for faraway, stand out from their back­ inaccessible subjects. Paparazzi photographers will find it use fu l! grounds. This is helped by the It's handy for wildlife and very narrow depth of field, which is very effective for isolating sporting events too, where there portrait subjects. Another effect are restrictions on getting c lose is exaggerated perspective to the subject. where the distance Detween objects seems dramatically re­ duced. Because the mirror in lens: Sigma 600mm mirror lens the lens has the cenire blocked ApeltUre 13Ra:e: fl8 out, out of focus highlights in MinimulA focusinl: 2m photographs come out shaped Macro ratio; 1:3 like doughnut rings. This is the Filter size; 30.Smm, rear·mounted characteri stic which makes it lens Ilood; Supplied easy to spot when a mirror lens AnIle 01 view; 4deg Elements/a:rouIlS: 7 elements in has been used. 4 il:rOUPS Results with the Sigma 600mm turned out to be very Available fitS; Most major fittings in oon-AF. Currently sharp and of reasonable con· available in AF: trast. As it's Quite a lighllens for Minolta. Canon EOS its type I did not feel weighted Weilflt (£): 830g down after a day's shooting. lenilh )( diameter (mm): 122 )( 99 However, it was a shame that Price (approx); £250 the lens did not offer autofocus Distributor: CZ ScientifIC Instruments, PO Box 71, or complete auto exposure This shot of the top Df St Paul's cathedral fives an idea of the tlscl! of Borehamwood, Hertfordshire. Siems's lens; /he picture was taken from fTOuna level! operation.

DATA PANEl

SoJe UK Distributor

C.z. SCIENTIRC INSTRUMENTS LIMITED PO Box 43, 1 Elstree Way, Borehamwood, Herts. WD61NH

Telephone: 01-9531688

•

I mirror ·enses

Eight mi" or tenses (rom the inde­ p enden t tens manufectunus which comprise our Whic h Cho ice. Focill leng ths rllngtJ from 3 00mm up 6 00mm , though the 'standard ' f ocil/length is 5 00mm.

It' s over a year ago since we loo k a close look at a batch of mirro r lenses and the market has develo ped co nsiderably si nce then . The len~cs tested then were the Cannon, T
it. The lens ~o m cs with a ki t o f fi ve ti llers: a IA s kylight, ne utral de nsit y 4X, yellow 52. orange 56 and red 60. These are 22.5m(\l in size a nd screw into the ba.::k of the lens. 10 Ihc inst ruction I.....d fl .:t accom panying the lens, Sigma ad vise thaI Ih~ kns should be used with a filh:f in all the time. This is be.;ause the upti..:al dc:.ign o f the lens includes the filler aod wilho ut One in place a focus s hift and dro p in resolutio n can be expec ted . They also advise against USing other fi llers o n Ihe front of Ihe le ns for Ihe same reason. I n a piece oi equipment whe re focusi ng a nd acc uracy is oi the absolute essence, it 's gooo to see the cOl11pani~ o ffering this sort o f information a nd ad vice; it 's Ihe iII-info rmcd or ignorant us.:r of t he equipment who sufkrs the ~

Filt ers for mirror IttnS8S 11(11 inv8ri8b1y sm./lllnd slot into the back of (he Hms. In this casll rhe skylight 1A filter is pvshad into the Pan.gor lenS,

MIRROR LENSES - OUR CHOICE TAMRON SP saOmm fl8 _?HNA_~. 300mm f1S.6 SIGMA ----­600mm _ . _ .fl8 . SUNAGOR 500mm fla TOKINA 500mm f /8 OHNAR 500mm ffS ~y PE!'I-""-~AgON

PERFORMANCE

- ­ VERY GOOD .. VERY GOODGOOO ._.­

---­ GOOD

SOOmm f/8 GOOD

PANAGOR 500mm tiS

AVERAGE

-­ -

-

-­

-_.

most from bad ':.:'",: 11$. , With the longest 1'01.111 il!n t!l h, Sig ma's {em is ve ry com~l ili ­ vely priced against the ,horler SOOmm lellsc~. Ddlnition was good 31 both centre a nd edge, for which the balance of aber· ralions was given a '/try good rating. Overall, a good (en~.

HOW THEY FARED AU ill aU, the mirror lenses under scrutin y performed well and there won no obviously poor quality products, Indeed, such a solid group as they turned o ut to be, there wasn' t much to Idl between them at t he end of t he da y. All will give good u.sage.­ The majo r bugbear of mirror leoses i5 not so much the fixed aperture - neut ral densi t y !il­ te rs a re usually provided to com· pensate for exposure prob lems - but Ihe problem or camera s ha ke, This was such as to ro rce us to a bandon o ur normal 'ship' pictures. The next choice was a churc h [o we r nea r o ur offices which was photographed thrOui h an open window, but o nce again vibrations were a proble m . Eventually the equipment wa:> leSled o ut in our sludios a nd a line d ra wing of a n ae ro plane was (,..h osel) as the subject. This \Vas sho t a t a distance of approxi· mately eight meltcs, but closcr ror the JOOmm mirro r le ns . Lighting was provided by el«· Itonic n ash - [ 0 completely eli· minate camera shake - a nd Ihe pi.::tures were shol on Pan F, 50ASA. t3est of the bunch was un · doubtedly the Tam ron S P 500mm, Good to use, nicely packaged a nd giving very good oplicai quali ty, il was noticea bly belief than the rest. SUI a t £100, you pay fvr il. Closely behind the;: Tamron Wi.) the O hnar JOOmm lens. Thi!> .:an be hand·hdd and is idea l fo r sponing event~. Recaili ng fo r aro und £75·£80, it's easily thr: chcapcSI of the {en scs we checked out. Expecl to see this size mirror ,lens be.::oming a n in.;:reasing fe31ure or' new equip· mC'nI trcnds. Of the good {ensts, the Sigma 600mm was thc ~t. This lens gives [he C'Xlra HXlmm in lo.:a! kng[h and Il)I.:uS
LENS PERFORMANCE

LENS PERFORMANCE POO(

PANAGOl15O(1

OveralllWrlOlm3l1ce Definition

Image tr: 20403 Disrdbu/or: Bush and MtiSSMT Li d , 136-144 GnlJwille Rd, Lortdon. NW).

.-

Lid, 136-144 Lo ndon, NW3.

LENS PERFORMANCE

SUPER PARAGON 600

perlOtm.nce Definition

Owf.U

Fai,

AVIllf{je

Imil't COnl'Ut

8alilnce of abell'lions

. , "' ,. 1 1

,

Good

• •• •

V"'_

tA M AON SP 500

Poor

Fair

•••

D.finition 1/TWIge conUUl

,'i,

Phulax

Rd ,

E;