The Medium For­mat D-SLR You Can't Af­ford To Ig­nore

ProPhoto - - FRONT PAGE - Re­poRt by paul buR­Rows

The 645D set the stan­dard for af­ford­abil­ity in dig­i­tal medium for­mat cam­era sys­tems and now the 645Z re­de­fines it cour­tesy of its new CMOS sen­sor and next-gen pro­ces­sor.

In the lIght of what’s avaIl­able in D-SLRs with full-35mm size sen­sors, mov­ing up to dig­i­tal medium for­mat can be a bit hard to jus­tify for many pho­tog­ra­phers, but it’s now more dif­fi­cult to ig­nore be­cause the Pen­tax 645Z looks like the goods on so many lev­els.

The orig­i­nal 645D was the most af­ford­able medium for­mat D-SLR cam­era on the mar­ket by a sig­nif­i­cant mar­gin and it’s al­ways been a bit of a mys­tery why Pen­tax wasn’t over­run by ea­ger buy­ers wav­ing credit cards… ex­cept, ac­tu­ally, there prob­a­bly where a cou­ple of rea­sons. For any­body se­ri­ously in the mar­ket for a dig­i­tal medium for­mat cam­era sys­tem, the 645D was se­verely limited be­cause it es­sen­tially didn’t have a sys­tem… of lenses, that is. Ri­coh – which now runs the Pen­tax show – has ad­dressed this by mak­ing the fuller sys­tem of lenses more widely avail­able out­side Ja­pan. So now there’s a choice of 17, in­clud­ing five zooms (with three more to come). That said, quite a num­ber of th­ese date back to the 645 film sys­tem so they lack the newer dig­i­tal-era DFAseries fea­tures such as the SDM built-in fo­cus­ing mo­tors, weather-proof­ing and im­age sta­bil­i­sa­tion.

In terms of at­tract­ing users more ac­cus­tomed to the lux­u­ries of ‘APS-C’ and full-35mm D-SLRs, the 645D went a long way to closing the gap, but per­haps not far enough for some. Here the 645Z is now not only the best-fea­tured dig­i­tal medium for­mat cam­era on the mar­ket – again by a sig­nif­i­cant mar­gin – but its sys­tems and fea­tures are com­pa­ra­ble with the pro-level ‘APS-C’ and full-35mm for­mat cam­eras cur­rently avail­able. It’s still more ex­pen­sive that the Canon EOS-1D X and Nikon D4S – both of which blow it out of the wa­ter in terms of speed – but if the pur­suit of im­age qual­ity is a more im­por­tant con­sid­er­a­tion then hav­ing a sen­sor that’s 1.7x times larger than a full-35mm imager – and in the or­der of 2.5x larger than ‘APS-C’ – is a good place to start.

The big­gest change is the adop­tion of a CMOS-type sen­sor for the 645Z, and the sig­nif­i­cance of this is that it en­ables, among other things, faster con­tin­u­ous shoot­ing speeds, live view and Full HD video record­ing. There’s a CMOS-driven revo­lu­tion go­ing on at the mo­ment in dig­i­tal medium for­mat, mostly thanks to Sony’s devel­op­ment of a ‘645’ for­mat sen­sor which is also be­ing used by

The 645Z is now not only the best-fea­tured dig­i­tal medium for­mat cam­era on the mar­ket, but its sys­tems and fea­tures are com­pa­ra­ble with the pro-level ‘APS-C’ and full-35mm for­mat cam­eras cur­rently avail­able.

Has­sel­blad, Phase One and Mamiya Leaf in var­i­ous prod­ucts. All th­ese man­u­fac­tur­ers recog­nise the need to make dig­i­tal medium for­mat more at­trac­tive given the re­cent pace of devel­op­ment in the smaller for­mats.

How­ever, the 645Z fur­ther builds on the ma­jor CMOS-de­rived per­for­mance en­hance­ments by in­her­it­ing most of the ad­vanced con­trol sys­tems and fea­tures from the Pen­tax K-3, Ri­coh’s cur­rent ‘APS-C’ D-SLR flag­ship. It’s a luxury no other maker of dig­i­tal medium for­mat cam­era sys­tems has, and it turns the 645Z into a truly for­mi­da­ble ma­chine. OK, so it’s still quite pricey even com­pared with a pro-level D-SLR with a full-35mm sen­sor, but now that the 645Z is com­pa­ra­ble in terms of its ca­pa­bil­i­ties, it can com­pete more con­vinc­ingly on the per­for­mance benefits of its big­ger imager with its sig­nif­i­cantly higher res­o­lu­tion.

Pixel Power

Es­sen­tially the same de­vice as Has­sel­blad uses in the H5D-50c cam­era and the CFV-50c cap­ture back, and Phase One uses in its IQ150 and IQ250 backs, the 645Z’s CMOS sen­sor has an imag­ing area of 43.8x32.8 mm and a to­tal pixel count of 52.99 megapix­els (cop that, Nikon D810!). The ef­fec­tive pixel count is still a mas­sive 51.4 MP which de­liv­ers a max­i­mum im­age size of 8256x6192 pix­els. The pixel size is 5.3 mi­crons which helps con­trib­ute to a dy­namic range of 14 stops and a na­tive sen­si­tiv­ity range equiv­a­lent to ISO 100 all the way to 204,800… and that max­i­mum is achieved with­out any ex­pan­sion pro­cess­ing which is sig­nif­i­cant.

Fur­ther­more, Pen­tax makes sure ev­ery drop of res­o­lu­tion is squeezed out of this sen­sor by not us­ing a low-pass fil­ter. In­stead, the 645Z has the same ‘AA Fil­ter Sim­u­la­tor’ sys­tem as the K-3 and which is a me­chan­i­cal so­lu­tion us­ing sen­sor shift­ing.

Es­sen­tially work­ing in the re­verse to im­age sta­bil­i­sa­tion, the sen­sor is shifted very frac­tion­ally in or­der to in­tro­duce the slight blur­ring or ‘fil­ter­ing’ needed to counter moiré pat­terns. There are three set­tings – ‘Off’ which is ob­vi­ously for pri­ori­tis­ing res­o­lu­tion; ‘Type 1’ which is de­signed to bal­ance res­o­lu­tion and moiré cor­rec­tion by shift­ing the sen­sor in a lin­ear di­rec­tion; and ‘Type 2’ which os­cil­lates the sen­sor in a cir­cu­lar mo­tion in or­der to op­ti­mise the blur­ring ef­fect

and, as a re­sult, moiré cor­rec­tion. The im­age cap­ture op­tions com­prise JPEGs in one of four sizes and three com­pres­sion lev­els, 14-bit RGB RAW files as ei­ther Adobe DNG or PEF, and TIFFs. RAW+JPEG cap­ture can be con­fig­ured for any JPEG size and qual­ity set­ting. The new sen­sor is mated with Pen­tax’s lat­est-gen­er­a­tion ‘PRIME III’ pro­ces­sor (as used in the K-3) which is claimed to be five times faster than the pre­vi­ous en­gine so it also helps con­trib­ute to a faster shoot­ing speed. OK, so 3.0 fps may not seem earth­shat­ter­ing com­pared to the rapid-fire full-35mm D-SLRs, but it’s still fast for a dig­i­tal medium for­mat cam­era and nearly three times faster than the 645D. And the burst lengths are quite re­spectable – 30 frames with JPEG/large/best cap­ture and ten in RAW mode.

The 645Z re­tains dual SD mem­ory card slots as be­fore, but now sup­ports SDXC types as well as UHS-I speed data trans­fer plus Eye-Fi and FLU cards for wire­less data trans­mis­sion. The two slots can be set up in a va­ri­ety of ways, in­clud­ing si­mul­ta­ne­ous sav­ing to both (which cre­ates a back-up) or the sep­a­rate sav­ing of RAW files and JPEGs. It’s also pos­si­ble to copy images from one card to an­other.

As noted at the out­set, the 645Z can also record video and it uses close to the whole sen­sor for this (a small outer area is re­served for elec­tronic im­age sta­bil­i­sa­tion) so the depth-of-field can be even shal­lower than it is with a full-35mm or ‘APS-C’ which should have some video-mak­ers drool­ing. It’s the first dig­i­tal medium for­mat cam­era with Full HD video record­ing.

Big Views

An­other ma­jor ben­e­fit of switch­ing to a CMOS sen­sor is live view, and the 645Z makes the most of this by switch­ing from a fixed LCD mon­i­tor screen to one that’s ad­justable for tilt, ei­ther up to down… which is ac­tu­ally a first for any Pen­tax D-SLR. Ad­di­tion­ally, it’s the big­ger, 8.1 cm, 3:2 as­pect ra­tio TFT LCD panel from the K-3 with a res­o­lu­tion of 1.037 megadots and ad­justable for bright­ness, colour bal­ance and colour sat­u­ra­tion.

Un­changed from the 645D is the op­ti­cal viewfinder which em­ploys a trape­zoid­shaped pen­taprism – be­cause it’s more com­pact than a con­ven­tional type – and pro­vides a 98-per­cent sub­ject cov­er­age. The stan­dard ‘Nat­u­ral Bright Matte’ fo­cus- ing screen can be in­ter­changed with one of four al­ter­na­tives and it’s an easy D-I-Y pro­ce­dure. Even com­pared to a full-35mm D-SLR, the 645Z’s viewfinder is truly huge and quickly ad­dic­tive so that any­thing smaller starts to feel quite claus­tro­pho­bic.

As with its pre­de­ces­sor, the 645Z looks quite im­pos­ing, but in terms of its over­all bulk, it’s not vastly dif­fer­ent from Nikon’s D4S or Canon’s EOS-1DX. The sub­stan­tial hand­grip is com­fort­able to hold, but this is def­i­nitely a two-handed cam­era even with one of the sys­tem’s smaller lenses fit­ted. The con­trol lay­out is based around a main mode dial with front and rear in­put wheels and var­i­ous func­tion but­tons. On the hand­grip side th­ese are for sen­si­tiv­ity, ex­po­sure com­pen­sa­tion and the AE lock while, on the op­po­site side of the pen­taprism hous­ing is a lineup of four but­tons for the AF area modes, in­stant switch­ing to RAW cap­ture, set­ting up the auto ex­po­sure brack­et­ing and lock­ing the rear in­put wheel.

Most of the top deck is taken up with a huge mono­chrome read-out panel which is an­gled to­wards the user. There’s a new – well, ac­tu­ally re­pur­posed

– se­lec­tor for switch­ing be­tween still photography and video shoot­ing plus, on the rear panel, a new but­ton for ei­ther en­gag­ing live view or, in the video mode, start­ing and stop­ping record­ing.

The rear panel lay­out is ac­tu­ally quite sim­i­lar to that of the K-3 so it’s cen­tred around a four-way key­pad which is for all nav­i­ga­tional du­ties – in­clud­ing mov­ing the fo­cus point – but then each of the keys also have their own func­tions – pro­vid­ing di­rect ac­cess to the drive modes, white bal­ance set­tings, flash modes and ‘Cus­tom Im­age’ pre­sets (more about th­ese shortly). Press­ing an ad­ja­cent but­ton switches them be­tween AF point duty and their other roles. As on the K-3, there’s a Sta­tus Screen dis­play in the main mon­i­tor – show­ing all the main AF and AE set­tings – and a Con­trol Screen which gives quick ac­cess to a range of func­tions for ad­just­ment. An­other op­tion here is a dual-axis ‘ar­ti­fi­cial hori­zon’ level dis­play (less in­tru­sive bar-type level dis­plays are pro­vided in live view).

Tak­ing Con­trol

The 645Z’s bodyshell com­prises all mag­ne­sium al­loy cov­ers with a to­tal of 76 seals to pro­tect against the in­tru­sion of mois­ture or dust. Ad­di­tion­ally, the body is in­su­lated in key ar­eas such as the bat­tery com­part­ment to en­able op­er­a­tion to con­tinue down to -10 de­grees Cel­sius. Un­der­neath is a diecast alu­minium chas­sis and the lens mount is stain­less steel.

Un­doubt­edly the 645D was held back by the very limited choice of lenses, but now a num­ber of the Ja­pan-only mod­els have been made more widely avail­able.

The 645Z’s con­trol sys­tems are es­sen­tially bor­rowed lock, stock and bar­rel from the K-3, start­ing with its 86,000 pix­els RGB-sen­si­tive me­ter­ing sen­sor. In con­junc­tion with the AF sys­tem, this de­liv­ers what Pen­tax calls ‘Real Time Scene Anal­y­sis’ me­ter­ing which is de­signed to de­ter­mine most ap­pro­pri­ate me­ter­ing weight­ing for a given sub­ject or scene (ex­actly like Nikon’s ‘Scene Recog­ni­tion Sys­tem’). There’s the op­tion of cen­treweighted av­er­age or spot mea­sure­ments.

As on the K-3, Pen­tax sup­ple­ments the stan­dard choice of ‘PASM’ ex­po­sure con­trol modes with a cou­ple of dif­fer­ent ways of do­ing things. The first is Sen­si­tiv­i­tyPri­or­ity AE – marked as ‘Sv’ on the mode dial – which al­lows for the ISO set­ting to be changed on-the-fly via the 645Z’s rear in­put wheel and the ex­po­sure set­tings are then changed ac­cord­ingly.

The sec­ond is called Shut­ter & Aper­ture-Pri­or­ity AE – marked ‘TAv’ on the mode dial – and it’s es­sen­tially an auto ISO con­trol in that the ISO set­ting is au­to­mat­i­cally changed in or­der to main­tain a par­tic­u­lar com­bi­na­tion of aper­ture and shut­ter speed as light lev­els vary. The pro­gram ex­po­sure mode can be cus­tomised via a se­lec­tion of six aper­ture/speed se­lec­tion lines, namely Auto, Nor­mal, High Speed Pri­or­ity, Depth-Of-Field Pri­or­ity – Deep, Depth-Of-Field Pri­or­ity – Shal­low and MTF Pri­or­ity. Th­ese are all pretty self­ex­plana­tory, but the MTF Pri­or­ity set­ting op­ti­mises the aper­ture se­lec­tion to match the at­tached lens’s MTF curve (as ob­tained from the lens’s CPU). Pro­gram shift is pos­si­ble in all set­tings and with ei­ther aper­ture or shut­ter speed pri­or­ity, depend­ing on whether the front or rear in­put wheel is used. There’s also the op­tion of ‘Hy­per’ switch­ing in both the pro­gram and man­ual modes. In pro­gram mode, turn­ing the ap­pro­pri­ate con­trol wheel au­to­mat­i­cally switches the 645Z to ei­ther aper­ture-pri­or­ity or shut­ter-pri­or­ity auto op­er­a­tion… and the info dis­play changes, for ex­am­ple, from ‘P’ to ‘Hy­per Av’. In man­ual mode, press­ing the ‘green-dot’ but­ton on the cam­era’s back panel sets the ex­po­sure as it would be determined in the pro­gram mode and this can then be used as the start­ing point for fine-tun­ing.

The auto and semi-auto ex­po­sure con­trol modes are backed by an AE lock, com­pen­sa­tion up to +/-5.0 EV and auto brack­et­ing which can be set to op­er­ate over se­quences of two, three or five frames with an ad­just­ment of up to +/2.0 EV per frame. The 645Z’s shut­ter has a speed range of 30-1/4000 sec­ond and its dura­bil­ity has been ex­tended to 100,000 cy­cles, twice the pre­vi­ous quoted life­span. Flash sync is at all speeds up to 1/125 sec­ond, but the 645Z doesn’t have a built-in flash. Ex­ter­nal flash units sync via a hot­shoe or a PC flash ter­mi­nal.

Sharp Shoot­ing

The aut­o­fo­cus sys­tem is based on the ‘SAFOX 11’ mod­ule – as in­tro­duced in the K-3 – and em­ploys a to­tal of 27 fo­cus­ing points, 25 of them cross-type ar­rays ar­ranged in a 5x5 pat­tern. Given the larger frame area, th­ese cover a smaller patch than they do in the K-3, but this is still the most so­phis­ti­cated AF sys­tem in the medium for­mat world by far.

Three of the points in the very cen­tre of the frame (ar­ranged ver­ti­cally) work with f2.8 speed lenses and the sys­tem’s the sen­si­tiv­ity extends down to EV -3.0 (at ISO 100). Low light as­sist is pro­vided by a built-in LED il­lu­mi­na­tor. Switch­ing be­tween sin­gle-shot and con­tin­u­ous op­er­a­tion is done man­u­ally and there’s an ex­ten­sive choice of AF area modes with auto point se­lec­tion over one, nine or the full 27 points and man­ual point se­lec­tion over one, nine, 20 or the full 27 points. In each case, the point clus­ters can be moved around us­ing the nav­i­ga­tor key­pad.

Fur­ther­more, in the Cus­tom menu, the sin­gle-shot AF mode can be set to ei­ther fo­cus-pri­or­ity or re­lease-pri­or­ity (i.e. the shut­ter will still fire even if the sub­ject isn’t in fo­cus) while the con­tin­u­ous AF mode can be set to fo­cus-pri­or­ity, fps-pri­or­ity or auto switch­ing be­tween the two. It’s also pos­si­ble to de­ter­mine con­tin­u­ous AF op­er­a­tion for the first frame – again fo­cus-pri­or­ity, re­leasepri­or­ity or auto switch­ing. Fo­cus­ing track­ing is sup­ple­mented with a ‘Hold AF’ ad­just­ment – also found in the Cus­tom menu – which has four set­tings from ‘Off’ to ‘High’ to vary whether the sys­tem stays locked on to the sub­ject re­gard­less or will re­fo­cus on a new sub­ject, depend­ing on the pe­riod of in­ter­rup­tion.

In live view or when shoot­ing video, the 645Z re­lies on con­trast de­tec­tion mea­sure­ments from the sen­sor which of­ten makes man­ual ad­just­ment the more at­trac­tive op­tion so, to as­sist here, there’s a fo­cus­ing peak­ing dis­play to pro­vide as­sis­tance along with a mag­ni­fied im­age.

The white bal­ance con­trol op­tions in­clude the ‘Multi Auto WB’ mea­sure­ment which is also on the K-3, but was orig­i­nally de­vised by Ri­coh for CX Se­ries high­erend com­pacts and the GXR. This em­ploys multi-point mea­sure­ment to bet­ter han­dle scenes which in­clude a num­ber of dif­fer­ent light source, es­sen­tially by de­ter­min­ing an av­er­age colour tem­per­a­ture. Ad­di­tion­ally, the 645Z also has Pen­tax’s ‘Colour Tem­per­a­ture En­hance­ment’ (CTE) auto mode which in­creases the pre­dom­i­nant colour in an im­age rather than try­ing to cor­rect for it. There is a to­tal of nine white bal­ance pre­sets – in­clud­ing four for dif­fer­ent types of flu­o­res­cent light­ing – and pro­vi­sions for stor­ing up to three cus­tom mea­sure­ments. Three man­ual colour tem­per­a­ture set­tings – se­lected from a range of 2000 to 10,000 de­grees Kelvin – can also be stored. Fine-tun­ing in the blue-to-am­ber or ma­genta-to-green colour ranges – over a range plus/mi­nus seven steps – is avail­able for all the WB pre­sets, the cus­tom set­tings, the man­ual set­tings, and both the CTE and Multi Auto modes. How­ever, as is also the case with the K-3, the 645Z doesn’t have a white bal­ance brack­et­ing func­tion.

The 645Z fur­ther builds on the ma­jor CMOSderived per­for­mance en­hance­ments by in­her­it­ing most of the ad­vanced con­trol sys­tems and fea­tures from the Pen­tax K-3, Ri­coh’s cur­rent ‘APS-C’ D-SLR flag­ship.

In The Pic­ture

Also bor­rowed from the K-3 is a rea­son­able se­lec­tion of op­tions for pro­cess­ing JPEGs which again makes the 645Z unique in the dig­i­tal medium for­mat world where the ex­is­tence of JPEGs is barely ac­knowl­edged, if at all. So the 645Z has a to­tal of 11 ‘Cus­tom Im­age’ pic­ture pre­sets which is one more than the K-3, due to the ad­di­tion of a new one called Ra­di­ant. This joins a list that com­prises Bright, Nat­u­ral, Por­trait, Land­scape, Vi­brant, Muted, Bleach By­pass, Re­ver­sal Film, Mono­chrome and Cross Pro­cess­ing.

Each of the stan­dard colour modes is ad­justable for sat­u­ra­tion, hue, sharp­ness, con­trast and high/low key. This last pa­ram­e­ter varies the im­age bright­ness over a range of plus/mi­nus four steps. Ad­just­ments to both colour sat­u­ra­tion and hue are made within a RGBCMY colour hexagon dis­play which shows the vari­a­tions in colour space terms.

The Bleach By­pass pre­set re­places the hue ad­just­ment with a range of eight coloured ton­ing ef­fects (with green as the de­fault) while the Re­ver­sal Film pre­set only has an ad­just­ment for sharp­ness, but the colour sat­u­ra­tion and con­trast are al­ready boosted to repli­cate the look of trans­parency film. The Cross Pro­cess­ing mode has a Ran­dom set­ting, a choice of three pre­set ef­fects and pro­vi­sions for stor­ing three favourite ef­fects.

The Mono­chrome ‘Cus­tom Im­age’ has ad­just­ments for sharp­ness, con­trast and high/low key plus a set of con­trast fil­ters and a se­lec­tion of ton­ing af­fects. The fil­ters are yel­low, or­ange, red, green, ma­genta, blue, cyan and infrared while the ton­ing ef­fects range from cold-to­warm (i.e. blue-to-sepia) over plus/mi­nus four steps. The vis­ual ef­fects of each pre­set – and any fine-tun­ing – can be gauged via the cam­era’s ‘Dig­i­tal Pre­view’ func­tion which cap­tures a pre­view im­age and dis­plays it re­gard­less of whether live view is ac­ti­vated or not. This is done by flick­ing the power switch to a pre­view

po­si­tion (it can also be set for an op­ti­cal pre­view… a.k.a. depth-of-field pre­view) and you can then chose to save this im­age to a card or dis­card it.

Cre­ative Process

Un­like the K-3, the 645Z doesn’t have any dig­i­tal fil­ters or spe­cial ef­fects that are avail­able for ap­pli­ca­tion at the point of cap­ture, but there’s an im­pres­sive col­lec­tion of 19 avail­able for post­cap­ture pro­cess­ing.

Th­ese in­clude the usual sus­pects such as Toy Cam­era, Retro, Minia­ture, Soft, Fish-Eye, Pas­tel, Sketch and Pos­ter­i­sa­tion plus oth­ers such as Shad­ing, In­vert Colour, Uni­colour Bold and Bold Mono­chrome. There’s also a ‘Base Pa­ram­e­ter Ad­just’ set­ting which en­ables the im­age’s base bright­ness, sat­u­ra­tion, hue, con­trast and sharp­ness to be fine-tuned. In­ci­den­tally, th­ese var­i­ous ef­fects can also be ap­pended to a RAW file and sub­se­quently ap­plied when the im­age is pro­cessed post-cam­era.

Multi-shot HDR cap­ture is avail­able and records three frames with a choice of ad­justable brack­et­ing val­ues from +/-1.0 to +/-3.0, auto ad­just­ment or three ‘strength’ set­tings called HDR1, HDR2 and HDR3. There’s also an ‘Auto Align’ cor­rec­tion to en­sure the three frames are pre­cisely matched. More im­por­tantly for some users, HDR cap­ture is pos­si­ble when shoot­ing RAW – ei­ther PEF or DNG files – with the three com­po­nent images saved in a sin­gle file.

Al­ter­na­tively, the 645Z has dy­namic range ex­pan­sion pro­cess­ing with sep­a­rate ad­just­ments for the high­lights and the shad­ows, both with an Auto cor­rec­tion op­tion. The ‘D-Range’ cor­rec­tions are per­formed via a com­bi­na­tion of ex­po­sure ad­just­ments for the high­lights and an ad­just­ment of the tone curve for the shad­ows.

There’s also a mul­ti­ple ex­po­sure fa­cil­ity which can cap­ture up to 2000 shots with the choice of three com­pos­ite modes to de­ter­mine the over­all ex­po­sure – Av­er­age, Ad­di­tive or Bright. An in­ter­val­ome­ter also al­lows for up to 2000 images to be cap­tured over in­ter­vals of two sec­onds up to 24 hours.

On Dis­play

We men­tioned the 645Z mon­i­tor-based info dis­plays ear­lier, but it’s worth a men­tion here that there’s a choice of no fewer than 12 colour schemes, in­clud­ing – if you so de­sire – yel­low, or­ange, pur­ple or green.

The live view screen can be con­fig­ured to in­clude a real-time his­togram, a high­light warn­ing, one of five grid pat­terns, the bar-type elec­tronic level dis­plays men­tioned ear­lier and an ex­po­sure com­pen­sa­tion scale. The ‘Cus­tom Im­age’ pic­ture modes, white bal­ance set­tings and drive modes can all be di­rectly ac­cessed when the cam­era is in live view and ob­vi­ously the ‘Dig­i­tal Pre­view’ func­tion is avail­able.

The im­age re­view/play­back the screens in­clude a lu­mi­nance his­togram su­per­im­posed over the im­age, a thumb­nail with a full set of his­tograms (i.e. lu­mi­nance plus the RGB chan­nels), both high­light and shadow warn­ings, the grid dis­plays and a de­tailed set of Exif data. The play­back edit­ing func­tions in­clude crop­ping and re­siz­ing, ba­sic movie edit­ing, the abil­ity to save a white bal­ance set­ting, copy­ing images from one mem­ory card to the other, and a slide show func­tion which al­lows for vari­able dis­play times and a se­lec­tion of three tran­si­tional ef­fects. Also here is a ‘Colour Moiré Cor­rec­tion’ fa­cil­ity with three strength set­tings, and in-cam­era RAW file con­ver­sion to ei­ther a JPEG or a TIFF.

Thumb­nails can be dis­played in groups of six, 12, 20, 35 or 80 images, or in a ‘Cal­en­dar Film­strip’ dis­play. At the other end of the size scale, zoom play­back al­lows for im­age mag­ni­fi­ca­tion of up to 16x and a ‘Quick Zoom’ func­tion can be set to go straight to 2x, 4x, 8x or 16x . Copy­right in­for­ma­tion can be added to the Exif data, namely the pho­tog­ra­pher’s name and that of the copy­right holder.

Pen­tax car­ries over the menu sys­tem from its ‘APS-C’ D-SLRs to the 645Z so each chap­ter is di­vided into stand-alone pages which are in­di­vid­u­ally ac­cessed via num­bered tabs (i.e. there is no con­tin­u­ous scrolling). Both the lay­out and nav­i­ga­tion are fairly log­i­cal with re­peated right-clicks delv­ing into the sub-menus and set­tings, and then the ‘Menu’ but­ton for go­ing back­wards. One on­go­ing idio­syn­crasy is Pen­tax’s pol­icy of also us­ing the right-click key for check­ing some func­tions as well as the more log­i­cal ‘OK’ but­ton… so, if you are in the habit of sub­se­quently press­ing ‘OK’ to con­firm an ac­tion, you’ll ac­tu­ally end up switch­ing that func­tion off.

The idea of shoot­ing video with a medium for­mat D-SLR is an in­ter­est­ing one, but ob­vi­ously the big at­trac­tion is the even shal­lower depth- of-field in­her­ent in the big­ger sen­sor com­pared to full-35mm.

Mak­ing Movies

The idea of shoot­ing video with a medium for­mat D-SLR is an in­ter­est­ing one, but ob­vi­ously the big at­trac­tion is the even shal­lower depth-of-field in­her­ent in the big­ger sen­sor com­pared to full-35mm. And, of course, the older man­ual-fo­cus Pen­tax 645 film lenses aren’t an is­sue here ei­ther.

The 645Z records video us­ing MPEG-4 AVC/H.264 com­pres­sion in the .MOV for­mat and, at the Full HD res­o­lu­tion, there’s a choice of 50 fps in­ter­laced or 25 fps and 24 fps with pro­gres­sive scan (the NTSC stan­dard speeds are also avail­able). For HD record­ing, the choice is 50 fps, 25 fps or 24 fps pro­gres­sive scan. As noted in the main text, the 645Z has built-in stereo mi­cro­phones with the choice of auto lev­els con­trol or man­ual set­ting over a range of 20 steps. There’s also a 3.5 mm stereo au­dio in­put for con­nect­ing an ex­ter­nal mic, but un­like on the K-3, there isn’t a stereo au­dio out­put.

The cam­era’s movie mode is en­gaged via a se­lec­tor switch ad­ja­cent to the viewfinder eye­piece and there’s a record­ing start/stop but­ton on the back panel. You can spec­ify which mem­ory card is used for stor­ing the video clips and the func­tion­al­ity extends to the full set of ‘PASM’ ex­po­sure modes, con­tin­u­ous AF with track­ing, the ‘Cus­tom Im­age’ pre­sets, dy­namic range ex­pan­sion pro­cess­ing and elec­tronic im­age sta­bil­i­sa­tion. Aper­tures and speeds can be changed man­u­ally dur­ing record­ing, but not the ISO. Both the im­age mag­ni­fi­ca­tion and fo­cus peak­ing dis­play are avail­able to as­sist with man­ual fo­cus­ing.

Time lapse record­ing is also avail­able and at the 4K res­o­lu­tion of 3840x2160 pix­els too (with­out sound ob­vi­ously), but since Mo­tion JPEG com­pres­sion is used here, the re­sult­ing AVI files are huge.

Ri­coh has al­ways trod cau­tiously where video is con­cerned so it’s per­haps not sur­pris­ing that the 645Z doesn’t have ‘nor­mal’ con­tin­u­ous 4K shoot­ing which would have made it re­ally in­ter­est­ing… as would an un­com­pressed video feed to its HDMI con­nec­tor and aids such as a ze­bra pat­tern gen­er­a­tor. Con­se­quently, the at­trac­tions of the big­ger sen­sor aside, this is still pri­mar­ily a stills cam­era.

Per­for­mance And Speed

With our ref­er­ence mem­ory card – Lexar’s Pro­fes­sional 600x 64 GB SDXC UHS-I speed de­vice – loaded the 645Z cap­tured a burst of 34 JPEG/large/best frames in 11.401 sec­onds which rep­re­sents a con­tin­u­ous shoot­ing speed of 2.98 fps… as near as a whisker to the quoted 3.0 fps. For the record, the av­er­age file size was 30 MB so that’s a fair amount of data to move around, but the buf­fer mem­ory still emp­tied ex­tremely quickly. As we found, with a UHS-I speed card, the cam­era will go on shoot­ing be­yond the quoted burst length, but the frame rate is re­duced.

How­ever, it’s the imag­ing per­for­mance that seals the deal with the Pen­tax 645Z… this and the fact that it’s as easy to use as any ‘small for­mat’ D-SLR with com­pa­ra­ble AF and me­ter­ing per­for­mances. It may look im­pos­ing, but it han­dles beau­ti­fully and re­ally doesn’t feel all that big in the hand (although it might with a longer lens fit­ted). The im­age qual­ity is noth­ing short of stunning and, in many ways, it is just like look­ing at a 6x4.5cm trans­parency af­ter you’ve been ac­cus­tomed to 35mm. The best qual­ity JPEGs ex­hibit a level of de­tail­ing that’s truly dra­matic and ev­ery­thing stays crisply re­solved even with very big en­large­ments (just like medium for­mat film). Of course, it’s 51 MP res­o­lu­tion that’s also un­fet­tered by an anti-alias­ing fil­ter so the amount of crisply-re­solved de­tails has to be seen to be be­lieved.

The dy­namic range is also ex­cep­tional and stays im­pres­sive even at the higher ISOs up to 6400. Noise re­ally isn’t an is­sue up to ISO 3200 and even the ISO 6400 and 12,800 set­tings are quite use­able, although some grain­i­ness is ev­i­dent in ar­eas of uni­form tone. Be­cause the 645Z is so com­fort­able to use hand-held, the imag­ing per­for­mance be­tween ISO 100 and 1000 means you can do this in a wide range of light­ing sit­u­a­tions (which is where the TAv ex­po­sure mode re­ally comes into its own). The set­tings be­yond ISO 51,200 re­ally are only there for brag­ging rights as they’re very noisy. Nev­er­the­less, the 645Z still puts in a very su­pe­rior high ISO per­for­mance in­deed. The var­i­ous ‘Cus­tom Im­age’ pre­sets pro­vide plenty of scope for tweak­ing colour and sharp­ness when shoot­ing JPEGs. The tonal gra­da­tions are su­per smooth and the sub­tlest of shades is han­dled as well as the fully sat­u­rated. There re­ally is no as­pect of the 645Z’s imag­ing per­for­mance that isn’t wor­thy of a su­perla­tive and this cer­tainly goes some way to jus­ti­fy­ing the pur­chase price.

The Ver­dict

In the light of cam­eras with full-35mm sen­sors like Nikon’s D810 or Sony’s Al­pha A7R, it can be hard to mount a com­pelling ar­gu­ment for dig­i­tal medium for­mat, but the Pen­tax 645Z is un­doubt­edly that ar­gu­ment. Apart from be­ing the most af­ford­able medium for­mat D-SLR on the mar­ket by a long shot, it’s also the most user-friendly and the most ca­pa­ble,

par­tic­u­larly if you want the con­ve­nience of shoot­ing JPEGs. It han­dles as com­fort­ably as any full-35mm D-SLR and is equally com­pa­ra­ble in terms of its op­er­a­tional ease and ef­fi­ciency. The re­li­able aut­o­fo­cus­ing op­er­a­tion, faster shoot­ing speed, tiltable mon­i­tor and video ca­pa­bil­i­ties also put the 645Z in a class of its own, but tow­er­ing above all this is its awe-inspiring imag­ing qual­ity. Here the Pen­tax out­per­forms any­thing with a full-35mm sen­sor – yes, even the D810 – yet it costs very much less than any of its ri­vals with 50 MP CMOS imagers.

On bal­ance then, the Pen­tax 645Z sim­ply can’t be de­fined by its price tag alone be­cause this pales into in­signif­i­cance in the light of ev­ery­thing this cam­era of­fers for that money. By that test, noth­ing else on the mar­ket – in any sen­sor for­mat – comes close.

The 645Z may look im­pos­ing, but it ac­tu­ally han­dles very com­fort­ably.

The con­trol lay­out is very sim­i­lar to that of any smaller for­mat D-SLR and cen­tres around the main mode dial and front/rear in­put wheels.

Ex­tra ‘Sv’ and ‘TAv’ ex­po­sure con­trol modes bor­rowed from Pen­tax’s ‘APS-C’ D-SLRs. Se­lec­tor switch be­low is for the me­ter­ing modes.

The rear con­trol lay­out is very sim­i­lar to that of the ‘APS-C’ for­mat K-3.

The re­vised func­tion but­ton lay­out on the left side of the viewfinder now in­cludes one for se­lect­ing the AF area modes.

Mas­sive LCD read- out panel sup­ple­ments mon­i­tor-based dis­plays.

LCD mon­i­tor screen has tilt ad­just­ments. It’s both big­ger and has a higher res­o­lu­tion than the 645D’s panel.

Built-in mics have auto and man­ual level con­trol, the lat­ter over 20 steps.

Dual card slots sup­port SDHC and SDXC de­vices with UHS-I speed data trans­fer. Eye-fi and FLU wire­less cards can also be used.

The con­nec­tion bay in­cludes USB 3 ‘Su­perSpeed’, HDMI and a stereo au­dio in­put.

Menu de­sign is the same as that used in Pen­tax’s ‘APS-C’ D-SLRs with self- con­tained pages within each sec­tion.

Con­trol Screen pro­vides quick ac­cess to a range of func­tions in both the still and video modes.

Sub-menus are ac­cessed via a right click. Shown here are the pro­gram line op­tions.

Mon­i­tor-based info dis­play can be set to one of 12 colour schemes. We par­tic­u­larly like the yel­low shown here.

The bodyshell com­prises mag­ne­sium al­loy cov­ers and is both sealed and in­su­lated.

Live view dis­play com­po­nents in­clude a real­time his­togram, dual-axis level in­di­ca­tors (top right cor­ner), grid pat­terns and ex­po­sure level/ com­pen­sa­tion scale.

Im­age re­view screens in­clude (above) bright­ness his­togram, cap­ture data or RGB his­tograms.

Pen­tax’s sec­ond­gen­er­a­tion medium for­mat D-SLR joins the CMOS sen­sor club and gains a num­ber of new fea­tures as a re­sult, in­clud­ing Full HD video record­ing.

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.