Hand­held pixel-shift

Amateur Photographer - - Testbench -

Prob­a­bly the Mark II’s most in­trigu­ing fea­ture is its hand­held pixel-shift mode. This is en­abled by set­ting Pixel Shift Res­o­lu­tion func­tion to ‘Im­age Sta­bil­i­sa­tion On’. The cam­era will then take four ex­po­sures and align them to pro­duce a com­pos­ite file.

It’s clear from the out­set that this mode isn’t do­ing the same thing as con­ven­tional pixel-shift. For a start, the cam­era uses the me­chan­i­cal (rather than elec­tronic) shut­ter to shoot the four frames, in no­tice­ably quicker suc­ces­sion. But it then spends an in­or­di­nate amount of time align­ing the ex­po­sures and pro­cess­ing the file, lock­ing you out from tak­ing another pic­ture for 30 sec­onds or more. As with con­ven­tional pixel-shift you end up with a raw file that’s typ­i­cally 170MB, com­pared to 45MB for a sin­gle shot, mean­ing it con­tains the data from all four ex­po­sures. As yet, though, Adobe Cam­era Raw doesn’t un­der­stand how to process it to any­thing more than a con­ven­tional im­age from the first frame.

In hand­held mode, the cam­era clearly isn’t full- colour sam­pling each pixel. In­stead, it’s align­ing and av­er­ag­ing four con­ven­tional im­age files. But be­cause of the slight dif­fer­ences be­tween each hand­held shot, in prin­ci­ple it’s able to ex­tract more de­tail over­all. In prac­tice, the sharp­ness im­prove­ment is much less clear- cut com­pared to the tri­pod-based pixel-shift modes, al­though with favourable sub­jects, it’s def­i­nitely vis­i­ble. But I’m not con­vinced it’s sig­nif­i­cant enough to jus­tify the in­con­ve­nience.

Con­ven­tional pixel-shift, mean­while, be­haves much the same as on pre­vi­ous Pen­tax DSLRs. It gives stun­ning re­sults with static el­e­ments, re­veal­ing vis­i­bly higher de­tail and colour gra­da­tion. How­ever, it’s es­sen­tial to en­gage mo­tion cor­rec­tion when­ever part of the scene may be mov­ing (which in prac­tice means any­thing shot out­doors), as oth­er­wise you’ll get ugly arte­facts that off­set any ad­van­tage of the ex­tra res­o­lu­tion.

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.