▁the ▁N ikon ▁IX ▁series ▁of ▁l enses ▁were ▁not ▁compatible ▁with ▁the ▁N ikon ▁ 3 5   mm ▁SL R , ▁l enses ▁for ▁the ▁N ikon ▁ 3 5   mm ▁SL R ▁were ▁compatible ▁with ▁the ▁N ikon ▁Pr one a . ▁Using ▁existing ▁l enses ▁meant ▁that ▁the ▁field ▁of ▁view ▁was ▁reduced ▁by ▁around ▁ 1 . 6 × , ▁but ▁had ▁the ▁advantage ▁of ▁a ▁larger ▁l ens ▁selection . ▁Creating ▁a ▁new ▁l ens ▁system ▁on ▁the ▁other ▁hand ▁gave ▁the ▁possibility ▁of ▁creating ▁smaller ▁and ▁l ighter ▁l enses ▁as ▁they ▁had ▁a ▁smaller ▁image ▁circle ▁to ▁cover . ▁A PS ▁SL R ▁cam eras ▁were ▁too ▁expensive ▁for ▁the ▁high - end ▁amateur ▁market ▁when ▁they ▁first ▁appeared , ▁and ▁professional ▁photograph ers ▁stuck ▁with ▁ 3 5   mm ▁cam eras , ▁which ▁offered ▁greater ▁image ▁quality ▁and ▁resolution . ▁ ▁Pres ently ▁the ▁terms ▁A PS - C ▁and ▁A PS - H ▁are ▁most ▁often ▁used ▁in ▁reference ▁to ▁various ▁makes ▁of ▁digital ▁SL R ▁that ▁contain ▁imag ing ▁sens ors ▁that ▁are ▁( very ) ▁roughly ▁equivalent ▁to ▁their ▁respective ▁film ▁dimensions ▁given ▁above ▁( see ▁C rop ▁factor ). ▁Con current ly ▁to ▁their ▁A PS ▁SL R ▁film ▁cam eras , ▁some ▁manufact ur ers ▁released ▁l enses ▁intended ▁for ▁use ▁on ▁A PS ▁film ▁cam eras ▁- ▁such ▁as ▁the ▁Can on ▁EF ▁ 2 2 - 5 5 mm ▁- ▁which ▁had ▁a ▁wider ▁field