Pentax 67 Close-Up Lenses on 645 FA 150/2.8

[rayn]

I'm trying to find a high quality close up diopter for my Pentax 645 FA

150/2.8 lens. This lens has a 67mm filter thread and there are few

diopters to be found at this size (Canon's closest is 72mm, Nikon's

closest is 62mm). I know Pentax makes some 67mm close-up diopters for

their 67 system, but have heard very little about them. B&H sells

three powers at about $100 each. Will they work with my 645 lens? Are

they high quality, two element diopters? (B+W, Hoya, etc. are cheap one

element). I'd rather not use step-up or step-down rings. Thanks.

[art_haykin]

Any close-up diopter lens you can adapt to your lens will work if it's big enough to cover without vignetting. Single diopter lenses are NOT necessarily low quality, and if you understood how they worked, you'd better understand this. And just what is wrong with step-up or down rings? I used them for yearswith great results. The reason the larger ones are so expensive is that the volume of sales is comparatively low.

[rayn]

I don't want to use step-up rings because I'd have to buy and carry a second set of 81A and Polarizer filters to fit the new close-up lens. My lens hood also wouldn't fit over the 72mm step up, and stepping down can vignette. I didn't mean to insult the single element lens users out there. I only ask this question because I've never heard of the Pentax one and I don't want any "surprises" after paying $100 for it.

[art_haykin]

It seems to me that any new, brand name lens, filter, or anything, that didn't perform as represented could be returned to the dealer. If your dealer is uncooperative, find a new one.