Should I get 77mm or 70mm?

We have a 3 lens set of the "limited" lenses coming to photo.net for a review sometime in the near future.

In terms of focal length, there isn't much practical difference between 70mm & 77mm. And from what I hear, they are both nice lenses, so get the one you can find and/or afford.

There is actually a 10mm difference, as the 70mm comes in at 67.6mm tested. As to focal length, try using your zoom experimentally at 70mm for a while, then at 80mm, and you will get a feel for the difference. The longer reach would be better for portrait use without getting in the face of subjects. Also better for candids, as people are less likely to notice their picture is being taken, when the shot is done from a greater distance.

The 70mm, like the 21mm and 40mm Limiteds, is the new DA design for digital cameras, has the new easier-clean coating, and the shift for manual over-ride of AF.

The 77mm still has an aperture ring, and can be used on all Pentax cameras, past and present. It also offers one more stop of speed with an aperture down to f/1.8, which is better for lower light and/or higher shutter speed.

Both are remarkably small considering their focal length and aperture.

Thanks for the information...still a tricky decision! And from what you have said, you think I should add one of those to my 50? And what about wide angle? I was thinking of a manual 28mm 3.5 or 2.8 on Ebay, are either of those any good?

I can only speek to a part of your question. The 77mm f1.8 has nice brokah; no idea of the other (70mm) lens.

In the 28mm world the 28mm f2.8 M and A are very light weight, (49mm filter) but are only reported to be 'decent' lenses. I have the M version, and I'm happy with it because it is so small and light weight and takes very decent photos. The f3.5 is said to be optically a better lens.

Erika -- I have a Kiron 28mm f/2 that is outstanding. They come up on ebay from time to time. It gets the most use on my *istDS, though. I prefer the 35mm 2.8 for my film camera wide-angle.

I have owned and used both the FA77 and DA70. The field of view difference is a bit larger than the nominal focal length differences might indicate (the DA70 seems to test out as slightly shorter than 70mm and the FA77 as slightly longer).

Aside from the obvious weight and size difference (the DA70 is half the length, 2/3 the weight), the DA70 focuses more swiftly and has the Quickshift focusing feature. It's not designed to cover 35mm film format. Rendering-wise, they are about as identical as two lenses can be that are of different focal lengths. The DA70 might have *marginally* less CA but by such a small fraction it's inconsequential. The FA77 has an aperture ring so can work on an old-style K-mount bellows or extension tube where the DA70 requires a KA- mount bellows or extension tube.

Both are excellent lenses. Pick the one that suits your fancy and enjoy it. I prefer the wider field of view of the DA70 and its QuickShift focusing feature, also its smaller slze.

Godfrey

As others like Godfrey have pointed out, both are good lenses. The DA70 "pancake" is smaller and I find that appealing as I generally prefer to travel light. Here are links to two sets of photos taken with the DA70, if you want to see a range of sample photos.

San Clemente Car Show

Amsterdam

Ned

I agree with Donnie: the Kiron 28mm f2.0 seems to perform as good as the Pentax A 28mm f2.8. OTOH I don't like using plain k-mount lenses without A setting on DSLRs. I also have trouble setting focus manually, especially in low light situations (I tried shooting concerts with a Exakta 24mm f2.8 lens), so I can only suggest to get some AF wide for indoors, since wides are harder to focus on SLRS in general and the DSLR screens are especially nasty. The Sigma 24mm f1.8 is a huge chunk of glass and plastic, but if you don't mind that, something to start with and maybe add a 14mm f2.8 Pentax later to a 2nd or 3rd body. Old Sigma 14mm f3.5 A lenses don't perform really well, so safing to get the Pentax is a good idea.

The Pentax 28mm f3.5 has a good reputation, but to me it seems more like a compact hiking lens than a indoor available light performer and it isn't really wide, so the 21mm limited lens might be a better choice, if size matters a lot.

Jochen -- I agree about the focusing. I got a split-image/microprism screen on ebay that works great. I just wonder why Pentax doesn't offer them --it makes manual focus a snap!