At f13 and smaller you're hitting the diffraction limits of the sensor/lens combo and giving up quality. Unless DoF is an issue, there's no good reason to stop down past f11 on 1.5x crop digital. The 16-50 will outperform the 24-50 at apertures where diffraction limits are not an issue.
-Adam On 3/11/08, J. C. O'Connell <[EMAIL PROTECTED]> wrote: > that's good to know but are you talking much sharper > at F11-F22? I cant see how there would be a big > difference in that range, the A24-50 is really good > in that range on digital size sensor. The A24-50 is > also much smaller and lighter tha the 16-50 > isnt it? That matters to me when the camera is hanging > on my neck for long periods... > > jco > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of DagT > Sent: Tuesday, March 11, 2008 12:21 PM > To: Pentax-Discuss Mail List > Subject: Re: GREAT "general purpose" Zoom for the Pentax DSLRS? > > > I tried the A version on K10D this summer. I´ve had it since the mid > 80s and it has been great with film, but compared to my primes in that > range it wasn´t not sharp enough for my use on K10D. My DA*16-50 is > much better. > > DagT > > Den 11. mars. 2008 kl. 04.22 skrev J. C. O'Connell: > > > Did you have the A version or the F version? I have had both and my A > > version is better than the F which I sold. Dont forget, I am talking > > about > > near > > range > > usage and at small fstops like 11-22 because the flash is powerful > > enough > > to allow those stops even at iso 200. I have no idea if its any good > > at > > infinity > > or anywhere near wide open, but if used like I am using it, its damn > > nice, > > not too expensive, and good build quality too.( I ususally dont like > > most > > A lenses in terms of build, but this one aint bad.) > > jco > > > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf > > Of Adam > > Maas > > Sent: Monday, March 10, 2008 10:56 PM > > To: Pentax-Discuss Mail List > > Subject: Re: GREAT "general purpose" Zoom for the Pentax DSLRS? > > > > > > Tried one out at one point. It was alright, but not any better than > > the > > 18-55 DA in its range, larger, heavier, harder to manual focus due > > to lack > > of contrast wide open at 24mm. Wasn't much impressed with it on > > digital. Of > > course, I may have had a bad sample. > > > > -Adam > > > > On 3/10/08, Walter Hamler <[EMAIL PROTECTED]> wrote: > >> Never seen that particular lens. I had a 35~105 years ago that I > >> really liked except it was pretty heavy. My biggest problem is at my > >> age the AF is almost a requirement anymore :-) > >> > >> Walt > >> > >> > >> On 3/10/08, J. C. O'Connell <[EMAIL PROTECTED]> wrote: > >>> I have been using for about a month now the SMC PENTAX-A 24-50/4.0 > >>> Zoom almost exclusively ( mostly product photos for ebay on > > >> tabletop ) on my *istDS DSLR. Its a two ring zoom so you never > get > >> any annoying "zoom creep" and it holds focus perfectly > when > >> zooming. The F4 speed is a little slow but the lens is so > > >> contrasty > >> that its easy to focus at 50mm ( I use a split image > screen - > >> third > >> party model - in my *istDS ). Anyway, after you > figure in the 1.5X > >> lens factor you are left with a 35mm SLR > equiv of 36mm to 75mm > >> which is a very versatile "super normal" > lens. This model is > >> extremely contrasty, great color saturation, > and freedom from > >> flaring. It works beautifully for tabletop > product photography. I > >> have never needed wider or longer, as it > has a pretty decent > >> magnification at 50mm and min focus. The constant > aperture (F4 > >> thru > >> the zoom range) is great when using manual full > power flash like I > >> like to do. > > >>> Anyway, if you do a lot of ebay or similar product photography for > >>> web, > >>> I recommend this lens very highly. Much more versitile than a > >>> prime or macro 50mm with the 24m capability. > >>> > >>> I must add I have never used the stock 18-55mm that was sold > >>> with the camera, but I doubt it can match this lens, let alone > >>> beat it. Maybe it can? Anyone ever compared the two in the 24-50mm > >>> range? > >>> > >>> jco > >>> > >>> > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
