2nd chance w/ Pentax?

I bought a K100D last year just for the 21mm pancake lens. However, the focus

was so appalling (as compared to my Nikon D50--nothing personal) that I chucked

the body after a month but still kept the lens. I'm now debating whether to

chuck the lens as well or give Pentax another try. My preference is for small,

so the discontinued DL or DS2 are looking appealing. Can anyone tell me if the

atrocious focus issue was just a fluke should one learn to settle for less when

it comes to Pentax & auto-focus. Thanks.

Chuck the lens, just tell me when and where you are chucking it so I can catch it...

 

If the focus of the K100 bugged you, it was probably because it has a mirror VF

instead of a prism. I can't tell you for sure which of the *ist models (if any) had a prism

other than the original *ist-D.

What was your focus issue? Are you talking about manual focus?

 

As a previous owner of a D70 with AF-s lens, I found the AF of K100D with kit zoom absolutely OK !

If you could just explain what do you mean by "focus" a bit more...

I came to my K10D from a Nikon F100 which had very accurate autofocus. I thought the K10D hunted a bit more but was decent. However, i am upgrading to a K20D partly because not only is it faster and more accurate, it allows you to dial in compensation if it has a front or back focus problem with any given lens. And it remembers this compensation and applies it every time that lens is remounted on the body! If you get back into Pentax, you might want to spend a bit more -theK20 D has many such features as yet undreamt of in Nicanon land.

Was your focus issue at close, mid, or more distant point? I have the same combo, but have not noticed issues so far.

Ah, but i forget, you said small. the K20D is only kinda medium.

I have *ist DS2 and the DA21 and while it works OK for me I wouldn't expect it to be much different than K100D except for the bigger/brighter viewfinder. AF speed can also be battery-power sensitive. The K10D seems to have noticeably more consistently snappy autofocus, probably in part due to its more powerful li-ion battery. Fresh batteries (or perhaps Lithium) might help somewhat in the AA-powered models.

 

I think we would need to know more about your specific complaints to compare your expecations against our collective Pentax AF experience.

I'm pretty sure that the ist DS was the last glass pentaprism on the entry level bodies. The DS2, DL, K110, K100 are all pentamirrors and not as bright and easy to focus manually as the glass pentaprisms of the D, DS, K10, K20...

By focus, I mean auto-focus. I found it to be consistently inconsistent--maddeningly so. Pics were out-of-focus far out of proportion to what I would expect, and what I had become used to using a modest D50 w/ equivalent lens. I very frequently had to switch to manual focus in hopes of salvaging what was left of the moment. This occurred more frequently in low light, obviously. But there were numerous occasions where I would be outside on an overcast day and it would get it wrong.

 

I mostly do spontaneous-candid-street, so most of my subjects were between a meter and three. Most situations did not seem especially challenging focus-wise. I'm curious to know if I'm just unlucky or if this is as good as it gets w/ this combination. Mind you, I'm not knocking Pentax. I commend them for innovating w/ compact primes, which is why I bought one. I have no particular brand loyalty, so long as Brand X can live up to my rather modest expectations.

Two points... firstly, if you let the camera select the autofocus point automatically then you may not be satisfied with the focus point that it chooses (ie. it may get it 'wrong'). Most of us here set the focus point to center because that way we have complete control... just focus and recompose.

 

If the problem you are having is not do with the focus point selected, but rather mis-focusing at the chosen point, then this may actually be a front/back focus problem with the lens rather than the camera body (though it could be the body). I don't own the 21mm ltd but I have heard quite a few people on these and other forums having FF/BF issues. Fortunately I believe this can be fixed in most cases by using a hidden setting in k100d / k10d firmware. As mentioned above, the k20d provides the facility to adjust focus for all your lenses and remembers which is which.

Can anyone else confirm that there have been quite a few focus issues reported with the 21mm ltd? My above post should be read with the disclaimer that I am not a reliable source of information on this subject. I haven't checked back through forum posts, but it is something you may like to follow up yourself.

The DS2 has the pentaprism viewfinder, pretty much indistinguishable from the K10D. Del is right about the DL, DL2, and KxxxD.

The *ist-D, which I also have, and DS have the same pentaprism VF as the K10D and K20D. Yes it is somewhat better, the degree of which is an individual matter. Thiis VF is rated excellent, but the K100D VF is still rated very good, and above its competition, including the Nikon D50.

 

Ashley is right- in some scenes a multi sensor AF can pretty often lock onto the wrong area. Center-only is highly selective, and the safest choice. Another factor acting with that factor is in lower light with wide open aperture and at closer disdance, DOF becomes shallower, so any focus lock on an off area will have more undesirable consequences.

 

I have found the AF with the K100D to be very satisfactory. Now, the moderate telephoto length of the 77mm Limited, along with an aperture of say around f/2.8 taking a shot at close distance would be with very shallow DOF, making focus very critical. Here are a couple such quick shots taken last summer using the K100D with normal AF. As you can see, it did a fine job with choosing focus point, hand held, despite very limited DOF. And this has been typical.<div></div>

I thought it would take as attachment-

I don't know- I have used this image before....

ok, good. Now hear's another-<div></div>

Arond, <p>

My K10D had a "terrible" back focus problem. My K100D had a minute amount of it! The focus problem was for "all the lenses" I attached to the body; Pentax or Sigma did not matter. I have adjusted both using the procedures described here and elsewhere. The K10D needed a big number to come to senses, the K100D only a small one. Now they both work nicely.<p> You notice the problem with apertures resulting in shallow DOF. Apertures 8 and narrower makes the detection of the fault difficult due to increased DOF.<p>

I suggest you first check the situation with other lenses and than decide if the issue is with the lens or with the body. It is easier to make the correction on the body since you can DIY. <p>

There has been some discussion about this (pentax + back focus) recently here at PN.