[Robin127]

As the title suggests I've only recently started taking photos with a DSLR, well, not that recent, I've had my camera about 18 months but have only just started to use it regularly.

I have a K2000 with the 18-55 DAL lens, I already owned a P30T and I had 28mm, 50mm, 28-70mm and 200mm lenses, all manual focus, so it seemed obvious to stay with Pentax.

I have a couple of questions, the 50 and 28-70 both have the "A" setting on the aperture ring, where the 28 and 200 don't, in fact the latter is a lens I've owned since the late 70's and the aperture has to be set manually on it. I know that if I set the ring to "A" on the lenses where this is available that in full manual mode I can adjust the aperture in the camera itself. What I would like to know is there any advantage/disadvantage to using the lenses that don't have the "A" setting on the ring and manually setting the aperture on the lens as one would with a film camera?

The 28mm and 50mm are both Pentax, the 28-70 is a Cosina and the 200 is a Soligor. I have found a problem with the Cosina, it doesn't seem to lock onto the camera body properly, in fact it can be twisted off easily without depressing the lens release button. It seems rather odd as it fits and locks perfectly to my P30T.

One other thing that I noticed this evening that I hadn't come across before, if I did I never paid much attention to it, if I turn the camera upside down and then back upright I can hear/feel something slide up and down in the body. At first I though it was something loose rattling around but it definately is something sliding in one direction and then back again. Is this normal?

TIA for any answers.

[Laurentiu Cristofor]

Lenses without A are plain K-mount style lenses. They can be used on your camera in M mode, using green button for exposure, after changing a setting to allow manual use of aperture ring (check your camera manual). Disadvantage is that you cannot control aperture from the camera and you cannot use them in Av mode stopped down (they only work wide open in Av mode).

What you hear in the body is normal.

Admins - these questions used to be answered in sticky posts - where did those posts go?

[RioRico]

What I would like to know is there any advantage/disadvantage to using the lenses that don't have the "A" setting on the ring and manually setting the aperture on the lens as one would with a film camera?

Con: You have to slow down a little.
Pro: You have to slow down a little!

Let's look at the 3 sorts of MF lenses for Pentax: A-type, M-type, and what I call K-zero type. A-type can be used in any auto-exposure mode; you can let the camera worry about exposures. M-type work either wide-open in any auto mode, or with Green button stop-down metering and exposure in M mode. You gotta THINK about using it. K-zero type, on adapters usually (M42-PK or T2 or cheap macro tubes etc) have no auto-stop-down at all. Such can be used in Av or M (or B or X) with a level of mental involvement somewhere between (or beyond?) A- and M-type usage IMHO.

A gross oversimplification: M-type puts you closer to picture-making; the others, to picture-taking.

The 28mm and 50mm are both Pentax, the 28-70 is a Cosina and the 200 is a Soligor. I have found a problem with the Cosina, it doesn't seem to lock onto the camera body properly, in fact it can be twisted off easily without depressing the lens release button. It seems rather odd as it fits and locks perfectly to my P30T.

I use a cheap PK macro tube set as a test-bed for PK lenses and adapters and mods. Inserting the PK lense into the tube mount section, I can watch the blades and flags and locking pin engage (or not). You might check the Cosina, see if the locking notch is a different diameter than your dSLR's locking pin, and use such a macro tube to see how it actually engages (or not).