[coliver80]

Well Ive never owned a prime lens(let alone an old one). so when I got my K3 I decided to jump on the band wagon and try them. Went to local flea market and picked up a very nice PZ30 with battery charger, strap, 50mm-A 1.4 with original cap for $50. Also got a rough but working A3000 with a 50mm-A 2.0. Both lens are clean no fungus. The 1.4 works nicely.. but the 2.0 focus ring turns from stop to stop but dosen't focus(no lens movement either). There is slight resistance about halfway between stop.. can this be easily fixed or should I just use it for display?? Also I've noticed that while using the 1.4 I'm getting mush sharper images using live view with focus peeking as compared to waiting for the camera to beep in manual phase focus... is this normal or am I doing something wrong?? Thanks ahead of time for any anyput!!

[jatrax]

If you have the A 50mm f/1.4 just put the f/2 on display. The f/1.4 is superior in all respects. And it works.

Focusing a manual f/1.4 lens on a digital camera is not easy. Using liveview is certainly going to be easier. You can do manual focus with the viewfinder but it takes a lot of practice. Make sure your diopter is set properly.

The focus confirmation is really for f/4 or slower lenses, it is a range not too precise and there is enough slop in it that at f/1.4 you are going to miss a lot. Liveview in this case is more accurate. Stop the lens down to f/4 and see the difference.

[wombat2go]

Stop the lens down to f/4 and see the difference.

Jatrax,
That lens can not be stopped down when focussing on a Pentax dslr or slr

[othar]

Jatrax, That lens can not be stopped down when focussing on a Pentax dslr or slr

It should be possible by using the lens manually with the aperture ring and the preview function

edit: I was mistaken it works fine with the A setting too, just set the aperture you want and use the preview funcition. aperture is closed as long you push the button with my K3.

Edit: The cameras I have here, the lens stops down for a short time when the button is pressed, not long enough for viewing.

When I use the green button to set my shutter speed automatically it shows that behavior

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Last edited by othar; 12-06-2014 at 03:41 PM.

[wombat2go]

It should be possible by using the lens manually with the aperture ring

Othar,
No, the camera holds the lens fully open all the time until the shutter button is pressed. Then it stops down to the value selected ( on the ring if in manua) . Then it opens fully again after the exposure.

Edit: The cameras I have here, the lens stops down for a short time when the button is pressed, not long enough for viewing.
I don't know if the later Pentax cameras allow a continuous stopped down preview?

[jatrax]

That lens can not be stopped down when focussing on a Pentax dslr or slr

Why not? Use the optical preview.....

But I meant if you shoot at f/4 it will mask the imprecision of the focus beep by increasing the DOF in the resultant image, so you will get more keepers. But, you are correct it will not change the view in the viewfinder (unless you use optical preview)

[sorted78]

but the 2.0 focus ring turns from stop to stop but dosen't focus(no lens movement either). There is slight resistance about halfway between stop.. can this be easily fixed or should I just use it for display??

I've had a similar issue with an A50/2.0. The focus ring is clamped to the helicoid mechanism that moves the optics involved in focussing by 3 screws. This allows the lens to be calibrated so that the distance scale is accurate.

It sounds like your focus ring is loose. It might just have come lose, but it might also be because there's a problem with the lens. In the case of mine, it had been dropped at some point and bent the focussing mechanism. There was no obvious physical damage (presumably it had a lens cap/hood on), but the focus mechanism was jammed solid.

In any case, as others have said, the 50/1.4 is a much better lens, so you have nothing to lose by trying to fix it if you're interested. There are instructions on how to strip down an M50/2 here at the link below. Mechanically it's very similar to the A50/2. Have fun...

Pentax 50mm repair 1

[wombat2go]

aperture is closed as long you push the button with my K3.

That is a useful feature, I did not know it was available on K3.
Is it on any of the other models?
It used to be called DOF preview on the film slrs , the Pentax MX for example has it.

[jatrax]

That is a useful feature, I did not know it was available on K3. Is it on any of the other models? It used to be called DOF preview on the film slrs , the Pentax MX for example has it.

K-5 has it as well, not sure about other models. It is on the on/off switch, just push it past 'on'. It is marked with an aperture symbol

I think you can map other buttons to that as well but I've never seen the need

[othar]

That is a useful feature, I did not know it was available on K3. Is it on any of the other models? It used to be called DOF preview on the film slrs , the Pentax MX for example has it.

on the K3, Pentax *ist D, K10D, K20D, K-7, K5, K5II and the K5IIs there is a 3rd positon on the on/off switch for the optical preview, on the other digital cameras the DOF preview can be assigned to the RAW/fx button

[wombat2go]

on the K3, Pentax *ist D, K10D, K20D, K-7, K5, K5II and the K5IIs there is a 3rd positon on the on/off switch for the optical preview, on the other digital cameras the DOF preview can be assigned to the RAW/fx button

Ha, never knew that.
On my ist-ds, the focus confirmation does not work in preview, but preview is still useful
On the K-01, if I assign preview I lose ether green button exposure, or focus peaking, both are essential for the K-01. ( I am not 100% sure of this)

Thanks!

[Just1MoreDave]

I've had a similar issue with an A50/2.0. The focus ring is clamped to the helicoid mechanism that moves the optics involved in focussing by 3 screws. This allows the lens to be calibrated so that the distance scale is accurate.

It sounds like your focus ring is loose. It might just have come lose, but it might also be because there's a problem with the lens. In the case of mine, it had been dropped at some point and bent the focussing mechanism. There was no obvious physical damage (presumably it had a lens cap/hood on), but the focus mechanism was jammed solid.

I think what happened is the sudden impact, jam, then someone attempted to force the focus ring. Instead the three screws were no match for them, so now it turns freely. The 50/2 lenses are prone to this jam. The website instructions are correct but suggest a lot of disassembly which is extra work. You can fix the jam by snapping the aluminum ring (that does the actual focusing) back into place. Just unscrew the black beveled ring around the front element off, or pry it off if the filter threads are too bent to unscrew. It's plastic so it'll bend a little. Then unscrew the screws holding on the filter ring, and the screws holding on the focus ring. The aluminum ring should be parallel to the mount. Jammed rings are not parallel. Look for the low end and pry until it pops.

[coliver80]

Thanks for all the info guys! Followed the link above and got it fixed! The Barrel was jammed.. popped it in place with a flat head. Then spent the next hour trying to get focus stops calibrated.. after that had to dismantel again to fix pin that controls the A setting in aperature(I like to have the f-stop info in my exif). Works perfectly but I do agree.. I think Im going to get alot more use out of the 1.4. I was going to get the new 50mm 1.8 DA but might save my money for something else now that I have a couple 50s, unless the DA is that much better???

[jatrax]

I was going to get the new 50mm 1.8 DA but might save my money for something else now that I have a couple 50s, unless the DA is that much better???

It will not be significantly better. Possibly a little since it has newer coatings. The only reason (IMHO) to buy it over what you have is if you want the auto-focus. If so then it is a great little lens.

[boriscleto]

If you have the A 50/1.4 there is no need for the DA.