How do I get manual lenses to work better?

Okay, so I kinda sorta got this vintage Pentax K-mount 50mm prime f1.4 to sorta work on the Pentax K30.

A few things still don't work though.

1. Cannot adjust aperture at all with the manual ring. It looks like it's locked somehow. I cannot figure out the menu settings to change this.

2. I'd like to set it so that one dial controls shutter speed and the other controls ISO (since the aperture ring should control aperture, though maybe it can be controlled from the camera? I wouldn't mind)

But it ends up being neither. For some reason it will default to 1/125 and auto ISO. Or, I can set iso in the menu to like 200 and adjust shutter, but can't use the more useful auto-ISO + adjust shutter via dial.

BTW, opinions on this lens? It's 50mm SMC Pentax F1.4. Wonder if it's a keeper.

Maybe you should first make sure the lens is actually working?

unplugged from the camera, the aperture ring should turn easily a block a little on each mark. The focus ring should turn easily without noise.

Once this is ok, you can go through settings on the camera.

(and, yes, if the lens is working, that's a keeper)

1) What is your camera model? There is always an option to activate manual lenses

2) If it is a SMC M lens, you won't be able to control aperture. In M mode you should be able to modify ISO and shutter speed. Green button will meter the light and adjust shutter speed for you. (Maybe you should take a look at the manual)

There is a menu setting to allow the use of manual aperture rings, your camera manual should show this.

Assuming that you can actually turn the aperture ring then I guess your problem is that the camera does not show the aperture, just -- on the display? That is OK as there is no way for the body to read the aperture.

You can only use M mode if you want to shoot at anything other than wide open. Set the ISO you want, select the aperture then hit the green button to set the shutter speed.

If you try to use Auto ISO the camera will default to TAv and only shoot wide open.

With the optical preview function you can check if the diaphragm closes as you want it to. (take M-setting, enable use of aperture ring, set ISO yourself, etc). Set aperture on lens, Green button sets the shutterspeed, to be changed manually by the turning wheels. The lens migt be defective.

As suggested, your lens might be faulty.

I use a Pentax M 135/f2.5 and the M 50/f1.7 on my G1 body (with an adaptor). Set on P I stop the lens down and the camera adjusts the shutter speed. Auto does not work at all.

Works fine.

Here you'll find an excellent explanation:


The 50 mm f 1:1.4 is excellent. You'll find maximum sharpness and nice soft backgrounds between 2.8 and 5.6.

Since the glass is rather exposed it is sensitive to flare so you're advised to use a lens hood. I like a 49 mm threaded rubber hood on my FA50mm 1.4.

Regards,

Karet