[JibbaJab]

You adjust the aperture on the lens itself. The front of the lens should have a ring labeled with the stops (2.8, 4, etc) that turns. Turn it until you get the F-stop you desire.

[savoche]

In addition to what JibbaJab said, make sure you have enabled the use of manual lenses on your camera, as described here: https://www.pentaxforums.com/forums/58-pentax-beginners-corner-q/110658-using...x-dslrs-f.html

[jfca283]

How dumb am i...thank you guys.
Now i will play with the shutter and exposition.
In daylight, what settings do you recommend me for taking portraits with blurred backgrounds?
Again, thank you.
You were very kind.

[JibbaJab]

For now, I would recommend setting your lens to the widest aperture that keeps what you want to be in focus, in focus. For your 50mm lens I'm guessing this should be f/4 or faster. I also suggest pressing the green button (to the right of your shutter button). It uses the in-camera exposure meter to set the shutter speed.

I suggest visiting the Digital Photography School website and reading through the Tips for Beginners (Digital Photography Tips and Tutorials for Beginners - Digital Photography School). Understanding exposure is fundamental to being a photographer. It might be confusing at first, but if you keep at it, one day it will "click" and before you know it your spouse will be yelling at you because you went and splurged on a K-3 because you're now an expert.

[jfca283]

As i said, you all were very kind.
I'll read the links.

[formercanuck]

Just out of curiosity... what 50mm manual lens do you have ?

Many manual lenses have an 'A' setting on the ring. If you're lucky enough to have one of these, then you can set the aperture by the camera, and your 'F--' will read proper.
Eg. I just picked up a Vivitar 28mm f/2.8 manual lens from the SoCal camera bargain show (same goes for my modern Rokinon 85mm f/1.4). It has an 'A' setting on the ring, with a pin. Once set, all I really need to worry about is focus.

[jfca283]

Hi
I bought this
sears 50mm f/1.7 SN215122

[rullrich]

Hi
I bought this
sears 50mm f/1.7 SN215122

Hi Victoria,

that's quite a nice lense according to what people say here on pentaxforums. Did You try to meter with an aperture around f2 and the green button? I found the use of manual lenses is quite easy, although I prefer autofocus since my eyes aren't that accurate anymore. Do You have some pictures to show?

Ralf

[jfca283]

I don't know what does it make the green button.
Besides, my pictures look not quite good.
Out of focus, underexposed and when i tried to adjust the levels i usually burned them.
I really am lost with the manual focus. It's a shame as a newbie to take pictures so awful with a good camera.

[rullrich]

I don't know what does it make the green button.
It's a shame as a newbie to take pictures so awful with a good camera.

No, it isn't, I think that's rather normal.
The concept of the Green Button on Your K-R is rather easy to understand. If You're using an (old) manual lense other then a Pentax A-Lense or lenses with an A (automatic) position on the aperture ring You're camera does not know which aperture is being used, since there are no electronic contacts on Your lense to let the camera know. For this reason pressing the green button in manual mode (M on Your mode dial) stops down the aperture to it's actual value and calculates the correct metering (taking into account shutter speed and iso settings as well). It gives You back a correct metering which You can use. The problem is that when Your subject moves and You turn Your camera into the subjects directions the metering may well be wrong then because Your camera does not update the metering automatically for You. You'd have to press the green button as well. Why not start with more static pictures to get a feeling for it?

Ralf