F-Stop??

[Stacey]

I have a Pentax K100D. Came with a 18-50mm kit lens and I have some others that are for my DSLR (one Sigma and one Tamron). When I have my kit lens on my camera I can manually change the F-Stop, when I look through the viewfinder I can see the F-Stop and change it as well as the exposure(?)(the -.50/0/+.50). However when I have my other lenses on, I lose the capability to see the F-Stop or change it...It doesn't matter if the camera is in manual mode or TV or AV....I hope I'm asking this right? I don't know if this is a big deal or anything like that but I'm confused about why this does this? If anyone can shed any light on this, I'd appreciate it! Thanks so much!
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[KhronoS]

Try cleaning the contacts of the lens and of the camera as well, the place where youyr lens and camera connect. If still doesn't work, go to the store you bought it and tell them about it, and they will fix it is it's still in guarantee.

Good luck

 

[deudeu]

Do your other lenses have aperture rings. If they do, you need to make sure that they are set to A.