Originally posted by mikecnorthwest I’m using a Tamron 100-300 on my K-70. I’ve noticed several times after taking a shot that the next exposure is underexposed. Adjusting the aperture has little effect. If I take the shot, most the time, but not always, the exposure will correct back. When it doesn’t, I have to turn the camera off, take the lens off/on, and turn the camera back on. I have not noticed this with my other lenses and I don’t think this sounds like the aperture block failure. Any thoughts?
You may want to check out this thread!
K-70 Underexposed Photo Reports - PentaxForums.com