pentax lenses compatible with EOS bodies?

[bighatphotography]

if I want to shoot a roll of film, I head for my pentax k1000. So I have a few pentax K mount lenses, that I thought about picking up an adapter to use them with my T2i and 70D. But I heard somewhere that the aperature lever on some K mount lenses can hit the mirror on canon bodies which would be bad....

So anyone have any horror stories about this? or is it just a myth or very few lenses?

 

[bighatphotography]

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