If the mirror on your TL Electro hangs up on the lens, then yes, there is slippage, as they were designed to use the Yashinon DX lenses, which protrude into the body more than any other lenses. I haven't had that problem on any M42 Yashica bodies, but have had it on a Contax 137MT and a Yashica FX2. If a warm sunny day is not available, gentle use of a blow dryer will work.