Hello, I am a total newcomer to rangfinder and have two basic questions regarding my new Bessa R4a and Screw mount Nokton 50 1.5mm installation and viewfinder focusing: 1) I have first carefully mounted the proper adapter ring. Then screwed my Nokton 50 1.5 as far as it will go. However The white dot on the lens is about 2 or 3 degrees short of reaching vertical with respect to the camera body - it simply won"t turn further. Is this normal? How tight is one supposed to crank a screw mount lens? 2) This admitedly is a very splitting hairs perfectionism question: - but focusing of same lens, when viewfinder images are aligned horizontally, the image overlap is ever so very slightly off vertically in the viewfinder and I do mean slightly. Is this normal also? BTW, I ordered this camera with the 35 Biogon Zeiss F2 also. I am amazed at how tiny that $900 lens is. Also, the build quality of the Voigtlander pieces is higher than I thought they would be. Aside from the quieter shutter of the M Leicas, and near zero distortion of a few Leica and zeiss wide angle lensesI can't see wanting more. Thanks in advance for any help answering these two questions.