Unable to focus to infinity? (Heinz Kilfitt lens)

<p>I have an old Heinz Kilfitt mounted on my Nikon D300. It's a great lens as long as I stop it down, but it seems that I can't focus to infinity. When I took the photo below, I had the lens focus mark on infinity. The "High Voltage" sign is in focus (~100m away) while the bus stop / kids are out of focus (~200m away). Is there anything wrong with my lens or am I doing something wrong? I don't use manual focus very often.</p><div></div>

<p>Hi William. Inability to focus at infinity suggests that the lens isn't as close to the sensor plane as it needs to be. Are you using a third-party adaptor, or does the lens have an F-mount bayonet? (I know little about the Heinz Kilfitt lenses, although they look interesting.)<br />

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If you're using an adaptor, I suspect it's slightly too thick - you might have more luck with another one. If you're not, the lens would need adjusting. I assume, of course, you're hitting the end of the focus range and you weren't claiming "infinity" correponds to a mark on the lens, or where the camera's autofocus module tells you it is? (If so, try live view.)<br />

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Good luck, but it sounds to me as though you've got some work in your future. In the meantime, I can only suggest stopping down and hoping the hyperfocal distance is enough, but that may not be why you bought an f/5.6 lens...</p>

<p>Thanks Andrew. The lens does have a 3rd party adapter that might be the cause of the problem.</p>

<p>You have too much extension in your rig and this needs to be reduced to enable you to focus at infinity. A Canon EOS would probably be more accomodating as it starts with a shorter sensor to lens mount distance. EOS is 44mm, Nikon Bayonet is 46.5mm ,,, that gives you an idea of how much out you currently are.</p>

<p>Hi William. Sorry not to have better news. I believe there's a known problem that some third-party adaptors for different formats have slightly lax quality control when it comes to thickness - some lenses focus past infinity, in which case it wouldn't matter so much, but it sounds as though you've been unlucky. Maybe try to source another adaptor, with a return policy? I assume there wouldn't be an adaptor if the flange distance weren't compatible with the F-mount, so it shouldn't be necessary to resort to Canon - unless there's some small print on your adaptor that says something about infinity focus. Good luck.</p>

<p>It could be my monitor, but the electric pole in the foreground seems to be in perfect focus, while the kids who are parallel to the pole are blurred ?</p>

<p>I'm not sure about lax quality control but rather the makers expect the customer to know about extension and the adaptor would be perfectly AOK if used for closer photography than infinity, such as when one buys non-optical adaptors for FD lens on EOS camera. A more expensive adaptor might well incorporate a lens to correct for the increased extension, although I gather these do not always result in the best image quality ... no personal experience.<br>

I purchased the cheapest M42-EOS adaptors for my old lens and they work AOK but I bought Canon becuase I was aware of the problem and the simple solution.</p>

<p>As an aside, if that pole is 100 meters away I cannot believe that bustop and people are 200m away. The perspective doesn't seem to be that way to me, tho I may be misreading the compressed scene.<br>

As Harry implied, is that left side of the image 'fuzzy' because of lens alignment issues/or similar rather than the 'distance' issue being discussed?</p>

<p>Jim M.</p>

<p>I'm flying to Japan pretty soon and my lens is already packed. Once I land I'll take some more test pics and inspect the mount. I bought the lens used (understating the obvious :P) but it already came with the non-optical F-mount adapter.</p>

<p>@Harry: Yes the high voltage is focused, but the kids are not parallel due to image compression from using a long lens.</p>

<p>@Jim: My guesses are way off. I remeasured using Google satellite maps. For reference, I've attached a second pic below from a different lens and I've circled the two points of reference. The bus stop is ~220m away. The high voltage pole is ~130m away.</p><div></div>

<p>William - I'll be interested to know what your Heinz Kilfitt's native mount is. A bit of googling shows up one in an Arri Standard mount (for cine cameras), and it certainly appears that this should be adaptable to Nikon without needing any glass - in other words, the adaptor isn't thin enough, but there's no reason it shouldn't be. I'm assuming, of course, that everything is mated together properly - if your lens isn't properly on the adaptor, of it the adaptor isn't locked onto the Camera, or if something's been thumped so that it's not the shape it's supposed to be, you could see this problem. According to Wikipedia, if you <i>have</i> got an Arri standard mount lens, the mount is a bit under-engineered, so something may have happened to it. I'd check that there's nothing trapped in it, that everything seats together properly, and that everything's solid - if it flexes under its own weight (you aren't trying to support a 400mm lens from the camera, are you? I assume you've got both the lens and camera supported, at least by hand) that might also add some effective distance between lens and image plane that you don't want. I'm guessing, though, never having seen one of these lenses (and not being an expert!)<br />

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Harry - you saw that as kids being parallel to the pole? How big are the power lines in your neighbourhood? :-)</p>

<p>Maybe the previous owner didn't know about Photo.net to help him sort out his problem :-)</p>

<p>I have been doing some lens repairs recently, one of them, a Vivitar 135mm, I had to actually set the infinity on it as I had removed the core from the helical section that is used for focusing. It might be fairly easy to reset the focus on it. I have not been able to find anything on Google (short search) on the construction of it. If it is like many lenses that I have seen or personally been into, you might be able to get access to the focus settings by removing the front name plate. I don't suppose you have a picture of the lens? I also noticed that you have not listed the specs of the lens, like what size it is and what its ƒ-stop is.</p>