Jump to content

Nikon D7100 With old Ai lens


marcantel

Recommended Posts

<p>I was so excited to learn my new D 7100 accepted my old Nikon glass 55mm1.2,105mm 2.8 and 3rd party 80-200 2.8 Tokina. My big Question is does anyone know if my old Pentax 500mm 4.5 Screw mount w/a m42 sm to bayonet adapter to nikon would work? I 'd like to know this before I buy a nikon adapter. Thanks Any info appreicated</p>
Link to comment
Share on other sites

<p>Indeed, my mistake. I always forget those!</p>

<p>Non-AI lenses must be converted before they can be used on <em><strong>any</strong></em> digital body (except the D40, D40X, D60, D3000, D3100, D5000 and D5100).....and you've got a D7100.<br>

<br>

I guess any adapter will be AI or later....There are plenty of pics on line that show the difference....such as..<br>

<br>

<a href="http://www.aiconversions.com/compatibilitytable.htm">http://www.aiconversions.com/compatibilitytable.htm</a></p>

Link to comment
Share on other sites

<p>The register (sensor/film to mount distance) for M42 is 45.46mm. The Nikon mount is 46.5mm. Considering that the adapter itself has to be a few millimeters thick itself, using your M42 screwmount lenses has the problem of placing your lens too far away from the sensor, akin to using extension tubes. This means that your lens will lose infinity focus, and will likely focus no further than 12-15 ft away (just a guess, haven't looked it up or done the math for the exact numbers). You could alleviate this by buying an adapter that uses corrective optics that restores infinity focus, but then you are degrading the image with iffy lens elements between the lens and the sensor. The existing adapters with corrective optics greatly degrade the image. The Nikon F mount is one of the longer ones, so adapting lenses to our cameras isn't a realistic proposition. Plus, you now have to stop down the lens manually, making it quite a hassle unless you're doing tripod-mounted work.</p>

<p>Theoretically C Watson, you COULD adapt a non-Ai lens, but you would risk breaking the aperture tab on the lens mount. This old thread explains it:<br>

<a href="/nikon-camera-forum/00bLri?start=0">http://www.photo.net/nikon-camera-forum/00bLri?start=0</a></p>

Link to comment
Share on other sites

<blockquote>

<p>AFAIK <em>any</em> lens with a Nikon F mount, either directly or via an adapter, will work on your D7100.</p>

</blockquote>

<p>Actually, there are a few more exceptions to that besides non-AI lenses. For example, in the early days, there were some old fisheye and wide angle lenses that would protude into the mirror box. Those lenses require a true mirror lock up to use, typically with an external viewfinder that you mount onto the hot shoe.</p>

<p>There are also some modern PC-E tilt-shift lenses that are blocked by the viewfinder overhang on the smaller DX DSLRs. I haven't tried my 24mm/f3.5 PC-E on the D7100, but on the very similar D7000, it took me 10 minutes to figure out how to mount that lens to begin with. And once mounted, I could not shift that lens because it was blocked. I suppse one can argue that combo is "useable," but you would be using that term very loosely.</p>

Link to comment
Share on other sites

<blockquote>

<p>"My big Question is does anyone know if my old Pentax 500mm 4.5 Screw mount w/a m42 sm to bayonet adapter to nikon would work?"</p>

</blockquote>

<p>- Sorry, no it won't work. At least it won't be able to focus to infinity. As has already been said, the register (distance from lens mount to sensor) for Pentax/Praktica M42 lenses is shorter than that of Nikon's cameras. Therefore the lens will sit too far away from the focal plane to focus at infinity. OK for macro work, but forget landscapes.<br /> You <em>can</em> get an <a href="http://www.play.com/Electronics/Electronics/4-/18751114/693182454/Kiwifotos-Lens-Mount-Adapter-Allows-M42-Screw-Mount-Lenses-to-be-used-on-Nikon-D-SLR-s-with-Infinity-Focus/ListingDetails.html?_%24ja=tsid:13315%7Ccat:18751114%7Cprd:18751114&ef_id=UUDLywAAAYOs7oDT:20130704173150:s">adapter with a negative lens element in it</a>, but this will greatly reduce image quality and pretty much defeats the object of using other marque lenses on Nikon bodies. Anything advertised as offering infinity focus will have a cheap single glass lens in it and IMHO should be avoided.</p>

<p>If you want a DSLR that takes the greatest range of other-make lenses, then you need a Canon digital Eos body. The short register of a Canon makes it ideal for taking M42, Nikon or almost any other make of lens. Beware though; some M42 lenses protrude into the Canon body far enough to collide with the mirror!</p>

Link to comment
Share on other sites

<p>I bought an adapter with an element in it to use an old lens that an old relative gave me. It was usable enough for me to tell the old relative that I appreciated his gift and that I had actually used the lens. It did work. But in practical terms, no.</p>
Link to comment
Share on other sites

<blockquote>

<p>"<em>AFAIK any lens with a Nikon F mount, either directly or via an adapter, will work on your D7100</em>."<br>

As long as it's not a NAI F mount.</p>

</blockquote>

<p>They say that about the D3200 too but I have no problems using pre AI lenses on a D3200.</p>

Link to comment
Share on other sites

<blockquote>

<p><em>"They say that about the D3200 too but..."</em><br /> -<br /> "That's because your camera has no AI tab to get in the way."</p>

</blockquote>

<p>And <strong>additionally</strong> and <strong>just as important</strong>, the EE post switch (at 8 o'clock, for detecting the minimum aperture position of the aperture ring on AF-D lenses) on the D3200 is spring loaded so that it moves <strong>axially into</strong> the mount when the aperture ring skirt of a non-AI lens makes contact. The D40, D60, D3xxx and D5xxx have this type of EE post switch, so they don't have a problem with <strong>most</strong> non-AI lenses.</p>

<p>This is important because there are DSLR bodies with no AI tab that can still be damaged if you mount a non-AI lens. On these bodies the EE post switch (again at 8 o'clock) moves <strong>radially around</strong> the mount, just like an AI tab ring. Mounting a non-AI lens on a body with this type of EE post switch can do the same kind of damage as mounting it on a body with an AI tab if the aperture ring skirt jams on the switch. The D50, D70, D80, D90 and D100 have a radial type EE post switch.</p>

<p>All of course irrelevant to the OP's original question about adapting his Pentax M42 mount lens. :-)</p>

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...