david_gagnon

<p>Thank you to everyone who replied to this question. I did another test today and found out that at the long end of my 18-300 lens, the magnification is approximately what it should be. I am assuming that to be the case, as I was not able to get a good, measurable image far enough away to use infinity focus, but close to it. I'm sure if I had, the magnification would have been equal to my other 300mm zoom lens (Sigma 70-300). I have to admit I was skeptical of the lens, especially due to the fact that at a close focus there was such a huge loss of magnification. Now that I know about the "lens breathing" issue, i will forever remember to consider this when choosing which lens to use for a certain shot. Again, thank you for the great information and to Shun Cheung for going the extra mile with a photo comparision/illustration.<br> DG </p>

<p>Thank you sir. I hadn't thought of that. I will recheck again later to see, but I don't think I'll gain that "lost" 165mm.</p> <p>DG</p>

<p>Hello. I've been absent from this forum for quite some time but my password still worked, so here I am.<br> I recently bought second-hand a AF-S Nikkor DX 18-300 f3.5-6.3 G ED lens. I thought this lens was going to allow me to leave some of the other lenses at home. Well, today was the first chance I've really had to do so testing on sharpness and contrast versus the other lenses that I own, and I came across something that I hope is not something that Nikon is trying to pull over on us. <br> As I zoomed the lens in, the image became larger as it should. Everything was fine <em>until </em>I started doing comparisons. I found out that the 300mm end of this particular lens is NOT 300 mm, but approximately 135mm. I've checked it against my other Nikon lenses and aftermarket lenses. My 55-200mm DX Nikkor lens gets much closer. When I rack the 18-300 all the way out, the barrell looks like it's moving as it should. It just isn't giving the magnification that it should.<br> Can someone who owns this lens please compare theirs with another lens to see what the 300 end looks like?<br> Thanks in advance!<br> DG</p>

<p>I'm wondering if anyone here has had an issue using an auto focus Tamron 2X tele-extender on Nikon? It is a 2X N AFs BBAR MC7.<br> I picked it up used, and have not been able to get it to work on my D200 body with either a Nikon Dx lens nor a standard 35mm Nikkor AF lens. I guess it is possible that the continuity between one set of contacts and the other set is broken. Has anyone had an issue like this? To be clear, it mounts up fine, it just will not focus. There is no manual lever or switch built into it to override autofocus.<br> Thanks in advance!<br> DG</p>