cguaimare Posted December 26, 2010 Share Posted December 26, 2010 <p>Hi friends: I was wondering if I use Nikon TC-20E III AF-S 2X Teleconverter with my Nikon 105mm f/2.8 Micro, would I get more than 1:1 magnification? Let´s say 2:1?? Thanks a lot!</p> Link to comment Share on other sites More sharing options...
ArthurRichardson Posted December 26, 2010 Share Posted December 26, 2010 <p>I think reverse mounting the lens will give better results. There should be many postings on this issue though....</p> Link to comment Share on other sites More sharing options...
steve_kirby1 Posted December 26, 2010 Share Posted December 26, 2010 <p>Theoretically you should get close to it, but your image quality will suffer some and so will flatness of field.</p> Link to comment Share on other sites More sharing options...
scott_murphy_photography Posted December 26, 2010 Share Posted December 26, 2010 <p>Personally I would not use a teleconverter, for reasons already mentioned. Reversing the lens is a very good alternative, but it will not get you 2:1, not with a 105mm focal length. My recommendation is to get an extension ring. If you really want to go hog wild and get even greater than 2:1, I would recommend looking into a Nikon bellows like the a PB-6. Below is a link to an image I took with my PB-6 and a 55mm f/2.8 AIS Micro lens. Magnification was around 3.1:1.</p> <p><a href="../photo/12007646">http://www.photo.net/photo/12007646</a></p> Link to comment Share on other sites More sharing options...
francisco_disilvestro Posted December 26, 2010 Share Posted December 26, 2010 <p>Reversing a 105mm will not get you more magnification, actually less. You get high magnification when you reverse a wideangle. besides, I don't know which exact model is your 105 (I suppose it is not the AIS since you mention 1:1 magnification)</p> <p>If it is the G lens, then forget about reversing it or even using a bellows.</p> <p>Using a 2X teleconverter will give you 2:1 magnification, but the results probably will be similar to just croping the image</p> Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted December 26, 2010 Share Posted December 26, 2010 <p>Francisco is pretty much right about the teleconverter. The increase in magnification that you get will be almost completely offset by the loss in optical quality that goes with using a teleconverter, especially at such a close distance.</p> <p>Using a reverse adapter may lose you the ability to focus the lens, because the front of the lens doesn't move when focusing. This might work with zooms or other intenal focus lenses, but I don't think any of the Micro-Nikkors are IF types. </p> <p>What works best and most economically depends on your camera body and lenses. If your camera only accepts G series lenses then practically the only option you have is to use AF coupled extension tubes. However if your camera will work with older lenses, then a bellows unit will give you the most flexibility. For example; I was able to adapt a nice old Pentax M42 set of bellows to my D700 by using a T-mount. This lets me use reversed lenses or enlarging lenses, via an M42 to L39 adapter, to get a magnification of up to 6:1.</p> Link to comment Share on other sites More sharing options...
dave_wilson1 Posted December 26, 2010 Share Posted December 26, 2010 <p>There are quite a few PNetter's who are really accomplished at this stuff, I'm not one of them lol, although I used to shoot engine parts up to 3x. Reverse lenses, bellows and even adding high quality diopters such as the 5T and 6T are all useable devices, a 2x conv. would be my last choice (although I have used it/decent). Also check out some of the Wed Pic regulars like Jeannine Buglady and Roberta Davidson, I always admire their fine close up work, but there are more too.</p> Link to comment Share on other sites More sharing options...
joseph_wisniewski Posted December 26, 2010 Share Posted December 26, 2010 <p>The teleconverter is the best solution for 2x magnification on a 105mm macro. It will give you higher resolution, better contrast, and a flatter field than anything you can do with a 105mm f2.8 (either the new AF-S VR or the old AF) using tubes, bellow, or attempts at reversing the lens.</p> <p>I'm sorry, this is going to sound rude, but there are so many people in this discussion who appear to never have done this stuff, repeating hearsay and old wives tales, that it's hard to refute some of this seriously.</p> <ul> <li>You do not reverse a long lens for macro use. A 105mm in its forward orientation at 1:1 has a working distance of about 120mm from the front element. Reversed and extended as far as you need to to get to 2:1, it has a working distance of under 60mm. Fransisco is right, you reverse and extend short lenses, normals and wides.</li> <li>You do not put a 105mm on "an extension ring", as Scott Murphy recommends. First, the 105 AF requires 70mm of extension to hit 2:1, the VR requires 75mm. The Kenko tubes come in a set of 3: 12, 20, and 36mm. Stacking all 3 isn't quite enough to get you to 2:1, although it's close. But they're not rigid enough to reliably put a stack of 3 on a heavy lens. I know, I've tried. And, as we'll get to in a minute, the results are not as good as a teleconverter.</li> <li><strong>"but I don't think any of the Micro-Nikkors are IF types."</strong> Actually, they all are. All modern Nikon macro lenses are either floating element (some elements move when you focus or change magnification, others stay stationary) or full fledged variable geometry (some gropes of elements move independently, at different rates, and even in different directions as you focus or change magnification). This is very important to know, because...</li> <li>Modern variable geometry macros do not do well on extension tubes. They are flat field only at the lens top film plane distance that matches the lens's current geometry. They suffer field curvature and resolution loss when used on extension tubes or bellows. (They're not very fond of diopters, either. That's pretty much why Nikon stopped making the 5T and 6T. Sorry Dave).</li> <li>You can use the variable geometry to compensate for a short macro lens's performance when used on a bellows. Basically, this only works with the 60mm. Reverse the 60, set it to 1:2, then extend it enough to get to 2:1, and you will have good optical performance. Similarly, set it to 1:3, extended enough to get to 3:1, and it does well. But it's simpler to do what </li> <li>I really liked this one: <strong>"Theoretically you should get close to it"</strong>. No, theoretically, you hit it exactly. 1x lens, 2x converter, 1x2= 2. That's not a hard "theory".</li> </ul> <p>Macro lenses and teleconverters are excellent matches. Back in the days before all the macro lenses were variable geometry, and all the macros only went to 1:2, Nikon used to recommend tubes for getting the 55mm and 105mm micro-Nikkors up to 1:1, but recommended the TC-201 teleconverter for getting the 200mm f4 micro-Nikkor to 1:1. Why? Because it worked. ;)</p> <p>If you have the old 105mm AF, I'd suggest the Kenko PRO-300 2X. If you've got the 105mm AF-S VR, the TC-20E III is the ticket.</p> <p>The biggest danger to your image quality at 2x are two of the "deadly tions", vibration and diffraction. The 105mm f2.8 at 1:1 is effectively f4 (due to extension), and on a 2x TC, it's now f8. On an APS sized camera, you'll start to notice diffraction softening of the image at f11, and it's pretty strong at f16. If your subjects aren't live, shooting wide open at effective f8, or 1 stop down at f11, and using "focus stacking" software such as CombineZ or Helicon Focus will get you the best resolution and good DOF, without limiting your resolution from diffraction.</p> <p>Vibration is best handled with a sturdy tripod, flash, and a focus rail to complete the "fine tuning" of focus.</p> Link to comment Share on other sites More sharing options...
cguaimare Posted December 26, 2010 Author Share Posted December 26, 2010 <p>Thanks you all a lot for your answers. Scott I saw your work... very impressive. Do you use that below on a tripod? Will it work with a 105mm 2.8?</p> Link to comment Share on other sites More sharing options...
francisco_disilvestro Posted December 26, 2010 Share Posted December 26, 2010 <p>Carlos, It will depend on what specific 105mm 2.8. Bellows or extensions would work with the old manual AIS. If you have the AF or the AF-S G then listen to Joseph and get the TC</p> <p>otro venezolano</p> Link to comment Share on other sites More sharing options...
cguaimare Posted December 26, 2010 Author Share Posted December 26, 2010 <p>Wow Joseph thanks a lot for taking the time for such a long and detailed analisys. It seems now a good idea to try the teleconverter.</p> Link to comment Share on other sites More sharing options...
elliot1 Posted December 26, 2010 Share Posted December 26, 2010 <p>Joseph, I had never though of using a converter with my macro lens. So I just did a quick test. My 3 extension tubes (set of 3) get me a bit closer than my 2X (Kenko) converter. And the IQ with my extension tubes seems to be is better. This could be because they are not Nikon brand, although it is my understanding any time you put extra glass between a lens and a sensor, IQ is likely to suffer.<br> I get great results with my tubes.</p> Link to comment Share on other sites More sharing options...
elliot1 Posted December 26, 2010 Share Posted December 26, 2010 <p>Attachment here </p><div></div> Link to comment Share on other sites More sharing options...
dave_wilson1 Posted December 26, 2010 Share Posted December 26, 2010 <p>Elliot, I think guys like you and I are using older manual stuff, apparently as Joe speaks the new AF-VR business with the floating elements are a different mix. Also, if I gave the impression that I would be reversing the 105, that is not so, I was unclear, poor answer, my bad. I usually reverse a 35mm or 50mm, not a 105, but sometimes I have stacked lenses for very high magnification. I have no AF macro equipment, so probably I should have taken the 5th here. 8-))</p> Link to comment Share on other sites More sharing options...
elliot1 Posted December 26, 2010 Share Posted December 26, 2010 <p>Dave, I would have to imagine that the amount of magnification would be the same (proportionally), but perhaps not. Maybe someone here can do a similar test and post the results. Even if the magnification were identical, I can't image a teleconverter giving as good or better results than extension tubes or bellows. Perhaps Joseph or someone else can post some comparison shots. The TC-20E III is highly rated and may indeed provide improved results vs tubes.</p> Link to comment Share on other sites More sharing options...
Robert DeCandido PhD Posted December 28, 2010 Share Posted December 28, 2010 <p>See here:<br> http://www.photo.net/gc/view-one?classified_ad_id=1229150</p> Link to comment Share on other sites More sharing options...
oskar_ojala Posted December 28, 2010 Share Posted December 28, 2010 <p>Joseph pretty much sums it up. Tubes/bellows (=extension), close-up lenses and teleconverters are the means to get close. For the reasons that Joseph mentions, the TC is the only practical solution with the 105/2.8 AF-S VR micro (and probably the AF-D too, although I'm not bothering to think about that particular lens). The real question is what do you want to achieve? If you need the TC otherwise and have the lens, by all means try it. If, on the other hand you have some specific scenario in your mind, this combination may or may not be the best.<br> Robert, the Macro-Nikkor 19/2.8 is intended for magnifications ranging from 15x to 40x on a Nikon Multiphot system or similar, I don't think it's quite what the poster is looking for...</p> Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted December 28, 2010 Share Posted December 28, 2010 <p>Joseph, floating elements and variable geometry are not the same thing as Internal focusing. Floating elements are for the purpose of correcting aberrations and maintaining field flatness as the focus of the lens is changed, while internal focus achieves the focusing of the lens by moving one or more internal groups of glasses with little or no variation in the physical extension of the lens barrel. Nikon's floating element CRC (close range correction) system was applied to many lens designs from the mid 1970s onward, but almost all of those prime lenses remained conventional helical focus types. Of Nikon's Micro-Nikkors, I see that the current AF-S VR 105mm f/2.8 and 200mm f/4 D are internal focus types. The 60mm Micro and 85mm PC-Micro lenses have conventional extending focus, as do all the older designs of Micro-Nikkor.</p> <p>To reiterate and clarify what I was trying to say previously: The issue with reversing a lens by using a reverse adapter alone, as recommended in some posts, is that the lens cannot then be physically extended from the camera. This means that the lens simply will not focus without the aid of additional bellows or tubes, and you're correct to say that reversing a variable geometry lens will probably give poor results, because the lens just wasn't designed to be used that way round.</p> <p>So I'll stick with my bellows and fixed lenses thanks - it's far simpler!</p> Link to comment Share on other sites More sharing options...
francisco_disilvestro Posted December 29, 2010 Share Posted December 29, 2010 <blockquote> <p>The 60mm Micro and 85mm PC-Micro lenses have conventional extending focus, as do all the older designs of Micro-Nikkor</p> </blockquote> <p>I don´t know about the 60 or 85, but at least the Micro Nikkor 105mm f2.8 AIS is not a conventional focus lens. It is not an internal focusing lens either. I guess it is a variable geometry lens. </p> <p>When you use the 105 micro AIS with a bellows, it is recommended that you start increasing magnification by focusing the lens to it closest focusing distance before extending the bellows. Nikon recommends to stop the lens down if you don´t have it set to the minumun focus position. There are even recommended minimum apertures engraved in the focusing ring to use with the dedicated PN 11 extension ring.</p> <p>Regarding reversing the lens, besides quality issues, if you reverse a longer than normal lens you get less magnification, not more. Reversing is interesting for a wide up to a normal, not for teles.</p> <p> </p> Link to comment Share on other sites More sharing options...
aaron_s2 Posted January 11, 2011 Share Posted January 11, 2011 <p>please correct me if i am wrong, but i was under the impression that extention tubes allowed for increase in working distance and TC increased repro ratio.<br> assumption 2: tubes work better with shorter macro lenses increasing working distance.<br> assumption 3: TCs increases mag but not working distance and do indeed degrade IQ.</p> <p>@Elliot: regarding your test, was film/sensor plane to subject distance a constant?</p> Link to comment Share on other sites More sharing options...
Recommended Posts
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 accountSign in
Already have an account? Sign in here.
Sign In Now