What is the difference? I am looking to buy a teleconverter, but I could not find much information about the D, so I am wondering why there is such a difference in price between the two of them. If anyone can help me out I would greatly appreciate it.
I'm afraid I don't know the difference between these two products. When Sigma added the DG suffix to its lenses and teleconverters, as far as I can tell they never said what the improvements actually were.
Either way Sigma states that its teleconverters should only be used on the lenses listed here. That list does not include the 300mm f/4 you have listed in your profile nor any other Nikkors.
I use an older Kenko Teleplus Pro 1.4x with my 300mm f/4 and find the two work well together. I would recommend the Kenko over either the Sigma's or the older non-AF Nikon TC's.
One of the biggest mistakes a photographer can make is to look at the real world and cling to the vain hope that next time his film will somehow bear a closer resemblance to it. - Galen Rowell
I have the older D version and believe that the only difference is that the new DG has anti-reflective coatings on the rear element to reduce reflection off a digital sensor. I don't have it with me but I don't believe it has lingage for a screw driven lens.
Also I've found the the Sigma TCs can be hit or miss when using on Nikon lenses. Example, the Sigma TC seems to focus ok with my Nikon 70-300 VR but work at all with my Nikon 80-200mm f2.8 af-s. I can't even shoot a shot as it lock up my lens and camera.
Cameron, The Kenko TelePlus Pro 300 DG 1.4 is used by many Nikonians. It works on both AF-D and AF-S lenses. The Nikon TCs only work on AF-S lenses. I've used mine on the 80-200 f/2.8 AF-D, 70-200 f/2.8 VR and 70-300 VR with no issues.
Hope this helps...JL
________________________________________ 45+ years of Nikon ownership and counting Visit my SmugMug gallery
>Thank you for the additional information Jeff! I assume that >you too recommend the Kenko over the Sigma?
I don't have the Kenko but do have it's Tamron twin that works well for me on my non-Sigma lenses. From my experience the Sigma work very well with Sigma lenses. I use mine with the Sigma 150mm f2.8 macro and has almost no degradation of sharpness. So yes for use on a non-Sigma lens I would recommend the Kenko.
>Okay— looks like I will definitely be buying the Kenko. >Thanks again Jeff!
I'll add that I purchased all of my TC used. When I go my Tamron 1.4 TC (As I mentioned it's supposedly the some as the Kenko 1.4) I wasn't in the market for one. I ran across it in the for sale forum for $75.00. It's in great shape. I'm not fond of the light grey coloring but for the price it work for me.
My recollection is that the difference between D and DG is the "coatings for digital" - this was claimed by Sigma for the lens releases marked the same way. I presume that applies equally to the TCs. In practice I have never seen an effect. There are only two lenses for which I've ever been able to find a "digital coatings" problem, and they are the popular Nikkor 50/f1.8 AFD and the much older 55/f2.8 AIS Micro-Nikkor. Both of them can show a small, fairly bright orange circle in the center of the image under very specific, very high contrast situations. 99.999% of the time there is no difference. Other lenses in similar circumstances such as the 50/f1.4 AI show no ill effects. An example from the 55 Micro:
This one was produced with two SB flash units bearing at 45° at fairly close ranges. (SB-900, SB-600.)
I have never seen a similar problem with any Sigma, Tokina or Tamron lens, including some of my 1970s ones. This notably includes an older, pre-digital-coating Tamron 90/f2.8 AFD. I had a Sigma 2x APO EX D TC but I seriously doubt I ever had it in that kind of circumstance since the only lenses ever mounted on it were the Bigma and a 120-300/f2.8 HSM. I would say that these two TCs are functionally equivalent.
As an aside, note that the Sigma TCs have no screwdriver AF coupling whatsoever, so AF is physically impossible with screwdriver AF lenses. And for completeness, at least the older versions are not fully compatible with Nikkor AFS lenses either.