Revet Loc: Fairview Park, Ohio

I want to get a 1.4x teleconverter for my D7100. Mostly to use with my new Sigma 150-600 lens but occasionally with some of my others (Tamron 18-270mm, Nikor 35mm 1.8, Tamron 60 mm Macro).

Since I mostly will use it with the Big Sigma lens, does it make sense to buy the Sigma one??? If so, I see used ones are available for $170 or so. Is there any advantages or improvements in the new $300 dollar newer version??

If it is acceptable to go with other brands (Nikon, Tamron, Tokina, etc)?? Any thoughts here assuming I will be using it mostly with the Sigma lens. I have read posts about teleconvertors not fitting or working with certain lenses; thus the reason for this post.

Thanks for any input.

wingclui44 Loc: CT USA

Don't expect too much from a slow big zoom with any tele-converter!
You will disappointed.

Jahawk Loc: Rhode Island

I use the Kenko MC4 DGX 1.4 on my D7100 with my 80-200 f2.8 af D lens.
I tried it on my other lenses and have had no problem

robertjerl Loc: Corona, California

The Sigma converters are made to work with Sigma lenses, and only some of those. I know, I bought one and then found it wasn't meant for any of the lenses I own. always read the small print and specs

The Kenkos seem to have the best rep for working with almost any lens, esp the higher end Pro line. I have the 1.4 and 2.0 for my Canons. You do need to check and make sure no elements will project and touch each other or the mirror, bad things can happen, the Kenko's elements are recessed to prevent this.

You will lose auto focus with the 150-600 and many other lenses, not enough light gets through for AF to work. I don't know about your Nikon, but my 7DII can auto focus at f/8.0 on the center cross point so my extenders will work on any lens that is fast enough to stay f/8.0 or better.

Your Nikon will see the image in the 150-600 as a 900 equivilent at max, so it should work in most circumstances. Of course there are times when an observatory telescope won't seem like enough, you just have to live with it.

the 1.4 extender adds 1 full stop, and a 2.0 adds 2 full stops

Bugfan Loc: Toronto, Canada

Teleonverters are no longer like in the film days when they attached to any lens of any brand. Now they attach to only some lenses and not even to all brands. This is partly a marketing issue I bet but it's also a practical issue, some lenses just aren't designed for a TC.

That said I tend to prefer to stick to brands. I have two Sigma teleconverters for Sigma lenses only in fact for the 150-500 as well as a 150 mm and 180 mmm macro lens. They connect flawlessly and tight and they are optically lovely. At the same time I also have two Nikon TCs that I use with my Nikon lenses. These are an amazing quality and enable me to use my high end Nikon lenses to good effect. I've not tried a Sigma one on a Nikon lens or a Nikon on a Sigma lens though I expect both to work with both brands.

What is also interesting to note is that if you ask Sigma if their TCs work with Nikon they will tell you they can't comment, all they will tell you is that their TCs are designed for optimal performance on their lenses. Nikon takes the same attitude. And it's fair. Each maker designs their lenses with particular optics and so the TC is optimized for that specific design family.

There are some makers like Kenko who develop TCs apparently for all brands and all lenses. I don't buy the "all lenses" part. Some lens designs these days have lens elements going beyond the lens mount. A teleconverter could crash into those elements causing some damage. So if you use a generic TC, test it very carefully before you mount it and use it.

Recognize too that general TC designs can only approximate what's needed optically to enable a lens to perform optimally. So don't expect superior performance from something like Kenko. You won't always get it.

So this is a long winded endorsement. Use Sigma TCs with Sigma lenses, use Nikon ones with Nikons and if you decide on only one be aware that it may not work as well on the other brand. Be aware too that you can't attach them to all lenses.

Revet Loc: Fairview Park, Ohio

Thank you for your thorough reply. I just had a feeling that one should stick with a teleconverter or the lens you want to use it with. Now I would ask you (or anyone else) is there much difference optically between the new older versions of Sigma's teleconverters. They have some used ones on Adorama and B&H that are half the price as the new model

Bugfan Loc: Toronto, Canada

I would hesitate to suggest anything definitive and then only in terms of Nikon. None of the makers is going to tell you an older TC is less than optimal they will tell you instead that the new one is much better.

I found with Nikon they've changed model numbers over time leading me to suspect that the newer ones probably also represent the state of the art that year. In terms of Sigma, they are in the process of renewing their lenses so it would follow that their TCs will be refreshed eventually too.

I imagine an older used one will work just fine. I think the only changes would mostly be the odd new coating. I suspect that optically they're probably the same. Alas all of this is conjecture, I don't have an old model to compare against a new one. Perhaps there is a review page somewhere that can do that for you.

The other thing to realize is that you're already compromising your image a little by using a TC so I don't imagine the compromise is going to be noticeable if you use an older TC too.

wizbird Loc: Burnt Store Marina, Punta Gorda, Fl

Tele converters are not worth the money . Better off just cropping image.

MtnMan Loc: ID

You should look at the specs for the teleconverters. They tell you what they work with. I know there is a problem with using the Nikon teleconverters with a Sigma lens because of metal tab on the Nikon teleconverter. You can remove the tab but I wouldn't. I am not aware of problems using the Sigma teleconverter with Nikon lenses in general although some Nikon lenses, such as the 28-300, might have an interference problem with the rear element of the lens.

I also know that the Sigma teleconverters have much smaller diameter glass in them than the Nikon. To me that means you will lose more light with them.

You will lose light so your camera needs to be able to autofocus with f8 for autofocus to work. I know my D800 and some other recent Nikon's do but don't know about the D7100. You should check if autofocus matters to you.

PS: If MT Shooter chimes in you can rely on his information. If he doesn't show up here you can send him a PM. He is by far the most knowledgeable UHHer on this stuff.

speters Loc: Grangeville/Idaho

Telconverters never attached to just any lenses, not in the film days at least! They have always been brand specific and then only attached to certain models!

Bugfan Loc: Toronto, Canada

I bought my first teleconverter around 1972. At the time I had three brand name lenses and that generic TC. I added eight more lenses while I stayed with film. It attached and worked with all of them too. I bought an off brand lens as well and it attached and worked with that.

As I got into macro work I experimented with it too. To my delight it mounted on the back of my extension tubes and it mounted on the back of my bellows as well. The images weren't anything to write home about, but the TC did work.

I do remember there was the odd lens that was recommended as standalone because some of its internal elements extended into the mirror box. So those you couldn't attach. But then I never owned any of them so I never noticed and besides, most of them didn't benefit from a TC anyway.

What I didn't do was try every lens and brand on the market. So maybe you are right. Maybe TCs never attached to any off brand lens at all even when it mounted on the camera. Maybe my experience was a fluke that others did not experience when they tried something similar. But certainly based on my personal experiences it was easy to assume that you could use it for any brand of lens that fit on your camera. It worked for me.

But ok if it makes you happy "Some people insist that TCs never connected to all lens brands in the film days. Apparently they only attached to brand name lenses and then only to a few. I stand corrected". Thanks for clarifying my experience with TCs.

gkuep1945 Loc: Dowling Park, Florida

I had a Sigma 50-500mm lens and Sigma 2X Teleconverter which worked fine. I have since sold them.
I tried the 2X on my new Tamron 70-200 f/2.8 and it would not fit, physically. The protrusion of the lens and the glass of the 2X were not agreeable and hit before closure. So I know you should do your research to ensure a fit.
(That is why I sold the 2X with the Sigma lens.)

imagemeister Loc: mid east Florida

I would NOT recommend any TC with that lens. You are much further ahead cropping and using well applied pixel enlargement software.

Regis Loc: Coeur d' Alene, Idaho

The Canon 1.4x III used with the Canon 7D Mk2/Canon 100-400 II is well worth the money. My many posts prove it.

hpucker99 Loc: Anchorage, Alaska

There was this thread earlier this year on the Sigma teleconverter/lens combo.

http://www.uglyhedgehog.com/t-331274-1.html