Teleconverters, Questions, Thoughts? (Canon, DSLR, Nikon, lenses)

[Cape Cod Todd]

Hello.
I have a Nikon DSLR3100 and use it with a Nikon DX 18-55mm and a Nikon DX 55-300mm.
I thought about getting a even better zoom but WOW the Prices!
I'm not a pro.
I understand you get what you pay for but I can't spend alot say up to $300.
I thought about getting a teleconverter but there are so many brands and types out there and all with good and bad reviews so it is very difficult to make a decision.
I'm looking at
Tamron,
Vivitar
Bower
Sigma
Do you have any experience or thoughts on any of these?
Thanks

[EinsteinsGhost]

An issue with TC will be that these slow lenses will get slower and may not even auto focus. You could improve your chances by using a 1.4x TC instead of 2x.

[415_s2k]

If you get a teleconverter, make sure you get a decent one by Nikon, Sigma, Tamron, etc that actually has glass in it. The ones that don't are cheap and do more or less nothing. Some of the higher-quality models by the above companies have contacts that will allow your camera to autofocus; I have a Nikon teleconverter that allows my AF-S VR lenses to operate per normal. A cheaper Bower models I tried didn't work properly, so it was all manual focus... which is fine for me, I prefer manual focus most of the time. The problem is that the Nikon AF-S teleconverter is pretty expensive, about as much as a decent used lens... so, weigh your options heavily before you buy!

[johnrex62]

I shoot with Canon, and the L series lenses will not function with most non-canon brand TCs. The design of the lense component makes it so that the L series lens will touch the TC lense elements before the lens mount seats.

I am not familiar with the Nikon lenses, but be sure you verify both the physical fit as well as the electrical compatibility.

Assuming you have a TC that will actually work with both your camera body and lens, then the question becomes functionality and quality. The added focal length and glass will reduce your light and slow the exposure. This can make some lenses lose their autofocus ability. While manually focusing is usually practical, it does make a difference in how you take pictures and can be very unappealing with the manual focus rings on many newer lens models.

The quality aspect will vary from TC model and even from specific unit. Just as each individual lense can have aberrations, a TC can also vary in performance. For most of us, it is not a concern. Our photos are not going to be blown up to make a wall covering or subjected to the intense scrutiny NASA or the airforce might apply to some of their shots.

You will see some degradation in the fine focus and out to the edges of the image where the lens creates some distortions. I find that for my use this is very acceptable. I have a couple lenses that I will not use the TC with just because the lense quality is not that good to begin with and I dont want to loose any more (cheap consumer quality lenses), and a couple others that are just so nice that I can't bring myself to sacrifice the quality (pro L series). Most are within those extremes and I love the extra reach the TC gives me. I have both the 1.4 and the 2x Canon TCs. I love them, but as with any tool; recognize their limitations and make the necessary accomodation.

[WEmoveU]

Cape Cod Todd,
As far as I remember D3100 won't autofocus with older "screw-drive" AF lenses since there’s no build-in AF motor.
3rd party TCs you’re looking at are all screw-driven, so your lenses will not auto focus. The only option you have that might provide AF is Nikon AF-S Teleconverter TC-14E II
AF-S Teleconverter TC-14E II from Nikon
Kit lenses provide decent image quality. TC will only degrade it. You’ll get better results by cropping images in photo editing software to the equivalent field of view of that TC.

[mathjak107]

i would not use a teleconvertor on any lens not at least f2.8 and where auto focus works. many nikon lenses will not even accept the nikon ones.