amfoto1 Loc: San Jose, Calif. USA

Hi Fran,

Better than getting a teleconverter...

Instead, get a DX camera!

A D7100 or other 24MP DX model will give you the same resolution as your FX D750, but with the effect of a 1.5X teleconverter.... without added optics to degrade image quality (a little or a lot, depending upon the particular TC and how well the lens works with TCs)... and without the loss of a stop of light (causing AF to slow, hunt or fail).... both of which occur with an actual 1.4X teleconverter. Auto focus performance and image quality will be better than using the lens with a TC on your FX camera.

If you shop for a used or refurbished camera and/or buy one of the more entry-level models, the cost may not be much more than that of a high quality 1.4X TC, too.

nikonkelly Loc: SE Michigan

for a nikon lens, you need the correct Nikon TC... for a Tamron lens, you need the correct Tamron TC. The tamron TC might fit the Nikon lens, but it will work best on a tamron lens... a Nikon TC will only fit a Nikon Lens. So if you have different brands of lenses... you need different TC's
kelly

RolandDieter

Many cameras will not autofocus at f/8 or narrower, so you may not be able to autofocus with that lens and a TC. Try both TCs at a store - usually the camera brand one works best, but sometimes a lens manufacturer makes one that is uniquely well paired to specific lenses they make. Sigma once made lenses that lied to the camera so that you could use a f/8 lens and a converter -- the lens just lied to the Canon cameras and electronically claimed it was an f/4 being used in lower light. I had great luck with it.

JohnH3 Loc: Auburn, AL

I would encourage you to try the lens on a crop frame sensor camera. Doing so will give you a 960mm equivalence. I have the Sigma version of basically the same lens. I have a full frame Canon camera and a Canon crop frame camera. When I need to reach out a little further, I put the lens on the crop frame camera and get good results. You will actually get more reach putting the lens on a 1.6 crop frame rather than using a 1.4 converter. I really don’t notice lot of IQ sufferage. Always good to have two cameras anyway! 😜

Ben's nana Loc: Chesterland, Ohio

John,
My D750 has an option in in the menu to shoot as a crop frame. I also have a D500 and have used that on multiple occasions. I was just hoping to get in closer. It seems as though to do what I would like to do without IQ compramise requires a very expensive lens. That is not an option. I love shooting birds and wildlife, but that expense I cannot justify.
Fran

drklrd Loc: Cincinnati Ohio

These days best bet is one that matches your camera and specifically branded the same as your camera. The cheaper ones will not be as sharp as the brand that matches your camera.

Ron Dial Loc: Cuenca, Ecuador

Keep in mind that a 2x teleconverter cuts you light in half.

JimH123 Loc: Morgan Hill, CA

As far as I know, Tamron does not make dedicated TC's, and all their TC's are general purpose.

I have a Tamron 1.4x TC, and I really don't like the results. I also have the Kenko 1.4x. And it seems a tiny bit better, but not exactly results that I like. I also have the Tamron 150-600, and using it at 600mm with a TC is just not good.

I also have several old Asahi Pentax Takumar SMC primes with m42 mounts. (200mm, 300mm, 400mm, 500mm) And when using a TC, they actually do better than the Tamron 150-600 does with a TC. But it is also manual focus too.

I have also experimented with front end TC's such as Olympus TCON-17X with is 1.7x, and the Minolta ACT-100 which is 1.5x. And they actually work better than conventional TC's. But they won't work on a lens as big as the Tamron 150-600.

imagemeister Loc: mid east Florida

The 750 is not a good camera for cropping. You will be further ahead by getting a good later model crop frame body ( 20+ MP). With either the TC or crop body, you will need very good stabilization technique - ie NOT handheld !

If you insist on full frame, you will need a higher MP body so you can crop - and use pixel enlargement software if needed. - and, of course, the final answer is a 600mm f4 lens - with TC and a very LARGE tripod - and someone to carry it.

..

sterrill Loc: missouri

My Nikon teleconverter won't work on my sigma 150 to 600mm. It might be best to make sure the Teleconverter works with your particular lens.

RickL Loc: Vail, Az

Tamron gives recommendations for TC's that they match to your lens

There are a number of pros that use TC's successfully. Check u tube check reviews for your lens and some of them explain how to chose the right teleconverter.

Rick

JohnH3 Loc: Auburn, AL

Yes, a lens beyond the Sigma or a Tamron 150-600 starts getting pricy. I feel your pain on that one! John

Karl's Bird Photography Loc: Oregon

I'm 70 years old and shooting with Canon 5D4, 600mm f4, 2.0 TC (all latest versions), and switching more and more from tripod to hand-held (often using a tree or fence to steady myself) for most of my pictures... tripods are great, but they add weight and slow you down for fast moving birds. It seems like there's never enough mm so I recently bought a short extension tube so I could stack the 2.0 and 1.4 TC resulting in 1680mm. This setup does require manual focus and a tripod... the results are sharp. If you have a high-end lineup, then it works out great... very expensive, but I was frustrated with being underpowered and I'm not patient enough to always wait for the birds to come to me. For the 600 + 2.0 TC (my usual setup) hand-holding works when there is enough light for a relatively fast shutter speed (1/800 to 1/1000, depending on the bird's movements). I also have done some upper body workouts to make it easier holding the beast. Also, the 5D4 handles low light with high ISO much better than the 7D2 that I started with. From my experience, there is negligible loss in image quality with TC's and high-end equipment... with bodies like the 7D2 you give up some ability to add TC's. In addition, because of the low-light capabilities and more pixels of the 5D4, results are better with a full-frame body and cropping than a crop-frame body and not cropping (5D4 cropped vs. 7D2 straight).