I most often use this teleconverter with a Sigma 150mm macro and a D700. That is not to say I always use the 1.4x with the 150mm, but when I do I get very good results. As a 210mm telephoto or as a macro the images are sharp with good contrast.

Easily Interchangeable; Lightweight; Rugged; Sharp Focus; Strong Construction

Bringing you this site is my full time job (typically 60-80 hours per week). Thus, I depend solely on the commissions received from you using the links on this site to make any purchase. I am grateful for your support!

Works well with the Sigma 150-500 APO HS zoom on my Sony Alpha to give that little extra range. No noticeable lens distortion introduced compared with zoom lens on its own.

Converters often get bad press. Perhaps they deserved it about 20 years ago but modern ones are really much better than those early models. The Sigma EX 1.4x APO Converter is an excellent and extremely versatile little accessory capable of extending the range and usefulness of many lenses and in my...

Hugely versatile ;  Compact ;  Light ;  Inexpensive .

None

Works Great. expect to take some time with your camera "autofocus fine-tuning" to get the best results, I suggest the slanted yard-stick around the distance you expect to shoot. Great results for birding with the 120-300 f 2.8 Used it with 500mm in manual focus.

Easily Interchangeable; Strong Construction

NONE

I use this TC with the Sigma 150mm f2.8 Macro (pre-OS) on a Nikon, and the results are outstanding. Even with the D800 the ensamble is sharp enough at full aperture ("f4"), and a razor when stepped down. Almost no decay in the bokeh and absolutely no CA in any condition. But, but...

Awsome with 150mm Macro

No AF over f5.6 (Nikon); de facto only for Sigma lenses

This was a hard to find item. Sigma has discontinued it. I have their 180 f2.8 macro lens for which this converter is used. It works well. Some, but very little drop in resolution. I have other converters, but wanted this one to match the Sigma optics of my macro. It was a good choice.

Typical of the better Sigma lenses, this teleconverter does its job extremely well. As indicated though, it is designed to be used with Sigma lenses. I use it consistently with their 100-300 zoom for wildlife and it allows auto focus with my Minolta.

Consistent Output; Durable; Rugged; Sharp Focus; Strong Construction

A one trick pony

Bought this to work with a Sigma 70-200mm OS f2.8 and does exactly what it should do. Maybe a tiny loss if IQ but overall not enough for me to worry about.

Durable; Easy to Use; Lightweight

Best for 70-200 F2.8 for little more reach. Be sure to switch off the camera, remove the lens, connect converter to lens first, not to the camera body. Then attach lens with converter to camera body, then switch on.