SonyFE 1.4x Teleconverter

Expensive, but well worth it if you have a 400GM or 600GM. Very little, if any, loss of image quality and it doesn't seem to affect AF speed at all. Highly recommended.

I use the Sony FE 1.4x teleconverter with my Sony A1 and Sony 70-200mm f/2.8 GM OSS II and the Sony 200-600mm f/5.6-6.3 G OSS mainly for wildlife photography. I shoot only in Full Frame so I have cannot comment on how it performs in Cropped Mode. Also, I shoot Manual with Auto ISO and use the Exposure Compensation Dial to adjust the Exposure to my liking. In most cases I shoot handheld and the important thing with the 1.4x attached is to use a shutter speed high enough. When done right I see no degradation of image quality. I get tack sharp images with or without the teleconverter. The only complaint I have is that it is expensive for what it is but I highly recommend it if you are willing to pay the price. It is a good way to get a reach up to 840mm without having to buy into the super expensive, big and very heavy long primes.

Birds are small and it is hard to get close to them. I have the Sony FE 200-600mm F5.6-6.3 G OSS Super Telephoto Zoom Lens and it is still a challenge to fill the frame with my subject when I go birding. Adding this tele-converter gives me a maximum zoom of 840 mm with a loss of only one f-stop. I now use my lens with this unit attached most of the time. The extender is very compact so you don't even notice it when it is installed and all of the lens functions operate normally. My A7-R3 camera body even records in the image meta-date that the extender is in use. The bad news is that the Sony extenders were designed to work with only a couple of the Sony telephoto lenses, so make sure that the lens that you have can be used with this extender. The good news is that since the compatible lenses were designed to go with the extender, there is practically no impact on image quality. The extender is not cheap, but you are getting a top quality piece of equipment and I put this in my "must have" category.Sony does make a 2x converter, but that unit costs you two f-stops, which is more than I wanted to loss.

It's pretty good. You lose some of the incredible tac sharpness of the 600m to reach out a little further. It's still better than using the lens without it and just cropping, so there's some added detail overall. I'm not convinced it's worth hundreds of dollars, but I got a reasonable deal and i'm happy with it.(I use an A7RIV with the 600m and this)

If you want to extend the reach of your Sony 70-200GM lens, get this bad boy.

The downside is that you’ll most likely need to f9 fstop or smaller, but with sufficient light it produces excellent clear photographs where the autofocus even works. For poor lighting conditions results can vary. I have several photos of birds that look nearly as clear and clean as photos taken without the teleconverter in good light.More experience is needed in testing conditions where poor light is present.

Really disappointed with this item. It works but only on certain lenses. I have G Master and Sigma Art 24-70 and neither will work with this adapter.

As a former Canon user, I was reluctant to purchase Sony teleconverters for fear my results would be similar to my Canon EF 1.4x and 2x converters, which seemed only ever to produce satisfactory (and marginally at that) results on a 300mm 2.8 vii lens. I can happily report that the Sony teleconverters (both 1.4x and 2x) produce stunning results - understanding, of course, their inherent limitations. The 1.4x works fabulously on both my A9 and A7Riv; the 2x really cannot be used with the high resolution A7, but produces excellent results with the A9. Keeper rates with birds-in-flight are reduced by about 40%, but that is the price of a 1200mm focal length when using with the Sony 200-600mm zoom lens. The Canon would yield nothing but blur with any zoom lens, so I'm quite happy with the results coming from both the 1.4x and 2x converters. I gulp a bit when I write this (because these are terribly expensive), but they are worth every penny if you shoot wildlife, especially birds.