1.4x Teleconverter or 2.0x Teleconverter?

[Jack Wu]

I am debating between the 1.4x or 2.0x Teleconverter and cannot decide which to get. I plan on using it with my SEL70200GM and SEL200600G mounting on Sony a9 or A7r4. Hoping that someone who had used them with their lenses and would not mind sharing some inside tips. Greatly appreciate any advice.

 

[Clix Pix]

I use the 1.4x TC with my 100-400mm and my 200-600mm on the A7R IV; in good light it works very well, and extends the focal range. Because there is some loss in light (can't go beyond f/8 and open to wider apertures) I would hesitate to even try a 2x TC on either of these lenses. A 2x TC works best with a prime lens such as a 600mm which is already a faster lens than the zooms available. Of course there is a significant price difference, too, between the 200-600mm and a 600mm prime!

 

[Jack Wu]

I use the 1.4x TC with my 100-400mm and my 200-600mm on the A7R IV; in good light it works very well, and extends the focal range. Because there is some loss in light (can't go beyond f/8 and open to wider apertures) I would hesitate to even try a 2x TC on either of these lenses. A 2x TC works best with a prime lens such as a 600mm which is already a faster lens than the zooms available. Of course there is a significant price difference, too, between the 200-600mm and a 600mm prime!

Thank you for the confirmation. I was leaning toward a 1.4x TC because the loss of light and autofocus in a 2.0x is just so great. Of course, I can always try to buy a $12,000 600mm prime but I think my wife would hand me the divorce paper at the same time the lens arrives at the house so I'm not sure if it is worth it.

 

[tcoquelin]

You should check the specs of the AF of your 2 bodies. Some have a limit of f11 for phase detection others have a limit of f8. Going past that limit has a big impact on AF performance. I have the 200-600 and I'm considering the 1.4x because it remains below the f11 limit of the A7III while the 2x goes beyond.

If my body had a limit of f8 for PDAF, i'd go for the 2x.
(I shoot a lot with a 500f8 that was T11+ so 1200f12 wasn't scaring me much )

 

[Drewid]

Currently using the 1.4x on my 100-400 and because of the winter light in the UK and where I want to shoot (forest behind my house) I am finding I am binning over 50% of my shots. Notwithstanding that comment the good shots are very good and have no noticeable loss in IQ.

 

[johonew]

I used to have the 2.0 TC along with my Fuji X-T3 and the 100-400mm lens. When I bought the A7R4, I also picked up the 200-600mm, but got the 1.4 TC...I figured the extra length on the lens was a good reason to go for teh extra stop of light with the 1.4 TC. I used it for about two months this summer shooting hummingbirds, and I was very happy with my decision.

 

[Jack Wu]

You should check the specs of the AF of your 2 bodies. Some have a limit of f11 for phase detection others have a limit of f8. Going past that limit has a big impact on AF performance. I have the 200-600 and I'm considering the 1.4x because it remains below the f11 limit of the A7III while the 2x goes beyond.

If my body had a limit of f8 for PDAF, i'd go for the 2x.
(I shoot a lot with a 500f8 that was T11+ so 1200f12 wasn't scaring me much )

Thanks for the info. I hadn't thought about that so it's great that you reminded me of it.

 

[Jack Wu]

Thank you. I'm leaning toward the 1.4x TC.

 

[SE-FL-birdsman]

I use the 1.4x TC with my 100-400mm and my 200-600mm on the A7R IV; in good light it works very well, and extends the focal range. Because there is some loss in light (can't go beyond f/8 and open to wider apertures) I would hesitate to even try a 2x TC on either of these lenses. A 2x TC works best with a prime lens such as a 600mm which is already a faster lens than the zooms available. Of course there is a significant price difference, too, between the 200-600mm and a 600mm prime!

Good reply. Also, 2x works very will with 400mm prime.

 

[Ziggy]

Do a search here - there's more info.