100-400 paired with A9/1.4x TE or A7IV in crop mode?

Started 3 months ago | Discussions thread
dcstep Senior Member • Posts: 1,255
Re: 100-400 paired with A9/1.4x TE or A7IV in crop mode?

duncang wrote:

Geekapoo wrote:

SafariBob wrote:

It's hard to tell. I think most likely you would prefer the A7RIV. Nevertheless, I believe the A9 w/tc focuses faster. The A7RIV will be lighter without the TC. Given that you were disappointed with the XT3 + 100-400, which I assume is pretty high performance, it's not guaranteed you will be be happy with the R4. On the other hand, if you do end up disappointed, you could trade up to an a7IV or a7RV whenever that arrives. You will get the tracking AF mode on both. Most of your photos are in fairly good light, which suggests the a7riv will do well.

My gut feeling is that the A7RIV might be the better choice. I gravitated to Fuji from Nikon FF to go with APS-C and reduce weight (pinched nerve/osteoarthritis issue). My RX10 IV is my daily hiking bird camera and the Fuji for dedicated bird shoots. Am bummed that for me, the Fuji is a step down with respect to AF-C...just does not track as well as the bridge zoom and when the 100-400 is paired with the 1.4x TE? Forgetaboutit.

I guess my hesitation with respect to making a decision is mainly due to the idea of buying an A7RIV to use in crop mode, as I really want the reach. The increase in resolution (if not in crop mode) plus the ability to add the 1.4x TC when in crop mode (to 840mm) does have great appeal. The downside is the AF-C may disappoint vs. an A9.

With an A9/100-400/1.4x TE I'll get to 560 and have best in class AF-C. The downside is that I'll be limited to cropping to "get closer" but, the results will be better than the crops of my 1" and APS-C files.

Other things I'm factoring:


A7RIV 5.76 million vs A9 3.6 million EVF


The A9 blackout-free live view (something the XT3 has)

Drive and focus modes dials on the A9

Overall, I think I'll get frustrated with the reach of the A9 paired with the Sony 100-400 and 1.4xTE. NOt convinced I want to go the route of the 2xTE because of loss of light and effect on image quality. Also cannot see going the route of the Sigma 150-600c/MC11 on an A9.

Damn, this is a tough decision..thanks for your comments.

Check out this https://photographylife.com/reviews/sony-fe-2x-teleconverter article and the image quality from the 100-400+TC2.

I think you will find the a9 AF works just fine with the TC2 - I shoot almost exclusively at 840mm with my a9+200-600+TC1.4. Dn't expect to get anywhere near the same performance from the a7riv.

I find that for sharp images with lots of detail it is more important to fill the frame and get as many pixels on the subject as possible. That means getting close to the subject.

I've been VERY happy with my FE 2.0x teleconverter:

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