Best portrait prime lens for the Sony a7R V?

Question

I finally pulled the trigger and upgraded to the Sony a7R V after years of shooting with an older body. I’m absolutely loving the speed and that insane 61-megapixel sensor, but it’s making me realize that my current lens lineup might not be doing this camera justice. I’ve started doing more professional portrait work lately—mostly lifestyle and some tight headshots—and I’m in the market for a dedicated prime lens that can really handle the resolution.

I’m feeling a bit torn because I want something that produces that "magic" look without sacrificing the sharpness needed for such a high-resolution sensor. I’ve been looking closely at the Sony 85mm f/1.4 GM, but I know it's been out for a while now. Does it still hold up on the a7R V’s sensor, or should I be looking at the Sigma 85mm f/1.4 DG DN Art instead? I've heard the Sigma is incredibly sharp, which might be better for those high-res files, but I've always loved the color rendering and skin tones on Sony's G Master glass.

Then there’s the 135mm f/1.8 GM, which everyone raves about for that incredible compression and bokeh, but I’m worried it might be a bit too long for some of the smaller indoor spaces I work in. Another huge factor for me is the autofocus performance. With the a7R V’s new AI-processing unit, I really want a lens that can keep up with the eye-tracking perfectly, especially when I'm shooting wide open at f/1.4. I’ve had some issues with older lenses hunting in backlit situations, and I really want to avoid that frustration on professional shoots.

For those of you who have been shooting with the R V for a while, what has been your "gold standard" for portraits? Is there a specific prime that really makes those 61MP files pop while still giving that creamy, dreamlike background?

Yellow Blue · Accepted Answer

sooo TL;DR: go for the Sigma 85mm f/1.4 DG DN Art for around $1,050!! Comparison:
- Sigma Art: Cheaper, sharper for 61MP, snappy AF.
- Sony FE 85mm f/1.4 GM: Older tech, pricier, bit slower.
- Sony FE 85mm f/1.8: Best budget pick at $550 but less "magic". Best choice is the Sigma!! It handles the AI tracking perfectly and honestly saves you a ton compared to G Master glass. gl!!

MarcusHooke · Answer

In my experience, jumping up to that 61MP sensor is a total game changer but it definitely highlights every little flaw in your glass. I’ve spent a lot of time with the a7R V and honestly, you gotta match that AI autofocus with lenses that actually have the motors to keep up. Here is how I’d break it down for those high-res files: - Sony FE 85mm f/1.4 GM: Look, the "magic" is real. The way it renders skin is still special, but the AF tech is literally from another era. On the a7R V, you might find it hunting a bit in backlit scenes because it uses older ring-drive actuators. If you want that dreamlike look, it’s great, but for professional reliability, its getting tough to recommend. - Sigma 85mm f/1.4 DG DN Art: This lens is highkey a beast. Its way sharper than the original Sony GM and handles the resolution of the R V perfectly. The AF is snappier, and honestly, you can fix a lot of the color rendering in post-processing anyway. It’s a better "technical" lens for 61 megapixels imo. - Sony FE 135mm f/1.8 GM: This is the gold standard. If you can step back a few feet, JUST DO IT. It uses XD linear motors which are designed to keep up with the newest tracking tech. The sharpness is actually insane—it’s probably the best lens Sony has ever made for resolving detail. If your doing tight headshots, the 135mm is reallyyy unbeatable. But if you’re worried about space, the Sigma is the smartest play for that sensor. Also, definitely look into the new Sony FE 85mm f/1.4 GM II if you have the budget—it basically combines the Sigma's sharpness with the Sony magic. peace

Mini Moving Manhattan · Answer

^ This. Also, honestly, trying to pick between brands for a sensor like the Sony a7R V reminds me of when my cousin had a similar thing happen and it turned into a whole ordeal...

He spent weeks agonizing over whether to stick with name brand glass or save money with a third party option for his new kit.

Unfortunately, he had issues with the autofocus hunting during a really important sunset shoot because the lens firmware wasnt playing nice with the new AI tracking.

It was not as good as expected and he was so disappointed when he saw the files on a big screen later. Basically he ended up missing the best light because he was fighting with his gear... I still remember him complaining about it for months after... it was kinda rough to watch tho.