Sirui SIRUI Astra 100mm 1.33X Full Frame Auto Focus Review

If you're looking for a full-frame anamorphic lens that won't break the bank, the Sirui Astra 100mm is a pretty unique option. It's Sirui's first autofocus anamorphic for full-frame cameras, offering that classic 1.33x squeeze for cinematic widescreen footage. With a 44mm image circle, it gives you full sensor coverage on cameras like the Sony A7 series or Panasonic S5 II, so you get those stretched flares and oval bokeh without cropping. At $849, it's positioned as an accessible entry point into anamorphic filmmaking, which is a world usually reserved for lenses costing thousands more. It's a 100mm prime, which is a telephoto focal length, so it's great for close-ups, interviews, or detail shots where you want that anamorphic character.

This lens has a clear specialty: getting that anamorphic look. The 1.33x squeeze is constant, so you get the horizontal flare and oval bokeh at all times. The dual flare system lets you choose between a classic blue anamorphic flare or a more neutral one, which is a nice touch for creative control. In terms of raw specs, the autofocus lands in the 45th percentile. It's not the fastest or quietest system out there, but for controlled video shoots where you might use manual focus anyway, it gets the job done. The image stabilization is solid, ranking in the 85th percentile, which is a huge help for handheld video work on cameras without in-body stabilization. Where it shows its budget nature is in optical quality and build. Optical performance is in the 35th percentile, and build quality is only in the 15th. Don't expect Zeiss-level sharpness or a tank-like metal body. It's a plastic build that gets you the core anamorphic effect.

At $849, the Sirui Astra 100mm's value is entirely about the anamorphic look. You are absolutely paying for the 1.33x squeeze and the flares, not for exceptional optical purity. For a filmmaker who wants that distinctive cinematic style on a full-frame camera without renting a $10,000 lens, this is a compelling tool. Just know you're making a trade-off: you get the anamorphic character, but you accept average build and optics. If you don't specifically need the anamorphic look, a standard 100mm prime from Sigma or Sony will give you much better image quality for the same money or less.

This lens exists in its own niche, but let's look at some alternatives. If you want anamorphic but need more flexibility, the Sirui 35mm or 50mm anamorphics offer wider focal lengths. For a standard prime at a similar price, the Viltrox 35mm F1.7 is much smaller, sharper, and has a wider, more versatile focal length, but of course, it's not anamorphic. The Meike 55mm F1.8 Pro is another sharp, standard AF prime that outperforms the Sirui in almost every technical area except for the one thing that matters: it can't create an anamorphic image. The Panasonic 14-140mm is a superzoom for Micro Four Thirds, so it's a completely different tool for a different camera system. The bottom line is, you only cross-shop the Sirui Astra with other anamorphic lenses. Compared to them, its price and autofocus are its main advantages.

So, should you buy the Sirui Astra 100mm? Only if you are specifically chasing the anamorphic look on a budget. It's not a great all-around lens. Its 100mm focal length is tight, the build is lightweight, and the optics are just okay. But if you're a videographer or indie filmmaker who dreams of oval bokeh and horizontal lens flares, and you shoot on a full-frame mirrorless camera, this lens unlocks that style for you at a surprisingly accessible price. Think of it as a creative effect lens, not your primary workhorse. For that specific purpose, it's a pretty cool tool.