I use this almost entirely hand held either bracing with knees or using higher iso. At small apertures it goes soft, so using practical f stops for DOF, it goes soft a lot. And hand holding requires larger iso creating noise. Topaz does a reasonable job sharpening and reducing noise if you are careful to inspect results before choosing settings. The extension of the tube is less desirable that the built in zoom of the 70-200. Overall, I get cleaner images with the 70-200, but using a 2X teleconverter is a bit of a pain. I take the 70-200 into narrow slot canyons, and take the 100-400 into the larger open spaces. I can use a tripod to lower the iso, but unless I focus stack, I have to live with the softness. I think all these are just the tradeoffs of making lenses. ... MoreI use this almost entirely hand held either bracing with knees or using higher iso. At small apertures it goes soft, so using practical f stops for DOF, it goes soft a lot. And hand holding requires larger iso creating noise. Topaz does a reasonable job sharpening and reducing noise if you are careful to inspect results before choosing settings. The extension of the tube is less desirable that the built in zoom of the 70-200. Overall, I get cleaner images with the 70-200, but using a 2X teleconverter is a bit of a pain. I take the 70-200 into narrow slot canyons, and take the 100-400 into the larger open spaces. I can use a tripod to lower the iso, but unless I focus stack, I have to live with the softness. I think all these are just the tradeoffs of making lenses. I don't see anything that suggests anything other than high quality.

I have used the Sony G 70-300mm lens along with the Sony G 24-105mm lens for nature hikes but purchased the 100-400mm GM lens to gain more reach for wildlife. It is not a cheap lens, but the photo quality is amazing, and you can easily see difference between it and the less expensive 70-300mm lens. Yes, it's sharp. But there's also something else that's hard to put into words. The images just look better.This is not a lightweight lens, and I'm definitely not a weightlifter. However, it's just light enough to carry and use handheld for half a day or so. It actually weighs more than my camera body...I went back and forth between this lens and the Sony GM 200-600mm since the latter is a better range for bird photography. I do wish the 100-400mm had a short throw ... MoreI have used the Sony G 70-300mm lens along with the Sony G 24-105mm lens for nature hikes but purchased the 100-400mm GM lens to gain more reach for wildlife. It is not a cheap lens, but the photo quality is amazing, and you can easily see difference between it and the less expensive 70-300mm lens. Yes, it's sharp. But there's also something else that's hard to put into words. The images just look better.This is not a lightweight lens, and I'm definitely not a weightlifter. However, it's just light enough to carry and use handheld for half a day or so. It actually weighs more than my camera body...I went back and forth between this lens and the Sony GM 200-600mm since the latter is a better range for bird photography. I do wish the 100-400mm had a short throw like the internally zooming 200-600mm one. But at the end of the day, I chose portability over reach and am quite happy with the choice. The other lens is just too large for me to realistically pack and carry.Anecdotally, I also tried the Sigma 100-400mm F 5-6.3 lens and was not pleased with missed auto-focus on burst shots or the actual image quality. It's not really a fair comparison since the Sigma is much more affordable. But the Sony lens, for me, had better auto-focus performance and image quality (actually the Sony G 70-300mm was also superior and remains my choice for long hikes when the 100-400mm is too heavy). The build quality of the 100-400mm is also superior over the Sigma, and it is compatible with Sony's teleconverters. The Sigma also has a fairly long (and variable) min focal distance and was not convenient for close-up shots of flowers and bugs on a narrow hiking trail.100-400mm is useful range for most things on a hike except wide landscapes (assuming you have enough light since the Sony 100-400mm lens isn't particularly fast), and I highly recommend this lens if it is within your budget. It is a worthwhile investment you will enjoy for years.

When I first purchased a tele lens, I went with the tried and true 70-200. It was fine, but I kept finding myself wishing I had more reach. I opted to sell that in favor of this 100-400. Although I wish it had a wider aperture, I do love this lens. I've had no issues with sharpness throughout the zoom range. The image stabilization is effective. The zoom and focus rings move easily, but not too easily. I appreciate I can modify the friction of the zoom ring on the fly. When tightened I've had no issues with creeping. Autofocus is fine, but I'm not doing any fast action shooting, so I can't speak to the speed. For my use it is fine, but I typically use manual focus.