Reasonably sharp even wide open. I will not hesitate to use this lens wide open, unless I need more depth of field.

• +

  Nicely sharp, light for its length

• -

  Bokeh is only so-so

An outstanding lens that is very sharp--and rugged. I was half way around the world doing two weeks of intense shooting when the lens fell front first four feet onto the floor of a bus. It smashed the UV filter and I thought it was done for.

I used this lens to shoot acrobats at night during practice. This is not my usual style of photography but I was impressed with how well I was able to acquire focus using this lens and a 645z at night, outside with a few LED lights. Image quality is good, very correctable chroma is visible.

I'm a fan of the long lens. It's a craft of its own right so be prepared to study it's limits. Love the lens.

The image quality is very good, also the sharpness. It's not as simple as to produce the 28-45 permanently sharp images.

• +

  Manual focus, tripod mount, weight, image quality, sharpness

• -

  Aberrations, image stabilizer No;-)

CA is heavy! its the worst lens i own... I have FA* 24, 28-70, 80-200 and a lot more but this FA* 400 is with quite some distance the worst lens regarding CA i have ever used on the

• +

  Weight, size, reach on APS-C, Sharpness

• -

  CA can be terrible, silver finish

I already own the DA* 60-250 and found that I wasn't getting the reach needed to capture birds in flight as well as other wildlife. I found this lens by chance on my local craigslist. AF is a bit tricky and can easily be engaged by accident - not something I find desirable as I only shoot manual.

• +

  size, weight, sharpness

• -

  slow aperture

As I already owned a FA*600, and a DA*300 I bought this lens for a dedicated mission : an hand-holdable, lightweight lens for travel, birds in flight, and tricky approach of birds, with more reach than the DA*300 and better than a DA300 + a converter. It met 90 % of my expectations.

• +

  Sharpness stopped down, light and compact

• -

  CA, autofocus hunts sometimes, price on second hand market

As a 400mm lens, this is small and hand hold able. It is about the same size as DA*300/4. Image quality is excellent, but DA*300/4 is still a little bit sharper at f/5.6 and if you crop the image from DA*300/4 to the same size as from FA*400, it is difficult to see any difference.

• +

  Small

• -

  A little slow at f/5.6

The lens is quite light and very sharp when used at high shutter speeds or very secure tripod mount at lower speeds. It doesn't have the build quality of * lens, but the optical quality is in the same league.

• +

  sharp, light, not expensive

• -

  not f/4, but then it wouldn't be light