Yongnuo 100mm f2 Lens Details

I recently made a video about firmware v1.03. There are improvements in auto-focus performance, especially in live-view mode.

Here is a link to full sized example photos on Flickr:
Flickr Gallery Link

You can pick this lens up on here.

Here is a crop of one 100MM@f2 photo at 100% without additional editing:

I’d personally consider that is producing a nice amount of detail, especially without any editing. There are a large number of factors involved from the distance to the subject to others like hand/shutter shake.

The Youtube review:

Notes I wrote up while making the review:
– From the manual it lists the lens as having 9 aperture blades and a minimum aperture of f19, which is confusing because both of my cameras go to f22.
– Minimum focus distance is 0.9 meters or around 3 foot with a 0.14 times magnification. This isn’t a lens you will be getting close focus and high magnification with!
– The lens comes with caps but no lens hood. It does have a 58mm filter thread, which is a standard size.
– The lens has a nice weight to it at around 449g. It is sized around 76x83mm (3×3.25in).
– The lens exterior is a mixture of metal, plastic, and rubber. The back half is a plastic similar to the Nikon 50mm f1.8g lens, but the front is a substantial feeling metal. The filter thread is metal and is high precision machining.
– The lens comes with a USB port intended to be for adjusting the lens or adding new firmware. I recently tested v1.03 firmware!
– The lens has a built in DC type motor for focusing. It’s louder than Nikon’s silent wave motors by quite a bit.
– Most lenses in this focal length and price point are manual focus. Keep that in mind.
– The lens has a switch on the side in a standard spot to cycle between MF and AF.
– This lens does not have quick shifting capability, so you must use the switch to do manual focus. When the lens is in AF mode, the focus ring rotates freely, but does nothing. In manual focus mode you can feel the focusing elements being connected with the focus ring. The focus ring will not stop when you reach the limit on either end of focus, but there will be more resistance to rotation. This is the standard way lenses of this era work in manual focus mode.
– So far in my testing, autofocus is pretty average, but not as good as say the 50mm f1.8g that I have. The lens will get to nearly being in focus quickly, but locking sometimes takes a bit of time. Without focus beep or indicator in the camera on, it’s sometimes hard to know. I do a decent amount of focus and recompose and have had the lens try and fail to focus when I shift the camera (thinking that I had gained focus already. Focus accuracy appear to be good once it gains focus. I’m hoping for firmware improvements. The focus does feel consistent once I adapted to how the lens focuses. I was getting much better with it on the 3rd outing).
– Manual focus is not bad on this focal length and maximum aperture. The ring has a nice grip and is smooth to rotate.
– To put things into perspective, my old Sigma 100-300mm f4 lens is much less consistent at focusing than this one.
– I did take the lens out at night to a local park (D600) and didn’t have any focusing issues within my expectations. Not bad!
As of v1.03 firmware, live-view focusing on the D600 and D750 seems pretty decent in my testing so far. If you are having troubles, upgrade your firmware!
Exposure issues:
– The lens appears to not communicate properly with cameras about exposure. Maybe it’s partly because the lens reports f22 minimum aperture when the manual states f19 as minimum? It’s hard to say, but something needs to be fixed.
– With the Nikon D750 I have to apply around +2 to +2.67ev to match the exposure I was getting with my Nikon 50mm f1.8g lens.
– With the D600 I have to apply around +0.7 to +1.0ev to match the exposure I was getting with my Nikon 50mm f1.8g lens.
– I’m really hoping that the lens receives a firmware update to improve the situation. It’s not a show stopper, but a hassle for sure.
Image quality details:
– I’m liking image quality so far. I see a nice amount of detail even at f2.
– I feel like they optimized this lens to be strong at wider apertures with a much less dramatic improvement at smaller apertures. That’s totally fine with me in this case.
– Out of camera RAWs seem a bit low contrast at times. Easily fixed in post.
– The lens would probably be helped a lot by a hood. It’s odd they didn’t include one.
– Will there be lens profiles for this? I don’t stay current on Adobe stuff, but Acdsee doesn’t have a profile.
– I plan on using this lens with the D600 more than the D750. When I double up on cameras like having a wide plus telephoto. This will kinda-sorta replace the Sigma 100-300mm f4 when I feel 100mm is enough.
– USB firmware updates will be the difference between a quirky value lens and a good lens.
– I’m liking image quality from the lens. I’ll simply say the rendering is appealing outside of its tendency for lower contrast.