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Question: Will autofocus work with my D3100?
Document: It might be old, but this lens does what it needs to. Manual iris is great for high speed and locks so you don't slip out. Sturdy and affordable. It's small, so if you're using a rig, keep in mind your fingers might hurt trying to work it and you can't use a controller on it.
It's sharp, wonderful, and the perfect wideness for what I need! Especially great if you have a full frame camera, but it will work on the smaller sensor cameras as well. The fixed focal length lenses are all I use because they focus faster and are much sharper than zoom lenses.
I was looking for a small, light, fast, prime lens for my Nikon D7100 and, after some research, this seemed to be the best option available.The seller answered all my questions, the price was very fair and shipment was right on time (actually, even quicker than I'd anticipated. )The lens is absolutely in&#34; like new&#34; condition and has become my go-to lens for moderate wide angle work (30mm equivalent on the D7100.)
The distortion on the 20mm F2 AFD is severe. Straight lines do not remain straight (neither does the 24mm F2.8 AFD keep straight lines straight). I would choose the 35mm F2 AFD if I wanted a better quality lens. The 20mm F2.8 AFD is not an easy wide lens to work with. The 24mm F 2.8 AFD is a bit easier to work with for the inexperienced.
The Nikon AF20mm f2.8 was designed as a "pro" wideangle lens back in the days when 20mm in autofocus was as wide as you could get. Originally introduced in 1989 it was the AF equivalent of the manual focus design of 1984 and uses the same optical formula as the MF. The subsequent addition of the D chip has  changed nothing else. In it's day an AF 20mm was pretty radical and it was only superceeded in 1993 by wider primes as the pros sought wider and wider views.
With the full-frame sensor this lens comes alive producing amazingly wide-angled views with sharpness all the way to the corners. This is now my go-to lens for landscapes, architecture, panoramas, astrophotography, and abstract street photography. I really can't stress enough how great this lens is. I'm sure a lot of people looking at this lens are debating between this and the renowned 14-24 f/2.8 Nikkor.
When I originally purchased this lens I was using a DX camera body and was looking for something sharp, fast, and wide to replace my old kit zoom lens. While it was a competent performer, it didn't really set my world on fire. On a DX body it's just not wide enough to create wide-angle distorted close up photos where the wide aperture would come in handy.
When I first saw Velvia slides taken with this lens by a friend I was very impressed by the angle of view and the contrast and great colours. That was 20 years ago.However lens design has improved with time and few focal lengths (apart from say the 50mm lens) have not improved.I tried this lens on a full frame digital camera and noticed that it is a little soft on the sides.
Well to start off I am a professional photographer and I use this len's a lot since I receiving it. I bought it to use on a dx camera because for wedding's and event's I like the angle of a true 28mm so the 20mm on a dx camera come's close at about 30mm. I use this for all of my wide angle shot's I also prefer prime lens because I feel when I use a prime len's instead of a zoom I am more carefull in my framing and I feel less lazy.
Unbelievable, the sharpest wide angle I have ever owned. Forget the 14-24mm, save money and save some weight (this is light, solid, made in Japan)!
Answer: No