Difference between AF and manual focus lenses

[Pancolart]

I'd like to point just one. Correct me if i am wrong (i have very little experience with AF lenses) but AF lenses mostly move front element to focus (it's lighter, easier and faster for AF mechanism to turn it). Whereas MFlenses mostly move whole system away from film/sensor. Thus optical design with AF must be different to emphasize front element (or group) impact on focussing.

[poilu]

AF move elements with plastic gear
It doesn't take long for an AF lens to be out of spec
MF lenses have also lenses with movable blocks
they need to be adjusted after some years
manual lenses with fixed block stay top forever

[visualopsins]

AF lenses often lack aperture adjustment ring -- aperture must be operated via camera.

AF lens focus ring is often tiny compared to MF lens ring.

AF lens focus throw is often very short, making for difficult manual focus accurace as small change in ring position makes big change in focus.

[dimitrygo]

[iangreenhalgh1]

For me, the big difference is modern Af lenses are like cheap plastic toys, whereas old MF lenses are built to last in most cases. I don't want to play with toys I want to use proper tools.

[Attila]

AF lens ? what ?

[noddywithoutbigears]

[adent]

I have 3 auto focus lenses for my Canon T2i (550D). They are as follows: 18-135 / 3.5-5.6 , 55-250 / 4.0-5.6 , and 50/1.8. They rarely leave the camera bag. I just don't like the feel or the look of them. Since I discovered that I could get solid metal lenses that would adapt to my camera, I seem to have lost interest in them. The only thing I had to give up for the solid build quality is a little speed. I don't mind taking my time to get a good shot. Of course there is also the fact that you can often get a much better optical quality lens for a lot less money using older MF lenses. That was a big draw for me. The prices on L series lenses was way out of my budget.

[NewStuff]

Apart from my Sigma 55-200, the only AF lens I still use is my Sigma SuperwideII. Thing is, the AF is broken. The 55-200 is sharp for the price(I think I paid £30), small enough, and good as a general purpose carry round, as the missus tends to be impatient with my futzing around trying to get the Focus bang on. You can score some bargains buying lenses with a broken AF system, but still stop down correctly.

As mentioned though, the ring or grip for the focus tends to be small on most AF lenses... more of a nod to an "emergency" situation should the AF not be able to function, rather than an intention to use it all of the time. The build quality is also, as a generalisation, much lower.

[ManualFocus-G]

I've accidentally collected some AF lenses recently.

I have:

Canon EF 50/1.8 II - Cheap but OK - not very inspiring - easily prefer Planar 50/1.4
Canon EF-S 18-55mm IS - Cheap but good value for money, much sharper than the non-IS version - prefer Vario-Sonnar 35-70/3.4 on FF
Canon EF 300/4L - Very sharp and looks really cool - Prefer pop of the Vario-Sonnar 100-300mm but appreciate AF when needed
Canon EF 100-400L IS - Really good stabilisation, but results are soft compared to the Zeiss 100-300mm wide open. Good for 400mm.
Canon EF 35/2 - Actually I like this one! Useful in low light on FF
Tokina 20-35mm II - Fantastic sharp little lens! Nikon 20/4 is sharper and smaller, but the Tokina is more convenient on FF

[William]

Graham, I wish I could accidentally collect EF L lenses...

I am putting off buying AF lenses at the moment because I still have this desire in the back of my head for FF and with it all I'd need would be a few of the cheaper primes, 28/50/135 etc but then the DA limiteds look so nice and are possibly the closest AF lenses in spirit to the proper lenses that we're used to so I wonder..

The Pentax 18-55 WR has been used quite a bit because it handles well and despite never being so sharp as to injure, it gives pretty detailed images with good contrast and colour saturation. It is also so easy, set it to F8 and it'll perform and it has a very versatile range, going to far wider than any primes I currently have. For an AF lens the focus ring is also highly usable.

[stratboy99]

I also find that some of my MF zoom teles could do close focusing compared to AF teles.

[jun]

i can open & clean a manual focus lens and put it back together.

i have not been successful in opening and cleaning THEN putting back the lens and still ahve the autofocus mechanism still working .
[/b]

[Orio]

Manual focus lenses are sexy and they speak of history
Autofocus lenses are not sexy and they speak of trite gossip.

[LucisPictor]

As you all know, I also own some AF lenses.

Here are my experiences:

Sony E-mount:

SEL 2.8/16 = Better than most tests say, actually. Not a top-performer, but there is hardly any alternative (same speed, same size, same price!)
SEL 18-55 OSS = Often blamed as the "crappy kit-lens", but it isn't. It's fast and produces good images, and it's built is much better than e.g. the EF-S 18-55.

Canon EF-S:

Sigma 18-125 OS = Perhaps the best "allround" zoom lens for APS Canon I ever had if we consider all aspects (built, speed, IQ, focal lenght range...). Better than the EF-S 17-85, the old Sigma 17-70, the EF-S 18-135. OK, the EF-S 15-85 is another league but also another price category. (I have not tried the new Sigma 17-70!)

Canon EF:

Sigma EX 1.8/24 = one of my favourites, really and also without a real MF alternative.
Sigma EX 15-30 = I bought and keep it as a fascinating wide-angle lens for my 5D.
Tokina AT-X 2.6-2.8/28-70 = I love this lens, it's by no means perfect, but it's built like a tank and works well.
Tokina AT-X 24-200 = Yes, it has some draw-backs (as you might guess), but on a 5D it's a great holiday walk-around.
Canon EF 1.8/50 II = Crappy built, AF sometimes misses, but generally good IQ. A present from my wife.
Canon EF 75-300 USM II = Better than I expected. Better than most MF tele zooms I have used. I once sold this copy to a friend and bought the exact copy back when he bought an L lens.


Where I see the differences between AF and MF lenses?

AF lenses are more convenient and MF lenses have more "feeling".

BTW, the Sigma EX and Tokina AT-X series lenses almost feel like MF lenses, haptically fantastic and great built.

[Sevo]