I own a Nikon D5300 body, but wish to upgrade to a Pro FX body in future (not any time soon).

Between AF Nikkor 50mm f/1.8D and AF-S NIKKOR 50MM F/1.8G, I prefer to buy the former, but at the same time, skeptical about my purchase decision.

The reasons I'd like to choose the former are:

  • The former is a lot cheaper
  • I don't want to spend for what I won't need if I upgrade. I believe all Pro FX bodies have AF motor built inside the body. Hence, SWM in 'AF-S' lens is redundant
  • The former is a bit lighter (~30gms)
  • The former is dimensionally a bit smaller
  • The optical performance, especially the Bokeh are comparable

The reasons I hesitate before making the purchase are:

  • The later is said to have a better build quality (How better is the later compared to the former?)
  • The former has an aperture ring which I am not at all familiar with (Is there any drawback of having an aperture ring apart from making the look of the lens messy?)
  • The focus ring of the former turns when you focus. You can't touch it without disabling autofocus first

Can anybody please clarify my doubts? Apart from the points I have highlighted, is there any other major/minor concern which I have failed to take care of?


2 Answers 2


I think you forgot one really basic thing. Image quality. You may want a side-by-side comparison of the much older D design to the digital-era G design on a full-frame camera, such as this one on the-digital-picture.com, where the two lenses are tested on a D3x. In that comparison, mousing over the test chart crops will switch between the two test setups. If you plan on using the lens wide open at f/1.8, there's kind of no contest.

The biggest thing to understand isn't just the features and reputations. But the fact that the 50/1.8G design came out in 2011. The 50/1.8D design dates from 2002, but its optics are unchanged from the non-D 50/1.8, which came out in 1986. They learned a lot about improving lens designs in the intervening 25 years, and digital shooters are far more critical than film shooters were. Hence the glass update.

  • \$\begingroup\$ For the digital-picture link, is it that the image which is automatically loaded is shoot by 'G' version and the image which is loaded if I hover the mouse pointer is shoot by 'D' version? \$\endgroup\$
    – sherlock
    Commented Jun 16, 2016 at 0:08
  • \$\begingroup\$ @Holmes.Sherlock Yes. The arrow at the top tells you which one you're looking at. \$\endgroup\$
    – inkista
    Commented Jun 16, 2016 at 0:20
  • \$\begingroup\$ If that is so, I'm going to accept your answer as the accepted one. I just wonder why the guy who wrote the article in my original post claimed that there is only a slight difference in optical quality between these two versions. At F/1.8 (which I will be most probably using), certainly there is no contest. \$\endgroup\$
    – sherlock
    Commented Jun 16, 2016 at 0:45
  • 1
    \$\begingroup\$ @Holmes.Sherlock, depends on which tests you see, what numbers you interpret, and how you plan to use the lens. If you look at the f/8 results, you'd go the other way. And different testers use different methods and different gear and can get different results. Crop/full frame with the same lens often tend to look quite different, too. It's not like crop sees the FF corner performance. This is why it's good to read a lot of different reviews and look at a lot of different test results. And to keep your personal usage patterns in mind. \$\endgroup\$
    – inkista
    Commented Jun 16, 2016 at 1:01
  • \$\begingroup\$ Yes, I can see visible improvement in mid-range in 'D' than 'G' at f/8, exactly the other way round. Thanks por pointing that out, too. \$\endgroup\$
    – sherlock
    Commented Jun 16, 2016 at 1:07

"...all Pro FX bodies have AF motor built inside the body. Hence, SWM in 'AF-S' lens is redundant."

Not necessarily. The performance of camera based focus motors and lens based focus motors is far from identical. SWM lenses tend to focus faster and more quietly than their non-SWM counterparts. Add the mechanical interface between the body and lens and the noise gets even louder. Newer SWM lenses when used with newer Nikon bodies also tend to focus more accurately as the lens confirms more positively to the camera the exact amount of focus element movement actually effected via use of a focus position sensor.

Regarding optical performance (hint: there's a difference), please see Do Nikon AF-S lenses perform better than AF lenses?

See also: What's the difference between using a 50mm f/1.8G and a 50mm f/1.8D with a Nikon D80?

  • 1
    \$\begingroup\$ I don't know if it's true of the current FX bodies, but at one time the performance of the AF motors varied quite a bit in the product line, too. \$\endgroup\$ Commented Jun 15, 2016 at 22:44
  • \$\begingroup\$ Thanks for bringing in the issue of time difference in focusing with SWM vs. in-body motor. Upvoted. \$\endgroup\$
    – sherlock
    Commented Jun 16, 2016 at 0:10

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