Friday, June 28, 2013

Comparing the Nikon 85mm f/1.4 and f/1.8 G lenses
a hands on review 


The two fast aperture f/1.4 and f/1.8 85mm G lenses are usually rated as the best lenses made by Nikon. I was curious to know if one was any better than the other in terms of image quality. After all, the f/1.8 G version at $496 costs less than one third the price of the f/1.4 ($1650). Is 2/3 of a stop worth that?  Is the build quality that much different? What about the resolution?


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I have been shooting with the 85mm f/1.4 ever since it was introduced.  It is a perfect focal length for a portraits, and I use it mostly for that. I rarely use it wide open for a portrait.  At f/1.4 the depth of field is so shallow that if I focus on an eyelash, the pupil of the eye will be out of focus. Rarely do I use the 85mm at its maximum aperture. For portraits like the samples shown here I tend to stop it down around f/2 give or take one third of a stop. 

I prefer to use this lens for informal portraits where I want the face to be mostly sharp and the background not to interfere by being completely out of focus. My favorite lenses for accomplishing that effect are a fast 85mm or either of the defocus Nikkors (105 or 135mm).


Side by side, the two lenses do not appear that different in size. It isn't until you compare the front lens elements that you really notice the difference.

The f/1.4 model weighs in at 1.45lb (660g) compared to .78lb (350g) for the f.1.8. The f/1.4 takes 77mm filters, has a 3.4"(8.64cm) diameter and is 3.3" (8.38cm) long compared to the f/1.8 model with a 67mm filter size, 3.1" (7.87cm) diameter, and 2.9" (7.37cm) length. The minimum focus distance on the f/1.4 is a tad longer at 3' (91.44 cm) compared with 2.62' (80cm) for the f/1.8.

Both lenses have auto and manual focus modes with manual override. The biggest difference between the two is in the number of diaphragm blades. The f/1.4 has 9 and presents a round opening, while the f/1.8 has 7 and is not quite as round. 

These lenses shine when used for situational portraiture by creating a very soft, out of focus flattering background while keeping the face ultra sharp.


In my sharpness tests I found these lenses to be equal at all apertures. They are very sharp with only a slight softening in the corners when used wide open. Their fast aperture aids in speedy focusing. When I do serious beauty portraiture I rely on the 105mm micro Nikkor lens, but for a more casual, natural look, often shot in available light, I prefer a fast aperture 85mm lens. If you are like me and prefer to use them stopped down a bit to around f/2.2 then the f/1.8 model should work just fine. 




Conclusion:

Both of these lenses are very highly rated for sharpness. After putting both of them through their paces for awhile, I can see why.  For all practical purposes they are pretty much neck and neck. If you need the extra 2/3 of an f/stop and the extra bulk and weight -- not to mention cost -- is not a deal breaker, then get the f/1.4. Otherwise, you can't go wrong with the smaller, cheaper, lighter f/1.8 -- plus it's much easier to tuck into your gadget bag, and I'm sure you can find some other gear to buy with the $1000 you'll save.

After putting the f/1.8 through its paces in our studio recently, all of us who tried it really fell in love with it as a first choice. It focuses quickly and very accurately, has minimal distortion, and its size has a comfortable feel. The two photos below, taken under studio circumstances that we know always cause us problems with focus and color fringing, convinced us that the f/1.8 model is an exceptional piece of glass, definitely the best I have ever seen in its class.  I know I will be reaching for it as my first lens choice in the future.

This is a studio situation I do a lot where the illumination comes only from the two north facing windows you see in the background. It is very tough for any lens, and we usually only use our fastest lenses here because the light is so dim and the backlighting so intense. Whenever a subject is placed directly in front of one of the windows we always have a lot of color fringing to deal with.  This photo was taken with the f/1.8 lens. It had very minimal fringing and it was tack sharp -- the best performance of any lens we have ever used in this situation.

After being impressed with the results of the photo above this one, I decided to push the limits a bit and lit the model from behind with both a window light and a tungsten shining directly into her hair to emphasize its redness. This is the photo with the f/1.8 lens before any retouching. 

1 comment :

  1. u said the 105 for serious job...so i'd love to choose the 105 then

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