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800E with 85mm f1.8

vjbelle

Well-known member
I finally got my 800E from a local dealer..... the absolute last time I ever pre-order anything from B&H:eek:!! He talked me into trying the new 85mm 1.8. I still can't get over how sharp this lens is. Wide open it is really sharp..... not as sharp as stopped down even one stop but still really sharp. More importantly to me is that wide open it is dead even from corner to corner and side/top to side/top - no decentering whatsover. I check every lens I buy and have sent many back including Schneider Digitars..... this is the first time I have seen a consumer grade lens that is this perfect. Maybe I got the best of the lot but I would really encourage anyone looking at spending $1700.00 (which I could easily do) on the f1.4 to give this new f1.8 a test ride:thumbup:. I'm just absolutely blown away!!

Victor
 

drb

New member
I just started testing my 85 f1.8 and it does seem pretty impressive for the price. I'm finding it's sharpest at f4.0. I did find one scene where it generated some noticeable CA from f1.8-2.8. I've done some side by sides with a new 85mm PC-E and the PC-E has slightly better contrast but seems slightly softer at the extreme corners/edges (no shift and shooting @ f8).
 

BJNY

Member
....I still can't get over how sharp this lens is. Wide open it is really sharp..... not as sharp as stopped down even one stop but still really sharp. More importantly to me is that wide open it is dead even from corner to corner and side/top to side/top - no decentering whatsover. I check every lens I buy and have sent many back including Schneider Digitars..... this is the first time I have seen a consumer grade lens that is this perfect....
Victor
May I know how you go about testing lenses for centering, etc.?

Could you post some examples, especially showing how decentered lens looks?
 
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Jack

Sr. Administrator
Staff member
May I know how you go about testing lenses for centering, etc.?
Simple answer is you're looking for asymmetry in the way image detail falls off around the center; it should be symmetric and evenly distributed with no one area significantly softer or sharper than it's compliment across the center point.

You can shoot a relatively flat surface with texture like a wall and then compare the edges concentrically out from the center. All points along any "circle" should look the same. If the lens has significant curvature, you may need to focus beyond the wall at the center to have enough image detail to determine this at the outer edges.

I tend to use a casual 3-D target most of the time -- a lawn with a fence and hedge behind it. Here you can pretty easily spot side-side decentering as the image looks basically like the lens used was a TS lens that was swung. It has the advantage of immediately determining how severe the curvature is, but the disadvantage is it's only a cursory centering test.

(*There are multiple factors that can affect centeration -- where the optical axis of a lens element is in line with the mechanical axis of the lens. The most common is actually a poorly ground element, also common is an element cocked or shifted in its mounting cup. In a perfect system, an image would not change as you rotated an element completely in its mounting cup. As re Nikon, it is my belief the newer "G" lenses are showing optical superiority not because of better coatings, but more likely more care during production and assembly than earlier versions.)
 

D&A

Well-known member
It should also be noted when discussing centering/decentering of lens element(s) in a given lens, that generally speaking, achieving perfect centering of lens elements is much more difficult in wide or ultra wide angle lenses or wide angle zooms as opposed to a telephoto lens/zoom. This is simply due to the smaller size and surface area of the elements themselves in a wide angle lens, not to mention the sheer number of elements used and needed to be aligned and centered relative to one another in a wide angle vs. all these factors in a telephoto lens. This is of course a over-simplfied explanation. There are exceptions of course but generally, one is apt to find far more near perfectly centered telephoto lens samples of a given lens as opposed to different samples of a given wide/ultra wide angle lens or zoom. So it's not too surprising with decent QC control, to find most samples of the new 85mm f1.4 G lens with near perfect centering. The same cannot be said of some of the ultra wide angle lenses and zooms, even the top tier ones.

Dave (D&A)
 

vjbelle

Well-known member
May I know how you go about testing lenses for centering, etc.?

Could you post some examples, especially showing how decentered lens looks?
I am not in town at the moment but to answer your question I usually shoot a lens chart and check from center to sides and corners. The chart is on a level surface and the camera is leveled vertically. The chart has lines running horizontally which allows me to check whether or not I am perpendicular to it which is important. Its easy to tell if a lens is out of alignment as there will be a bias towards one side/top,bottom. This is just one method of testing - there are many as Jack pointed out.

Victor
 

kuau

Workshop Member
Another lens which I use all the time with my D800/E is the Voigtlander 90mm f/3.5 SL LL APO-Lanthar it's MF but it is extremely sharp corner to corner.
 

Pingang

New member
I am not sure you can say this lens is consumer grade, it is well made and although a little light to my taste, the lens is every bit a professional lens except you probably don't want to use it in heavy rain.

BR,
Pingang
 
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