Quality question about the "old" AIS 50mm f1.4 and f1.8

[Bent Hjarbo]

I have two versions of the 50mm f1.8, short nose and long nose, and a copy of an AIS 50 f1.4.
After all the discussions about the quality of the old MF Nikkors I thought I would see how the fared on my D800, I know this may not be an easy task for the lenses.
My results at the moment is not encouraging as they seem very soft wide open, in a way that I think something is wrong.
I have attached pictures taken with two of the lenses, the f1.4 seems worst.
Any suggestion for what could be wrong, other that using the D800 for this purpose
My choice of testing place may not be the best, but based on suggestions I may do a new round when the weather allows it.

[Akira]

Bednt, what I'm seeing seems to be the images that have different focused points.  So, it may be difficult to compare, although it is not surprising if 50/1.4 wide open would yield the softest result.  The sharpest subject in the image with 50/1.4 wide open seems to be the tree on the far left side.

An Ais 50mm lens (f1.4 or f1.8 but especially f1.4) are, due to its very short focus throw, very tricky to nail the focus, especially between 5m and infinity.

[Bent Hjarbo]

The focus point was in the midle of the picture, not the best place, but I did in order to compare all my old MF lenses. It was the easiest, but maybe I will have to redo the test.
What surprise me is the complete lack of contrast at 1.4, it makes it impossible to use.

[Bjørn Rørslett]

In order to get better comparisons, select a subject that is easier to focus with cetainty. I own various versions of the 50 Nikkors and consider them to be quite good optics in general.

Suggest you bring a couple of these along to the upcoming Crete trip. There we should have time to do some test shots, hopefully. The Df might be a better camera for focusing manual lenses than your D800.

[Bent Hjarbo]

I will bring them to Crete
In the meantime I will try to find a better place to test, I just want to avoid brick walls

[pluton]

At 1200 pixels across, fine determinations are difficult.  It looks to me like all the shots were focused in the center, at what appears to be an "almost-infinity" distance.  Focusing with magnified live view will eliminate the vagaries of eye-focusing and AF if those methods are in question.
Within the limits of the 1200 pixel-across files presented here, it looks to me like your tested 50/1.8 has an issue with centering or mechanical alignment:  the left side is out of focus while the right side and center appear to be sharper.
I have 2 copies of the 50/1.8 Ai "long nose', and my 2 copies perform identically in these kind of tests.  They do not exhibit the asymmetrical distribution of focus that your tested copy does.
Yes, they are low contrast wide open, but wide open is still useful: Wide open can be useful when there is a central subject to be surrounded with a "soft world" look. 
For subjects that demand a more even, across-the-field high definition, I think in terms of at least f/2.8 and really f/4 with these lenses.

[Bent Hjarbo]

Maybe I should use a brick walls just to check the mechanical status of camera and lens

[simsurace]

The 50/1.8 seems badly decentered.
The 50/1.4 shows a mix of aberrations wide open.
But your focus is too far away, basically the entire frame is outside the dof. Please reshoot with the focus on the foreground trees for example. A fairly flat subject is preferable for testing lenses.

[pluton]

Maybe I should use a brick walls just to check the mechanical status of camera and lens

Funny how useful those brick walls...and other wall surfaces...can be.

[Akira]

A brick wall might work, but the lenses without CRC would tend to be sensitive to the focusing distance: the aberration affects in varying manner according to the focusing distance.

So, assessing the lens with a brick wall for the usability of landscapes may not a good idea.  You cannot assess the bokeh quality either.

[pluton]

A brick wall might work, but the lenses without CRC would tend to be sensitive to the focusing distance: the aberration affects in varying manner according to the focusing distance.

So, assessing the lens with a brick wall for the usability of landscapes may not a good idea.  You cannot assess the bokeh quality either.

Yes, the best will always be to test on the actual use intended.

[David H. Hartman]

Why not a large brick wall like the side of a building as apposed to a garden Wall? We on "The Ring of Fire" don't have large brick walls like the side of a building as such buildings fall down when the earth moves.

Seriously a large brick wall is far more useful compared to a poster size chart taped to the wall.

Dave Hartman

My pick many years ago was a 50/1.8 AI over a 50/1.4 AI as I found the f/1.8 was better wide open than the f/1.4 was at f/2.0.

[Bent Hjarbo]

A brick wall might work, but the lenses without CRC would tend to be sensitive to the focusing distance: the aberration affects in varying manner according to the focusing distance.

So, assessing the lens with a brick wall for the usability of landscapes may not a good idea.  You cannot assess the bokeh quality either.

Yes, the best will always be to test on the actual use intended.

The reason for taking the pictures in the park, was actually because I wanted to test in a way I intended to use the lens. As it turns out, I will have to find a large brick wall to test for other faults in the lens, but I will also try to find a better spot for the actual use test.
Thanks for all the suggestions, it has been very helpful I will post some results after I have found the places for testing.

[Erik Lund]

I would say that it is a very difficult framing combined with very limited depth of field in the background,,,, maybe this could work as a very large print but I have a hard time to see what it is you are trying to emphasise with the framing dof etc,,,

[Airy]

My pick many years ago was a 50/1.8 AI over a 50/1.4 AI as I found the f/1.8 was better wide open than the f/1.4 was at f/2.0.

That's not my observation with the short nose version of the 50/1.8, but I have yet to test the long nose version (in my case, an earlier AI).