Why did I not get sharp focus here? Camera sensor not good enough??

[Easy Rider]

I did not use a tripod, but I did have the camera stabilized on a wooden railing, flat surfaced.

I used F11 as have read Nikon DSLR's go soft due to defraction past f8, but felt (perhaps wrongly that as the distance between camera and far wall with the books was so far away F8 would not be enough) and kept ISO to 1600 which I did no want to go above and felt the 1/ 50 s/speed would be adequate as camera on stable platform.

All in all, not a bad exposure judgement, I feel.

So I had a stable platform, I used F8, spot metering and single point focus using the centre point on my D5300 focused on the far wall.

Again, I believe focussing on the furthest thing I wanted in focus makes sense.

EXIF says my Sigma 17-55 F2.8 EX DC OS HSM was set at 36mm eqvt, so was reasonably wide.

I even added some clarity and contrast in CS6 but am still unhappy with how out of focus or un sharp the far wall is.

My vision was that outside the window you can see the wild branches of the trees. These contrast with the neatly stacked books at straight angles. Also the lights form ceiling hang down like branches.

Books in the library are made for paper, which is made by trees. Wildness of branches, neatness of man made boos and environment You get my point.

Standing from where I took that shot, with your eyes without camera and through the VF it really looks like a nice shot.

I got my composition well here but wanted EVERYTHING in tack clear focus.

I can only assume that

A. I used wrong F-stop or too high ISO - in fact when you zoom in you can see a lot of noise on the books, even though at ISO 1600 the d5300 should not be too bad.

Perhaps I should have gone for base ISO and longer shutter speed?

B. I am not sure if on zoom lenses that wide open is as good as tele end. I have since read that this lens is sharpest at the tele end, which makes sense as more dof.

C. The dynamic range is bigger than my camera's 14 stops

D. You need either basically,

1. A a larger format camera that simply gather more light for a scene as large as this from short to the other end of the library and the width of the walls

2. Artificial light such as speed lights or strobes etc

I honestly thought my D5300 with the Sigma F2.8 DC EX OS HSM should be good enough to get this scene and scenes like it in good clear focus with little noise.

Is it good enough, but my technique was wrong somehow, or are my assumptions regarding A, B, C and D (1 and 2) above correct and the D5300 cannot capture such a large scene with such a large amount of detail in tack sharp focus?

Here are two more images, that while not bad images - are not tack sharp and clean, which is what I want.

I'd like to make the best of my camera and lens without upgrading and am hoping it is down to poor exposure settings, such as aperture and ISO...

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https://www.flickr.com/photos/131361106@N07/sets/72157651211963409/ https://www.flickr.com/photos/131361106@N07/sets/72157654221552079

 

[Janoch]

If you can ignore the 'D800' part, this technical guide may perhaps inspire you?

https://support.nikonusa.com/app/answers/detail/a_id/18103/~/d800-%2F-d800e-technical-guides

 

[baloo_buc]

The small apertures increase DOF and diffraction simultaneously. As everything is a compromise is the photography you have to balance DOF with loss of sharpness due to the diffraction. With 24 MP sensors I would try to keep the aperture above f/8. Usually f/8 gives you ample DOF and the diffraction is still mild.