Samples: Nikon 85mm + Lens Turbo

Morning All,

So I managed to take my lens turbo outside for its first outing yesterday, and pared it with the Nikon 85mm F1.8. On the Lens Turbo it effectively becomes a 90mm F1.9, so pretty close to it's original design:


Weight of the Lens Turbo and the all metal Nikon 85/1.8D do make the camer a little front heavy

My previous post with the lens turbo and Nikon 50/1.4 got a little mocked for my improvised (bathroom) studio, which is understandable because I didn't really know what I was doing. So I stuck to my more usual style of photos yesterday.

All shot in raw, and pushed through LR5 Beta. Minimal PP done, mainly just white balance and exposure comp. Think I might have cropped one or two, but nothing major. Also, forgive my poor manual focus skills, first time I've ever shot without autofocus.


Shot wide open as light was falling away pretty fast

Some more:

Forgot the F-stop, but probably F1.8 ;-)


Pretty sure F2.8


Stepped down to F2.8 again

Trying to capture Bokeh. Looks nice enough to me, although light spots appear slightly oval, is that strange? Any ideas?


F1.8

And finally, I thought I'd give the low light shot a go, as there have been a number of threads commenting on coma, particularly in the corners.

This is again close to OOC (no cropping) and as I don't really know what I'm meant to be looking for, I'll have to let you guys pixel peep!


Again shot wide open (F1.8) to emphasis any defects

Really nice pictures! I am sorry didn't understand the technical points you were trying to make - newbie here - but the photos are nice

BTW, what's a lens turbo? And interesting to see you were using a Nikon lens with a Sony body. I thought every manufacturer has their own locked-in system?

Edit - I am sorry if I am taking this off-topic.

looking good

> ... the Nikon 85mm F1.8. On the Lens Turbo it effectively becomes a 90mm F1.9

Doesn't the lens effectively become a stop wider as well with a Lens Turbo ? So really more like an f1.3 ?

It'll be 1.3 in light gathering but around 1.9 in depth of field.

EDIT: Actually it might be larger (1.3 like you said) in light gathering and then somewhere around 1.4 or 1.5 in depth of field. I don't actually know the effect of these optical reducers on DoF.

When you put a full-frame lens on an APS-C sensor the field of view is narrowed but the focal length, which is what influences DoF, doesn't change. So a 90mm 1.8 becomes a 135 1.8 for light gathering and 2.7 for DoF.

The shape in the bokeh is determined by the shape the aperture blades form, so they could be slightly askew. There are actually toy lenses that will make a heart shaped bokeh!

A couple more samples from later that day:











Personally I'm happy with the results - and the whole manual focus thing wasn't as daunting as I thought it was going to be (I grew up in the digital + autofocus age!). I do rely on focus peek entirely though, so can't imagine how hard it would have been without it!!

amp101 said:

amp101 wrote:

Really nice pictures! I am sorry didn't understand the technical points you were trying to make - newbie here - but the photos are nice

Click to expand...

Welcome to the forums and thanks for the kind words!

amp101 said:

BTW, what's a lens turbo? And interesting to see you were using a Nikon lens with a Sony body. I thought every manufacturer has their own locked-in system?

Edit - I am sorry if I am taking this off-topic.

Click to expand...

You are correct in that lenses have a fitting designed for a specific mount (eg. Nikon F-mount, Sony A-mount / E-mount...etc). However...

The Sony NEX cameras have such a narrow mounting flange (essentially the distance between the back of the lens and the sensor) that it's been very easy for 3rd party manufacturers to produce cheap 'dumb' adapters fit in between the lens and the camera which effectively allows you to mount another brand onto your Sony E-mount (eg. Canon, Nikon ...etc). I say 'dumb' because these adapters don't convert any of the electronics or focus drive motors, just the physical fit, so essentially the Canon/Nikon/Minolta/Leica lens becomes manual focus only.

That is essentially what this Lens Turbo is, a dumb adapter. The only difference (and hence the price premium) is that it also has a glass element that creates 0.72x factor to the original focal length, which effectively cancelled out the 1.5x crop factor you normally have to apply to when converting a full frame lens to an APS sized sensor. Simple, but effective.

Does that all make sense? Clear as mud? ;-)