Project 1: The distorting lens – Ex. 2.7

Ex 2.7

Some issues?

I definitely agree with the brief here: this may appear easy but it is much harder than it seems to get that depth. I think I might have had some issues with camera shake too, I believe that was caused by the shutter (even if I have the E-M10 set to use an electronic shutter below 1/250 to reduce that shake?). Although that could easily have been the wind; Or was it some imperceptibly subtle camera movement on the wall I had placed it on?
I find it hard to accept that it could actually be the aperture at F/22 (as it seems to be as both zoom lenses show a clear reduction in clarity when viewed close up). I always thought a smaller aperture equals more clarity throughout the whole frame and not just centrally? So I can only assume this slight blurring was caused by something else?
What’s going on?


The F/3.5 is the clearest. How’s that?
The F/22 is blurry.
Maybe these cheap(ish) zooms have these limitations in terms of quality?
I’d like to give this a go with some high-end glass, see if it’s my sensor and/or the image processing unit that creates this issue. Who knows, may actually be a case of bad luck?
We’ll see, definitely something I need to invest some time in (as well as possibly investing some dosh in to buying a decent tripod?).


And again, the F/22 version is blurrier! What am I missing?
So I had a go at 42mm too, just to see if there was any difference:

And once again, the smaller aperture appears (and is) blurrier than the rest.
I’ve looked around a few blogs and sites and haven’t found anything on this apparent inversion of the smaller F-stop being sharper rule… So, what is going on here?

Must be the longer shutter speed; or did the suspect wall that I had the camera on also affect the final result?
Just had another thought: could it be the in body image stabilization (IBIS)?
Maybe when the camera isn’t moving it needs to be turned off?
I may have found something about this on Wikipedia, although, I have to say, I found it quite tricky to understand (and not for the way the article is written which is really thorough, but rather my own incompetence within this very specialised field of optical image stabilization!).
The section on ‘sensor shift’ technology part seemed relevant especially when they start talking about using long focal length zooms with slower shutter speeds. They say:
The required sensor movement (both speed and range) increase with the focal length of the lens being used, making sensor-shift technology less suited for very long telephoto lenses, especially when using slower shutter speeds [my underlining] because the available motion range of the sensor quickly becomes insufficient to cope with the increasing image displacement.”
So, it could well be that, although, I repeat: this is just out of my reach at this stage with my photography, but does seem pertinent and very interesting nonetheless.
Patience is a virtue, and all that!


 

References

Wikipedia, Image Stabilization, Dec 2015, [online]; Available at: https://en.wikipedia.org/wiki/Image_stabilization  [Accessed 30/03/2016]


Contact sheets

Ex. 2.7 CS 2

 

 

 

 

 

 

 

 

 

 

 

 

 

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3 thoughts on “Project 1: The distorting lens – Ex. 2.7

  1. Kevin, could your problem at the f/22 end be down to diffraction? With a smallish sensor like your (our) Four-Thirds, there is a sweet spot at about f/11 between reduced depth of field at one end of the aperture range and diffraction at the other.

    Liked by 1 person

    1. Chas, thanks for the comment!
      Yep, you’re right (my tutor said that too).
      I haven’t looked at it since though – but defo something to bear in mind for the future.
      Cheers,
      Kev

      Like

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