Re: Converging lenses (was: Window reversal); D|s-TortiO|\|s

[P3D Gabriel Jacob <jacob@xxxxxxxxxxxxxx>]

>> That is very true, and a little bit of keystoning is not objectionable.
>
>Some keystoning is not objectionable, but keystoning is forbidden
>territory?

Yes, that's true. I sais not objectionable, I didn't say acceptable.
Most people would rather live without it. It is a consequence of
trying to match the windows or image in the windows. Other than that,
no one introduces keystone because they want to.  

>Some people telling how *terrible* beamsplitters are like
>to mention that it has *keystoning* (and therefore is horrible) but 
>in many images (when remounting for non-splitter-viewers) you can 
>barely tell if it's  there (if at all).  Or at least that's been
>my experience with my beamsplitter.  I've been making dupes which
>I then split and put into 4-perf "realist-format" mounts.

Mike, I have a beamsplitter also, and think it's great for it's limited
purpose. But don't get me wrong, I think Loreo's, Realists, FEDs, twinned
cameras, etc. are all limited purpose cameras also! They all have
advantages and disadvantages and there is no perfect camera out there
yet. Not even the RBT cause I can't afford it! :-( But this is another
story. Back to distortions.

> I'm pretty sure there is alot of ways that would justify taking a picture
>> of a tree, by using the varied distortions of 3D or 2D cameras, such as
>> lighting, focal length, etc. without ruining the image. No one is saying
>
>I'm interested in those justifications.

To emphasize certain aspects of the image. This is distorting but as I
said there is distortions and distortion faults. There is no justification
to introduce faults in an image (and keep them!), other than purely
artistic reasons. Now if reasons such as the ones John R. or Larry B.
suggested, this sounds like a valid arguement.  
 
  Note that taking a pristine 
>photograph of a tree for the purpose of showing what a tree looks like 
>is an "artistic justification". One portion of painting styles is, 
>for instance, "realism" (or some such term).

Yea, this is an interesting concept, but as I said, (not in these exact
words) I don't want to get sucked in this black hole, of what constitutes
art.

>Are you saying that your rendition of a ghost is more realistic and 
>therefore more valid than a keystoned one?  What if I claimed that
>ghosts look keystoned and that yours is gross distortion with
>the keystoned look left out?

Hey, who says it was a rendition. ;-) Second of all, ghosts are
translucent and have no keystoning properties. ;-) Seriously 
though, with that kind of logic, then I can claim any mistakes
I make, to my interpretation of how a ghost should look!

>I don't mean to go down the dead-end path of using "artistic" as a 
>blanket justification argument, however, I also don't think that using 
>artistic-ness as a blanket anti-argument is valid either.  Because *any* 
>image is an artistic rendition, it can be rejected by just saying 
>"that's artistic and doesn't count".

Yea we sure don't want to go down that path, cause we'll both go down! ;-)
As I said, an artist or otherwise has at their disposable a multitude
of ways to distort or create new realities without resorting to introducing
errors in an image. Errors don't work in reality or otherwise. You can
produce images with the distortion faults for sure, but don't expect it
to become mainstream.  

>I think keystoning can be used and NOT be painful to the viewer. This
>has been demonstrated with my beamsplitter experiments.  This isn't
>to justify keystoning as a standard thing to do -- but that it can be
>done without any compelling justification NOT to do it.

It can be done and not be painful to the viewer. It can be done to a
degree, if the ends justify the means, for reasons already discussed.
In the beamsplitter case, it is "done" and then "undone". Your mixing
up the crux of the discussion. Why introduce it and keep it? It's not
done with the beamsplitter, is it? 

>So the answer to "why" is "why not?".

First of all even in small degrees, you have to understand that it is
not wanted. Second, even if there is no pain, long term it detracts in
the enjoyment of the stereo viewing of any realistic or figment of
your imagination creations. Ask why they sell $30 binoculars and $300
ones! Long term, your eyes get tired soon enough and you won't know 
why. Third, to answer your question, as to why not, cause it is a
distortion fault not a distortion. I am not sure if you grasped that
concept.

Gabriel, take 112.



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