From: "Vladimir Galogaza" 
To: "ATM shore" 
Reply-To: "Vladimir Galogaza" 


James,

>I currently 'assume' that these possible errors will have
>limited effect on the final result.

Even in this case, we should know spread of "effect" in  numbers
however small they may be.

> Robo is always measuring FIXED zone
>radiuses, much like the classic method of using a Pin-Stick Foucault test.
It may be fixed, and yet still measured and therefore prone to measuring errors.

In Pin Stick method position of sticks is MEASURED and know together with
certain known measurement error ( mostly and justly neglected with respect
to the overall accuracy of the method).

I remember times when so called flow diagrams were very popular.  I would
appreciate to see such an flow diagram of the roboFoucault  method. That
will enable us (me) to find out exact procedure without being lost in
programming details, although this can be also important in method fault
(bug) finding.

>The digital circle that defines the edge of the mirror in the video, is
also
>THE factor in determining the pixel scale.

On some images I could see that this circle does not coincide with what I
would say is edge.


>I'd "Guess" a zone radius standard deviation (for this
>exercise) must be somewhere around 0.08" (2 pixels) and in reality is
>probably less.

In my measurements on 7 zone data, on zone 4 radius, I could say zone is
determined with 1.4% standard deviation , zone is 70% plus or minus 1%
( If use of the standard deviation for 4 measurements is meaningful at all.
Absolute maximal error would be more apropriate.)

>#1 How much does the Diffraction ring around the edge of the mirror
>effect the apparent diameter of the mirror in the video stream?

Make a photo with mm ( or inch) scale along a measured radius and compare
diffraction ring radius readout from the scale on the focogram,
 with known radius of the mirror. This can also answer
the following question:

>#3 What are the effects of the 'STUFF' between the camera's CCD and >the
Final
>BMP image inside the computer, and how will this effect image scale?

I wrote: "(only James knows to what extent) " Your answer was:
Heck, I don't know!
 But I meant another James, (Burrows)! He knows.

What we are discussing here is independent on if Robo will succeed or fail.
It applies in each case. I understand that in the moment you are primarily
 interested in finding if robo method has systematic fatal bug. And I know
if
it has it will very likely   be "polished out". In that case I am also sure
you
 will polish the method to "1/100 waves". Than this discussion will be
useful.

Regards
Vladimir.

PS
IN my previous post I forgot to ask you to be so kind and send my thanks to
Charly who donated his mirror.

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