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Can we corroborate the stride length seen in the film with the length measured onesite?


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SweatyYeti

Btw, one detail in Green's measurement diagram which supports the widths of trees TC-1 and TC-2 as being 8"....(to his eye)….is the relative sizes of the circles he drew, in his diagram...

 

John-Green-Filmsite-Measurement-Diagram1

 

Notice how the 'Big Tree' is drawn with the largest circle....the two "small trees" on either side of it are the smallest circles....the tree marked as 12" is the next largest circle, after the 'Big Tree'...and TC-1 and TC-2 are drawn slightly smaller....(consistent with a diameter smaller than 12").

Edited by SweatyYeti
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Bill

Twist:

 

When a round or cylindrical object (like a tree trunk) is photographed, there is a potential for a margin of error calculating the diameter of the tree, but the margin varies inversely with the distance the camera was from the tree. In other words, the further you are away, the less margin of error you have. An 8 inch diameter tree seen from 100+ feet has no measurable margin of error.

 

Rather, the margin of error is in the film grain width compared to the real measured diameter, because the true optical side of the tree could fall between film grains, and seem less or more in diameter than actual measures.

 

So you need to take the rated grain resolution of Kodachrome II film, and then measure the tree width as a real world measurement across the film image, based on 16mm film specifications. I don't have the numbers offhand to do it now,, but that is the margin of error any research effort should be concerned with. 

 

So the process is to measure the actual aperture width of Roger's K-100 camera, in millimeters, and divide that by the percentage of aperture width the tree measures (example, if the scan aperture width is 3000 pixels, and the tree width is 30 pixels, then the tree is 1 100th of the true film/camera aperture width (which I believe is in the area of about 10.7mm (note: estimated for illustration) If that estimate were correct, the tree would be 0.107mm wide on film. Then you compare line pairs per millimeter to see how the resolution compares to the tree width known from physical measurements. A margin of error can be calculated from that.

 

Bill

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Twist

Thanks for the answers, both of you.

 

@Bill   Is there a reasonable degree of accuracy in measuring things such as Patty's height, stride or foot length given the quality and known facts of the film/camera/distances?    How much stock should a layperson place on PGF estimates???

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Bill

As a generalization, measures of Patty can usually be considered accurate to within about 1/2 inch, based on the film resolution and her average size in the film.

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Redbone
2 hours ago, SweatyYeti said:

 

There isn't anything to compensate, or adjust for, Twist....in equating a pixel measurement to a tree's diameter, as seen in a 2D image....since the tree's diameter/width is a dimension which runs essentially in a straight line through the center of the tree...

 

Diameter-Circumference-Diagram1.jpg

 

 

We don't need to adjust for the rounded shape of the tree. That dimension is the tree's circumference

 

There is some potential 'degree of error', though....in 'eyeballing' a tree's width, when holding a rigid ruler up to the tree....(as John Green must have done, in measuring TC-1's width.) Redbone's experiment has shown that potential for error.

 

I have tried making the same type of measurement...and got the same result that Redbone did. In transferring the numbers on a ruler to the edges of an 8" round plastic tube....I under-estimated the tube's actual width.

I keep a flexible sewing tape measure in my backpack, in case the need to 'accurately' measure a tree comes up.

 

I don't know how this fits into the present conversation, but Chris Murphy has some diagrams in "Bits and Pieces" #23.

See it here. https://www.sasquatchcanada.com/uploads/9/4/5/1/945132/issue_no_23_pdf.pdf

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Backdoc
2 hours ago, Bill said:

As a generalization, measures of Patty can usually be considered accurate to within about 1/2 inch, based on the film resolution and her average size in the film.


I saw a hardline “skeptic” on one of these Bigfoot shows saying words to the effect of “the image of the PGF walking subject takes up just a tiny portion on that tiny film cell which itself is already really tiny.  You can’t tell much detail on a figure that small”
 

 

any truth to this?

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Bill

Do you see any actual numbers or facts in that skeptic's statement? I don't. Lacking that, the remark is just a bluff.

 

The proper way to approach this matter is the way Jeff Meldrum and I did in the RHI paper on "Image Integrity of the PGF". There, the level of detail in relation to Patty's size in the film is evaluated with facts, and specific numbers. 

 

Bill

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SweatyYeti
20 hours ago, Redbone said:

I keep a flexible sewing tape measure in my backpack, in case the need to 'accurately' measure a tree comes up.

 

 

That's what Steven Streufert and crew used, for measuring the width of the 'Big Tree', at the filmsite….back in 2012...

 

Big-Tree-Circumference-2012.jpg

 

 

They measured the tree's circumference....and from that, derived it's diameter.  22' 02" divided by 'Pi' equals a diameter of 7 feet....(almost exactly.)

 

 

Quote

I don't know how this fits into the present conversation, but Chris Murphy has some diagrams in "Bits and Pieces" #23.

See it here. https://www.sasquatchcanada.com/uploads/9/4/5/1/945132/issue_no_23_pdf.pdf

 

Thanks for posting that link to another one of Murphy's publications, Redbone....though, it contains more of his analytical mistakes.

 

On pages 1 and 2 he incorrectly asserts that the 'DTC' for Patty at F352 was "151 feet". The fact of the matter is....that great of a distance from the camera is impossible....(based on several details seen in the film images).

 

The true 'DTC' was somewhere in the range of 105' to 120'.

 

Gigantofootecus has determined a distance of 118'....using the length of Patty's arm as  a ruler. I think that that distance is about the furthest she could have been from the camera. I think the most likely range, for DTC, is 110 - 115' feet.

 

With regards to Rene Dahinden's determination of the 'DTC' being 102'....in analyzing his method of making that determination....I think I have found one source of error, in his analysis. He used a slightly cropped image of F352...rather than using a true 'Full Frame' image...and hence....short-changed Roger's distance from the 'Main Log'. 

I'll post much more on that, at some point. 

 

Back to Murphy's Mistakes.....on page 5....he made this error.....(he states that the 'Forked Tree' was the source of the first shadow seen crossing Patty's back)...

 

 

 

sweati-MurphyMistake-No.200B.jpg

 

Chris' Physical Model of the filmsite helps to show how the shadow on Patty's back could not possibly have been from the Forked tree...(it was too far back on the sandbar, to be the source of the shadow)...

 

sweaty-Murphy-Physical-FilmsiteModel1D.jpg

 

The lighting Chris used for that picture of his model is closely simulating the direction the sunlight was coming from, in the PGF. 

 

The shadows of trees TC-1 and TC-2 are running close beside each other....(in both the model, and in the film).

 

In fact, the distance between the trees' shadows is just about equal to Patty's 'shoulder width'. And that distance is in the order of 25". The forked tree could not possibly have been casting a shadow which ran only 25" behind tree TC-2.

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SWWASAS

Just the mention of pixels raise a red flag with me.      Film does not have pixels, only digital pictures do.     So digital images which have been created by some sort of scanning process conversion of the film to pixels and those pixels are being used to measure objects?     That conversion has to have introduced some error factor at the pixel level since there is some averaging going on when each bit of film image is converted to pixels.  How much of an error, I don't know, but I would guess something in the neighborhood of 5%   If the error is anything close to that an estimate of Patties height being within 1/2  inch is very questionable.  

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Bill

The issue of pixels and film grain is reasonable to be concerned with. 16mm film is usually scanned at 2K or less, and the film grain margin of error can be increased by the underscan. I always scanned PGF copies at 4K, so I was overscanning, and captured the actual grain structure in the scan (I even used the grain pattern as a focusing guide when setting up the camera), so 100% of the film detail was correctly captured, and no error was introduced.

 

But one must consider the scan scaling to know if a margin of error is introduced by the scan process. If it was underscanned (usually done to make a cleaner picture without apparent grain) at 2K or less, then the margin of error is compounded.

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SweatyYeti
6 hours ago, SWWASAS said:

Just the mention of pixels raise a red flag with me.      Film does not have pixels, only digital pictures do.     So digital images which have been created by some sort of scanning process conversion of the film to pixels and those pixels are being used to measure objects?     That conversion has to have introduced some error factor at the pixel level since there is some averaging going on when each bit of film image is converted to pixels.  How much of an error, I don't know, but I would guess something in the neighborhood of 5%   If the error is anything close to that an estimate of Patties height being within 1/2 inch is very questionable.  

 

We don't need to know Patty's height within a small range of only  an inch, or two, SWW.  

 

What needs to be determined, and proven...is whether Patty's 'walking height' was 7' 3"....or a much shorter height, in the 6-foot range.

 

 

There have been several published "findings", by various researchers, over the years.....proposing…..(and even "Proving")…..that Patty was a monstrous 7 + foot tall, in her crouched-down posture.....(which would equate to a true full standing height of over 8 feet).

 

Jeff Glickman "found" Patty's height to be in the Monstrous range....as did Chris Murphy....Bill Munns...(though, he has retracted it...after the damage had been done, via a National Geographic TV Doc)....and most recently....Thinker Thunker...

 

 

Tinker-Tunker-Patty-Monsta-Height1.jpg

 

 

Interestingly, I was able to "prove" that Jim McClarin is, or at least was, for a short period of time....also in the 9-10 foot tall range....by using the exact same tree scaling that Thinka Thunka used...

 

 

sweati1-Tinker-Tunker-Jim-Mc-Clarin-Monsta-Height1.jpg

 

 

So, the problem here is.....the notion that the PGF subject was well over 7 feet in height has gotten into the realm of the general public...and, it is a false notion....that needs to be corrected.   

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NCBFr

I spent a bunch of time studying this using her exposed foot and the size of the foot prints as the reference and came to the conclusion she was in the 6'9" range +/- a couple of inches.  It was a pretty involved spreadsheet that included a lot of high school trig to get the various body angles right so I would not stake my life on it but it was a fun exercise. 

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SweatyYeti
18 hours ago, NCBFr said:

I spent a bunch of time studying this using her exposed foot and the size of the foot prints as the reference and came to the conclusion she was in the 6'9" range +/- a couple of inches.  It was a pretty involved spreadsheet that included a lot of high school trig to get the various body angles right so I would not stake my life on it but it was a fun exercise. 

 

Very interesting, NCBFr.  :)   If you're able to post your work, I'd be interested in seeing it. 

 

It sounds like your height figure of about 6' 9" is referring to her true, full standing height....(since your analysis includes her various 'body angles').

 

If so, that height is not too different from what my latest thinking is, on Patty's height. A 6' 9"  'standing height' would equate to about a 6' 2" 'walking height'....(as she is seen in the film).

 

I think her 'WH' was probably a little shorter than that...perhaps by as much as 5".  

 

 

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NCBFr

I posted V1 of it a few years ago if you have the search skills to find it.  I tried and failed so clearly I am not up to the task.  I will work on posting V2  but it may be a while as I will want to review it one more time to check for stupid errors.  Will get my HS daughter to check the math.  Here are the pics and lines I used to calculate the final dimension.  The tricky part is understanding it is a 2D pic of a 3D object so twist in the Z axis which is unknown but can be estimated will impact the final height dimension by upwards of 6 inches.  While the lines may look crude, they are based on real world anatomy as far as I could determine.  Hope this helps.

 

3rd edit lol - That is a huge thumb.  Will add calculating its length to the to list as it appears way beyond human range to the visual eye.

 

image.thumb.png.84da40c10ca00ae5283069269d1d6752.png

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Are you sure that's her thumb and not part of the background? I feel like, if that was her thumb, someone would have noticed and pointed it out by now. I've never seen it mentioned before. Look at the first two panels on your image; whatever that is stays at the exact same angle even though the rest of the arm and hand are moving. 

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