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Location: UFOUpDatesList.Com > 2007 > Jul > Jul 20

Re: The 1952 Tremonton Utah'Seagulls'Confirmation?

From: Martin Shough <parcellular.nul>
Date: Thu, 19 Jul 2007 17:43:29 +0100
Archived: Fri, 20 Jul 2007 09:32:33 -0400
Subject: Re: The 1952 Tremonton Utah'Seagulls'Confirmation?

>From: David Rudiak <drudiak.nul>
>To: <ufoupdates.nul>
>Date: Wed, 18 Jul 2007 11:17:59 -0700
>Subject: Re: The 1952 Tremonton Utah 'Seagulls'Confirmation?

>>From: Michael Tarbell <mtarbell.nul>
>>To: ufoupdates.nul
>>Date: Wed, 18 Jul 2007 06:40:08 -0600
>>Subject: Re: The 1952 Tremonton Utah 'Seagulls' Confirmation?

>>Hartmann's suggestion that the objects are "unresolved" seems at
>>odds with Baker's observation (same reference as above) that,
>>based on microscopic examination of the film, the camera was
>>well-focused: "...the edges of the images are sharp and clear
>>on many of the properly exposed frames".

>If the camera was in sharp focus, "unresolved" could simply mean
>'no detail', as might be expected from something like a glowing
>disc with no appendages.

Hartmann believed they are not resolved for two reasons: 1) a
gull modelled as an 8 inch circle with a 2-foot wingspan at a
just-possible 2000 ft range would be "at the margin of
resolvability", which he takes to be 1 - 3 arc mins; 2) most or
all of the image size was assumed to be "flaring" due to the
brightness. In other words, the birds would, he suggests, be
virtually imperceptible except for halation, pointing out that
when the objects occasionally fade out completely there is no
dark shape or dot visible. (If the objects "fade out completely"
I su[ppose this means their brightness equals the background sky
brightness, which presumably is quite bright on a cloudless day
near noon in July in the desert.)

But he is using a figure for the resolving power of the human
eye (which is slightly smaller than the conventionally-cited
3.75 arcmin but more comparable to the limits you suggest
below). Surely considered as a lens system the eye is a much
poorer resolver than a good camera lens because resolution is
inversely proportional to aperture - other factors being equal
(so neglecting focus and film emulsion characteristics etc)?
What is the theoretical resolution of a Bell & Howell Automaster
"3 inch f.1 telephoto lens?

>However, "seagulls" would very definitely show details if the
>angular size of the image is great enough. Wings in particular
>will clearly stick out and wing flapping is very visible. This
>brings us to the next point below.

The question is whether fluctuations due to flapping appear on
the film. The Navy said no, Robertson said yes, Baker seemed to
think on balance probably no, Hartmann thought yes. So there are
fluctuations, the disagreement is about their magnitude and
frequency. The Navy measured a constant brightness through what
was calculated to be 60 degs of arc (presumablly based on
Newhouse's statement) and concluded that absence of blinking
meant self-luminosity. The Robertson Panel pointed out that a
hemisperical reflector could easily maintain a constant
reflection through 60 degs without blinking. so could still be
birds.  If you are free to optimally orient a hemisphere without
wings attached this may be true, but I'm suspicious that this
misses the point.


>The scientific twits on the Robertson Panel should have gotten
>outside their laboratories more often to view flocks of birds
>way off the distance. Even as they move away and they are barely
>more than dots, the wing flapping is still easily visible. Even
>birds riding thermals with minimal flapping should still have
>visible wings. Baker's film analysis indicates that at least
>some of the objects were still very resolvable "dots" and
>details such as wings and flapping should have been apparent
>both by eye and on film.

They did view a film of seagulls for comparison, and I seem to
recall that one of them - was it Thornton Page? - referred to
having seen seagulls that looked similar. Hartmann also went to
the area of Tremonton in August 1968 and claimed to have watched
groups of bright gulls looking very much like the film. On the
other hand Baker said he had never seen such gulls. But really
we still need to see Brad Sparks' experiment carried out.

Martin Shough

Listen to 'Strange Days... Indeed' - The PodCast



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