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Author Topic: 1938 Aerial Photos  (Read 386390 times)

Ric Gillespie

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Re: 1938 Aerial Photos
« Reply #120 on: June 28, 2013, 05:58:10 PM »

Dave Alan, in post #82, raised the issue of Jeff's planned use  of the 4x5 Negflat carrier to hold the 5x5 negatives.  It would scratch the emulsion off the "4" side" of the 5"x5" negative.   

No doubt Jeff has figured out an alternative, and I wonder if he would mind sharing it with the group.

In a recent email exchange with the Keeper of Photographs in NZ, Jeff wrote:
"I am very cognizant of the absolute requirement to do no harm to the original negatives.  I am bringing the second Besler negative carrier because it is gravity based rather than tension based: While the Besler #8322 may not hold the negative as flat as the Besler Negaflat carrier, the Negaflat has a propensity to nick the off-image negative edges to create tension so we’re probably better off using the #8322."

This is all beyond my pay-grade but I pass it along in the hope that it answers your question.
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Robert John Mills

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Re: 1938 Aerial Photos
« Reply #121 on: June 28, 2013, 11:52:07 PM »

Hi Ric.  I am new to the forum but I am fairly well read with regards to the Earhart mystery. 
I was looking at the 1938 image recently posted (38entire.jpg).  I am curious as to what the light colored anomaly is just north of the seven site.  If you eyeball the 'backside' of the seven for a rough length and go to the northwest along the shore approximately two of these lengths, starting from the top of the seven, you see something light colored, initially what I thought was an arrow pointing to the SE.  I see on the photo that in numerous places there are white specs that are developing or optical imperfections, but they are blobs.  When you look at what I have described, this anomaly has a shape.  Could this be plane wreckage?  There is also another anomaly out on the reef to the SE that looks interesting, smaller than the one previously mentioned.  I know this goes against current thinking (that they landed on the other end of the atoll- which I agree with) but it looks odd to me. 
Great find with the photos in New Zealand.  Keep up the excellent work and best of luck!!!
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Monty Fowler

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Re: 1938 Aerial Photos
« Reply #122 on: June 29, 2013, 11:38:24 AM »

In a recent email exchange with the Keeper of Photographs in NZ, Jeff wrote:
"I am very cognizant of the absolute requirement to do no harm to the original negatives.  I am bringing the second Besler negative carrier because it is gravity based rather than tension based: While the Besler #8322 may not hold the negative as flat as the Besler Negaflat carrier, the Negaflat has a propensity to nick the off-image negative edges to create tension so we’re probably better off using the #8322."

This is all beyond my pay-grade but I pass it along in the hope that it answers your question.

I think this answers any lingering questions about Jeff Glickman's qualifications and methods. My check for the New Zealand trip went out today.

LTM, who knows all about tensions,
Monty Fowler, TIGHAR No. 2189 CER
Ex-TIGHAR member No. 2189 E C R SP, 1998-2016
 
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Charlie Chisholm

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Re: 1938 Aerial Photos
« Reply #123 on: June 29, 2013, 01:14:44 PM »

I was looking at the 1938 image recently posted (38entire.jpg).  I am curious as to what the light colored anomaly is just north of the seven site.  If you eyeball the 'backside' of the seven for a rough length and go to the northwest along the shore approximately two of these lengths, starting from the top of the seven, you see something light colored, initially what I thought was an arrow pointing to the SE.  I see on the photo that in numerous places there are white specs that are developing or optical imperfections, but they are blobs.  When you look at what I have described, this anomaly has a shape.  Could this be plane wreckage?

Some of us think the arrow might be a signal built by AE & FN for aerial searchers.

It is definitely not an airplane wreck.

Rather than repeat everything, see this recent thread http://tighar.org/smf/index.php/topic,1201.0.html

Sorry, it's a little long and contains other topics, but the basic case for the arrow-as-a-signal is there.

The arrow feature is a pet project of mine, and I am eagerly awaiting the hi-res photos.

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Paul Parsons

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Re: 1938 Aerial Photos
« Reply #124 on: June 30, 2013, 09:25:47 AM »

Occasionally contributors will refer to a "light" or "dark" feature in a black and white photograph. But it should be remembered that the spectral sensitivity of black and white films has changed.

For example, the earlier orthochromatic films were sensitive to blue and maybe green light only. Thus features reflecting light at the blue/green end of the spectrum will appear "light", while features reflecting light at the yellow/red end of the spectrum will appear "dark". The later panchromatic films were sensitive to all light, and thus more closely matched the spectral sensitivity of the human eye. The switch from orthochromatic film to panchromatic film seemingly occurred between the 1920s and 1940s.
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Gloria Walker Burger

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Re: 1938 Aerial Photos
« Reply #125 on: June 30, 2013, 12:04:49 PM »

Paul Parsons wrote:
Quote
the earlier orthochromatic films were sensitive to blue and maybe green light only. Thus features reflecting light at the blue/green end of the spectrum will appear "light", while features reflecting light at the yellow/red end of the spectrum will appear "dark". The later panchromatic films were sensitive to all light, and thus more closely matched the spectral sensitivity of the human eye. The switch from orthochromatic film to panchromatic film seemingly occurred between the 1920s and 1940s.

Would that mean that if AE shot a flare in 1937 that was red, it might show up as a black or dark gray dot in a black and white photo? (see post "Small dot in Lambrecht Photo possible flare sent by AE?" under 'General Discussion')
Gloria
TIGHAR #3760
 
« Last Edit: June 30, 2013, 05:03:08 PM by Bruce Thomas »
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Paul Parsons

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Re: 1938 Aerial Photos
« Reply #126 on: June 30, 2013, 12:33:19 PM »

If the black and white film was orthochromatic then yes: red light will not affect the photographic emulsion and will thus appear dark on the resulting print.
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David Alan

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Re: 1938 Aerial Photos
« Reply #127 on: June 30, 2013, 10:18:42 PM »

Paul Parson brings up a good point with regard to the color sensitivities of film and, indirectly, the question of which film stock was used in the newly found aerial photos.  Such information is important for just the reason he stated.
 
I do not know Paul's background in photography but I would argue these films are panchromatic and it is not my intent to step on anyone's toes -I never learned to dance- but there are couple of things I think are worth noting and clarifying.

Even within orthochromatic films of one company there were different sensitivities manufactured, while, generally speaking, the difference in the spectral sensitivities of panchromatic films might only be seen when looking at the emulsions produced by different companies, e.g. Kodak vs. Agfa vs Ilford.
 
I am guessing here but I think the film used in these particular aerials photos was a panchromatic stock.  Some of my reasoning for this is: 1) Ortho films have substantially more emulsion contrast  than pan films - these images appear to be from a lower contrast film; 2) the many tonal values in the sky and clouds would be almost non-existent if reproduced by an ortho film unless a filter (K-2 or eqiv.) were used, but that would be counterproductive for aerial photography since a  K-2 requires a full stop increase in exposure for a film that was likely no faster than 25 ASA, and, if you are photographing islands then there is little need to reproduce the sky correctly; 3) pan films were developed well before 1920 and in wide use by 1930; 4) after looking at color images of the island flora from several sources, the grey tones reproduced in the aerial films seem typical of pan films I have experience with.

With regard to Gloria's question: Yes, ortho films are insensitive to portions of the red spectrum but no, they will not reproduce a red light as a dark area.  If a light is not bright enough or within the range of the film's spectral sensitivity it will not register at all but that is different than registering darker.  I believe Paul was referencing light reflected by an object as opposed to an object being the source of light. 

Also, while I know absolutely nothing of the flare that may have been on AE's last flight --its composition, it's manufacturing, or even its proper use -- I would be more than surprised to find that it would have emitted such a severely limted range of the spectral light that it would not register a density even on an ortho film.  Perhaps someone here can detail the material used in the flare and the resultant spectral wavelength throughout its ignition.
 
And Ric, if you made it this far, will you be releasing any more of the low-res copies of these prints?  And what thought has been given to the release of the digital copies of the films once you and Jeff have returned from NZ?  I'm not trying to stir the pot here, I know this is all under TIGHAR's purview, I'm just hoping to know an answer to the disappearance of AE and FN before I slide underground.  I think these photos and a return to Niku to further explore the anomaly are the best chance of this happening, distracting lawsuits aside.

cheers,
d

Now is the time for all good men.
                                        Pogo
« Last Edit: June 30, 2013, 10:46:43 PM by David Alan »
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Ric Gillespie

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Re: 1938 Aerial Photos
« Reply #128 on: July 01, 2013, 06:51:19 AM »

And Ric, if you made it this far, will you be releasing any more of the low-res copies of these prints?

I've been a bit hesitant to post many of the lo-res copies because I know that doing so is sure to release herds of camels, but here are a few more as examples of the kind of coverage the photos provide.     

  And what thought has been given to the release of the digital copies of the films once you and Jeff have returned from NZ?

Once we have them,  I see no reason not to put hi-res copies of all the photos in a gallery on the TIGHAR website.  Of course, as always, anything we see that looks really interesting will be the subject of a research bulletin.

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Gary Duchesneau

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Re: 1938 Aerial Photos
« Reply #129 on: July 01, 2013, 10:15:49 AM »

Wow, western- shore picture is very interesting....
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Ric Gillespie

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Re: 1938 Aerial Photos
« Reply #130 on: July 01, 2013, 10:19:49 AM »

Wow, western- shore picture is very interesting....

Yeah.  Can't wait to get my hands on that one.
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Nancy Marilyn Gould

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Re: 1938 Aerial Photos
« Reply #131 on: July 01, 2013, 10:22:49 AM »

What is so interesting about it (other than that it looks like it's from the area of interest)?
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Ric Gillespie

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Re: 1938 Aerial Photos
« Reply #132 on: July 01, 2013, 10:24:31 AM »

What is so interesting about it (other than that it looks like it's from the area of interest)?

That's enough for me.
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Gary Duchesneau

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Re: 1938 Aerial Photos
« Reply #133 on: July 01, 2013, 10:49:41 AM »

Nancy, look at the middle area of the picture... On the edge of the reef....
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Nancy Marilyn Gould

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Re: 1938 Aerial Photos
« Reply #134 on: July 01, 2013, 12:28:02 PM »

Sorry, not sure what I'm supposed to see.  I do see a few white dots out in the water.  Not sure if those represent anything significant.  I guess we'll just have to wait until Jeff Glickman gets a chance to do his analysis.
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