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Aaaaaaaaaaaaaaaargh! 5th Dec 2021 13:35

​​​​​​​Photo reconnaissance sorties
 
I was looking at some of the Peenemunde photographs and I noticed how the shadows made it so much easier to identify the launch tower and that the blast pit was cut into the ground and it got me thinking: Were reconnaissance sorties specifically planned for early morning or late evening to take advantage of the low sun angle?

...and if they were, did the enemy, or for that matter us, take this into consideration and expect those sorties to occur at those times?


wiggy 5th Dec 2021 14:58

Not sure about what was done WW2 but some spy satellites are deliberately put into what are known as Sun-synchronous orbits so that imaging of items of interest is always done under the same lighting conditions.

https://en.wikipedia.org/wiki/Sun-synchronous_orbit

Haraka 5th Dec 2021 16:15

Indeed "shadow" is the third of the traditional imagery interpretation criteria ( after "shape"and "size" and before "surface" and "associated features").
Most commercial optical imaging satellites hit at around 10:3O a.m. optimum local sun time for this reason.
Yes , the opposition was also often aware of this way back historically and would hide things away, e.g. back in the hangar., at that time if they knew there was recce about. :)

Aaaaaaaaaaaaaaaargh! 5th Dec 2021 17:55

thanks for the replies

Lordflasheart 6th Dec 2021 09:38

Stereo
 
.
If the answer is "Seventy-eight feet" - What is the question ?

Look up 'stereoscopic photographic interpretation.'
You don't need the sun for stereo pairs.

LFH

NB "Evidence in Camera" by Constance Babington-Smith is a very good read.
...

aroa 6th Dec 2021 10:50

To get the ‘texture’ of the terrain and shape shadows, low angle lighting is the go. Sun angle too high and the image can be ‘washed out’ and shape less distinctive/ defineable
With mapping photography in Oz, imagery could only be gathered in summer between 7.30 til 10.30 and 2.30 til 5.30 to avoid shadow point sun flare. In winter with the sun way north you could go all the (shorter) day as that effect never occurred. Further south one had a very short working/ imaging day..not enough sun angle.

These things would be ignored in war time recon of course.. grab some pics while the weather/ clear skies allows
Same with obligue views the right sun angle on the target from the right perspective can make a great difference in the quality of the photography.

I dips me lid to those guys who flew alone, unarmed,cold and high on long missions over enemy territory.
Or dashed about at low level, very much in harms way.

The last aircraft shot down over Oz was a Mitsubishi “Dinah”, that lovely sleek and fast Japanese recon twin.
Their pictures and the crew never made it home. Cosford has the last of type.

renfrew 6th Dec 2021 11:02

Were there many Japanese shot down over Australia?
Who got this one and where did it happen?

CoodaShooda 6th Dec 2021 13:29

www.Darwindefenders.org offers a snapshot of the activity in 40 odd Japanese raids.

I think the total number of raids against Northern Australia was around the 70 mark.

Initial defence was courtesy of USAAF P-40’s and, eventually, RAAF/RAF Spitfires; with some Boomerangs joining the mix.

Offensive operations were conducted by B24, B25, Beaufighter, Mosquito and Catalina.

rolling20 6th Dec 2021 15:22


Originally Posted by Aaaaaaaaaaaaaaaargh! (Post 11151663)
I was looking at some of the Peenemunde photographs and I noticed how the shadows made it so much easier to identify the launch tower and that the blast pit was cut into the ground and it got me thinking: Were reconnaissance sorties specifically planned for early morning or late evening to take advantage of the low sun angle?

...and if they were, did the enemy, or for that matter us, take this into consideration and expect those sorties to occur at those times?

One of the things that wasn't well known was the 3D imagery that was used to build a picture of Peenemunde.
https://www.bbc.co.uk/news/magazine-13359064
As far as I have always understood it, Peenemunde was photographed mainly by aircraft 'returning' from somewhere else in Germany, so not to arouse suspicion.
I wouldn't have thought they would have flown over at specific times, but with the 3D imagery taking pictures at certain times during daylight may not have been important?
One would have thought navigating back after dark after a late evening sortie would have been possible in a Mosquito, but somewhat difficult in a Spitfire.

Haraka 6th Dec 2021 16:01

Stereoscopy requires two displaced imagings of a target. In this case sun angle is irrelevant..

aroa 6th Dec 2021 20:51

The Dinahs demise was in the WA north coast area. Spitfires were rotated out of Darwin to protect the Truscott field , a B24 base near Kalumburu, an Aboriginal mission community, which had been shot up in the early days.
The Dinah fell into Vantissart Bay and was dragged ashore at low tide for examination.
Details from a book regarding that base. The usual thing with books….lent… and lost.

I don’t recall ever hearing a total count of Japanese a/c shot down on Oz soil. First raid on Darwin scored a few, and later raids also. TypeOs and Betty bombers with the occasional Dinah…some crashed on land but others into Darwin harbour and the Timor Sea. Likewise out of Thursday Island, a few down there but mostly into the water.
one Zero site on Hammond Is..

PR Mossies used to return the serves to the Japanese out of Truscott flying as far away as China.

Mapping wise.. sun angle on pale stockpiled material was important for ease of using the imagery to determine shape not ,washed out,


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