Drone Research Team

Drones Research Team - Research => Research (Detailed board) => : Nemo492 June 12, 2008, 02:58:47 AM

: Rajinder
: Nemo492 June 12, 2008, 02:58:47 AM
From Nekitamo, on OMF - June 12th
"Some people have magined the same background image was used in both pictures #16 and #17, although blurred and slightly perspective-corrected in PICT0017. Such "false" 2D perspective transforms are easily spotted as they don't produce true spatial shifting of objects like i.e. when you move your head to look what's behind something. This perspective shift in PICT0017 seems to be only a few pixels wide for the nearest objects and invisible due to the blur, but it is observable in position of the most remote wire (marked with red arrows in both images):"

(http://ovnis-usa.com/images/Nekitamo_perspectivechange.jpg)

"Additionally, I did some contrast enhancement (squares) to check for matching background noise which would also confirm the theory about the same background image being used for both pictures, but it is obviously different. All this indicates that we're indeed looking at two different images, though taken with the camera rotated (almost) around its no-parallax point. Just a coincidence or is Raj experienced in making images intended for panorama-stitching? Your guess is as good as mine... though he did mention he owns a camera (Canon)."
: Raj house
: Arkhangels July 31, 2008, 03:44:48 AM
Well like I posted some time ago in OMF, here's my modified image where I extended the side of the house in Raj's pictures and joined the two of them to get a full picture of the scene:

(http://i31.tinypic.com/13zmpfc.jpg)


Well I thought his house could look a lot like this, except the color and the construction artifacts:
(http://i35.tinypic.com/2u4ujcx.jpg)

Regards
Ark
: PICT0016: Drone tilt and shadows
: nekitamo July 31, 2008, 11:25:04 PM
I tried to determine the exact horizontal and vertical tilt of the drone in PIC0016 by overlaying a simple 3D model and here's what I came up with:

(http://img106.imageshack.us/img106/7937/pic16tiltax5.jpg)

Not exactly a perfect match, but close enough considering my poor 3D-modeling skills and simple (free) 3D application that I used. Drone size doesn't really matter here, but I used 4m diameter for drone ring (from my previous calculations of Chad's drone size) and set it on the appropriate height (36m) so it fits in (barrel corrected) PICT0016. As you can see, the drone indeed is slightly tilted relative to the ground level.

I didn't intend to analyze shadows, but tried to set proper sun angle anyway and - like others - failed to match shadows in Raj's image. But can sun really be simulated with some infinitely remote light source like it's done in similar 3D programs? Here's what I think really happens with light and shadows in the following situation (I used somewhat wider angle to show assumed position of the sun in relation to the original image):

(http://img293.imageshack.us/img293/6026/p16wideix4.jpg)

Note that there's no shadow below the large paddle and that top crossbar shadow also fits Raj's image. So does it really matter how far is the sun or is it just about how it "sits" in the image perspective? Hope we'll be able to verify this once HPO's model is ready...

EDIT TO ADD: I was wrong about the shadows, check my next post...
: Re: Rajinder
: elevenaugust July 31, 2008, 11:32:53 PM
Well done, Neki!  ;)
I guess you assume in your recreations that the pole is perfectly straight at a 90° angle, but do you think that a 85 or 95° pole angle can change anything in this situation??
: Re: Rajinder
: HPO August 01, 2008, 12:04:19 AM
Nicely done !!, two questions though, can you make a side view of this scene, so that the height of the sun is also visible?
And is it possible for you to make a simple "crown" underneath the torus, so we can check the shadows of those as well.

P.S.  I will try those angles myself in Vue6 when I find the time.
: Re: Rajinder
: nekitamo August 01, 2008, 12:11:25 AM
I guess you assume in your recreations that the pole is perfectly straight at a 90° angle, but do you think that a 85 or 95° pole angle can change anything in this situation??

Well, my (first) image would still look the same (as there's no ground visible), except for the different drone angle values. I did use straight pole, but if it is tilted exactly opposite of what I assumed to be the drone tilt, then the drone may be perfectly level - I admit! :)

As for the shadows, if I'm correct in my assumption it wouldn't matter as long as the sun keeps the same relative relative position in wider image perspective. It would only affect shadows on the ground, which aren't visible anyway.
: Re: Rajinder
: leviathan August 01, 2008, 03:14:46 AM
But can sun really be simulated with some infinitely remote light source like it's done in similar 3D programs?

No it can not, but the "experts" at this other forum are not telling you that and they should know.  I use parallel and distant light settings along with a host of other refinements in Cinema 4D.  There is no switch that will simulate real world lighting not even HDR lighting.  Nature does not play by my rules or their rules or your rules.  Just take a walk in nature and try to explain every lighting condition and shadow you see.  The arrogance of humans is to believe that everything plays by human rules.  It does not.  How can anyone ever explain a truly ALIEN DEVICE without knowing anything about the rules it feels compelled to obey?
L E V I A T H A N
: Re: Rajinder
: leviathan August 01, 2008, 06:21:03 AM
(http://i239.photobucket.com/albums/ff230/ter123abc/PICT14Lighting.jpg)
If the time and date in the camera are not correct the data is of no value.  Does someone know this camera is set properly and if so how!!! Is it by an assumption, if so then the "facts" are assumed!
L E V I A T H A N
: Re: Rajinder
: BigFnTuna August 01, 2008, 06:39:52 AM
(http://i239.photobucket.com/albums/ff230/ter123abc/PICT14Lighting.jpg)
If the time and date in the camera are not correct the data is of no value.  Does someone know this camera is set properly and if so how!!! Is it by an assumption, if so then the "facts" are assumed!
L E V I A T H A N

Agreed!  It's funny how some people shout hoax by CGI, but then say the CGI shadows are incorrect!
: Re: Rajinder
: tomi August 01, 2008, 09:52:59 AM
But can sun really be simulated with some infinitely remote light source like it's done in similar 3D programs?

No it can not, but the "experts" at this other forum are not telling you that and they should know.  I use parallel and distant light settings along with a host of other refinements in Cinema 4D.  There is no switch that will simulate real world lighting not even HDR lighting.  Nature does not play by my rules or their rules or your rules.  Just take a walk in nature and try to explain every lighting condition and shadow you see.  The arrogance of humans is to believe that everything plays by human rules.  It does not.  How can anyone ever explain a truly ALIEN DEVICE without knowing anything about the rules it feels compelled to obey?
L E V I A T H A N

So true...... Just a layperson who loves to read and think about such things as light.. And thanks to one far more knowledgeable member here, I've got the most beautiful Electromagnetic Radiation Spectrum chart on my study wall.   

In the way that I simply understand it, light = energy packets and is our visible portion of the EMR spectrum. Light is photons, that behave as a wave until observed as a single photon, then it behaves like a particle.  Unknown physics are at work here which makes reproducing nature, in formulas describing light behaviour by using known physics rather challenging and never complete.  IMHO
 
: Re: Rajinder
: 10538 August 01, 2008, 05:20:24 PM
If the time and date in the camera are not correct the data is of no value.  Does someone know this camera is set properly and if so how!!! Is it by an assumption, if so then the "facts" are assumed!
L E V I A T H A N

It's entirely possible the date and time are not correct.  It's basically like setting a watch.  But then you have to ask yourself, why keep a watch with the incorrect time?  The most likely scenario is the date is set correctly and does coincide with the Raj report.  The only question about the time is how accurate it is.  I have one of the Minolta Dimage X cameras and the time has not deviated since I set it.  Still correct to the minute (I just checked it). 

The only realistic question in my mind is, was the camera's time updated properly for daylight savings time?  In 2007, daylight savings time started March 11, more than two months before the fateful day.  Did Raj's in-laws make the adjustment?  I believe Spf33 did some analysis on the shadow on the side of the house/building.  He may be able to verify this.
: Re: Rajinder
: spf33 August 01, 2008, 05:39:59 PM
I believe Spf33 did some analysis on the shadow on the side of the house/building.

suppose i should probably get hpo's model in the scene at some point...

(http://img152.imageshack.us/img152/7137/rajhouseorientationcy8.th.jpg) (http://img152.imageshack.us/img152/7137/rajhouseorientationcy8.jpg)
: Re: Rajinder
: nekitamo August 02, 2008, 04:39:49 PM
...can you make a side view of this scene, so that the height of the sun is also visible?
And is it possible for you to make a simple "crown" underneath the torus, so we can check the shadows of those as well.

P.S.  I will try those angles myself in Vue6 when I find the time.


Don't bother, I was wrong! Disregard my previous post...  :-\

After adding the "crown" like you suggested, I tried again to match the shadows with the original image and now I believe it can be done - the key is in the crossbar shadow!

I kept thinking it was that big smear bellow, but it's not - I'm not sure what produces that one. The crossbar shadow is actually much smaller and sharper - it was right under my nose all this time and I didn't see it! Once i figured this out, almost everything fits with only a slightest tilt for the drone:

(http://img123.imageshack.us/img123/2256/p16newig2.jpg) (http://imageshack.us)

Drone geometry seems very important for proper shadows, so I believe my poor model is to blame for most of the differences.
: Re: Rajinder
: leviathan August 02, 2008, 04:46:15 PM
(http://i239.photobucket.com/albums/ff230/ter123abc/PICT16Lighting1.jpg)
The pole is just as strange as the Drone in lighting and shadow, because they are both residing in nature at the same time enjoying the way nature does things instead of how we think nature does things.
L E V I A T H A N
: Re: Rajinder
: tomi August 02, 2008, 05:48:57 PM
Thank you, thank you, thank you Lev.

If you didn't do that, I was feeling compelled to do something similiar.
Yes for a fact, there has to be some ambient sun that corresponds to both those areas not being in shade.  It could be the elevation and the angle, but for sure those areas correspond.

And when you see spf33's last post on OMF, his work shows the sun to be about where it would prevent those areas under the boom and the bar from the pole to be in direct exposure of sun, due to the suns position and the tilt of the drone especially.

Thank you!
: Re: Rajinder
: 10538 August 02, 2008, 08:47:46 PM
Check out four seconds of cloud movement.

(http://home.comcast.net/~dl1027/files/object/RajClouds.gif)

: Re: Rajinder
: tomi August 02, 2008, 08:57:54 PM
Check out four seconds of cloud movement.

(http://home.comcast.net/~dl1027/files/object/RajClouds.gif)



Good work numbers!  Keeps looking more and more on the real side, the more we look..  In this case it looks like the clouds are going 4 seconds in the opposite direction of the drone.  Very interesting...  ;D 
: Re: Rajinder
: spinnewise August 02, 2008, 09:12:46 PM
I think I know what causes the long shadow beneath the crossbar shadow. It is the big white insulator to the right of the pole.
Hope you know which one I mean.
: Re: Rajinder
: 10538 August 03, 2008, 05:10:31 PM
Good work numbers!  Keeps looking more and more on the real side, the more we look..  In this case it looks like the clouds are going 4 seconds in the opposite direction of the drone.  Very interesting...  ;D 

I think the cloud movement makes a good case for the photos being real and the timing as stated in the exif.  If fake the drone would have to be composited in. 
: Re: Rajinder
: tomi August 03, 2008, 09:44:23 PM
Good work numbers!  Keeps looking more and more on the real side, the more we look..  In this case it looks like the clouds are going 4 seconds in the opposite direction of the drone.  Very interesting...  ;D 

I think the cloud movement makes a good case for the photos being real and the timing as stated in the exif.  If fake the drone would have to be composited in. 


Yes,, It's just one more natural detail that those who are drone challenged will have to accept.. LOL  :D
: Re: Rajinder
: Arkhangels August 03, 2008, 10:25:02 PM
Don't bother, I was wrong! Disregard my previous post...  :-\

After adding the "crown" like you suggested, I tried again to match the shadows with the original image and now I believe it can be done - the key is in the crossbar shadow!

I kept thinking it was that big smear bellow, but it's not - I'm not sure what produces that one. The crossbar shadow is actually much smaller and sharper - it was right under my nose all this time and I didn't see it! Once i figured this out, almost everything fits with only a slightest tilt for the drone:

(http://img123.imageshack.us/img123/2256/p16newig2.jpg) (http://imageshack.us)

Drone geometry seems very important for proper shadows, so I believe my poor model is to blame for most of the differences.

WOW!
Nice job, I think your "simple" model is so complete as it needs to be to prove us that the scene presented in that particular Raj photo is plausible.
It even explains the lightning that me and Onthefence were trying to understand. That one right in the side of what you called "small fin shadow".

Now I ask Onthefence to check this out! :)

Nice work Nekitamo. Sometimes, it's not a good software that makes a good analysis, you proved it  ;)

Regards
Ark
: Re: Rajinder
: onthefence August 04, 2008, 02:54:36 AM
Now I ask Onthefence to check this out! :)

Yes, I have been watching. I previously only addressed one issue of the interesting shadow relationship between two pieces of the drone (fin shadow and highlighted nub):

(http://i294.photobucket.com/albums/mm106/onthefence55/issues2.jpg)

I was only able to reproduce this exact lighting example by bending the small middle (10 o'clock) fin downward a few degrees:

(http://i294.photobucket.com/albums/mm106/onthefence55/model2_reduced.jpg)

(http://i294.photobucket.com/albums/mm106/onthefence55/modelk2.jpg)

All other lighting example studies included too many variables for me to analyse in one setting:
: Re: Rajinder
: onthefence August 04, 2008, 04:08:02 AM
The conclusion that I drew from my shadow study is that the arms of the drone are not lying on one plane as they would if it was slapped together in CGI.

I suspect that the drone arms are moveable for some purpose.
: Re: Rajinder
: 10538 August 29, 2008, 07:47:29 PM
Explanation of the pole equipment.  May provide a clue as to the location.

(http://home.comcast.net/~dl1027/files/object/PoleInfo.jpg)
: Re: Rajinder
: onthefence September 04, 2008, 03:04:56 PM
Frank (PI) pointed out that there appears to be a yellow label on the cross-arm of the pole shown in PICT15 (http://droneteam.com/history/raj/PICT15.jpg).

I'm not sure if there is a way to enhance this to reveal any lettering, here is the cropped and rescaled image without interpolation.

(http://i294.photobucket.com/albums/mm106/onthefence55/PICT15_labelcrop.jpg)
: Re: Rajinder
: 10538 September 04, 2008, 04:27:16 PM
Frank (PI) pointed out that there appears to be a yellow label on the cross-arm of the pole shown in PICT15 (http://droneteam.com/history/raj/PICT15.jpg).

Most likely "High Voltage".  Those lines there carry 7k to 15k volts.  It may be a code requirement that the top be labeled that way.

: Re: Rajinder
: majicbar December 21, 2008, 08:31:41 PM
Explanation of the pole equipment.  May provide a clue as to the location.

(http://home.comcast.net/~dl1027/files/object/PoleInfo.jpg)

Also note that the lines from the pole going to the bottom of the picture are only two lines, indicating that it is not full phase power, meaning that it is only supplying power for lighting and not motors. This may indicate that it is supplying power for the lighting of a parking lot, which may indicate that it is near a park of some kind.
: Re: Rajinder
: majicbar December 21, 2008, 08:44:11 PM
Pictures 15 and 16 may supply enough information to do some kind of photogrametric analysis. It has occured to me that we have established that the long arm, paddle, undergoes a perspective change, or foreshortening in Chad's photographs, and this will be the same in Raj's. For a known ratio of lengths, such as is provided by photo 16, the distance to this feature on the drone in 15 will change ratios given only one particular distance. We know the dimensions of the streetlamp in photo15, given the lens of the camera we should be able to consider its distance. We pretty much have some confidence in the dimensions of the crossbars on the telephone pole, 8 feet is my recollection. we can pretty much figure the width of the street is standard and thus we should be able to set the dimensions of the scene. Given the ratio of the long arm on the drone in photo15 and its ratio as given by photo16, we should be able to then establish the distance to the drone in photo15, and then its size by the relative distance to the streetlamp vs that to the drone.
: Re: Rajinder
: 10538 December 21, 2008, 09:47:09 PM
Also note that the lines from the pole going to the bottom of the picture are only two lines, indicating that it is not full phase power, meaning that it is only supplying power for lighting and not motors. This may indicate that it is supplying power for the lighting of a parking lot, which may indicate that it is near a park of some kind.

One thing to note,

On our visit to Capitola, 11A and I talked to a Comcast lineman who was working on a pole.  He was very friendly and quite interested in our little pole search.  After looking at our picture of the pole he claimed the cable amplifier to not be of the Comcast type.  He believed it to be from a competitor called "Charter".  Maybe somebody can ascertain which areas of Capitola are serviced by Charter.  That may narrow the search.
: Re: Rajinder
: majicbar December 22, 2008, 10:17:18 AM
Charter Communications does not appear to have a good operation going in Capitola, Ca., but it looks like it could be anywhere in Capitola.

http://www.santacruzsentinel.com/localnews/ci_10562723

 

Capitola council tells Charter Communications to fix problems

By JONDI GUMZ - Sentinel staff writer
Article Launched: 09/26/2008 01:24:22 AM PDT


CAPITOLA - Improve in 30 days, or there will be consequences.
That's the message Capitola Mayor Kirby Nicol gave Charter Communications, the company with a monopoly on the city's cable service, Thursday night. Councilman Sam Storey took the same stance.

 
 
 
: Re: Rajinder
: spf33 December 23, 2008, 06:17:54 PM
we can pretty much figure the width of the street is standard and thus we should be able to set the dimensions of the scene. Given the ratio of the long arm on the drone in photo15 and its ratio as given by photo16, we should be able to then establish the distance to the drone in photo15, and then its size by the relative distance to the streetlamp vs that to the drone.

reminded me that i don't think i ever did any distance measurements on pic 15.

(http://img525.imageshack.us/img525/3056/rajpic15hpodistancesju1.jpg)

measurement between the center of the utility pole and the center of the rectangular lamp.  so add maybe another 5' to the distance between the base of the out of frame light pole and the center of the main utility pole -about 40', which seems like a 2 lane road - 12' in each direction with an 8' shoulder on each side?

also, assuming both poles are on level ground then the lamp head is sitting about 20' off the ground the utility pole is measuring out to 39' high.  also not shown is the camera lens height of 5'6" from the ground.
: Re: Rajinder
: nekitamo December 24, 2008, 08:39:38 AM
Hi, spf33!

As you also recreated both images in 3D, could you please verify if my conclusion about the mutual spatial orientation of the poles in pics #15 and #16 is correct:

(http://img504.imageshack.us/img504/5920/1516280jg2.jpg)

This is based on assumption that both images were recorded at the approximately same time of day with sun angle of ~280 degrees - seems pretty safe, as I had no problem matching shadows on both poles with their respective images by using the same light source.

If correct, this piece of information would be of great help in our search for the poles in Google Earth as it's much easier to look for something when you know what it should look like. :)
: Re: Rajinder
: majicbar December 24, 2008, 08:43:55 AM
This should help me in looking for the spot I hope. Thanks.

I'd much rather go there and drive around looking for it, especially give all the snow we've been getting here in the Minneapolis area. My brother just took a job at Apple, but lives in Santa Cruz, maybe I should go for a visit.