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</div>= --_000_CCBBF6F84AC84388B2E4C20C68B1211Edalca_ Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Hi Dave and others, At risk of flogging a dead horse, I=92ll take up cudgels with Dave=92s call= that "35=B0 from image horizontal when measured [see below]... means almos= t nothing". In the BBC interview, this UK guy has a big rig camera and app= ears to be an experienced photographer. Anyone like this who has to take a= snap decision for a quick bird photo is going to try to hold the rig horiz= ontal, and my guess is that anyone competent could hold it level to within = =B12=B0 of horizontal, even me. Photographers may wish to comment. How about 'when measured=92? I imported a JPEG copy of the woodpecker-weas= el image into the very useful image analysis program ImageJ*, and with the = angle-measurer tool measured the shadow angle from the vertical at 47.17=B0= (=B1 1.5% coefficient of variation, n=3D7); my eyeball guess had been 50= =B0, and the very low CV% means that the wing shadow, clear and almost line= ar, made it possible to make very reliable repeat measurements. The sun=92= s implied elevation then is (90 minus this), or 42.83=B0, not 35=B0. I thought it would take at least a degree in Astronomy (not me) and a load = of work to estimate where the sun actually was on the day in question in th= at part of UK, but this turns out to be relatively easy. For the calculation you first need the coordinates of the site from one of = the several latitude-longitude calculators available on the web, for instan= ce: www.latlong.net/<http://www.latlong.net/> The result is latitude 51.562254, longitude 0.218605, for Hornchurch, E. Lo= ndon, UK. Several sun height calculators are also available, for instance: keisan.casio.com/exec/system/1224682277<http://keisan.casio.com/exec/system= /1224682277> Besides the latitude and longitude, the date needs to be specified, which i= s the Monday the day before the BBC post, therefore 1 March 2015; zero refe= rence, 0 GMT; then the time (not yet daylight saving time) which is only gi= ven in the BBC post as 'afternoon=92. My guess for this would be ~3PM, bu= t maybe it could have been as early as 2PM. The results returned by the calculator for sun elevation (altitude measured= from earth horizontal) using these 1 March 2015 values for Hornchurch are 2PM: 26.47=B0 3PM: 20.78=B0 4PM: 13.47=B0 The maximum height of the sun on that day occurs near 12:30PM, but is still= only 30.74=B0 Conclusion: The measured estimate of the sun=92s elevation from the JPEG (= 42.83=B0), is therefore too high by 16.4=B0 at 2PM, and 22.4=B0 at 3PM, to = have been taken on 1 March 2015. I don=92t believe that an experienced pho= tographer would be holding his camera at anywhere near either of these angl= es to make the situation right. And if that were true, the loaded woodpeck= er would actually be heading upwards by 22=B0 (3PM), probably close to stal= l angle. In fact according to the report, the woodpecker was heading towar= ds a crash landing, therefore downwards. Another way to look at it using the Keisan calculator is to ask on what fir= st date/time the sun elevation would equal close to the value measured from= the image, 42.83=B0. The answer is several weeks later than 1 March, on 23= May 2015 (if 3PM) and on 19 April (if photo was taken at 2PM). This seems like pretty good evidence that this photo could not have been sh= ot on or even close to 1 March 2015. If the =91Monday=92 in question were= even earlier in the year, the sun would be lower and the angle fit would b= e even worse. Among other salient points, Randy=92s is particularly persu= asive, about the relative weight of the weasel with solid bones versus the = woodpecker=92s hollow bones implying that the bird could not fly carrying s= uch a large load. The only powerful point of view that needs to be considered is that of the = weasel itself, as relayed in Dave=92s original post, which in case you miss= ed it was: >> But as, is often the case, the passenger felt he was taken. http://newsthump.com/2015/03/03/weasel-shocked-by-hidden-charges-after-chea= p-woodpecker-flight/ DW<< Steve (Hfx) *Google to ImageJ, select the site and download the version for your operat= ing system. It is a very useful, powerful but easy to use program, develop= ed and maintained to the present with US govt funds and so is available for= free. Highly recommended. -------------------------------------------------- On Mar 4, 2015, at 11:31 AM, David & Alison Webster <dwebster@glinx.com<mai= lto:dwebster@glinx.com>> wrote: Hi Steve & All, I think there is no reason to suppose it not to be genuine. The angle of shadow cast by the wing, more like 35o from the image horizo= ntal when measured, means almost nothing because this angle would be depend= ent upon the angle of the camera relative to true horizontal. One would exp= ect a loaded bird to fly with maximum angle of attack so as to avoid an uns= cheduled pancake landing. The foreleg, being small, against the bird, perhaps somewhat buried in sh= ort feathers, with an edge of sparse fur to cast the shadow, the shadow tra= ce possibly dimmed by light reflected from the neck and just barely at a gr= eater angle from the image horizontal than the wing shadow would be expecte= d to cast faint or no detectable shadow. Even the shadow distal to the foot= is very faint. This is in addition to the complaint registered by the passenger which ad= ds authenticity. Why would a non-existent passenger complain about being tr= eated unfairily ?. Time will tell. Yt, Dave Webster, Kentville ----- Original Message ----- From: "Stephen Shaw" <srshaw@Dal.Ca<mailto:s= rshaw@Dal.Ca>> To: <naturens@chebucto.ns.ca<mailto:naturens@chebucto.ns.ca>> Sent: Wednesday, March 04, 2015 1:57 AM Subject: Re: [NatureNS] BBC Article - Weasel photographed riding on a woodp= ecker's back Hi Keith, I could only find one other shot, a low power pan with poor focus which the= refore doesn=92t resolve anything. Do you have a URL for other shots? If you look at the prominent bright area on the side of the bird=92s throat= which abruptly turns into a dark shadow on the breast just forward of the = wing, this must have been shot in bright sunlight (in mid afternoon in Febr= uary, apparently). From the angle of the shadow (caused by occlusion by th= e bend of the extended wing), sunlight would have to have been falling from= the right, top, about 50 degrees off vertical, and roughly in the plane of= the photo. I=92m not sure, but am surprised that the