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the photo. I=92m not sure, but am surprised that the --Apple-Mail-2F2BACF0-54E9-455F-B847-B246DCD333D9 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable I can't tell if this is a joke post or not.=20 Sent from my iPhone > On Mar 7, 2015, at 11:47 PM, Stephen Shaw <srshaw@Dal.Ca> wrote: >=20 > Hi Dave and others, > At risk of flogging a dead horse, I=E2=80=99ll take up cudgels with Dave=E2= =80=99s call that "35=C2=B0 from image horizontal when measured [see below].= .. means almost nothing". In the BBC interview, this UK guy has a big rig c= amera and appears to be an experienced photographer. Anyone like this who h= as to take a snap decision for a quick bird photo is going to try to hold th= e rig horizontal, and my guess is that anyone competent could hold it level t= o within =C2=B12=C2=B0 of horizontal, even me. Photographers may wish to co= mment. >=20 > How about 'when measured=E2=80=99? I imported a JPEG copy of the woodpeck= er-weasel image into the very useful image analysis program ImageJ*, and wit= h the angle-measurer tool measured the shadow angle from the vertical at 47.= 17=C2=B0 (=C2=B1 1.5% coefficient of variation, n=3D7); my eyeball guess had= been 50=C2=B0, and the very low CV% means that the wing shadow, clear and a= lmost linear, made it possible to make very reliable repeat measurements. T= he sun=E2=80=99s implied elevation then is (90 minus this), or 42.83=C2=B0, n= ot 35=C2=B0. =20 > 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.=20 >=20 > 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:=20 > www.latlong.net/ =20 > The result is latitude 51.562254, longitude 0.218605, for Hornchurch, E. L= ondon, UK. >=20 > Several sun height calculators are also available, for instance:=20 > keisan.casio.com/exec/system/1224682277 =20 > 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 refer= ence, 0 GMT; then the time (not yet daylight saving time) which is only give= n in the BBC post as 'afternoon=E2=80=99. My guess for this would be ~3PM,= but maybe it could have been as early as 2PM. >=20 > The results returned by the calculator for sun elevation (altitude measure= d from earth horizontal) using these 1 March 2015 values for Hornchurch are > 2PM: 26.47=C2=B0 > 3PM: 20.78=C2=B0 > 4PM: 13.47=C2=B0 > The maximum height of the sun on that day occurs near 12:30PM, but is stil= l only 30.74=C2=B0 >=20 > Conclusion: The measured estimate of the sun=E2=80=99s elevation from the= JPEG (42.83=C2=B0), is therefore too high by 16.4=C2=B0 at 2PM, and 22.4=C2= =B0 at 3PM, to have been taken on 1 March 2015. I don=E2=80=99t believe tha= t an experienced photographer would be holding his camera at anywhere near e= ither of these angles to make the situation right. And if that were true, t= he loaded woodpecker would actually be heading upwards by 22=C2=B0 (3PM), pr= obably close to stall angle. In fact according to the report, the woodpecke= r was heading towards a crash landing, therefore downwards. >=20 > Another way to look at it using the Keisan calculator is to ask on what fi= rst date/time the sun elevation would equal close to the value measured from= the image, 42.83=C2=B0. The answer is several weeks later than 1 March, on 2= 3 May 2015 (if 3PM) and on 19 April (if photo was taken at 2PM). >=20 > This seems like pretty good evidence that this photo could not have been s= hot on or even close to 1 March 2015. If the =E2=80=98Monday=E2=80=99 in q= uestion were even earlier in the year, the sun would be lower and the angle f= it would be even worse. Among other salient points, Randy=E2=80=99s is par= ticularly persuasive, about the relative weight of the weasel with solid bon= es versus the woodpecker=E2=80=99s hollow bones implying that the bird could= not fly carrying such a large load.=20 >=20 > The only powerful point of view that needs to be considered is that of the= weasel itself, as relayed in Dave=E2=80=99s original post, which in case yo= u missed it was: >=20 > >> But as, is often the case, the passenger felt he was taken. > http://newsthump.com/2015/03/03/weasel-shocked-by-hidden-charges-after-che= ap-woodpecker-flight/ > DW<< >=20 > Steve (Hfx) >=20 > *Google to ImageJ, select the site and download the version for your opera= ting 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 f= ree. Highly recommended. >=20 > -------------------------------------------------- >=20 >> On Mar 4, 2015, at 11:31 AM, David & Alison Webster <dwebster@glinx.com> w= rote: >> Hi Steve & All, >> I think there is no reason to suppose it not to be genuine. >>=20 >> The angle of shadow cast by the wing, more like 35o from the image hori= zontal when measured, means almost nothing because this angle would be depen= dent 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 unsc= heduled pancake landing. >>=20 >> The foreleg, being small, against the bird, perhaps somewhat buried in s= hort 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 gre= ater angle from the image horizontal than the wing shadow would be expected t= o cast faint or no detectable shadow. Even the shadow distal to the foot is v= ery faint. >>=20 >> This is in addition to the complaint registered by the passenger which a= dds authenticity. Why would a non-existent passenger c