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Post by BertL on May 11, 2007 19:17:15 GMT -4
I remembered when David Greer posted a photograph showing the same phenomenon as the Apollo photograph with the very converging shadows (20744/20747). www.youtube.com/watch?v=ra9NJqPqH04Here's Jarrah White's response. Basically, JW assumes the photograph made by David Greer is has a much wider angle than the Hasselblad's photograph and therefore is wrong. Sorry, I couldn't find the original thread. EDIT: And for some unexplainable reason Jarrah gives a Special Thanks to Straydog.
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JMV
Venus
Posts: 41
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Post by JMV on May 12, 2007 2:15:31 GMT -4
This one?Horizontal FOV of David's photo should be about 24 degrees, if the info about the camera is correct or if I did my math right. In the Apollo photo it's 49.2 degrees. The photographers' shadows should have been Jarrah's first clue to implicate that his idea of angular width three times as wide can't be correct. That would have meant that David's shadow is as wide as the whole FOV of the Apollo picture. That's just laughable... unless David is really really fat. Why did Jarrah fail to realize this?
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Post by donnieb on May 12, 2007 7:25:53 GMT -4
A list of things Jarrah White fails to realize would fill my hard drive.
... and it's a biiiiig hard drive.
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Post by aes53 on May 12, 2007 11:48:48 GMT -4
I watch the Youtube and was stunned. This guy White is an iodiot, I could let monkey loose in my lab and they would come up with better experiments. He thinks that a 60 mm lens on a Hasselblad and a 60 mm lens on his little video camera provide the same fiedl of view in the image. They don't, it depend on the diameter of the film (or ccd chip in a digital camera). A "normal" lens for a Hasselblad focused using 6 cm X 6 cm film is 80 mm (approximately the diagonal of the film), the "normal lens" for 35 mm film is 50 mm, both provide (correcting for differences in the rectangular vs square format) exactly same angle of view on the exposed film. He's using a ~60 mm lens on what looks like a small digital camera, which is the equivalent to a long telephoto in that CCD sensor.
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Post by HeadLikeARock (was postbaguk) on May 12, 2007 19:59:52 GMT -4
I don't know, Jarrah White making videos about my photo, my name in lights on here... Infamy! Infamy! They've all got it in for me! If anyone's still interested, there's plenty of discussion on this photo on the Education forum here. Jarrah made a catalogue of errors in his video. (a) Incorrectly stated the lens I used was 24mm, it's actually a 3x zoom lens, f=8-24mm. Only a very minor error. (the focal length used in my beach photo was actually 18mm) (b) Incorrectly stated the lens on his OWN camera was 57mm - it's actually a 30x zoom lens with f=1.9-57mm. A bigger error. For him to have a focal length of 57mm, he would have been zoomed all the way in - 30x! (c) Failing to realise that film format or CCD sensor size directly affects angle of view. Major error which nullifies the entire premise of his film. He also failed to respond to having this error pointed out to him several times on the comments boards. (d) Stated that I was "boasting" about my photo on this forum to the cheerfully blind! He shouldn't really have got my gander up. (e) Stating "As a trained and experienced photographer, I can assure you that the lonely (?) sun would not cause shadows to fall on a surface like this." I think this last comment may come to back haunt him... The email stuff is nonsense too - I have the originals to prove my point but I'm bored of the whole darned shooting match to be honest.
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Post by HeadLikeARock (was postbaguk) on May 12, 2007 20:01:52 GMT -4
That would have meant that David's shadow is as wide as the whole FOV of the Apollo picture. That's just laughable... unless David is really really fat. Why did Jarrah fail to realize this? I was wearing a thick leather jacket, honest guv!
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Post by Obviousman on May 12, 2007 20:11:37 GMT -4
"Trained & experienced photographer"?
What training? What experience?
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Post by HeadLikeARock (was postbaguk) on May 12, 2007 20:17:55 GMT -4
"Trained & experienced photographer"? What training? What experience? Good question. I'll have a guess at the answers. Insufficient. Anyone can make mistakes, but making these claims and then going on to make a catalogue of basic errors and failing to correct them is, well, a bit naughty IMO. Maybe it's something to do with being called J. White?
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Post by scooter on May 12, 2007 20:59:45 GMT -4
I'm not an avid photog, but I know enough to realize that a 60mm lens on the Hasselblad and a 60mm on my old 35mm Pentax are completely different fields of view. Jarrah also recommended a 24,000mph orbit, so this latest faux pas is no great revelation. Sorry JW, keep swingin'...
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Post by nomuse on May 12, 2007 21:07:23 GMT -4
How much experience do you have to have to encounter a term like "50mm equivalent?" How many cameras can you own without discovering that the 50mm lens on one performs nothing like the 50mm lens on another (another with a different film format, that is!) I'm sorry, but missing this point is so hard I think one would have to be willfully blind -- or intentionally deceptive.
Heck -- I've owned maybe a half-dozen cameras in my life (and most of those were throw-away 120's). Must have been twenty years ago, back when I first got that Minolta 201, that someone at a camera store said something like "That's a 35mm lens, which on this camera counts as a wide-angle." The light dawns then. Oh, so "50mm lens isn't the _only_ thing you have to know to compare field of view?"
(By the by, for many years theater lighting people have referred to the class of ERS -- Ellipsoidal Reflector Spotlights -- in the format "x by y." With "x" being the size of the front lens, and "y" being the focal length (or more precisely, the distance from front lens to the focal point inside the instrument, where the shutters and pattern holders reside). During a typical lighting hang someone will cry "We got anymore 6x12's down there?" and the answer will be shouted up "Naw, just 6x9's -- but got some 4.5" zooms that will get down to 30 degrees."
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Post by Waspie_Dwarf on May 12, 2007 21:20:24 GMT -4
"Trained & experienced photographer"? What training? What experience? Hell, I'm both trained (a half unit whilst doing a course in Chemistry) and experienced (I've owned various cameras for more than 30 years). It doesn't prove that I'm any good.
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Post by BertL on May 13, 2007 8:30:57 GMT -4
I'm not an avid photog, but I know enough to realize that a 60mm lens on the Hasselblad and a 60mm on my old 35mm Pentax are completely different fields of view. Jarrah also recommended a 24,000mph orbit, so this latest faux pas is no great revelation. Sorry JW, keep swingin'... He'll probably be mad at me for saying it, but... 500 kilogram hammers, anyone?
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Post by craiglamson on May 13, 2007 9:48:38 GMT -4
Heres an interesting aside to the focal length debate. Lets take a 50mm lens for a Hasselblad and a 50mm lens for a full frame Canon 35mm format digital camera.
Now the Hassey 50mm is a wide angle on the 6x6 camera, and the Canon 50mm is a normal on the Canon 35mm camera right? The Hassey has a much wider FOV AND image circle to cover the 6x6 format,
Now here is where it gets fun...50mm is still 50mm. If I place the Hasselblad 50mm on my Canon 1DsMKII via an adapter (which I own and have done) and take picture...then change lenses to the Canon 50mm and take the same picture without moving the camera,both images will show the exact FOV.
Of course a shot with the Hasselblad 50mm on a full frame 35mm camera will not show the same FOV as the 50mm Hasselblad lens on a 6x6 Hasselblad camera. The Hasselblad/Hasselblad shot will show a much wider FOV...because 50mm is a wide angle lens...on the Hasselblad.
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Post by aes53 on May 13, 2007 10:57:37 GMT -4
Hi, can anyone tell me what camera, make and model, White was using, I could not quit tell from his video. If you know the size of the ccd in his camera it's trivial to calculate what the equivalent lense would be in a 6x6 format camera.
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JMV
Venus
Posts: 41
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Post by JMV on May 13, 2007 12:02:43 GMT -4
Looked like a Panasonic PV-GS35 with zoomable lens from 1.9 mm to 57 mm focal length and equivalent 35 mm focal length 35.7 - 1072 mm. That works out to a crop factor of 18.8 for a 35 mm camera and 33.8 for a 70 mm one. Equivalent 70 mm focal length would be 64 - 1927 mm.
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