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High-Speed Flash, News

In Remembrance of Tony Allen

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balloon_Tony_Allen

Just received some very sad news that my high-speed videographer friend Tony Allen passed away last week.

We had a fantastic day in Tony’s studio in Oxford (quite a few years ago now) taking high-speed flash (stills) shots of water-filled balloons being shot by an air pistol. The high-speed flash was triggered by the sound of the pistol firing and we used the open-flash technique to capture the shot.

On a couple of the shots when I looked at the capture on the camera screen it looked like we had the flash trigger timing wrong as the balloon was still intact. But then a closer look at the image gave the stunning result shown above. You can see the pellet to the left of the balloon is still (remarkably) contained within the intact balloon. I like to say we got the flash synchronisation spot-on for this shot – but it was in fact pure fluke.

That was a great day Tony that I shall always remember fondly.

Deep-Sky Imaging

The Full Extent of the California Nebula

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Calif3_n

There is a LOT more to the California nebula than you usually see in the posted images. This is 24 x 20-minute subs taken with the Canon 200mm prime lenses, ASI 2600MC Pro OSC CMOS cameras, and the Optolong L-Enhance filters. Notice the long “nose” which is usually absent on images of this one. I wonder how much more I can get out of this one by getting more subs?

 

Special Projects

The Golden Solid Angle – Yet Again!!

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Another hobby of mine is “experimental mathematics” – I think I may have mentioned (ages ago) my Prime number hunting server.
Well way back in June 2007 (just before actually) I discovered something that seems to have been overlooked for centuries – The Golden Solid Angle.
Everybody knows the basics, the 1-D Golden Ratio, the 2-D Golden Angle (equal to 2*Pi/Golden Ratio^2) and there it seems to have come to a halt for a few centuries. Why hasn’t anybody (until moi) taken this up one further dimension to form the Golden Solid Angle? Or have they? Nobody has got back to me on this and I’ve not seen it in any book or publication on the subject. So why not?
To find the Golden Solid Angle (in steradians) is pretty straightforward. Draw a sphere of radius r with the total surface area of the sphere being 1 + Golden Ratio. Then the solid angle subtended by the unity area part of the sphere is the Golden Solid Angle which is given by 4*Pi/Golden Ratio^2.
I have just sent this off to Wolfram Mathematica to see if they will publish it. Way back in 2007 I sent it off to the Mathematical Gazette and they answered – “Just because it is a new discovery in mathematics doesn’t make it necessarily publishable” which after a lifetime in science with over 120 refereed research journal publications to my name – was a new one on me.
Let’s see if the Stephen Wolfram outfit are a little more enlightened – or not
Special Projects

Fibonacci-Primes

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Here are the first 200 Fibonacci numbers, and the list below them shows you whether they are Prime (True) or not (False).

{1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, \
2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, \
317811, 514229, 832040, 1346269, 2178309, 3524578, 5702887, 9227465, \
14930352, 24157817, 39088169, 63245986, 102334155, 165580141, \
267914296, 433494437, 701408733, 1134903170, 1836311903, 2971215073, \
4807526976, 7778742049, 12586269025, 20365011074, 32951280099, \
53316291173, 86267571272, 139583862445, 225851433717, 365435296162, \
591286729879, 956722026041, 1548008755920, 2504730781961, \
4052739537881, 6557470319842, 10610209857723, 17167680177565, \
27777890035288, 44945570212853, 72723460248141, 117669030460994, \
190392490709135, 308061521170129, 498454011879264, 806515533049393, \
1304969544928657, 2111485077978050, 3416454622906707, \
5527939700884757, 8944394323791464, 14472334024676221, \
23416728348467685, 37889062373143906, 61305790721611591, \
99194853094755497, 160500643816367088, 259695496911122585, \
420196140727489673, 679891637638612258, 1100087778366101931, \
1779979416004714189, 2880067194370816120, 4660046610375530309, \
7540113804746346429, 12200160415121876738, 19740274219868223167, \
31940434634990099905, 51680708854858323072, 83621143489848422977, \
135301852344706746049, 218922995834555169026, 354224848179261915075, \
573147844013817084101, 927372692193078999176, 1500520536206896083277, \
2427893228399975082453, 3928413764606871165730, \
6356306993006846248183, 10284720757613717413913, \
16641027750620563662096, 26925748508234281076009, \
43566776258854844738105, 70492524767089125814114, \
114059301025943970552219, 184551825793033096366333, \
298611126818977066918552, 483162952612010163284885, \
781774079430987230203437, 1264937032042997393488322, \
2046711111473984623691759, 3311648143516982017180081, \
5358359254990966640871840, 8670007398507948658051921, \
14028366653498915298923761, 22698374052006863956975682, \
36726740705505779255899443, 59425114757512643212875125, \
96151855463018422468774568, 155576970220531065681649693, \
251728825683549488150424261, 407305795904080553832073954, \
659034621587630041982498215, 1066340417491710595814572169, \
1725375039079340637797070384, 2791715456571051233611642553, \
4517090495650391871408712937, 7308805952221443105020355490, \
11825896447871834976429068427, 19134702400093278081449423917, \
30960598847965113057878492344, 50095301248058391139327916261, \
81055900096023504197206408605, 131151201344081895336534324866, \
212207101440105399533740733471, 343358302784187294870275058337, \
555565404224292694404015791808, 898923707008479989274290850145, \
1454489111232772683678306641953, 2353412818241252672952597492098, \
3807901929474025356630904134051, 6161314747715278029583501626149, \
9969216677189303386214405760200, 16130531424904581415797907386349, \
26099748102093884802012313146549, 42230279526998466217810220532898, \
68330027629092351019822533679447, 110560307156090817237632754212345, \
178890334785183168257455287891792, 289450641941273985495088042104137, \
468340976726457153752543329995929, 757791618667731139247631372100066, \
1226132595394188293000174702095995, \
1983924214061919432247806074196061, \
3210056809456107725247980776292056, \
5193981023518027157495786850488117, \
8404037832974134882743767626780173, \
13598018856492162040239554477268290, \
22002056689466296922983322104048463, \
35600075545958458963222876581316753, \
57602132235424755886206198685365216, \
93202207781383214849429075266681969, \
150804340016807970735635273952047185, \
244006547798191185585064349218729154, \
394810887814999156320699623170776339, \
638817435613190341905763972389505493, \
1033628323428189498226463595560281832, \
1672445759041379840132227567949787325, \
2706074082469569338358691163510069157, \
4378519841510949178490918731459856482, \
7084593923980518516849609894969925639, \
11463113765491467695340528626429782121, \
18547707689471986212190138521399707760, \
30010821454963453907530667147829489881, \
48558529144435440119720805669229197641, \
78569350599398894027251472817058687522, \
127127879743834334146972278486287885163, \
205697230343233228174223751303346572685, \
332825110087067562321196029789634457848, \
538522340430300790495419781092981030533, \
871347450517368352816615810882615488381, \
1409869790947669143312035591975596518914, \
2281217241465037496128651402858212007295, \
3691087032412706639440686994833808526209, \
5972304273877744135569338397692020533504, \
9663391306290450775010025392525829059713, \
15635695580168194910579363790217849593217, \
25299086886458645685589389182743678652930, \
40934782466626840596168752972961528246147, \
66233869353085486281758142155705206899077, \
107168651819712326877926895128666735145224, \
173402521172797813159685037284371942044301, \
280571172992510140037611932413038677189525}

{False, False, True, True, True, False, True, False, False, False, \
True, False, True, False, False, False, True, False, False, False, \
False, False, True, False, False, False, False, False, True, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, True, False, False, False, True, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, True, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
True, False, False, False, False, False, True, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False, \
False, False, False, False, False, False, False, False, False, False}

Special Projects

Still Even More on the Golden Ratio

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The well-known Fibonacci sequence formed by summing consecutive terms looks like:

1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89……….

And a well known property of this sequence is that if you take the ratio of consecutive terms you get closer and closer to the Golden Ratio the higher up the sequence you go. So if we divide 89 by 55 we get 1.61818181…….

We can create a Fibonacci series incorporating the variable x in the following way:

1, x, (1+x), (1+2x), (2+3x), (3+5x), (5+8x), (8+13x)…

Now a remarkable property of this sequence is that once again, if we take the ratio of consective terms in the sequence, we get the Golden Ratio – Phi – provided x=Phi, which I think is a remarkable result.

What this means is that looking at the sequence with Phi replacing x we get:

1, Phi, (1 + Phi), (1 + 2*Phi), (2 + 3*Phi), (3 + 5*Phi)…

And if taking the ratio of consective terms gives us Phi, this means that:

(1 + Phi) = Phi^2

(1 + 2*Phi) = Phi^3

(2 + 3*Phi) = Phi^4

The first result comes directly from the basic definition of Phi itself, namely that (1 + Phi)/Phi = Phi

Taking a deeper look at the above sequence I was able to come up with a general result, namely:

Phi^n + 2*Phi^(n+1) = Phi^(n+3)