New Mandate: 46.8 Degrees; due Januray 17th, 2010
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From: Bowser on 14 Dec 2009 07:57 "Robert Coe" <bob(a)1776.COM> wrote in message news:h6rai5t1436uf83abmdi9aq3qgpvre71d5(a)4ax.com... > On Mon, 14 Dec 2009 07:28:43 +1000, Troy Piggins <usenet-0912(a)piggo.com> > wrote: > : * tony cooper wrote : > : > On Sun, 13 Dec 2009 11:44:50 -0500, Bowser <Canon(a)Nikon.Panny> wrote: > : > > : >>OK, here's the new mandate for the Shoot In, due January 17th, 2010. > : >>Let's simplify things this month. Drag out those 50mm primes and shoot > : >>a pic using nothing but that, or whatever lens you have that provides > : >>the equivilant angle of view of, yes, 46.8 degrees. Use a zoom if you > : >>like, but lock it at "50." Fire at will... > : >> > : >>http://www.pbase.com/shootin/468_degrees > : >> > : >>http://www.pbase.com/shootin/rulzpage > : > > : > I don't understand. I had prime lenses when I was shooting film, but > : > all I have now are zoom lenses including an 18/55. Does that mean I > : > shoot at 50? > : > > : > Does it mean no cropping? Just resizing? > : > : Yeah mate, challenge yourself. As Bowser said, lock the zoom at > : 50 (or crop equiv) and no cropping. :) > > I don't believe he said no cropping. Crop as long as the angle of view of the final shot is around 46.8 degrees. The mandate is looking for shots taken at a "normal" angle of view.
From: Robert Spanjaard on 14 Dec 2009 10:54 On Sun, 13 Dec 2009 19:15:50 -0700, Russell D. wrote: >> Well... I'm not going to participate, because I probably won't shoot >> much the next couple of weeks. But I did shoot at a fair last August, >> and for that I only brought my Sigma 30mm F/1.4 (because of the neutral >> perspective and the large aperture). >> >> BTW, number 4 and 5 are deliberately out of focus. :-) >> >> http://www.arumes.com/temp/kermis2009/ >> >> > Nice. I like those. It would be nice to see some EXIF data unless it's > top secret. I just enabled the option to open the images in a new window (right mouse button). Or, to make it easier: http://www.arumes.com/temp/kermis2009/images.zip [811 kB] -- Regards, Robert http://www.arumes.com
From: Handy Andy on 14 Dec 2009 13:57 On Mon, 14 Dec 2009 07:53:19 -0500, "Bowser" <its(a)bowzah.ukme> wrote: > > >"Michael Benveniste" <mhb(a)murkyether.com> wrote in message >news:vn1bi5djg32mvvmg2ifav1vleira9b20ge(a)4ax.com... >> On Sun, 13 Dec 2009 14:41:52 -0500, Bowser <Canon(a)Nikon.Panny> wrote: >> >>>Damn shame. According to Big Bob's angle of view calculator, they >>>should be 46.8: >>> >>>http://www.bobatkins.com/photography/technical/field_of_view.html >> >> And that's correct, _if_ most nominal 50mm lenses were actually 50mm. >> But they aren't for reasons dating back to the rangefinder era. >> >>>I strongly suggest you dump all the sub-standard gear, get a 5D II >>>along with a 50mm 1.4 Canon lens and then you can enter the >>>"competition." >> >> I doubt it would help. It's actually because of Canon (and indirectly >> Leica) that Nikon's 50mm lenses are designed to have a focal length of >> 51.6mm. >> >> Of course, had Nikon done it "right," their 50mm lenses would have had >> a focal length of 52.3mm to match that of Contax/Zeiss. > >I had no idea this mandate could be so complicated. > >> >>>OK, how about 46.8 degrees plus or minus 5 degrees? >> >> 3 digit precision +/- 10 percent. Sounds about right. That may even >> cover the shift in focal length with focus distance found in most >> modern lenses... > >Damned modern lenses. > If using any CHDK capable P&S camera with a 36-432mm zoom with 129 (0-128) reproducible steps, just run this simple script on start-up. Or enable "Script Autostart" from the scripting parameters menu to "Once" or "On", so it runs automatically for you on power-up. ==========copy below this line========= @title Set-Zoom @param a StartZoom (22=50mm) @default a 22 set_zoom a exit_alt end ==========copy above this line========= Save as filename, something like, "DfltZoom.bas" [Using this uBASIC method (super-simple example above) you have a nearly infinite number of custom start-up shooting modes at your disposal. You can also save your most favorite defaults right along with a more universal script that sets up to 26 camera parameters for you (i.e. custom colors, focus, apertures, shutter speeds, bracketing methods, Hyperfocal settings, ISOs, Custom Curves, etc. etc.). See this page for a more complete list of all the user configurable camera parameters <http://chdk.wikia.com/wiki/UBASIC/TutorialScratchpad> But it goes much further than that if you get into Lua programming and/or using the set_prop commands to control your camera.] If unsure of your CHDK camera's 35mm equivalent zoom steps and related "set_zoom" numerical values, then you can run this script beforehand to find them. ==========copy below this line========= @title Zoom Stepping @param a Zoom step @default a 3 @param b Max zoom (A: 8/14) (S: 128) @default b 128 @param c Zoom speed: 1-10 (S-only) @default c 10 if a<1 then a=1 if a>b then a=1 if b<8 then b=8 if c<1 then c=5 if b>128 then b=128 if c>10 then c=10 c=c*10 get_zoom z set_zoom_speed c print "Up = Zoom In" print "Down = Zoom Out" print "L/R = Change Step" print "Step= ", a ,"No.=" z :loop wait_click is_key k "up" if k=1 then goto "raise" is_key l "down" if l=1 then goto "lower" is_key m "right" if m=1 then goto "stepu" is_key n "left" if n=1 then goto "stepd" goto "loop" end :raise set_zoom_speed c sleep 20 get_zoom z z=z+a set_zoom z sleep 100 goto "loop" return :lower set_zoom_speed c sleep 20 get_zoom z z=z-a set_zoom z sleep 100 goto "loop" return :stepd a=a-1 if a<1 then a=1 if a>b then a=1 cls print "Up = Zoom In" print "Down = Zoom Out" print "L/R = Change Step" print "Step= ", a ,"No.=" z goto "loop" return :stepu a=a+1 if a<1 then a=1 if a>b then a=1 cls print "Up = Zoom In" print "Down = Zoom Out" print "L/R = Change Step" print "Step= ", a ,"No.=" z goto "loop" return ==========copy above this line========= Note: with this script, that the zoom focal-length setting value ("No.=") only gets refreshed on your EVF/LCD display after you change the zoom-step increment ("Step="). A minor bug I'm not willing to take the time to find nor fix. This script wasn't really meant for this purpose. I only threw in the "print ... 'No.=' z" command for a quick cross-reference check. After you have changed to a zoom-step value of 1 by using your right/left directional buttons, then use the up and down directional buttons to change to a new zoom focal-length setting. The resulting 35mm equivalent value is displayed in your EVF if you have the Misc. Values for 35mm-equivalent zoom turned on. (OSD Parameters > Misc. Values > Show Zoom ON > Show Zoom Value as EFL) Then you can see exactly what 35mm focal-length you are working with. Toggle the left and right buttons once to go from a zoom-step of 1 to 2 and back to 1. Then it will refresh the zoom No. value on your screen. After you have found that number for your desired 35mm-equivalent focal-length, then plug it into the aforementioned script as a default zoom value to use every time you power up your camera. (Where 22 is now being defined as the default.) You can also find those values without this more convoluted script by just setting your camera to 50mm EFL, then go back into your CHDK menus and change that "Show Zoom Value As" to the "X" option. That also returns which numeric hardware zoom-step value is equivalent. Due to the vast number of camera models now supported by CHDK and all their varying lens designs and zoom ranges, there is no archive of "set_zoom x" = 35mm-equivalent number-list references anywhere on the net for each model number. Since each person can do this for themself there really is no need to provide that. In fact, a simple script can do all that for you. And if you use the "printscreen filename" command it will even spit out all the stepper-motor values and EFL values to a text file for you on your SD card. You can of course just use the EFL number being displayed on your screen and do without all this. But the zoom toggle on some cameras is touchy and it may take a few taps of it to get your camera's lens to exactly 50mm EFL each time.
From: Troy Piggins on 14 Dec 2009 15:14 * Calvin Sambrook wrote : > "Calvin Sambrook" <csambrook(a)bigfoot.com> wrote in message > news:hg411a$unj$1(a)news.eternal-september.org... > [---=| Quote block shrinked by t-prot: 24 lines snipped |=---] >> ray trace diagram at the moment I think I'll accept you are right. Maybe >> tomorrow I'll draw it all out to get my head around it properly! >> >> Sorry, time for bed I think. > > Isn't it amazing how much clearer things can seem after a good night's > sleep. Apart from the fact that I swapped my longer and shorter focal > lengths and so got it exactly wrong (duh) I was also confusing angle of view > with field of view. Andrey Tarasevich, in another post, covers the details > very clearly so I won't repeat them here except to say that of course Alan > was correct. Sorry. Worse that that - I was so out of it I defended you, justified that you were right, and made the same incorrect swap of focal lengths. Man, can't wait for Christmas hols... -- Troy Piggins
From: Troy Piggins on 14 Dec 2009 15:17
* tony cooper wrote : > On Mon, 14 Dec 2009 08:02:08 -0500, "Bowser" <its(a)bowzah.ukme> wrote: > > [---=| Quote block shrinked by t-prot: 11 lines snipped |=---] >> >>BS. You're just pissed because Tiger wasn't sharing with you, after all >>you've done for him. Lock that zoom near 50, shoot something, and send it >>in. No excuses. Golf is done forever. Elin isn't wearing her wedding ring >>any more, and the universe is upside down. So go shoot. > > Tiger, as you might know, lives in this area. Not my neighborhood, > but in the area. I'd need a wide angle lens, or maybe have to do a > panorama, to take a shot of the media trucks parked outside of the > gated community in which he lives. If you get a shot of Tiger with one of his mistresses using a 50mm lens, you win the mandate. -- Troy Piggins |