haroldp Posted March 14, 2012 Share #61 Posted March 14, 2012 Advertisement (gone after registration) Yes! I remember that. Amazing stuff. That's where I learned with the unfortunate TC Contender to let the action seat the bullet into the lands. (Bullet was not crimped in, and extended a bit over a compressed load.) Not that it helped me shoot better! And I used a bench loader, measured ball powder carefully, used same weighted bullets.... but like using a Leica it did not make me a better shooter. Gosh I hated that weapon. Incidentally, this was in Roswell, New Mexico where wildcat rounds were always being made. But that's too OT. Oh, when I went to trade in my Super Blackhawk the dealer said, "This is the first flame-cut force cone I've ever seen on one of these" and gave me one heck of a good trade in. (Although you probably recall it was a real problem with the defunct 357 Super Magnum.) Never getting to Roswell, I only competed against earthlings. .... H Link to post Share on other sites More sharing options...
Advertisement Posted March 14, 2012 Posted March 14, 2012 Hi haroldp, Take a look here Taking pictures handheld; some neuromechanical aspects. I'm sure you'll find what you were looking for!
lars_bergquist Posted March 14, 2012 Share #62 Posted March 14, 2012 By nervously afflicted I hope you mean something like anxious. By your age I would think you have a tremor of some kind. No? Actually, no, except when I am quite tired. LB Link to post Share on other sites More sharing options...
lars_bergquist Posted March 14, 2012 Share #63 Posted March 14, 2012 Years ago I was a long-range metallic silhouette shooter. Our club did not permit prone shooting of any kind (good old New Mexico). Of course, the handguns had to have a lot of power to knock down the heavy iron targets, so recoil was an issue. The very worst handgun was the one which directed recoil straight back into the hand (the TC Contender). It would beat you up. Strangely, the best for me were the old Western six-shooter style revolvers. Fortunately, Leica shoters are not much bothered by recoil. It's different with Nikon. Once our camera club was visited by a Nikon rep person who demonstrated his superior gear. He was very contemptuous of other 'small' and presumably incompetent makers. So I took my Olympus OM-1, rested it on the palm of his outstretched hand and released the shutter with a wire release. It did not move. Then I did the same with the Nikon FM he was demonstrating. It fairly jumped. Nikon had relied on the sheer mass of the F cameras (by then, it was the F2) to damp out the mirror and shutter movement. The lightened camera was literally thrown about by these forces. Well, the man did shut up. Now let's return to the subject of this thread. LB Link to post Share on other sites More sharing options...
pgk Posted March 14, 2012 Share #64 Posted March 14, 2012 Now let's return to the subject of this thread. Alpa do make some interesting grips - ALPA of Switzerland - Manufacturers of remarkable cameras - ALPA 12 WA rosewood natural - somewhat 'anatomical', but the prices are high even by Leica standards. Still its an interesting area for investigation..... Link to post Share on other sites More sharing options...
Guest #12 Posted March 18, 2012 Share #65 Posted March 18, 2012 That is a whole new issue that is worth to study: the interplay between the properties of the tripod and the vibrations introduced by the camera (mirror and shutter). I've done some measurements and it appears that camera/tripod combinations have fundamental frequencies which are different around the three axes of rotation of the camera (yaw, pitch, roll). Those vibrations are often damped quite well. But if you have a shutter time that is in the neighbourhood of one swing of the camera in one of the modes of vibration, you have a problem. It appears that long exposures and very short ones are OK, but around 1/15 - 1/30 of a second can be a real problem, since the camera starts the vibration due to the mirror movement and/or shutter action and when the shutter is open, the tripod is really rotating. There is no time to wash out the effect as in long exposure times. With very short times, the tripod/camera combination has not started to rotate yet. This effect can be so dominant that an M9 on a 2000mm f/10 lens can not be used for astronomy on a very heavy tripod (20 kg). Surprising for a camera that has no mirror! Ofcourse 2000mm is very revealing. A Canon 5DII with liveview or mirror lockup gives no problems. Somewhere I have seen tests on damping in wood vs. other tripods. Did you test this chestnut? Link to post Share on other sites More sharing options...
Lindolfi Posted March 18, 2012 Author Share #66 Posted March 18, 2012 No, sorry, no chestnut. But I did compare alluminium Gitzo's against carbon Gitzo's and the latter were more damping (stopped earlier with wobbling after a perturbation) at the same stiffness. Link to post Share on other sites More sharing options...
haroldp Posted March 19, 2012 Share #67 Posted March 19, 2012 Advertisement (gone after registration) No, sorry, no chestnut. But I did compare alluminium Gitzo's against carbon Gitzo's and the latter were more damping (stopped earlier with wobbling after a perturbation) at the same stiffness. Damping factor is a known property of Carbon Fiber, which is what makes it so effective in applications like tennis rackets, golf clubs and tripods. Light weight is an added bonus. .. H Link to post Share on other sites More sharing options...
M9reno Posted March 19, 2012 Share #68 Posted March 19, 2012 As far as I can tell from a quick reading of this thread, reference has not yet been made to taking photographs with the self timer. I just tried this with the M9 yesterday, with very good effect. The two-second delay time option is perfect for handheld in low light. Keep your fingers still, and let the camera release the shutter on its own. Thanks for all the informative discussion in this thread, by the way. Link to post Share on other sites More sharing options...
tobey bilek Posted March 19, 2012 Share #69 Posted March 19, 2012 Leicaflex cameras have a cam mechanism that all but eliminates mirror slap. I don't know if R models kept this feature.[/quote R4 & R5 were cheapened and shook like crazy. R6 got the mirror dampener put back in and life was good again. 6,6.2, & 7 were fine cameras. As were my Leicaflex and SL. Link to post Share on other sites More sharing options...
pico Posted March 20, 2012 Share #70 Posted March 20, 2012 Damping factor is a known property of Carbon Fiber, which is what makes it so effective in applications like tennis rackets, golf clubs and tripods. I am still not fully informed of carbon fiber, having seen many different configurations of the material, its weave (or not), layering and so-forth. For example, some configurations have the virtue of strength while the front end of my old bike, which is CF has a warning that once involved in an accident, even if no damage can be seen, it must be replaced with a new one because its strength has probably been compromised. The same is true of the whole frame of my new bike - Madone 3, all CF. So whenever I handle a CF tripod I just don't know what I'm getting. A 'weave' type can be faked with a veneer. It would be good to have the manufacturers include some kind of vibration dampening metric in their literature. Or I should just get up the nerve to visit Stan Prosen, a local, and ... well, you can google him and carbon fiber. I'll stick to wood and aluminum (literally sticking to aluminum in the winter) Link to post Share on other sites More sharing options...
Lindolfi Posted March 20, 2012 Author Share #71 Posted March 20, 2012 Pico, interesting subject, the properties of carbon. It depends a lot in which the carbon fibers are embedded and their orientation. Carbon fibers themselves have very little damping, but the way the fibers are embedded in for instance epoxy may increase the damping. So in a carbon blade on which athletes like Oscar Pistorius run, you want little damping, but in a tripod you want a lot, without sacrificing strength. Without doing measurements you can just do a simple test with a tripod: place your camera with the longest lens on it that you want to use and attach a laser pointer. Fasten all axes. Tap the camera so that it starts to vibrate along the vertical axis (usually the less stiff rotation) and watch the laserpointer dot on the wall settle. The time it takes is an indication of damping if you have a given excursion of the dot at the start. Set up another tripod and compare. Link to post Share on other sites More sharing options...
pico Posted March 21, 2012 Share #72 Posted March 21, 2012 Pico, interesting subject, the properties of carbon. It depends a lot in which the carbon fibers are embedded and their orientation. Carbon fibers themselves have very little damping, but the way the fibers are embedded in for instance epoxy may increase the damping. So in a carbon blade on which athletes like Oscar Pistorius run, you want little damping, but in a tripod you want a lot, without sacrificing strength. Understood. For rough roads, I would choose an extruded aluminum frame with a lot of flex, something like the Biria step-through. The fully carbon bike is murder. Without doing measurements you can just do a simple test with a tripod: place your camera with the longest lens on it that you want to use and attach a laser pointer. Fasten all axes. Tap the camera so that it starts to vibrate along the vertical axis (usually the less stiff rotation) and watch the laserpointer dot on the wall settle. The time it takes is an indication of damping if you have a given excursion of the dot at the start. Set up another tripod and compare. Great idea and one I can perform in my back yard. I'll include an exposure in one of the measurements. Hasselblad w/500mm Tessar would be a good start. It might also demonstrate how much influence the mirror and rear shutter compare to a shot done with pre-fire. OMG, I also have a universal (iris type) lens holder and can put the laser in there for LF (Deardorff) experiments. Thank you very much. Such an elegant test. Tomorrow I'll shop for a good laser pointer. BTW - In an earlier post I put up a photo of my converted very large and heavy wooden surveyor's tripod. I believed for a long time it was superior for my heavy camera and then I found that almost all such tripods are now largely made of composites. But then again, surveyors use image stabilization and feedback from the target. No conclusion yet. Link to post Share on other sites More sharing options...
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