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  1. #91
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    I'd still be curious if the picture was taken in portrait or landscape. Not commonly known, but dSLRs still have a moving curtain which doesn't take the entire frame of the picture at once. If the camera is held in a portrait stance (vertically), the shutter will move from one side to the other over the time period.

    Second, with a flash and a lower shutter speed, you will indeed get a potential multiple-exposure sequence - the one exposure where the flash illuminated the subject area enough and the second where the item being photographed was bright enough to register based on the ISO sensitivity.

    An interesting side effect is to do the opposite. I took a picture at Epcot Disney outside the French area and it was chalk full of people walking to and fro... did a very low ISO setting and ultra-long exposure and showed my kids the magic of disappearing people!

    Edit: Check out https://www.youtube.com/watch?v=CmjeCchGRQo at the 2:32 mark... you'll see what I mean on the shutter movement.
    Last edited by djeuch; 01-20-2017 at 12:26 AM.
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  2. #92
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    Sorry, I don't buy your explanation at all. The picture is the effect of the camera flash and the shutter speed and the distance the camera was from the pistol when this picture was taken. The light from the flash hit the pistol just before the hammer struck the firing pin. Immediately after the light reflected off of the pistol, the cartridge fired, the bullet left the barrel, and the light generated from the flame from the hot gases that propelled the bullet followed directly behind the light from the flash that reflected off the pistol and a portion of that light from the hot gasses entered the aperture before the shutter closed. The hammer appears back because that was the position of the hammer when the light from the flash reflected off of it. The light from the hot gasses of the burnt powder happened immediately after, but a portion of that light made it past the shutter before it closed.

    All in all, a well timed photo. Bravo, probably one in a million from a standard camera setup!
    Last edited by Nowhereman; 01-20-2017 at 12:36 AM.
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  3. #93
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    Quote Originally Posted by djeuch View Post
    I'd still be curious if the picture was taken in portrait or landscape. Not commonly known, but dSLRs still have a moving curtain which doesn't take the entire frame of the picture at once. If the camera is held in a portrait stance (vertically), the shutter will move from one side to the other over the time period.
    I did not know that. Interesting information!

    The metadata says:

    Orientation: Horizontal (normal.)

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  5. #94
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    Quote Originally Posted by orfeo View Post
    Okay. . . I guess everyone's had a chance to weigh-in on this before I put forth my own opinion as promised. Forgive me if I don't explain my theory perfectly though, and try to bear with me as best you can:

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    The above four people seem to be in a similar camp as I am on this.

    I think it's the firing pin. When I first considered that, I didn't really want to believe it because I didn't think the FP had enough mass. But in fact, it weighs 113.6 grains (about as much as a 115 grain bullet). The hammer hits the firing pin and then stops against the slide while the firing pin continues some distance under it's own inertia, against the force of the firing pin spring, to exit the firing-pin-hole in the breechface and strike the primer. The explosion then causes the case-head (the base of the cartridge case) to slam back against the firing pin first due to head-space (the allowance between the case-head and the breechface) and then into the breechface itself. At the same time that the case-head is slamming the firing pin backwards, the firing pin spring is starting out compressed and wanting to spring back. The heavy firing pin moves backwards with alot more force from the violent explosion than it had when it was moving forward from the hammer-strike. . . plus it now has no firing pin spring to dampen it's rearward travel before it strikes the hammer.

    I also think it's the slide-transmitted-shockwave. Another possible factor to induce the hammer going back is the fact that it is resting on the slide at the time of the case-head explosively slamming into the breechface. The shockwave traveling through the slide may also knock the hammer back (just like those desk toys with the hanging steel balls, where you let one swing into the group and the shockwave travels through the line of balls to only disturb the last ball at the other end). Actually, I think the shockwave alone could be enough to explain the hammer going back, even without the firing pin striking it.

    So there you have it. My very in-elegant explanation of my theory. Based upon almost a decade of consideration. . . I think it's either the firing pin striking the hammer, the slide-transmitted shockwave to the hammer, or more likely both factors together.

    BTW - Post # 43 was the first mention of the Firing Pin .Since the barrel hasn't unlocked , it's the only thing left that mechanically could overcome an 11 pound or so hammer spring and push the hammer back .

  6. #95
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    The only point of contact the firing pin would have is on the primer... and since the primer wasn't blown out the only other way to transfer any kinetic energy would be to move the mass of the slide. Also, slide-transmitted shockwave... is rather far fetched, I don't think the mechanical linkage of the barrel/slide/buffer spring/hammer/hammer spring would be able to efficiently transfer that much energy to knock the hammer that far back. Remember, if one of those hanging steel balls are out of alignment just a little, it doesn't work. But if you could convince your wife to allow you to strike the front of the barrel of her pistol with a hammer you might be able to test it.
    Last edited by Nowhereman; 01-20-2017 at 01:15 AM.

  7. #96
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    Quote Originally Posted by Nowhereman View Post
    The only point of contact the firing pin would have is on the primer... .
    Hmm ..... then what strikes the firing pin ?

  8. #97
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    I agree with the theory that the hammer being back is the result of the combination of flash exposure and the relatively long exposure duration. It is possible that the portrait orientation/shutter curtain travel contributed, but only if the camera was oriented in the right direction for the curtain to be traveling from the rear of the gun to the front.

    Unless intentionally set for rear curtain sync, the built in flash or a shoe mount flash on a D70 (or any DSLR with a FP shutter) will fire as soon as the front shutter curtain opens, as mentioned, at the beginning of the 1/125th of a second exposure. Additionally, odds are that the flash was fired in TTL mode, meaning that the camera fired the flash at a power level and duration just long enough to reach the correct exposure for the subject. This means that the time the flash was actually illuminating the subject was just a tiny fraction of the 1/125th of a second that the shutter was open.
    It does seem very likely that the state of the hammer (actually the whole gun and hands) was captured while it was falling, after the trigger was pulled and before the action cycled. The flash duration would have been short enough to have frozen the moving hammer with very little noticeable motion blur. Once the flash turned off, the only significant light to be recorded would have been from the fireball. Knowing the ISO and aperture the lens was set at would help confirm that it would have been too dark for much other movement to have been noticeable. Also if the photo was taken just as the the trigger broke, 1/125th of a second might have been short enough to have captured the image before the slide cycled anyway.

    In any case, I think the image is the result of the way flash photography works.

  9. #98
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    kneedeep, that's great information on the flash, that it illuminates only long enough to achieve correct exposure, only a tiny fraction of the 1/125th of a second total exposure.

    The metadata, which we can see thanks to the link Hexley provided, shows the F number was 6.3, while maximum possible aperture was 4.4.

    The background suggests to me that the gun would have been pretty dark the entire time the flash was off. So the picture is a clear picture of a hammer in the back position -- or you suggest an intermediate, moving position -- plus a fireball picture from the end of the 1/125th second exposure. Basically two time points were illuminated. An early one for the gun, and a late one for the self-illuminated fireball which did not need flash.

  10. #99
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    Is there a video camera that can do slow motion to see something like this in action? Larry Vickers has a YouTube channel that is the only one I know of that uses slow motion that doesn't annoy me because he doesn't use it for the sake of using it.
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  11. #100
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    Jerry Miculek has a lot of excellent high speed videos. He's always worth watching even when not having high speed video.

    Miculek does do it more for the visual than any vital reason of showing function, but it's pretty awesome.

    An example that shows the sequence of hammer, firing, slide movement, and hammer recocking very well is: https://www.youtube.com/watch?v=KXwLi3qKD0w&t=8s starting only a few seconds from the beginning.
    Last edited by trenace; 01-20-2017 at 02:20 AM.

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