Thing will be using a slow shutter speed and a wide-open lens to compensate for the lack of light where she is shooting. Shutter spends more time taking the picture of the gun with the hammer cocked, so that shows up fairly well. Then the hammer drops and takes only a split-second as the round fires, giving you that nice burst of flame at the muzzle. The gun action works, leaving the hammer cocked again as the camera finishes taking the picture. There is a bit of blur there; this is from the time in which the action of the gun was actually operating.
If you are using a digital camera, try setting the "film speed" adjustment for something very low: 100 ASA or less, if you can. That will slow down even an automatic shutter so you should be able to start getting compressed motion.
I did some of this work several years ago, using an old Miranda 35mm and a Ricoh 120 twin-lens reflex, shooting at night in a dark gravel-pit. Set the shots up by the car's headlights, then adjusted camera for focus, adjusted the lens aperture for the amount of light indicated by the chart on the big flash, THEN set the shutter for half a second and doused the lights on the car. Camera shutters synchronise with the opening of the REAR screen on a focal-plane shutter, so the flash goes off the instant that the rear screen is fully open, lighting the subject who is holding the rifle; half a second later, the front screen closes, so you have half a second to play with. This is plenty, especially when you consider that the average person's reaction time is generally much less than HALF of this. So the camera button would be pressed, the rear shutter screen would go, the flash would pop, the shooter would see the flash and pull the trigger of the SAFN-49 which was loaded with very special .30-06 shells: light bullet and a charge of very slow powder. Cartridge would go "BANG!" and there would be about 4 feet of flame out the muzzle and a jet of flame coming up from the gas bleed and the red-hot casing would trace a path halfway to the ground. It was all very impressive...... and now you know how to do it for yourself.
One odd point is that the film, which was just the cheap 100 ASA stuff, would actually record MUCH more muzzle flash than the unaided eye could detect. I suspect that much the same thing is happening with this particular "telephone" which, right now, is taking pictures that a lot of pros would admire.
Very nice work!
DO hope your Fine Lady enjoyed her debut as a model! For photos like these, she deserves a nice dinner.
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