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Old 23rd October 2013, 10:37 AM
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Monty Monty is offline
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Originally Posted by Neil-T View Post
Hi Monty, not sure if its of any use, but the Nikon V1 and V2 series camera does not have a mechanical mirror, its a mirrorless camera, I think thats the reason I got the shot of Woddy's muzzle blast as I mistakenly left it on Electronic High shutter speed which does 60 FPS. Neil.
Hi Neil

the frame rate is not the problem it's the exposure time that is the critical factor. I can't remember for sure but I think the V1 in 60fps mode has an exposure time of around 1/250th to 1/125th of a second so whilst you're getting 7 times more frames per second than I can, the exposure time for each frame will be much, much longer than I can achieve with a fast flash. You would get a picture of muzzle blast for sure, but the pellet would have moved a few metres during the exposure time so you probably can't even see the 'ghost' of where it was. I suspect (as RobF has already said) that even an exposure time of 1/64000th of a second may be too long! We'll get some pretty cool muzzle blast shots but I'm desperately hoping to be able to see the pellet as well.

The aim is;
to shoot in darkness, therefore the camera shutter speed has no influence on the image other than the risk of sensor noise being introduced. A 2-5 second exposure is absolutely fine as long as it really is very dark.

Use a flash at the setting which gives the shortest possible duration (currently 1/64000th of a second) This becomes the 'shutter speed' as well as the light source

Set the aperture between f4 and f8 to give a reasonable depth of field. Might be able to squeeze f11 if I can bump ISO up enough.

Try to over expose the area that the pellet is likely to be by 1 or 2 stops. If it's a blur it'll be easier to see if it's over lit.

Forget about the camera being activated completely, the shutter is already open before we fire the shot and will remain open for a while after as well. It's set to fully manual so no auto focus, no light metering, no aperture selection etc. Shutter lag, exposure calculation, ability to press the release at the critical moment are now immaterial as the image is now managed entirely by the flash intensity and duration. The camera is the least important component as long as it has a full manual setting, a usuable focal length, high ISO capability and a remote release (so I can be well out of the way when the rifle goes off) and low sensor noise we could use almost anything, even a point and shoot. It doesn't even need to be compatible with the flash gun.

The flash is triggered by the sound of the sears/hammer/discharge via RobF's sound sensor gizmo. It has no lag other than the time it takes for the gizmo to respond and the capacitor to discharge. Hopefully this is really fast but will definately be much faster than the camera body.

Use a wide (ish) angle lens. Probably circa 24-28mm, possibly wider. Wide angle lenses are better at capturing fast objects and minimising motion blur due to the wider field of view

Avoid shooting the camera or lens. You think Daystate GP rifles and March scopes are expensive, think again! This would make me seriously unhappy
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Last edited by Monty; 23rd October 2013 at 12:09 PM.
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