Not my best photography ever but I learnt a lot from this mornings mini test on the footbridge over Woodside Locks.
Part of the reason for venturing out this morning was to scratch an itch and also to test a new filter. It had to be done very early (I was out well before 7am) to ensure I didn’t get in anyones way as this towpath is popular with cyclists, joggers and dog walkers at almost all times of day.
I fully understand the concept of ND filters for the drone, especially in controlling shutter speeds for smooth video, but have been surprised to see advertisements for ten-stop ND filters which can extend exposure times into the seconds even in bright sunshine. As drone photographers we tend to keep our ISO at the lowest possible setting but even at 100 ISO and on an overcast morning in the shade of some trees I was getting eight seconds this morning. I could have pushed the ISO up and reduced the shutter speed but the purpose of today was to learn rather than create an image for the wall.
As you can see from the image above, the drone was no more than seven feet above the bridge over the lock with trees encroaching to within the same distance from above, behind and the right. The morning breeze combined with the downdraft from the drone in such a confined space meant it was struggling to remain perfectly still; indeed I was surprised at how buffeted I was stood below and slightly to the drones right.
An eight second exposure was probably a lot to ask in these conditions! I knew it would be tight under the trees, I’d even put the drone into Tripod mode to ease it gently in to the space, but had not really appreciated quite how much wind turbulence there would be.
A healthy dose of the shake reduction filter in Photoshop has produced an image that confirms the filter is neutral, and that given the right circumstances it should be more than practical to use slow shutter speeds in daylight to achieve a perfectly acceptable long-exposure from the air. To be fair I could have increased the ISO and thereby increased the shutter speed to 2 or 4 seconds for example, but this was after all just a quick experiment to see whether the new filter lived up to the good reviews I’d read online and to prove that the drone could hold still enough for a longer exposure.
I’m convinced that in a better environment I will be able to capture some interesting and creative images with the drone. I probably need to avoid hovering in what was effectively a wind tunnel next time! Mind you, that won’t stop me trying this again with a shutter speed of 2-4 seconds to see if that helps.
FREEWELL ND1000
The filter I was using this morning is a Freewell FW-MAV-ND1000 Filter. It fits snugly and easily and is also straightforward to remove afterwards yet still feels very secure on the lens. Drone start-up and gimbal calibration was not affected and the files have no appreciable colour cast in the test shots I took this morning returning an image with the same colours compared to shots from the same basic area and height but with no filter attached.
Dave's Place 
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