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RHKFilm
2007 November 17th, 11:23
Hi,

I extracted these stills from HV20 video. The professional photographers couldn't seem to catch the lightning but I sure did.

http://www.hv20.info/yopu/thunder00.png
http://www.hv20.info/yopu/thunder01.png

It was quite a storm shortly after these were taken.

-Robert

Rikki
2007 November 17th, 11:50
Its fairly tricky to catch lightning at the best of times and during the day even harder, but props to you and the HV20 for a job well done :D

kyle.presley
2007 November 17th, 12:37
Very cool, mate!

Ten Ounce
2007 November 17th, 13:13
That second picture of the lightning looked pretty wicked! Great job.

stanswx
2007 November 17th, 13:35
Those shots are very promising and exciting for me! I just got my HV20 yesterday and I can't wait to shoot some storms with it. Keep them coming man!

PK Gillock
2007 November 17th, 23:21
Great shots!

What's that guy looking at in the last pic? Obviously the smartest one there had the HV20 and was looking in the right direction. lol

nzo
2007 November 18th, 02:30
Wow! Pretty amazing Robert, especially the second shot, literally full of power.

I once tried to capture lightning using a point-and-shoot cam. Out of some 200 snaps I got one good one. Considering shutter lag and my reflexes, that wasn't too bad :)

Frank
2007 November 18th, 03:10
Interesting; someone over at DVXUser speculated that the HV20's rolling shutter wouldn't be able to capture a full lightning strike since it captures progressively instead of globally, but these pics give the lie to that notion.

They look spectacular, btw.

RHKFilm
2007 November 18th, 06:07
What you don't see in my photo is the tent with 200 people directly behind me. When the rain hit it caused the water to puddle and all of the female wedding guests to abandon their shoes. It felt like a scene from Final Destination with the lightning getting ever closer to our gigantic tent which also had electrical cables running through the standing water. My father and I rode the storm out in his car white-knuckled watching the tent. Luckily, lightning stayed in front of the camera that day.

As for the rolling shutter, I did get a couple of odd frame grabs with lightning that look like the camera adjusted exposure part way through the frame. Here is an example:
http://www.hv20.info/yopu/thunder04.png
Is this the rolling shutter people were reporting?

Unfortunately I didn't reverse the pull-down on this 24p footage so there are more examples but they are interlaced.. none as impressive as the original postings. Just glad I got the big ones nice and clear.

I realize now I should've named them "lightning" instead of thunder.
Robert

Frank
2007 November 18th, 12:48
People weren't reporting it, they were just speculating. Basically it was part of a discussion back in June/July about rolling shutter, mostly by people who hadn't used the HV20 and partly based on the infamous helicopter footage.

That frame grab looks like it could be what they were afraid of, although there is a very clear demarcation between the top half and bottom, as though the frame was exposed in two parts. I would have expected rolling shutter to cause a more gradual shift from top to bottom.

Michael Bath
2007 November 30th, 05:55
Hi Robert and all - wondering what recording settings you used for that lightning footage and the program used to extract the stills ?

I've recently purchased the PAL version of the HV20 for storm chasing and finally had a chance to see how it goes with lightning. In the past I had not been fussed with video stills of lightning due to the small image size from DV, but the HD is a big improvement so am keen to get some decent grabs now and then.

I used Premiere CS3 to capture in 1080p25 and have exported every frame of two separate lightning flashes. The results are available here:

http://australiasevereweather.com/video/stills/2007/2007112301.html

http://australiasevereweather.com/video/thumbs/2007/1123mb02.jpg

http://australiasevereweather.com/video/stills/2007/2007112302.html

http://australiasevereweather.com/video/thumbs/2007/1123mb22.jpg


I was a bit disappointed to see half captured lightning bolts and 'rolling shutter' forum members have referred to in this thread.

Is there a trick to capturing lightning with the HV20 ?

regards, Michael

w.pasman
2007 November 30th, 08:41
Strictly the rolling shutter should be applied when in interlacing mode but not when in progressive mode. So if canon implemented it all correctly, shooting in 24p or 25p should avoid the rolling shutter while shooting in 50i or 60i should give you rolling shutter.

w.pasman
2007 November 30th, 08:45
http://www.hv20.info/yopu/thunder04.png
Is this the rolling shutter people were reporting?

I thought you said that you shot 24p? In that case you should not have a rolling shutter.

My first guess would be that the extra light you see in the top half is caused by cross talk from the intensely exposed pixels in the top half. Notice that the change in background lightness occurs exactly at the height where the lighting is cut off by the head.

Michael Bath
2007 December 6th, 19:55
I worked out what I was doing wrong - needed to record in 25 fps progressive, not just HD ! Very happy with the frame grabs - a few samples :

http://australiasevereweather.com/video/thumbs/2007/1204mb02.jpg (http://australiasevereweather.com/video/stills/2007/1204mb02.jpg)

http://australiasevereweather.com/video/thumbs/2007/1204mb19.jpg (http://australiasevereweather.com/video/stills/2007/1204mb19.jpg)

http://australiasevereweather.com/video/thumbs/2007/1204mb27.jpg (http://australiasevereweather.com/video/stills/2007/1204mb27.jpg)

http://australiasevereweather.com/video/thumbs/2007/1204mb28.jpg (http://australiasevereweather.com/video/stills/2007/1204mb28.jpg)


regards, Michael