Motion blur problem

Q

qap15

Well-known member
I have been shooting a soccer tournerment for the past three weeks in bright daylight without any problem at all. Now on my last day i notice that the camera is producing blur when panning. the camera settings are 720, 50p shutter 1/500 focus on manual. why is this happening?

I don't know whether blur or out of focus is the correct description of what i experienced, but this only happened during panning.
 
Most likely you are panning too fast to hold detail. The golden rule of thumb for 24P ( 1/48th of sec shutter ) is that it should take 7 seconds for any visible object to cross from one edge of the frame to the other edge.

I don't know how 50P at 1/500 sec shutter changes this rule, but it's possible that with a fast pan there is just too much detail for the AVCHD CODEC to record at 21-24 Mbits/sec. ( assuming that you are recording in PH mode )
 
TheDingo, why is it doing it now? i have been shooting with same settings for the last three weeks without this problem. The 720, 50P setting i got from recommedetions here at DVXuser for sports events, while the 1/500 shutter speed comes from some BBC test recommendation on the HMC 151E i found somewhere in the internet.
 
If you weren't having this problem using the same camera and settings before, then you've either overlooked something or your camera needs repair.
 
I hope i have overlooked something, I hate camera repairs, my DVX100 cameback with sound problem cracking sound whenever you touch the volume adjustment nobes after repair, the GH2 changes focus zoom mode by itself without touching any button "so god help me" that this is not a repair case.
 
Can you post a clip? Odd that it would start three weeks in. You aren't panning any faster than before? 500 is fairly high shutter speed. I use 120 with 60P. 100 or 150 would be my recommendation with 50P.
 
There should be no blur with those settings at all, should be very sharp, check your settings
 
After several tests, it seems that Damwa is right. I did take the DVX100 and tried the same kind of panning and it had the same blur or lose focus, the GH2 did the same and i was getting mad to why i had not noticed this before, and on discovering the culprit i felt like a fool. The new Marshall LCD50 i got recently, shows details which the attached screens in all the three cameras don't clearly show. So is it right to say that panning generates some amounts of blur/reduces focus however small the movement might be?
Three days of torture trying to get to terms with a problem which was never there at all, a lesson learned, thanks all for your help.
 
How close are you zooming in? Maybe you could minimize the problem by zooming out a bit so you don't have to pan quite so much. I shoot a lot of soccer, and that is what I try to do.
 
This is more of a gut feeling than something I've tested, but I've been doing extensive VFX work with 150 footage this summer... and fast pans or zooms really seem to break up the codec. Freeze framing on well-lit footage with a whip pan or a crash zoom - it can get really blocky for a several frames.

The pan-speed rule of thumb is handy to have, but sometimes the action being filmed or the feel you want trumps that. I like a good whip-pan every now and then...
 
24p (1/48 shutter) with a fast pan will give you a strobing effect. High shutters on the other hand will give you a stuttery effect. (saving Private Ryan look). That's why I would suggest 100 or 150 shutter, or at the most, 300. Just use a multiple of 50 since you are shooting 50P and dial it in till you get the desired look.

Also, high detail settings can make the above more noticeable.
 
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