Pro video blog…Produced by Philip Johnston DoP/Editor

ex3-side11I still do not know what the answer is to this problem but I would like to share a word of warning…I was filming yesterday and choose to film in SP 1080i mode as I had a 12 hour day. Now as we all know we do not film 12 hours of material in a 12 hour day but those precious 22 extra minutes per 16Gig card can be useful.

Now why did I choose 1080i and not 720p well firstly there is a lot of action footage and the final production ends up on SD DVD and watched mainly in the UK. A rule of thumb for filming in HD is as follows…

1. End result = DVD = interlace

2. End result = web = progressive

So I stupidly choose SP mode instead of HQ mode to “save on card space”. My 16G cards being SDHC Transend cards for archive purposes as this job will not be completed till sometime in July. So you start to see the picture…I was saving card space when I had at least three 16G SDHC cards with me and even at full HD would not fill 3 cards. 

So as they say in the good old Indiana Jones films “You choose badly”…why. I have an Apple Mac Pro with an AJA io HD box so I can afford to start with the best setting and down convert later if needed. 

To get to the point I was reviewing some of yesterdays shots and it came to the canoe section when I noticed square pixel boxing all over the water shots to be fair this will not be seen by the time it gets to an SD DVD but it’s there all the same. I have not experienced this before but I also have a nagging doubt that it may also be the cards fault as well.

In my own Sherlock fashon I took things back to basics and tried to re-create the problem without success…I filmed a sink of water at 1440 and 1920 but both looked fine although the 1920 was crisper looking as you would expect, but no blocking.

Fortunately 99% of the footage is fine and it spans 2h 24m using 3 cards I had forgot I had used 20mins of one of the cards last week. So my advice is as follows…

1. Only choose HQ mode for filming with the EX1, EX3

2. Web based productions look better shot with 720P 50

3. TV and DVD based productions look better with motion shot on 1920 x 1080i 50

4. If like me you need archive where the SxS card becomes a pain only use Transend Class 6 SDHC or Panasonic Class 10 SDHC cards.

My conclusions…

I doubt if this was card problems as the rest of the footage is fine and the SDHC card is only a problem if you are using over cranking as they do not work in this mode. You do not get a choice of HQ and SD for the sake of it…HQ gives you the best quality so don’t compromise for the sake of a £40 SDHC card !

UPDATE…It’s not a card problem it’s the technology, seemingly moving water is very hard for digital to understand and compresses it into wee square boxes, you only see this effect when you have moving water. I filmed further test footage this morning and it did not matter a hoot wether it was on HQ or SQ mode and I also filmed onto Sony SxS and SDHC both the same quality…though the HQ pictures were much punchier.

I have to admit I have not filmed a lot of water shots with this camera so I was caught out when I suddenly saw the square boxes in the moving water but as I can do nothing about it I will avoid filming water sports in the future. The best part about video is that you never stop learning.




Having been working in the video business since 1988 I have amassed a great amount of knowledge of both the kit and production values over the last 30 years.

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