View Full Version : GY-HM70 for sports


Anthony Lelli
August 4th, 2015, 11:38 PM
Ive been shooting soccer games with the X70 for a year now (and XA20 and AX100 before that) and last week I switched to the JVC HM70 because I had to cover 2 consecutive games (about 4hrs and change in total) , since the JVC has 2 batteries and other things ...

Anyway the camera did great for the first game in a bright sunny day, no problem pushing the shutter speed (it doesn't have ND). Footage in 1080p60 @28Mbps came out a bit better than the Sony X70 in HD, but in the same league to be honest.

Few things happened during the second game under the stadium lights at night. For the friends here I'd like to share because it was unexpected , so we all can be prepared and adjust in a similar shooting.

Being the only camera , this kind of coverage requires lots of zoom in and out and a pretty fast shutter speed, so the performance of the camera under high gain is to the limit.

at 1.2 the HM70 is superb (way better than the Zeiss of the Sony X70) , but the action of the zoom stops down the aperture pretty quickly. To cut the story short 1.2 can't be used because the moment you zoom in the aperture changes dramatically (and it shows). In comparison the Sony X70 also stops down zooming but it will be nowhere near to the sudden changes of the JVC.

Again I had no problem with the high gain (the noise is more like salt&pepper, pretty good). The problem was with the sudden changes in brightness zooming in and out due to the aperture that can go from f/1.2 to 5.6 making a big difference in brightness.

After 15 minutes I've decided to lock the max aperture at F/2 (avoiding the 1.2 and 1.6). After that the aperture changes zooming was much smoother also giving to the auto gain more time to settle. In the end @F/2 max the footage was similar to the Sony

A final note about the auto gain : it's slow, doesn't react in time to compensate for sudden changes of both the aperture or the brightness (or darkness) of the scene. Since the HM70 doesn't give gain control (it's only AUTO) then we must work around it to prevent mistakes.

We must produce with what we have, and try to find workarounds. complaining about it won't make anything better. And with a simple lock @F/2 the camera will deliver.