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-   Sony HVR-Z1 / HDR-FX1 (https://www.dvinfo.net/forum/sony-hvr-z1-hdr-fx1/)
-   -   1/30th shutter on FX1? (https://www.dvinfo.net/forum/sony-hvr-z1-hdr-fx1/63024-1-30th-shutter-fx1.html)

Stephen Finton March 16th, 2006 05:29 PM

1/30th shutter on FX1?
 
Does it half the resolution like on SONY SD cams or is it full 1080i at 1/30th?

Boyd Ostroff March 16th, 2006 05:33 PM

According to Adam Wilt's review, it halves the vertical resolution in HDV mode, however you don't lose any quality in DV mode since downsampling is done after frame doubling, giving you 540 lines of vertical res. This is a handy way to gain an extra f-stop if shooting standard definition.

Chris Barcellos March 16th, 2006 07:30 PM

Quote:

Originally Posted by Boyd Ostroff
According to Adam Wilt's review, it halves the vertical resolution in HDV mode, however you don't lose any quality in DV mode since downsampling is done after frame doubling, giving you 540 lines of vertical res. This is a handy way to gain an extra f-stop if shooting standard definition.

Boyd:

So do I also lose vertical resolution at 1/15, or is it peculiar only to 1/30

Boyd Ostroff March 16th, 2006 07:55 PM

I believe the issue is that interlaced video is captured in two fields which each take 1/60 second. At 1/60 sec shutter speed (or higher) there's time for the shutter to open and close during each field's capture interval. But if your shutter speed is 1/30 sec then the same data will be written to each field. As I understand it, setting the shutter to 1/15 sec would result in the same data being written to both fields of two frames and they would also only have half the vertical resolution, but would have more motion blur.

Douglas Villalba March 16th, 2006 08:36 PM

Quote:

Originally Posted by Stephen Finton
Does it half the resolution like on SONY SD cams or is it full 1080i at 1/30th?

I believe that the previous answers are true for CF30 but are incorrect for 1/30 speed. At 1/30th you may get motion blur but if you have talking heads for example it actually looks more like film.
I actually started using it due to low light and I use it all the time to get that look of film.
In CF30 you due loose sharpness but it is still 1920X1080 so again if you are filming people it doesn't matter if it goes a little soft.

Here is a clip shot at 1/60th (I had to use diffusion in post because it was to sharp) http://www.dvtvproductions.com/MOVIE...ials/PIXYS.mov

Here is clip shot at 1/30th (the part inside the church is all 1/30th and some parts are also CF30 like the part with the mother of the bride sitting) http://www.dvtvproductions.com/MOVIE..._Sorenson3.mov

Boyd Ostroff March 17th, 2006 07:37 AM

From Adam Wilt's DV Magazine review of the Z1:

Quote:

As with other Sony models, slow shutters field-double, but the field-doubling happens in HD and the down-converted images suffer only a slight vertical resolution loss instead of a halving of it.
and

Quote:

Cineframe30 and Cineframe25 field-double, resulting in a 30 fps or 25 fps image update rate with halved vertical resolution (halved in HD, but only marginally impaired in SD).


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