Simply export with square pixels and do not let yourself get confused by the SAR, screen aspect ratio.
(1920 x 1080) x 2 = 3840 x 2160.
Thank you for your answer but the PAL format is not square pixel. I want the video to play in 16/9 but with standard PAL resolution of 720x576. The 2 choices of pixels ration proposed by the MPEG encoder are not 16/9. Why ?
1920x1080 has square pixels aspect ratio of 1.0
SD PAL has non-square pixels with a PAR of 1.46 for widescreen.
If its going to dvd choose a PAL widescreen preset from the mpeg2-dvd format.
Don't forget to set the crop Scale to Fill otherwise you will end up with narrow black vertical bars.
If you just want mpeg2 select the pal dv preset and set it to widescreen and change the field order.
OK, now you are talking. Those details were missing from your OP.
Export to MPEG2-DVD PAL Widescreen High Quality, turn on Maximum Render Quality and in the Output tab select Scale To Fill.
Ann made a very useful remark that I left out. Just to make sure you don't get into problems, make sure that you do not run into field reversal problems. How? Well, HD material is UFF, normally SD DVD is LFF, but when you encode from HD material to DVD, you do not want field reversal, so keep everything UFF.
Thank you Harm,
I always leave the video in progressive mode. I found the output scale tab, that is what i missed. Usually, i don't check the maximum render quality (much longer render time) but this time I will do it.