DVCPRO HD - DPX Output 1280 X 1080 instead of 1920 X 1080.

I am outputing DPX files from FCP for color correction in DaVinci. FCP is outputing 1280 X 1080 instead of 1920 X 1080. I understand FCP and Quicktime know that DVCPRO HD is supposed to be 1920 and upconverts. I would like to have our colorist correct and then master to HDCAM at the same time.

Is there any way I can create DPX files that are 1920 X 1080 so I don't have to come back into FCP and output to Panasonic AJ-HD1200A DVC PRO HD Deck later?

Thanks,
Angelo

You could create a 1920x1080, square pixel sequence preset. Then drop your DVCPRO HD timeline into this. The DVCPRO HD has a 1440x1080 pixel aspect ratio, but when that sequence is dropped in the square pixel 1920x1080 sequence, it will come out correctly at 1920x1080.

The only thing I don't know is what compressor to choose for the 1920x1080 sequence and if this is even used if you export straight away without rendering. Obviously you don't want to add any more compression cycles if you can avoid it.

Are you using the GlueTools componets for the export to DPX?

--Mark

I tried and although the image is 1920 X 1080 the image gets squished. Don't think the DDR ahead of the DaVinci can conform back to normal.

Did you create the 1920x1080 sequence with a square pixel aspect ratio. I tried this with 1440x1080 DVCPRO HD media by nesting the standard DVCPRO HD sequence into the 1920x1080 sequence and it worked fine for me. Also what DPX export component are you using?

I am using the Gluetools component.

Yes, I did create 1920x1080 sequence with a square pixel ratio. Tried many different compressors. The sequence settings for this made the image compress to a square box. So I tried anamorphic 16x9. That didn't help.

I don't understand what you mean by "nesting?"

Got it! Was able to nest the 1280 in a 1920 sequence. Output looks good. After rendering sequence doesn't play well A little choppy. But I don't need to play from that sequence. This is for 1920x1080 DPX output only.

Testing trailer assets Monday at Notch in Toronto. Will update this post after the test.

Thanks Mark.

With regard to rendering what codec do you have selected for the 1920x1080 sequence? Ideally you don't want to render the program in the 1920x1080 sequence as this will be another compression, just do the DPX export right after nesting.

Having said that, I'm not sure how FCP works in this respect - it might be going through the sequence codec to the DPX format on export anyway, in which case it makes very little difference.

Best thing is probably to choose a very low/no compression codec for the 1920 sequence. BitJazz would be a good example.

--Mark

Yes, I did the export right after nesting. Not rendered.

I selected the TIFF codec. I went through a number of compressions from uncompressed to slightly compressed. TIFF and Uncompressed compressors both produced a 7.9 meg file. My thinking is that DPX is similar to a TIFF in regard to a single frame uncompressed photo.

-Angelo

Hi Angelo,
Cool, sounds like you have got the best output possible. Good luck with the grade.
Regards
Mark

Hmm,

In a future version, I might be able to plug in the pixel Aspect ratio, into the DPX header. However, this might open a nasty can o'worms. I can't be certain that all Apps that read DPX images even pay attention to the aspect ratio fields in the file.

(From what I've seen, they don't.)

Its probably a worthwhile experiment, though.

bob.

Robert Monaghan
Glue Tools - Cineon & DPX QuickTime Components
www.gluetools.com
Santa Barbara, CA