Why is does it look different thru AMA then thru IMPORT?

[Pepijn Klijs]

Yesterday I learned that the best way to get quicktime footage generated by FCP (like pro res or h264) into Avid is by using AMA link and then transcode, instead of directly importing it. Although colorspace and gamma issues seemed to have disappeared using this method, I did encounter something else…

Strangely, using AMA link to file alters somehow the dimensions of the frame. It was like something shifted a few lines. Sorry for my bad explanation.

Just now I did a test on a media composer 6 by importing and AMA linking + transcoding a smpte pattern. I got the same strange shifts.

Here’s 2 jpeg stills from it, make sure you check the top of the images where the ama version shows a thin black line.

The AMA version:

The imported version:

Does anyone know what causes this difference I can clearly see?

Avid/FCP Editor, Amsterdam, The Netherlands
http://www.pepijnklijs.nl

[John Pale]

What is the frame size of the image and is it progressive or interlaced?

[Pepijn Klijs]

Its the smpte test pattern image, found in avid supporting files. Project format was PAL 25i

Avid/FCP Editor, Amsterdam, The Netherlands
http://www.pepijnklijs.nl

[John Pale]

When you used the straight import, what were all your settings?

Did you assign a field order or did you set it to leave it as is (progressive).

[Pepijn Klijs]

I choose, order for current format.

Will test now with other settings..

Avid/FCP Editor, Amsterdam, The Netherlands
http://www.pepijnklijs.nl

[Pepijn Klijs]

In my quest for wisdom I also checked teh Avid help files on the topic of field order/import and got even more confused.

it says:

• Odd (Upper Field First) ordered: Select this option if the file is odd ordered and you are importing it into an even ordered format, for example, when you are importing PAL DV into PAL.

First, I always thought that DV PAL was lower field first and IMX MPEG50 for instance is upper field first. I’m almost sure about this…

What’s your take on this?

Avid/FCP Editor, Amsterdam, The Netherlands
http://www.pepijnklijs.nl

[John Pale]

Dont set a field order. Select ordered for current format. The image file is progressive.

You really shouldn’t be using AMA for graphic files. Just import those. Use AMA for video files.

[Pepijn Klijs]

sounds like the correct thing to do, I agree. And I would like to add that you should also be carefull mixing these methods for the same footage. Reason why is because today I had to crop a piece of video that was above the identical clip, but because I used I different method of importing, the images didn’t match well anymore. Actually I now realise (its been a long day) that the original footage was captured from a XDCAM deck, and the cropped overlay clip was imported using the ama + transcode method.

Thanks for your suggestions!

Avid/FCP Editor, Amsterdam, The Netherlands
http://www.pepijnklijs.nl