HMC 150 and 30P
 

Does the HMC 150 record 1080 in 30P mode?

I see it says over 60i, and I am not sure what that means.

Can someone explain what this means "1080/30p (over 60i)"

I am considering this camera, but need it to shoot 1080 30P and mix on a timeline with my EX1 and HV30

Not sure what it means either but I have the HMC-150 and shoot in 30p (1080) and it works great.

Simon

Each frame is captured as a progressive image but then split into fields before it is recorded to the card as a 60i stream. When the footage is de-interlaced by your TV or in your NLE it plays back exactly the same as if it was recorded 30p.

Progressive footage should never be de-interlaced. De-interlacing progressive footage really just means that you're throwing away half your resolution.

NLEs will recognize the "progressive" flag and will be able to use the footage exactly as if it had been recorded in a progressive data stream in the first place. In other words, if it's shot 30p "over 60i", then the NLE will know exactly what to do with it and will treat it as 30p, as you intended.

Barry, can you please explain how de-interlacing throws away half your resolution? I was under the impression that when you de-interlace, then both the fields are displayed at the same time. Temporal resolution would be decreased but spatial resolution would be higher, wouldn't it? Or does de-interlacing simply mean the NLE only plays the 'a' fields and ignores all the 'b' fields?

Pretty much yes -- it ignores one field and duplicates the other to fill in the gaps.

Or, if you're using an advanced de-interlacing technique such as blended fields, it'll try to synthesize a new field by blending the "A" and "B" fields together.

In any case, you DON'T want that to happen to your progressive footage. Progressive footage has full information detail in each field and that should be preserved as-is.

I don't think that "1080/30p (over 60i)" has the full information in each field.

Each field more likely has half the information, so that you need to combine the two fields to restore full resolution, at 30 frames per second.

But that's speculation - I'm open to be corrected.

You are correct, that's exactly how it works, and that's exactly why you wouldn't want to "de-interlace". De-interlacing would destroy the valid information in one or the other field.

Basically the footage will play back properly on a 60i timeline, just make sure you don't apply any deinterlacing processing to the clip. (i.e. deinterlace method: interpolate, blend, none. choose "none")

Yes, but there's another complication which is that if you use rendered graphics or titles on a 60i timeline, but you were using 30p footage, the graphics will be split across the fields.

Whereas if you use a 30p timeline, the graphics will be rendered as 30p, frame for frame.

So if you're using 30p footage, it's usually best to use a 30p timeline to edit it.