140 replies to this topic

[hmcindie]

I think you guys are quite confused with 50i. Yes, you can drop that into a 25p sequence and edit away but the NLE will just deinterlace the material quietly in the background. You can also drop a 50p sequence into a 25p timeline and the NLE will just drop half the frames.

 

I can guarantee you that the RX100 does shoot in fact 50i.

 

"Opening it in Quicktime or Photoshop will show you the interlaced lines." If you have interlacing lines then you are dealing with interlacing. Interlacing means that you have 50 frames interlaced into one 25p file. That's how it worked in the "old" days. Those frames are then extracted by either bob-deinterlacing (preserving the 50 frames per second) or just by dropping half the frames - and resolution - away and staying at 25p.

[hmcindie]

Yes, numerous consumer range cameras from various manufacturers seem to do this, use an interlaced flagged container but store progressive frames, Canon did it with the HV series HDV mpeg2 camcorders causing confusion. I think it was another one of those artificially seperating the codec between consumer and professional ranges or some avoidance of the cost for licensing maybe.

 

Canon HV20 had a SPECIFIC mode for progressive 25p footage. That was actually completely progressive and great looking to boot. It was inside a 25i file (because that's what HDV was at that time) but there were no interlacing lines and there was no need to deinterlace anything. NLE's at that time didn't do deinterlacing automatically (except FCP which occasionally caused quite big problems as it wanted to deinterlace stuff that didn't need it. Still some people fall for those pitfalls and then you see "testvideos" which have 50% less resolution)

 

It also shot 50i the exact same way an RX100 does it.

 

You would not see any interlacing lines with the HV20 in progressive mode. If you see those lines in quicktime (or a player that does not do deinterlacing, WMP actually does do it) then it means that a) it is interlaced and  it has 50 frames interlaced in it.

[yellow]

I still have my HV30 and I'm aware of the shooting modes, thanks. The RX100 clip wrapped source from earlier up this thread, that I opened in Avisynth, which does nothing unless told to was NOT interlaced as far as I can see.

 

What do you see here, decompressed with ffmpegsource2, histogram(mode="classic"), ConvertToRGB(matrix="PC.709)?

 

http://dl.dropbox.co...rx100_pc709.png

 

Sure the RX100 may have an interlaced mode, but the source I'm talking about was not it would appear. Two 25P progressive streams as discussed earlier.

[Bruno]

I still have my HV30 and I'm aware of the shooting modes, thanks. The RX100 clip wrapped source from earlier up this thread, that I opened in Avisynth, which does nothing unless told to was NOT interlaced as far as I can see.

 

Keep in mind that clip was shot as 50p.

 

Shooting 50i does seem to look interlaced in most apps. Have a look at the new .mts clips.

The question here is, I don't think it's real interlaced footage, the camera is probably interlacing it AFTER capturing a clean 25p frame.

 

 

 

I can guarantee you that the RX100 does shoot in fact 50i.

 

The difference is that de-interlacing true interlaced footage will never give you 100% clean results, you'll always get some interlace artifacts, which does not seem to be the case here, which leads me to think it's a fake interlacing, that you can easily undo to get a clean 25p image.

[yellow]

Keep in mind that clip was shot as 50p.

 

Shooting 50i does seem to look interlaced in most apps. Have a look at the new .mts clips.

The question here is, I don't think it's real interlaced footage, the camera is probably interlacing it AFTER capturing a clean 25p frame.

 

Argh! My apologies, the clip wrap mov is 50p as you say.

 

Looking at the 50i MTS files yes they're really interlaced not progressive, it's only the motion that manifests the lines by nature of the interlacing process.

 

@hmcindie, my apologies, crossed wire's, not reading the thread properly.

[Bruno]

I have had a play with numerous profiles on the RX100 since my purchase last year. To be honest I have not seen much difference using a flat profile compared to a standard profile when it comes to grading.

Ir you look at the Portrait Style (standard vs flat) test image you'll see that even within the same profile, using flatter settings will give you a cleaner image after grading, compared to leaving everything at 0.
Of course we're talking about subtle details, but everything helps when you only have an 8 bit image.
Sending a flatter image to the encoder will allow it to do a better job, leaving you with less compression artifacts, banding, etc. One extreme example of this is the B&W test, just not having to deal with color makes the same bit rate footage look A LOT less compressed.

[yellow]

I have had a play with numerous profiles on the RX100 since my purchase last year. To be honest I have not seen much difference using a flat profile compared to a standard profile when it comes to grading. The camera is great but even at 1.8 is not great in low light with the small sensor and grading then becomes near impossible.

 

Here is a couple of examples shot with the standard picture profile with everything set at 0 except for contrast which is at -1

 

Thanks for posting the low light files, but really need native source files rather than encodes out of the NLE.

 

Bruno, do you have a low light MTS you could make available?

[Bruno]

Looking at the 50i MTS files yes they're really interlaced not progressive...

Do you agree though that the images seem to be captured progressively and only interlaced when recording the file?
Do you see any interlace weirdness at all after de-interlacing?

[Bruno]

Bruno, do you have a low light MTS you could make available?

I'll post something later on tonight that will allow you to evaluate color clipping, just hasn't had a chance to do it yet.

[yellow]

Interlacing is done at encode time so yes. Depends on the deinterlacing method as to the quality, haven't tried as yet.

[jgharding]

Portrait is definitely the flattest, it has a better highlight roll-off than Sunset, by a bit of a stop.

 

If you use portrait all -3 and DRO at 3, then grade in a 32-bit RGB app like After Effects, that's as close as I've found to Cinestyle on this camera.

 

It's very good. Only the motion codec artifacts hold it back.

[Bruno]

Bruno, do you have a low light MTS you could make available?

 

Here, see if this one helps:

https://dl.dropbox.c...w/testClip2.MTS

[mojo43]

Great post Bruno, thanks for all of the info! It's great that you can get 25p out  the 50i footage. I wish there was a way to somehow get 24p out of this camera. I guess dropping frames is the only option. Sigh...

[richg101]

I just found a rather nice feature on the nex5n (which will be the same on the rx100 and other nex's)

 

You know how annoying it is when the image aspect ratio and brightness changes after you press record?  Well, set your camera to 16:9 mode on stills and you'll get more screen area to compose in before you press record, and the screen wont crop and change your view after pressing record.  Also for some reason you get a lot more accurate brightness/colour representation of how the image will look during recording, before you actually hit record:)

[Bruno]

Yes, I've been using the 16x9 option for video recording, and I think that if you're in video manual mode you don't get that brightness change when you hit record, isn't that the case on the Nex?

[richg101]

Yes, I've been using the 16x9 option for video recording, and I think that if you're in video manual mode you don't get that brightness change when you hit record, isn't that the case on the Nex?

 

up until i changed to 16:9 mode I found whatever setting I was using, flat profile, black and white, dro on/off, 50p/25p etc,  when i pressed record the image changed very significantly from how it looked before pressing record.  Now there seems to be less of a jump

[jgharding]

Yes Video Manual gets rid of most of the reframing issue.

 

The reframing is to do with digital stabilisation i think.

 

The colour change can be a bitch too, but again, it's not there in video mode.

[Bruno]

up until i changed to 16:9 mode I found whatever setting I was using, flat profile, black and white, dro on/off, 50p/25p etc,  when i pressed record the image changed very significantly from how it looked before pressing record.  Now there seems to be less of a jump

 

Yeah, it's not about the settings, it's the shooting mode in the upper wheel, Manual Video will solve it.

[Bruno]

Just a heads up, I've updated the Record Settings section and added the Shooting Mode and Dynamic Range Optimizer sections to the original post.

[mojo43]

Awesome, thanks Bruno!