Thanks John,

I'm actually working with the Waveform Monitor, too.  I see that has two settings:

1.  Dotted Lines 0 at bottom and 255 at top.

2.  Hard Lines 0 - 100 between the dotted lines.

My understanding is that black level 16 is the Hard Line 0 and white level 235 is the hard line 100.

So I'm trying to keep my signal between the 0 - 100, only allowing transients to go below or above.

Interestingly, though, if I import footage into VPX6, while the preset is set to BT 709, blacks can go right down to dotted line 0 and up to dotted line 255.

Also, Auto Exposure and Auto Color distribute the signal right down to 0 and up to 255.

So I'm not sure how the preset works at setting maximum levels at 16 - 235.  Maybe I'm misunderstanding the levels as laid out in the Waveform Monitor?

Appreciate more input on this, thanks.

Seamus

Hi

Post removed - see above correction

John

Hi John,

I seem to be misunderstanding the measuring instruments.  I didn't realise the Histogram BT 709 was a video effect as such, but just a measuring device.  Thanks for your patience.  Do you know if there is any kind of step by step tutorial for using the instruments?  I'm accustomed to Media Composer where you actually set the 16-235 levels manually in the measuring instruments section.

Seamus

Hi

. . . . I seem to be misunderstanding the measuring instruments. . . . .

Apologies you are not the only one    my previous post was in error in assuming the Histogram BT 709 was an actual adjustment when in fact it is setting the limits of the instruments such that they indicate when the limits of the specification are exceeded.

There are tutorials - mainly for Premiere - but the principles are the same - about using some of these instruments on Youtube.

John

Hi

. . . . I find it's easy to bring the white down to the 100 line, but very difficult to bring the black up to the 0. . . . .

At last I am beginning to get my head round this!

Are you using the Brightness adjustment to bring the white level down - if so then the Contrast is used to adjust the Black level up / down.

John

Hi John

That sounds back to front. Normally the brightness controls the black level and Contrast the white level.

Selective Brightness (in MEP) is the Gamma adjustment.

Peter

There seem to be some problems within VPX6 and its Measuring Instruments that are hard to define.  As though it is reading / displaying the 0-255 and 16-235 colour space flags incorrectly.

1.  It imports DSLR footage incorrectly - the blacks are crushed.  'Dark' footage has to be transcoded to another format before import.

2.  After import of any footage, the blackest signal is placed at the 0 line on the 0 - 255 scale (Waveform Monitor and Histogram).  In Media Composer, another NLE I use, it's placed at the 16 line of its 0 - 255 scale.

3.  In MPEG Streamclip I transcoded DSLR footage (with plenty of blacks) to DNxHD at 0-255 AND 16-235.  When imported to VPX6, both clips are place at the upper 0 line (IRE 0, I believe, the one above the bottom 0 in the Waveform Monitor), and the blacks have become a washed-out gray!  In Media Composer, both clips are placed at the 16 line and look great.

4.  Media Composer handles 'Broadcast Colour Space' logically and correctly.  It's Waveform scale, from bottom up, is 0, 16, 235, 255.  16 - 235 is for Broadcast.  In VPX6, the Waveform scale is 0, 0, 100, 255.  I suppose the middle 0 - 100 is Broadcast limits, but it seems impossible to get black at the Broadcast limit of 0.  It's a gray!

In VPX6 the Brightness and Contrast sliders seem inter-dependent.  I've found increasing the Brightness level lifts the blacks up from the bottom immediately (controls black level).  Decreasing it, brings the whites down.  The Contrast adjusts the blacks at the bottom end.

FINALLY, I love VPX6's 64-bit speed.  For now, I'm going to completely ignore what the measuring instruments say.  Just colour correct and get a good picture on a calibrated monitor.  I've exported HD files and burned Blu-rays and they all look great on various screens.

I still don't really know where or what the Broadcast levels are in VPX6, and my material is not for broadcast at this point, so, until this issue is resolved, I'll just keep editing.

Any further insights welcome!

Seamus

Hi

. . . . That sounds back to front. Normally the brightness controls the black level and Contrast the white level. . . . .

That sounds back to front to me   - brightness by definition is 'the intensity of the energy output of a visible light source'  and contrast the ratio between the darkest and lightest points

That is:

    - as you increase the brightness, the source emits more light and if taken to the maximum on a monitor gives white.

    - as you increase Contrast the bigger the difference between the black and white and vice versa.

@ Discburn - . . . . Just colour correct and get a good picture on a calibrated monitor. . . .

I agree totally with this method especially after burning BD with the video set to comply with BT 709 and doing it by eye.  The BT709 disc lacked contrast and punch on bright colours and generally look as if some shots, taken on bright days, were actually taken on dull overcast days.

John

I've emailed a list of 'bugs' to Magix support.  I received a reply stating that the Measuring Instruments, as they are only new, are not yet connecting well with other elements of the software.

This 64-bit version is really fantastic.  Just needs a good polishing!

I hope a patch / update comes out soon!

Seamus

Hi John

Fair enough but I think you know what I mean.  The problem with using the brightness to adjust the white is that it requires so much movement of the control to change the white noticeably that the black is thrown way off and of course the two (Br and Con) are inter related. Some useful stuff here: http://spareroommedia.com/video/monitor_setup.html

Seamus

Try loading one of the SMPTE Colour bar charts that are in the Test Images folder in Magix onto the timeline and see where the PLUGE strips (bottom second from the right) and the 100/100  bars, fall on the Scope. Only have MEP here but if I apply the Auto Exposure setting it does not change the exposure, black or white, sort of confirming what you said that they put it at maximum black and 255 white. 

Peter 

Peter,

That's exactly right.  SMPTE Bars come in at 0 - 255.

The same bars imported to Media Composer come in at 16 - 235.

Seamus

Hi Seamus

And I read somewhere that Premiere and After Effects read differently also...!

Peter