XL2 footage = flat Histogram at DVinfo.net

Kevin Janisch · March 29th, 2005, 01:21 PM

I've been playing around with some footage in Premiere Pro 1.51 and noticed that the Histogram in levels is pretty close to being flat across the board. There is a slight spike for the midtones. I imported a clip that looks similiar to the eye taken with my XL1s and the histogram looks typical. I exported a frame and looked at the histogram in Photoshop and it looked fine there, although not as mountainous as the XL1s, which is expected.

All settings with the XL2 are default and I know the colors and tones are more muted and natural with these settings but the histogram does not look right.

I even imported footage from samples here, such as the infamous "Zoo Footage" and "Cloudy Day" and they're flat as well.

Anybody experience this?

Barry Goyette · March 29th, 2005, 03:34 PM

Kevin

I just imported a frame, and the histogram looks fine to me, although I'm not sure what you are surmising from the presence of flat histograms. A histogram is a graphic interpretation of the quantity of individual levels in an image. Thus it is highly dependent on the subject matter for it's "shape". And its shape would not be immediately indicative of any malfunction or defect in the camera, short of some other visual cue like, "my picture looks like a kodak grayscale stepwedge", which, in theory, would produce an absolutely flat (but slightly spikey!) histogram.

If, however there was a histogram from a native DV frame that included a number of gaps or spaces in the histogram...then you'd have something...The frame I chose was a test frame I posted months ago, in comparisons with the DVX100. The histograms of the two are remarkably similar in shape, although the DVX file shows a significantly more jagged-terraced look, which would indicate a greater amount of processing/degradation (makes sense as the original dvx was 8-bit, whereas the xl2 is 12-bit).

Barry

Kevin Janisch · March 29th, 2005, 05:32 PM

Barry,

Thank you for your reply. My concern is with adjusting the levels for color correction. It is rather difficult to see where to adjust input and output levels graphically via the histogram when all I see is a few spikes for the mids and nothing but a flatline for everything else.

I was just curious if anybody else ran into this problem with Premiere Pro.

Just now, I checked out the levels of the same clip with After Effects Pro and the histogram is fine. So I'm not sure what's going on with Premiere but with 6.5 of AE having preview output via firewire it is a no brainer which app to color correct in.

Kevin

March 29th, 2005, 01:21 PM	#1
Kevin Janisch Major Player Join Date: Jan 2004 Location: Monterey, CA Posts: 406	XL2 footage = flat Histogram I've been playing around with some footage in Premiere Pro 1.51 and noticed that the Histogram in levels is pretty close to being flat across the board. There is a slight spike for the midtones. I imported a clip that looks similiar to the eye taken with my XL1s and the histogram looks typical. I exported a frame and looked at the histogram in Photoshop and it looked fine there, although not as mountainous as the XL1s, which is expected. All settings with the XL2 are default and I know the colors and tones are more muted and natural with these settings but the histogram does not look right. I even imported footage from samples here, such as the infamous "Zoo Footage" and "Cloudy Day" and they're flat as well. Anybody experience this?

March 29th, 2005, 03:34 PM	#2
Barry Goyette Trustee Join Date: Oct 2001 Location: San Luis Obispo CA Posts: 1,195	Kevin I just imported a frame, and the histogram looks fine to me, although I'm not sure what you are surmising from the presence of flat histograms. A histogram is a graphic interpretation of the quantity of individual levels in an image. Thus it is highly dependent on the subject matter for it's "shape". And its shape would not be immediately indicative of any malfunction or defect in the camera, short of some other visual cue like, "my picture looks like a kodak grayscale stepwedge", which, in theory, would produce an absolutely flat (but slightly spikey!) histogram. If, however there was a histogram from a native DV frame that included a number of gaps or spaces in the histogram...then you'd have something...The frame I chose was a test frame I posted months ago, in comparisons with the DVX100. The histograms of the two are remarkably similar in shape, although the DVX file shows a significantly more jagged-terraced look, which would indicate a greater amount of processing/degradation (makes sense as the original dvx was 8-bit, whereas the xl2 is 12-bit). Barry

March 29th, 2005, 05:32 PM	#3
Kevin Janisch Major Player Join Date: Jan 2004 Location: Monterey, CA Posts: 406	Barry, Thank you for your reply. My concern is with adjusting the levels for color correction. It is rather difficult to see where to adjust input and output levels graphically via the histogram when all I see is a few spikes for the mids and nothing but a flatline for everything else. I was just curious if anybody else ran into this problem with Premiere Pro. Just now, I checked out the levels of the same clip with After Effects Pro and the histogram is fine. So I'm not sure what's going on with Premiere but with 6.5 of AE having preview output via firewire it is a no brainer which app to color correct in. Kevin