Histogram Help-Please

[Lou Bruno]

The manual is very sketchy as it relates to the use of the histogram in the Z-7/HVR-270. There are two types.

Could someone please advise on the proper use of both the NORMAL and ADVANCE settings?

Thank you.

[Luc De Wandel]

I'll try to explain in my own words (and my poor English): a histogram is a graphic presentation of the density values in an image. On one side of the graph are the darkest shadows, on the other side the most brilliant highlights. Correct exposure is when the graph fills the whole horizontal ruler. Of course, when the image is very contrasty, shadows and highlights are closer together on the graph than normal. Then correct exposure is when the whole graph is in the middle of the horizontal line.

For a more scientific approach, yuou might take a look here: http://www.luminous-landscape.com/tu...stograms.shtml

[Lou Bruno]

Thanks. I am trying to understand the ADVANCED setting in the Z-7/HVR-27. There is a RED line and a yellow line in the graph. The yellow line disappears when ZEBRA stripes are set to OFF.

[Luc De Wandel]

Apparently, everything at the right side of the yellow line is the 'overexposed' area. The zebra pattern is visible in those areas. I have no idea what the red line indicates, however.

[Peter Greis]

Originally Posted by Lou Bruno

The manual is very sketchy as it relates to the use of the histogram in the Z-7/HVR-270. There are two types.

Could someone please advise on the proper use of both the NORMAL and ADVANCE settings?

Thank you.

The NORMAL setting will show a line (it's yellow if my memory serves me) where you have set the zebra. If zebra is off then you won't see the line. So if you set the zebra at 90% everything on the histogram (pixels that fall above 90% IRE) will be to the right of the line.

the ADVANCED setting adds the red line which indicates an average of all the pixels in the frame by brightness. I adjust my iris to try and put the red line somewhere in the middle.

[Lou Bruno]

Thanks to all!