Gray Bar Bug

[Jay A. Kelley]

As I understand it, Jarred said the gray step ladder on the right side of the screen was to insure proper contrast/brightness for the MONITOR (I.E. EVF or LCD)

It has NOTHING to do with recording, or the image.

If this is indeed the case it would seem the step ladder is working on the LCD but not the EVF. Changing iris, and/or shutter, etc does NOT change the step ladder on the LCD but drastically changes it on the EVF.

So something's not quite right here.

Jay

 

[Stuart English]

Exposure strip

Exposure strip

The Grey Scale chip is rendered into the GUI and is therefore not affected by any changes in IRIS, ISO etc etc. Its provided so that you don't fool yourself into making poor exposure judgements based on the brightness of the image.

What do I mean by that? Well the brightness and contrast of the image are a relative thing, its affected by the monitor brightness and the ambient lighting and the angle of view to the display. All of those can throw your judgement off. So this grey scale strip gives you a known reference.

The RED-EVF has an auto-contrast feature. That's why you can see the last 2 or 3 bars of this grey scale crushing to the same white value sometimes. This circuit helps the EVF see into the dark areas of the image with greater clarity.

The RED-LCD does not do that as absolute blacks are impossible to generate on a sunlight readable flat panel display.

That's the cause of this difference in behavior.....

 

[Jay A. Kelley]

So you are saying that if I change the iris on my lens, it will change the gray strip in the EVF but not the LCD?

Because that is what it's doing.

Jay

 

[sander kamp]

That would explain what I am seeing in my EVF and what I thought was a defect.

So is that a hardware feature/limitation for the EVF or is it something that can be turned off in software in some moment in time? I am not sure if I find it that useful.

 

[Stuart English]

EVF Auto-Contrast

EVF Auto-Contrast

So you are saying that if I change the iris on my lens, it will change the gray strip in the EVF but not the LCD?

Yes. That's the auto-contrast function working. If you increase DARK DETAIL above 2% the effect is more marked.

 

[SF Geek]

Is there a way to lessen this effect? I think that's why I'm loosing highlight detail in the EVF that I can see in the LCD.

 

[Stuart English]

EVF Auto-Contrast

EVF Auto-Contrast

Is there a way to lessen this effect? I think that's why I'm loosing highlight detail in the EVF that I can see in the LCD.

You are not loosing any highlight detail if its set up correctly. In Build 16, the default value for Dark Detail is ON and 1%.

That means when 1% of the pixels in the image are above a certain luminance threshold, we use the full range of input values - hence if you open up the iris you will see all the bars in the grey scale strip.

Now close down the iris so the scene is darker. When less than 1% of the pixels in the scene are at that threshold value, the EVF remaps the remaining values below that threshold, giving you better visibility in the dark areas of the image.

Now compare this to Dark Detail OFF.

 

[SF Geek]

I'm not on build 16 yet. I'll see what's up when I get there.

 

[wedowee]

Are detailed instructions for using the grey scale chip going to be added to the manual? I don't have my EVF yet, and the grey scale chip does not appear to function on my LCD. Thanks.