Dynamic Range without Washed Out Midrange

basspig

basspig

Veteran
Spent an afternoon with my wife and inlaws at the park today, and used the opportunity to test various picture profile recipes.

Before I begin, I should note that I have been using STD4 for almost everything to date. It seems to keep a good deal of punch in the midtones with a decent dynamic range.

Today I trained the camera on the landscape and clouds together and rolled through the various gamma choices. Many were too dark looking for my taste, but I stopped on STD3 because it looked like it had punch in the right areas while controlling highlights. With this as a starting point, I then dialed in positive gamma values. 99 was too much, but 50 looked about right on the LCD. I played with black gamma next, finding about 10-15 was about right. Black level set to -2.

Then I proceeded to shoot various scenes. Much of the time, I found the histogram was only about 2/3 populated. So I went manual on the iris and opened it up from f5.6 to f4. This brought the overall brightness up, without losing cloud highlight detail. I locked in this iris setting and shot the rest of the scenes like this with the exception of 5b.

The most notable thing is that I was able to expose for the clouds without crushing the shaded areas. This is different than going overboard on black stretch/gamma, because the mid tones don't wash out with this STD3 gamma curve.

Let's look at the images:

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Here's an extreme backlight situation--the sun is peering through silver-lined clouds, almost directly into the lens and the subjects are in the shade.

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Here is what the scene looks like from the other side. Note my daughter in foreground shade is adequately exposed while the bright cloud tops in background have full detail.

Here is the group shot with exposure set for their faces. Note clouds are not 100% whited out:
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Here is a favorite example of what I call "live beyond 100 IRE". The following image is the original image, truncated by Premiere CS3:
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This next image is the same frame, but with the dynamic range scaled 0-235 using levels in the Fast Color Corrector:
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As you can see, there is real significant detail above 100 IRE.

Here is a scene that has always given my SLR cameras a challenge, because exposing for the flower petals usually results in a crushed black for everything behind it. Here, the areas in shade under the flower are clearly visible:
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Here is a nice wide dynamic range shot, where clouds are properly exposed, yet shade under the trees is not crushed to black:
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All of these were shot with STD3 and a boost to the gamma curve to liven up the mid tones without washing out color saturation or making mid tones look milky.

Indeed, there IS life beyond 100 IRE!
 
Pardon my sketchy details.. I was using STD3, Gamma set to +50, Black Gamma +10, Black Level -2. HiSat matrix. Knee set to auto on most of the shots.

Apparently the curve in STD3 is just right for boosting the gamma without washing things out and flattening the midtone til they look chaulky. Nice thing about this is there's no visible grain/noise in the images, shooting at -3dB!
 
wow Black Gamma set to +10 and no visible noise detected for daylight exterior. that's interestingly contradictory to what i've been reading about Black Gamma and Noise reduction. i'll have to try it out for my own eyes.
 
Noise on the EX1 is a peculiar thing. It's not really in the blacks--every time I've seen it, it's in the grey range and showed up mostly on sky shots with heavy clouds. I think the combination of increasing the exposure (aperture) and using -3dB gain worked to banish the noise, but also this particular curve with the gamma at +50 may have routed most of the picture energy around the noisy range. Another factor may be temperature. The videos where I could see some noise in the clouds were all-day shoots on the tarmac at military facilities or airports, in the hot sun where the camera was almost too hot to handle. We know that CMOS noise is a function of temperature, so keeping the camera cool could be a valuable factor in achieving clean video.

I noticed the lack of noise on my Memorial Day footage. A black Packard automobile passed by, and a frame by frame analysis revealed a clean near-black rendering of the car's finish. The blue parts of the sky were free of grain as well. It's the smoothest looking video I've shot.

Today's footage was surprising in that I was able to:

1. achieve that much dynamic range and
2. do it without making the picture so noisy as to be unusable.

The EX1 has a lot of untapped ability. I've just discovered another combination of settings that works well for landscape work.
 
have tested the cine3? is slightly better at spinning the exterior, the color scales are fine my opinion :-) This week I tested both with difficult situations and I decided to cine3 in esters and STD4 inside
 
Only briefly. My impression was that the pictures were too dark, and highlight clipping didn't SEEM to benefit. I'm not sure if the LCD displays all the way to 109 IRE or not.
Regarding color, I did note that the blue sky was rendered more turquoise. Perhaps that's my the cine matrix shifts blues toward purple--used together, they probably normalize the blue range.

Definately more testing to be done here, but I am significantly impressed with the STD3 results.
 
I too have settled upon STD3 for my Ex-1.

This gives the best mix of highlights without losing the shadows.

Being able to radically alter the image in-camera is one of the best attributes of this camera.
 
Yes, and having an option to limit hilights to 100 IRE may be priceless, as I'm finding there is no easy way to scale 109 -> 100 IRE *and* render it to Adobe's Media Encoder without clipping hilights. I'm the the process of re-rendering some footage.. first I had to render it out to uncompressed movie (thankfully I have a 2 terabyte RAID array and a 1 terabyte RAID array on the same workstation) as that was the only way to get rendered what I saw on the screen after processing to recover the highlights, and now I've imported that render and am making a new h.264 file for Blu-ray.

In the future, I may just say to heck with this and set my camera to Cine 2 gamma and leave it at that so I never have to deal with Adobe's crummy handling of superwhite levels.


Michael, no relation to the other member. And with the ambiguity of English, he could be a fisherman --or a subwoofer maniac like me.. can't tell by reading alone.
 
I was working on some aviation footage last night, and found this shot, where the iris response time lagged the quick panning from a dark underbelly to the sky and in that moment, a few frames looked overexposed... but...

Here is the original image, as interpreted by Adobe Premiere with it's arbitrary clipping at 100 IRE.
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Here is that same frame, with RGB Curves applied so as to bring all portions of the image to within 100 IRE. There is substantial detail in the clouds that is whited out in the uncompensated image. Almost an f-stop of additional detail found above Premiere's normal working limit!
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