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23 stops of range?

Michael.B

Michael.B

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I saw this at the recent HPA retreat. Thomson was showing an image from the GV Infinity claiming to have 23 stops of range. Apparently the light in the images, a 500 watt halogen, is the sole light source (maybe some reflectors in the room). Found the images on cinematography.com and thought people might be interested in hearing about it here.

15111_1235799734.jpg

15111_1235799765.jpg
 
hard shadow

hard shadow

Michael.B said:
I saw this at the recent HPA retreat. Thomson was showing an image from the GV Infinity claiming to have 23 stops of range. Apparently the light in the images, a 500 watt halogen, is the sole light source (maybe some reflectors in the room). Found the images on cinematography.com and thought people might be interested in hearing about it here.

15111_1235799734.jpg

15111_1235799765.jpg
Click to expand...

Do you see the hard shadows by the botles?
regards Robert
 
i dont buy that that's the only source.
 
typo.. it's probably 13 instead.. :)
 
If it's true it's interesting, but this picture proves nothing.
There is clearly a lightsource lighting the scene. Just make it a big one and you will be able to see the filament with any camera.

Joost
 
Definitely light coming in from somewhere else and I don't believe, with that shadow, that it's reflected from that 500W halogen. I''ll believe 13 stops, not 23 stops. It's going to take a lot more than a shitty still of cereal boxes, wine bottles and a cheap work light to convince me of 23 stops.
 
Well right off the bat:

The hard shadows are not from a bounced light source. The shadows would be softer. Further more, you will notice a tight specular highlight reflected in the bottles on the left as well as the two on the right just above the halogen. This makes it clear that there is at least one source pointed at the scene. The bottles on the right have multiple highlights which could either be refraction or revealing more sources. Either way I can confirm one source pointed at the scene. The harshness of the shadows and the shape and style of the highlights tell us that it is a directional lamp with a lens.

Past all of that, the image is soft.

I'll be interested in seeing anything else they have to offer. I remember hearing about RED when it was nothing more than an idea.

However 23 stops... nothing in this image shows me that.
 
bull on this one! you can't have the color card showing the same value as the inside of the light reflector!
 
I think your misunderstanding the poster's info- he said the scene is lit by a 500 watt
source - that would be excluding the light source directed toward camera.
Shadows and highlights are consistent with this. The off camera light isn't that close to the subject- look at the light ratio between objects camera right and left. Even then there are too many unknowns. We need a little more data.
It isn't soft- look at the grid pattern on the light detail image. Besides, if this test is for latitude, it's not ideally lit and set up for critical focus assessment. There will be some plane of critical focus but it's hardly worth searching for. Not too shabby, though.

Obin, my black and white stills work using staining and compensating developers tells me you can have the inside of the reflector contained to the extent of showing the nearby card at these values- and the card isn't the same value- and we don't know what light has been pumped onto it. I'm saying this is not impossible, but...
 
Not sure why so many are hammering down on this. For a pure technical dynamic range indication this appears to be incredible. It will be good to see properly lit images from this camera.

For all I know about this camera its images could look like a crap sandwich with a side order of crap. But if that still has not been doctored then it would definately have an unbelievable amount of dynamic range.
 
Sorry Bill, I disagree on one thing.
Michael writes: "Apparently the light in the images, a 500 watt halogen, is the sole light source". I can only conclude he means the lightsource is in the picture.

Finner - You are right we should be open and curious about new developments. Only this picture - regrettably - does not prove "an unbelievable amount of dynamic range", because it's not clear how it is lit.

Just a simple outside shot in de the sun with lot's of shadows and contrast would tell me a lot more.

So I would love to see more footage from this camera.

Cheers,
Joost
 
Lens flare?

Lens flare?

With the light pointed into the lens you get lens flare that lifts the shadow areas, in fact if you put bias lights into your RED ONE you could get a A+B=C curve that expands the dynamic range, but would give too much noise in the dark areas since the sensor area is too small.

Shooting with normal lenses, the dynamic range is limited by the lens flare since lens flare can reduce the bit deltas for detail in the darker areas. Lens flare can also pull dark areas up out of the compression and sensor large steps at the bottom of the A2D, so a little can help and too much can hurt...

If people start trying to get clean 23stops from a single lens, they will need fewer element groups and better coating. It should be possable to make a single group cemented multi-element lens with just two air surfaces that would have better flare values, the two surfaces being EBC coated etc.

Anyway, you should be able to get more bits now using two synced RED ONE in an HDR rig if you need to shoot without lighting control.
 
Finner said:
Not sure why so many are hammering down on this. For a pure technical dynamic range indication this appears to be incredible. It will be good to see properly lit images from this camera.

For all I know about this camera its images could look like a crap sandwich with a side order of crap. But if that still has not been doctored then it would definately have an unbelievable amount of dynamic range.
Click to expand...

I disagree. If you use multiple lights, as we all agree the original photographer did, you could recreate this image with a RED ONE, or hell, with enough finesse you could get a DVX100 to do it (res excluded)

Being able to see into the shadows and still see the filament would indeed be incredible, but if you add enough light to the rest of the scene so that you can expose for the filament, it's not that big of an accomplishment. right?
 
I am not against anything. I am simply of the mind set that this photo with limited to no support information gives me nothing to get excited about.

Show me clear evidence and my mind set is a different story. I was the same towards the RED ONE when it was first announced.
 
To clarify, I believe they said the light in the image was the only source, but I could be mistaken. There are some mysteries here, but I'm not sure that Thompson would come out with an outright hoax at a high level event like the HPA.
 
To me, it looks like classic HDR.

Take *multiple* exposures.
Merge them with HDR software... which will also do tonemapping for you.
Now you have a HDR image. Any camera can do this*. (*Provided that it is sensitive enough.)

So I'm not sure what this image is really supposed to show, unless you want to use a video camera on only non-moving subjects.

1b- OR... they are doing temporal noise reduction tricks. But again... would you want to use the Infinity on non-moving subjects?

2- To get 23 stops from a camera in a single exposure, you'd probably need a 23-bit A/D...

3- I could very well be missing some context... which I think we are missing.
 
Slew rate?

Slew rate?

GlennChan said:
2- To get 23 stops from a camera in a single exposure, you'd probably need a 23-bit A/D...
Click to expand...

I don't think that at the pixel frequencies required for Digital Cinema the pre-amps in/on the sensor could have a slew rate that would allow 23bits of accurate data. In a Bayer sensor if you have four pre-amps you can reduce the color de-saturation but you still get low pass and overshoot from the pre-amps so you would not be getting true 23bits for every pixel on all subjects?
 
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