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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Understanding 3k compared to HD

Kalani Prince

Kalani Prince

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Thought this might be helpful to new potential Scarlet buyers in understanding just how much more visual information you will be getting from Scarlet. I remember how confusing it was when I was trying to understand sensor size in relation to resolution size.
This frame is straight out of a Canon 5D Mark II (in video mode) with a full frame sensor. You can see that the Scarlet image is much larger even though it's coming off a much smaller sensor.
* Hey guys, I edited the image to reflect Scarlet @ 3k.. I had no idea the Premiere preset was for Red One @ 3072X1728. See, I'm still confused ; )

 
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Thus, if someone delivery format is HD, - 3K Scarlet is all is needed with oversampling effect included!
 
I think Scarlet 3K is 3072x1620.
 
Kalani Prince said:
Hmm, this is straight out of Premiere's preset for Scarlet @ 16X9.
Click to expand...

That's the preset for Red1 3k 16:9.

Scarlet 16:9 is 2880 x 1620. 1.89:1 cinema wide screen is 3072 x 1620.

So far all of Red's sensors are native digital cinema wide screen format, not HDTV format.

attachment.php
 
Eric Rodemann said:
I think you then have to do something similar to the HD frame as well if you want to compare apples to apples, right?
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yes, although even if you left the HD at 1920x1080, I still think the 2.4K would make a strong visual case for how much more information you have to work with.
 
Eric Rodemann said:
I think you then have to do something similar to the HD frame as well if you want to compare apples to apples, right?
Click to expand...


TL;DR

Basically, I think you are right. Most HD cameras don't resolve an actual 1080p image just as 3K readout from Scarlet won't actually resolve a 3K image. The trouble is, different HD cameras resolve different amounts of information, making it impossible to standardize for the sake of comparison. Fortunately, RED is pretty solidly at ~78% resolution after debayer.

Finding apples to apples is difficult until we talk about specific cameras.

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Sort of...but depending on the image acquisition strategy employed by the camera.

I look at these resolutions "1080p" and "3K" from an acquisition standpoint as buckets. Lots of cameras have 1080p buckets, but most don't fill them very full of real information. We all know about HDSLRs and the fact that they don't resolve a full 1080p. Likewise with many other cameras - Alexa, EX-series, etc.

In order to compare the image from different cameras on an "actual resolved resolution" level, you'd need to know the actual resolved resolution and then find some way of downscaling that properly represented that resolution.

This can be done simply for RED by debayering to the proper resolution.

Trouble with "video" is that it has already been processed from the sensor, meaning that lines have been skipped, stripes have been combined, pixels binned, etc.

So, as I see it, it will never be apples to apples, exactly. Maybe oranges to tangerines or grapefruits.

--

That being said, comparing buckets to buckets can be somewhat useful. The 1080p bucket is rarely (if ever) completely full of "real" resolution. Likewise, the 3K frame isn't fully resolved either. The problem is that, with RED, we know that the real resolution of the frame is ~78% of the bucket. With 1080p, we have no idea because it depends so much on the camera - a 7D, an EX-1, an Alexa, and an F23 will all fill the 1080p bucket to one extent or another.
 
Jason Madeja said:
I'd kinda like to see that frame comparison after a full debayer. 2.4K is it?
Click to expand...

After a full quality debayer the frame size is still 3072 x 1620 RGB pixels. It is the overall system optical resolution that is less when measured on a chart. That is measured in lines per picture height/width, not pixels. Debayer doesn't alter the defined pixel resolution of the file at all unless you scale it or crop it to something different for output.
 
David Rasberry said:
After a full quality debayer the frame size is still 3072 x 1620 RGB pixels. It is the overall system optical resolution that is less when measured on a chart. That is measured in lines per picture height/width, not pixels. Debayer doesn't alter the defined pixel resolution of the file at all unless you scale it or crop it to something different for output.
Click to expand...

Can we make this a sticky somewhere? :cheers2:
 
I think that image is a bit misleading and some people will think that Scarlet sensor size is that much bigger than 5D's. You should have added region on the picture that shows the area Scarlet would shoot from the same distance with the same lens.
 
Derek S. said:
I think that image is a bit misleading and some people will think that Scarlet sensor size is that much bigger than 5D's. You should have added region on the picture that shows the area Scarlet would shoot from the same distance with the same lens.
Click to expand...

Other than the fact that the OP got the Scarlet sensor resolution slightly wrong (should be 3072 x 1620, as has been pointed out), he correctly represents that the Scarlet image is bigger than the motion image of the 5D, or any HD image, for that matter. I don't think he was trying to say anything about the size of the sensor itself, or the FOV. After all, FOV can easily be changed with a different focal length while resolution is "hard wired."
 
With the HDR upgrades in processing power, I wouldn't be surprised if it can do even 180 fps. :)

Which is the sensor`s maximum, if I'm not mistaken.
 
Derek S. said:
I think that image is a bit misleading and some people will think that Scarlet sensor size is that much bigger than 5D's. You should have added region on the picture that shows the area Scarlet would shoot from the same distance with the same lens.
Click to expand...

Hi Derek -

I agree with Terry, here. The pictures above aren't showing relative sensor areas or FOV. They are showing the relative size of a 1080p frame and a 3K frame which will always be the same since 1080p and 3K are defined by a set of constant integers representing pixel dimensions:

1920x1080 for 1080p

3072x1620 for Scarlet 3K

Looking at it this way, it doesn't matter what is in the frame or what the FOV or DOF looks like - the 3K image will have greater spatial resolution.
 
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