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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 :)

2/3" for Action Sports...?

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Brant Williams

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Overcranking is quite important for action sports work, allowing stretching and compressing of time frame for effect. As such, the 120 fps of the 2/3" is VERY enticing. Given the current specs on the S35 (overcrank ability limited), I end up evaluating the 2/3" vs. the Red1.

Even without considering cost, the 2/3" looks like it actually will offer more flexibility and performance when overcranking at 120 fps vs the R1. When shooting 120 fps, the R1 is windowing the sensor to 2K, so it is essentially a 12.2mm x 6.85mm sensor, correct?..whereas word is the 2/3 will be able use the whole sensor at 120 fps. I will believe when I see it...but I sure hope they can pull it off!

Some Vertical Angle of View Comparisons. I chose an 11mm lens focal length, since that is close to the bottom end of the range without getting curvy distortion. That...and the fact that I just ordered a Tokina 11-16!:

Vertical Angle of View:
R1 2K Windowed, 11mm lens: 35 degrees
2/3", 11mm lens: 46 degrees
DX, 11mm lens: 71 degrees
Full Format, 11 mm lens: 95 Deg

Or, to equate the R1 2K and 2/3" angles of view to required lens focal lengths on DX and Full Format:

R1 2K Windowed at 11mm frames like:
26mm DX
38 mm full format

2/3" at 11mm frames like:
18.5.mm DX
28 mm full format

The 2/3" barely qualifies as wide...while the R1 2K windows does not even get close. Looking at it another way, if you want to be up close with the R1 at 2K, you will have to be using a very short focal length, which will really take away any control of DOF. The 2/3" suffers from the same issue, but not nearly as bad when comparing 120 fps performance.

Am I evaluating this correctly?
 
If you are shooting action sports the deeper DOF of the 2/3" format will be a welcome plus for following focus on fast moving subjects IMO. Yes the fast frame rates on the 2/3" will be at full frame size, no crop.
 
David,

I think you missed my point. Everyone talks about how with the 2/3" sensor DOF control is lost (on the short end). My point was that if you are talking about overcranking, that is not true. The 2/3" will actually offer more DOF control (by that I mean you can keep DOF shallower) than the Red One.

Lets say I am going to shoot 120FPS with a 24mm lens on a 2/3" sensor, and can use the whole 2/3" sensor. To frame the shot the same on the R1, I will have to go to a 17mm lens because it windows the sensor to 2k (50%). The R1 will actually limit DOF control more than the 2/3" when shooting in 2K high fps modes.
 
There is not that much difference between 2k on a Red 1 and 3k on Scarlet. The 24mm will actually be slightly wider at 2k on R1 than on 2/3" 16:9. Same DOF. Both can be covered by a 16mm format lens.

attachment.php
 
Brant Williams said:
David,

I think you missed my point. Everyone talks about how with the 2/3" sensor DOF control is lost (on the short end). My point was that if you are talking about overcranking, that is not true. The 2/3" will actually offer more DOF control (by that I mean you can keep DOF shallower) than the Red One.

Lets say I am going to shoot 120FPS with a 24mm lens on a 2/3" sensor, and can use the whole 2/3" sensor. To frame the shot the same on the R1, I will have to go to a 17mm lens because it windows the sensor to 2k (50%). The R1 will actually limit DOF control more than the 2/3" when shooting in 2K high fps modes.
Click to expand...

The R1 sensor is significantly more than twice the size of 2/3", however.

The Scarlet 2/3" will make a pretty great camera for sports situations, though.
 
So when the R1 windows down to 2K....it does not just window the sensor to 50%?
 
Brant Williams said:
So when the R1 windows down to 2K....it does not just window the sensor to 50%?
Click to expand...

Yes it does. The graph I linked above is to scale for R1 2k and the 2/3" sensor.
Diagonal measure for R1 2k is about 12.7mm, for Scarlet at 16:9 about 11mm. So for the same focal length lens R1 2k would cover a slightly wider angle. But same lens, same f stop = same DOF.
 
My confusion originated from the fact that I mistakenly assumed 2/3" sensor was 16mm...it is actually 10mm wide....
 
Brant Williams said:
My confusion originated from the fact that I mistakenly assumed 2/3" sensor was 16mm...it is actually 10mm wide....
Click to expand...

2/3" refers to the diameter of a vidicon tube with an image target approximately the size of 16mm film TV projection aperture, which is where the format originated. It allowed early TV cameras and 16mm film cameras to share the same lenses, one factor in its overwhelming popularity for TV production.

I prefer to think of Scarlet 2/3" as a digital 16mm camera.
 
Recordable area on the 2/3" Mysterium chip should be 10.14mm x 5.7mm (3K 16:9). Full aperture 16mm film is typically 10.26mm x 7.48mm. So they're pretty darn close. I think a lot of 16mm glass is going to see a revival with the 2/3" Scarlet camera.

The 2K area on the RED One or the larger Mysterium chips is 11.06mm wide, which isn't a whole lot bigger, or not enough to matter in most situations and most 16mm lenses will still cover the format. The difference in FOV isn't significant enough to force different DOF considerations between 2K on the S35 sensor vs. the 2/3" sensor. But what should come into consideration here is resolution. The 2/3" sensor has much more densely packed pixels. You get 3K within roughly the same area (slightly smaller). RED One 2K falls right in the middle of 2/3" or 16mm and super-16mm formats. RED One 3K doesn't match up with anything.
 
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Jeff Kilgroe said:
Recordable area on the 2/3" Mysterium chip should be 10.14mm x 5.7mm (3K 16:9). Full aperture 16mm film is typically 10.26mm x 7.48mm. So they're pretty darn close. I think a lot of 16mm glass is going to see a revival with the 2/3" Scarlet camera.
Click to expand...
The last time I saw any specs for the 2/3-inch imager, it measured 10.1 x 5.35 mm (3K at 1.89:1, 2.8K at 16:9).
 
RED hasn't released any official specs. Originally the sensor was announced as having a ~3 micron photosite size. Lately, they have been saying 3.3 micron... The dimensions I gave assume 3072x1728 @ 3.3um.
 
Will it be doing 3k 16:9 or will it be as the original spec, 3k digital cinema format and 2880 x 1620 for 16:9? At 3.3 microns, 3k 16:9 doesn't quite fit within the 2/3" reference image circle.
 
David Rasberry said:
Will it be doing 3k 16:9 or will it be as the original spec, 3k digital cinema format and 2880 x 1620 for 16:9? At 3.3 microns, 3k 16:9 doesn't quite fit within the 2/3" reference image circle.
Click to expand...

As far as I know it does 3K 2:1 (3072 x 1536) natively. 16:9 will probably be slightly smaller than 3K.
 
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