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cjackson
2015-Dec-18, 12:07 PM
The camera will be 3.2 gigapixels. Could you put that into perspective? How does it compare with the most powerful movie cameras?

DaveC426913
2015-Dec-19, 02:43 AM
As countless Best Buy reps tell me over and over: pixel count isn't everything.

Does the LSST have a sepia filter? Red-eye removal? Noooooooooo...

Shaula
2015-Dec-19, 06:52 AM
A quick bit of googling (I know nothing about movie cameras!) suggests that the ALEXA ARRI series are representative of good cameras.
http://nofilmschool.com/sites/default/files/uploads/2014/01/Cinematography1.jpg
http://nofilmschool.com/sites/default/files/uploads/2014/01/Best-Picture.jpg
http://nofilmschool.com/sites/default/files/uploads/2014/01/Directing.jpg

One of the popular ones is the ARRI ALEXA M:
https://www.arri.com/camera/alexa/cameras/camera_details/alexa-m/subsection/technical_data/
That would be a 6.2 megapixel camera.

The top end ones at the moment seem to be things like this:
https://www.arri.com/camera/alexa/cameras/camera_details/alexa-xt-studio/subsection/technical_data/
Which would be a 7.5 megapixel camera.

So the LSST has about 500x more pixels than either.

(I thought the movie camera resolution sounded tiny until I did the math - on a typical 80 foot screen a 3414px image would lead to about one pixel per 7mm - which actually sounds quite believable)

ngc3314
2015-Dec-19, 08:36 PM
As countless Best Buy reps tell me over and over: pixel count isn't everything.


Burt remember - just because a Best Buy salesperson says it doesn't make it wrong. There ready other other sensor properties than can override pixel count for various aplications.

DaveC426913
2015-Dec-19, 09:03 PM
Burt remember - just because a Best Buy salesperson says it doesn't make it wrong.
Oh, I know.

antoniseb
2015-Dec-20, 02:23 PM
... So the LSST has about 500x more pixels than either. ...
Most movies these days are shot in Cinema 4K which is about 9 megapixels, though there are some cameras (e. g. Red Epic) out there shooting more, 6K & 8K, so up to about 40 megapixels. I'd like to point out that these cameras take up to 100 frames per second, while the LSST will be a much slower frame rate, so the pixels per second will be about the same for the LSST and the newest generation of cinema camera.

cjackson
2015-Dec-23, 03:52 AM
How would it look if you tried to shoot a movie with the LSST camera?

Shaula
2015-Dec-23, 05:19 AM
How would it look if you tried to shoot a movie with the LSST camera?
I'm not sure that is a simple question to answer. The FPA is only one small component of the camera system. The electronics back end and the software controlling it would be completely different to a movie camera because it is optimised for a different job. Some examples - the readout array might not have the capacity to support a high enough frame rate, there might be hardware limitations to integration time, there might be autogain or some form of DR mapping scheme that doesn't suit the human vision system. It might not be able to focus at less than infinity!

So I think you would have to rebuild the camera to the point where it would not be the LSST camera.

antoniseb
2015-Dec-23, 01:06 PM
How would it look if you tried to shoot a movie with the LSST camera?
Following up on Shaula's great reply: It depends on what it is a movie of. If the LSST is making a movie of the night sky, it would look great, but with a slow frame rate, so whole meteor trails would appear in a single frame. If you were shooting a barroom scene trying to get detail of the rims of every pore on Bradley Cooper's face, the LSST would be out of focus, with huge depth of field issues, very difficult to point, and completely overexposed (white on white final images), possibly to the point of damaging the sensors. The high pixel count is not enough (by itself) to make it a good movie camera.