FS7: Crop mode (centre scan)

Yeah, as Doug said. I guessed this might come since the wording for high frame rate in current firmware is "Full Scan"
 
morgan_moore said:
Eng lens with inbuilt doubler engaged?
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Nope. It takes more hardware than that because a 2x converter does not increase the size of the image circle. You have to actually enlarge the circle of light so it physically covers the super-35mm sensor instead of just 2/3". If you are interested, I wrote a quick and dirty article on about 2K center scan in issue #2 of Sony's Cine Alta magazine.
https://www.dropbox.com/sh/l40te35nuwzf8s4/by5SEJTrBv
Page 65
 
Yeah, you're right. I mispoke. In fact, you don't even need to cover the full 35mm sensor for 2K center scan anyway. That's the whole point of it. For some reason I was thinking of 4K with an ENG lens.
 
For 1080 what would also be nice is an intelligent sensor center-crop "punch-in zoom" Obviously it wouldn't be as sharp as the 4k downsample of the full frame, but definitely would be useful for a number of on the fly scenarios in ENG and corporate scenarios.
 
I apolgize if I am misunderstanding your post, but you have described exactly what Center Scan is all about. It's like the DX and FX modes on a Nikon full-frame SLR.
Read my article. And the center cut comes with no loss of sharpness or loss of light. It's a great feature on the F55 and I use it all the time. Turns my RED 300mm into a 600mm f/2.9. Makes my Zeiss 15.5-45mm a 31-90 at the touch of a button. Great for run and gun.
 
Centre Crop is a great feature. I use All Files to make it a two-button-press operation (which is moderately painless). Having to wait for the whole camera to reboot is a pain in the proverbial though.

Best uses for it are for super-close focus work, and for aliasing-free HFR work. Also great when you're short on time for a close-up, and don't have time to change lens, change camera position and re-find focus marks.
 
Doug Jensen said:
I apolgize if I am misunderstanding your post, but you have described exactly what Center Scan is all about. It's like the DX and FX modes on a Nikon full-frame SLR.
Read my article. And the center cut comes with no loss of sharpness or loss of light. It's a great feature on the F55 and I use it all the time. Turns my RED 300mm into a 600mm f/2.9. Makes my Zeiss 15.5-45mm a 31-90 at the touch of a button. Great for run and gun.
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I'm not sure if this was in response to me. If it was, then - I guess my uncertainty is the implementation. For instance, I'm not sure whether this was intended just for high frame rate, or also as a mode for regular speed shooting, and then whether it would be it's own mode, or whether it would be available instantaneously. The PXW-FS7 certainly does reboots for a lot of mode changes, so I wasn't counting on a implementation that would be fast and easy with not rebooting. If you're confident it won't, that's certainly excellent news.

Of course there wouldn't be a loss in light for using the center crop, but my understanding is that at regular frame rates (up to 60p) the camera's downscaling takes advantage of the entire 4k sensor to make the 1080p image naturally sharper. Given that it has 11.6 megapixels and a 1080p only camera like the F3 only has something like 3.36 megapixels, I'm not surprised when the fine detail on the FS7's 1080p is naturally sharper than the F3 even when both are recorded to 1080p. My thinking is that by using a center crop, the camera would lose this advantage (at least to an extent) and might not be quite as sharp as when using the full sensor. Mind you, I think there are numerous situations where this trade-off would absolutely be worth it, so I'm certainly not complaining.

As for high speed, again, I suspect it would come down to implementation, but since the high speed frame rates don't use every photosite anyway, using a center crop in high speed might very well be just as sharp as a full scan - for that mode.

Doug - I suspect you're better informed on this issue than I am, but hopefully that clarifies what I meant to suggest.
 
Damn.. They really are giving the FS7 all the features of the F5/55.

You guys will love it, fantastic feature for when there isnt time to change lenses or you just need to really reach out to 400mm +
 
Viddovation said:
I'm not sure if this was in response to me. If it was, then - I guess my uncertainty is the implementation. For instance, I'm not sure whether this was intended just for high frame rate, or also as a mode for regular speed shooting, and then whether it would be it's own mode, or whether it would be available instantaneously. The PXW-FS7 certainly does reboots for a lot of mode changes, so I wasn't counting on a implementation that would be fast and easy with not rebooting. If you're confident it won't, that's certainly excellent news.

Of course there wouldn't be a loss in light for using the center crop, but my understanding is that at regular frame rates (up to 60p) the camera's downscaling takes advantage of the entire 4k sensor to make the 1080p image naturally sharper. Given that it has 11.6 megapixels and a 1080p only camera like the F3 only has something like 3.36 megapixels, I'm not surprised when the fine detail on the FS7's 1080p is naturally sharper than the F3 even when both are recorded to 1080p. My thinking is that by using a center crop, the camera would lose this advantage (at least to an extent) and might not be quite as sharp as when using the full sensor. Mind you, I think there are numerous situations where this trade-off would absolutely be worth it, so I'm certainly not complaining.

As for high speed, again, I suspect it would come down to implementation, but since the high speed frame rates don't use every photosite anyway, using a center crop in high speed might very well be just as sharp as a full scan - for that mode.

Doug - I suspect you're better informed on this issue than I am, but hopefully that clarifies what I meant to suggest.
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Resolution and sharpness are two different things.
 
broughtonfilm said:
Resolution and sharpness are two different things.
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Yes, if we want to be terribly technical and talk like engineers. But if we're not engineers then those words have slightly broader meanings.

Resolution is also confusing when used technically, because we can talk resolution in terms of MTF, but resolution is also an appropriate word to discuss different frame sizes, and since we're discussing a camera with multiple frame size options, as well as in this instance multiple options for reading the sensor, this can all get quite confusing quite fast.

I apologize if my attempt to use laymen's terms did not read clearly for you.
 
Full scan with default 4K OLPF = image with heavy moire/aliasing in certain situations

Centre scan with default 4K OLPF = little softer (than normal scan) but nice clean image.

On F5/F55 there is a "HD/2K Modulation" feature that tones down the perceived sharpness of the image (in normal scan) a little which is pretty nice.
 
Viddovation said:
I apologize if my attempt to use laymen's terms did not read clearly for you.
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We're probably all guilty of misunderstandings in his thread. No big deal.
But let's look on the bright side - THE FS7 IS GETTING CENTER SCAN!! This is huge.
If the FS7 wasn't the best bang for the buck of any camera in history already, this takes it up another notch.
And I will be completely shocked if the center scan only applies to HFR. I'll bet we have it in normal shooting modes too.
 
marvinhello said:
Full scan with default 4K OLPF = image with heavy moire/aliasing in certain situations

Centre scan with default 4K OLPF = little softer (than normal scan) but nice clean image.

On F5/F55 there is a "HD/2K Modulation" feature that tones down the perceived sharpness of the image (in normal scan) a little which is pretty nice.
Click to expand...

+1
 
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