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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 :)

Sharpening... ugh?

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Graeme Nattress said:
...As for sharpening - I think it's vital that sharpening be done with the output format in mind - and also, very carefully, with caution...

Graeme
Click to expand...

Caution, and a lot of it !!!!!!

I hate sharpening...the visible edges...

For those (like me) who like film, edge enhancement looks artificial.

From what i've seen so far from RED, the "true" resolution is so high, that it does not need any sharpening.
 
Sharpening can be done so it doesn't look bad. However, really it should be, theoretically, in the best possible of worlds, done by the output device and be defeatable.

Graeme
 
That's the thing to keep in mind -- sharpening gets applied in a lot of display and distribution formats. Even a dub from an HD deck to a Digi-Beta decks adds edge enhancement as a default. Many display devices have some form of edge enhancement. Laser recorders can add it during a film-out. So don't overdo sharpening at an early stage because then it can get accumulative.

Even film has its own form of photochemical edge enhancement around the dye clouds/grains.
 
Definitely, sharpening is the last step in post you do.
I Agree with David, it gets accumulative and often with disastrous effect.
If applied, then The latter the better.
It's quite different for still images thought, you can permit your self to go much farther wit a lot more control.
 
Graeme Nattress said:
There is no "troubled" with 2k cropped. It looks great, especially at high fps for nice slomo.
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To be fair, if you need >60fps from your RED, there's no way to do it but to use the windowed mode. But even in a 1080 finish, the difference in resolution between the 4K footage and 2K windowed footage I've shot is very noticeable. I think many are curious to see how the scaled footage holds up, because besides the obvious benefits of maintaining your 35mm FOV, I think the scaled footage will match the 4K content visually much more closely. Right now anyway, I wouldn't intercut between windowed and full-sensor footage in a project.

Also, David's got it spot on with his last comment - sharpening can always be (and often is) added in the final step before distribution, but once you add it to your master renders you can't get it out. Better to leave it as the last link in the chain than add it and be stuck with the choice.
 
Also a lot of video pipelines add sharpening on top of compressed footage so then you get a bunch of nice sharp DCT boxes. Yay!

Other wonderful places for sharpening: Greenscreens, noisy footage...
 
Häakon said:
To be fair, if you need >60fps from your RED, there's no way to do it but to use the windowed mode. But even in a 1080 finish, the difference in resolution between the 4K footage and 2K windowed footage I've shot is very noticeable. I think many are curious to see how the scaled footage holds up, because besides the obvious benefits of maintaining your 35mm FOV, I think the scaled footage will match the 4K content visually much more closely. Right now anyway, I wouldn't intercut between windowed and full-sensor footage in a project.

Also, David's got it spot on with his last comment - sharpening can always be (and often is) added in the final step before distribution, but once you add it to your master renders you can't get it out. Better to leave it as the last link in the chain than add it and be stuck with the choice.
Click to expand...

Hi Haakon,
Thanks for an honest comment on image quality for 4K full-sensor and 2K
windowed. I take my hat off to you and other Red camera owners who give
good honest information on this product.
From footage I've seen the 2K windowed stuff stands out like dog's
testicles, but everyone at Red says it looks fantastic. Hmmmm.
This is a problem I think and the fact that Jim is now suggesting sharpening
for 2K windowed only confirms it.
Mezmo.
 
Graeme Nattress said:
Sharpening can be done so it doesn't look bad. However, really it should be, theoretically, in the best possible of worlds, done by the output device and be defeatable.

Graeme
Click to expand...

I agree with the second sentence 100%
 
mezmo said:
Hi Haakon,
Thanks for an honest comment on image quality for 4K full-sensor and 2K
windowed. I take my hat off to you and other Red camera owners who give
good honest information on this product.
From footage I've seen the 2K windowed stuff stands out like dog's
testicles, but everyone at Red says it looks fantastic. Hmmmm.
This is a problem I think and the fact that Jim is now suggesting sharpening
for 2K windowed only confirms it.
Mezmo.
Click to expand...

Don't get me wrong, 2K is still greater in resolution than the plethora of other 1080 cameras out there, and my guess is that RED in 2K would be pretty comparable to a HPX3000 or the like. I did a recent comparison test with RED (in 4K) and the HPX200, and the results were astonishing... you really don't realize how much nicer RED is until you do an A/B test and see the gaping differences. However, it is my feeling that the windowed format pales in comparison to the full 4K raster the camera can record onboard - let's face it, it's 4 times less total area - and if we could record faster speeds in 4K no one would even consider shooting the format. In fact, I honestly believe that once 2K scaled at 60p becomes a viable option, the demand for 2K windowed will decrease immensely. I give RED major props for accomplishing everything they have; I'm a proud and excited RED owner. But shooting windowed and sharpening the footage won't be a part of my standard workflow.
 
I see a bit of experience working with RAW images from still photography is the gold here.
For anyone looking how to get most out of RAW footage I recommend to buy few books by Scott Kelby about digital photography.
I am still looking for the good book about dealing with the FOCUS and motion. Anybody know some good books on this subject?
 
Remember 2k at 1:1 pixel on your monitor looks exactly like 4k 1:1 pixel on your monitor, just with the 4k having more image area. I see very nice edge definition on both 4k and 2k in this regard, and both respond nicely to a very small amount of sharpening.

The difference is the display of the final image. Different resolutions get different characteristics as they are displayed, and there's enough difference between 2k and 4k to warrant some difference in processing, with the end display media being accounted for.

Graeme
 
Absolutely. And different print sizes or screen sizes too!

Graeme
 
I've been working on digital stills for some time and have found that Niks pro sharpener works a ton better than unsharp mask. At least for still frames. I wonder if it works with any video software like AE?
 
Graeme Nattress said:
Remember 2k at 1:1 pixel on your monitor looks exactly like 4k 1:1 pixel on your monitor, just with the 4k having more image area.
Click to expand...
Hi Graeme,

Have you implemented a 1:1 pixel view yet from the camera? The 2x zoom-in feature is helpful, but still leaves a bit of room for play. I'd love a true 1:1 view, even with a 720p screen.
 
Let's re-think again about this opinion quoted below:

"...the captured image is sharp or it is not. Some manipulation in the darkroom or at the printing stage (or in digital post production) might save a slightly unsharp picture, but basically the sharpness problem is a matter of good optics, accurate focusing and the characteristics of the film emulsion/(RAW)developer interaction.

Basics of image quality

For a long time, it has been noted that the image quality is based on a few parameters, tonality or gradation of the differences in light intensity (for the plasticity of the image), the crisp delineation of the subject shapes (also known as the acutance of the image) and the clean recording of the fine textural details of the subject surfaces (also known as the definition of the image).

Optical and scientific analysis has indicated that the contrast transfer function (MTF) is a reliable measure of the optical capabilities of a lens or lens/film combo to record these aspects of the image. Since then we are all familiar with the MTF graph, which essentially has the same universal shape: contrast is high when few image details (linepairs per mm) are recorded and contrast is low when many lp/mm are recorded. Between both extremes the curve has a downward sloping shape.
...
It is also well known that the mathematical manipulation of the numbers can enhance the basic features of an image: detection of a subject contour line is easy and it is simple arithmetic to change the values of individual pixels. This is how sharpening algorithms work: the original image is blurred slightly, then the blurred version is compared with the original version on a pixel for pixel basis. If a pixel is brighter (has a higher value) than the blurred version it is lightened further and if a pixel is darker than the blurred version it is darkened more. Thus the contrast between pixels (image details) is enhanced and we can see the difference more clearly. Note that no additional detail is reconstructed: only the basic information is exaggerated. Here we can see the validity of the Leica claim that the lens still has to very good otherwise the details can not be recorded and afterwards not reconstructed.
...
The main questions I am interested in can be stated as follows:

(1) what is the relation between the optical performance of the lens and the post processing algorithms.

(2) what are the differences between these algorithms as executed in the raw converters."

"Raw developers, sharpness and lens quality"
by Erwin Puts

MORE > > >
 
Interesting article.....

Graeme
 
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