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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 :)

Novice needs some advice

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Gregory Sheffer

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Been shooting with my RED since June. I went the 2K route and bought a Ziess 12-120 s16mm lens. 4K just seemed like overkill for my type of production.

I just hired a guy to do some shooting in Wash. with his RED. First time I have worked with 4K footage. Here are two comparisons still frames. Both are 2K tiffs out of RED Alert and both are straight out of camera.

My footage:
http://www.inversionproductions.com/c-133_2k.tiff
RED build 15 – 2K 320 ISO. zeiss 12-120

His footage:
http://www.inversionproductions.com/c-133_4k.tiff
RED build 16 – 4K RED 18-50mm

When I make ProRes 1920x1080 files of the footage his stuff looks so much better. What is the reason for the discrepancy in sharpness and clarity in his footage compared to mine? It can’t just be the build. Is it the lens? Is it the difference between 2K and 4K?

Just wondering if I should look into the RED lens option and shoot 4K.
 
Well, your image is very low contrast. Contrast is one of the most important parts of perceived sharpness. Be sure to set your contrast appropriately with your curves when developing.

Beyond that, I've used the regular 16 version of that lens, the 10-100, and was not very pleased with it. Try adjusting the contrast, but also look at a 35mm coverage lens and shoot 4k.

For low end stuff, a stills mount and lenses might do you fine. You can get excellent still lenses for peanuts compared to cine glass.
 
Your grab has a bit of motion? Did you miss focus slightly?

4K is 4 times more resolution (not twice) than 2K.

All (or some) of the above should explain the difference.

Jim
 
Contrast does wonders

Contrast does wonders

gsheff said:
What is the reason for the discrepancy in sharpness and clarity in his footage compared to mine? It can’t just be the build. Is it the lens? Is it the difference between 2K and 4K?
Click to expand...

As Charles Taylor noted, one major issue with the 2K still is lack of contrast.

I took the images into Photoshop and found that there is neither any true black nor white in the 2K image. There is no photo information where the two red arrows are. The histogram should follow a path more like the blue line.

c133.histogram.jpg


There are a lot of digital photos that look just fine - until you compare them to something else. A simple adjustment to bring true black into the picture does wonders.

With two quick adjustmenta in Levels (this is by adjusting the curves in RedAlert/RedCine and in Levels or Curves in FMP) I was able to add some snap to the picture, and add true white as well. I also shifted the green/magenta curve a bit to remove a green cast I saw. There is more that could be done, but I wanted to keep this simple, in line with what is possible with RedCine/RedAlert.

I've posted a cropped version of my correction (just a piece of the whole shot), split with the original, at:

http://www.rockymountain4k.com/examples/c133.split.tif

The Levels adjustment in FMP is not so flexible as that in Photoshop, but there are third party plugins, and Color, of course, can do wonders.

Nelson
 
Jannard said:
Your grab has a bit of motion? Did you miss focus slightly?

4K is 4 times more resolution (not twice) than 2K.

All (or some) of the above should explain the difference.

Jim
Click to expand...

Twice as many pixels horizontally and twice as many vertically means four times as many pixels altogether, which means four times the data rate.

But that's still only twice the resolution or am I missing something?
 
Why not shoot 4K for your projects. Even if they are going out to just SD DVD its better to shoot in 4K than 2K, unless is a slow-mo shot. It may seem overkill for your projects. It might be like going after a fly with a bazooka...but at least you know you got the fly.
 
As Jim pointed out, 4K has FOUR TIMES the resolution of 2K. You will get much sharper, more detailed imagery when you shoot 4K and convert to 2K than if you just shoot 2K. Additionally, 4K uses 4x the sensor area for the shallow DOF of a 35mm frame, etc.. But that oversampling effect you get from shooting 4K to produce 2K can make a significant difference.
 
That 4K shot looks great. Doing the RED lens proud there. Sharp, very lifelike.
 
part of the shirt looks pretty sharp to me, the face isn't in focus I think, and there may indeed be some motion blur in the face, and, as everyone else has said, there isn't much contrast; but all in all it doesn't look that unacceptable, unless it is a very important moment, with a lot of concentration on the face
 
Martin Weiss said:
Couldn't resist but to give it even more punch. Obviously this is down to taste. But amazing what you can get out of this footage.

Focus is indeed a bit off...
Click to expand...

Awesome.

Andrew.
 
Jannard said:
Your grab has a bit of motion? Did you miss focus slightly?

4K is 4 times more resolution (not twice) than 2K.

All (or some) of the above should explain the difference.

Jim
Click to expand...

Focus ... resolution ... what it has in common with low contrast photography?
 
Almost feels like light on the lens. Not a sweet kind of flare but the low contrast variety. Left side 3/4 kick is the possible source?
 
My original question is more of a concern with what the camera is recording. I know this 2K image cleans up well. I want to know if the difference between shooting 4K is worth all the extra hard drive space, time processing the footage (RED Rushes took 48 hours to make 115 4K clips into 1080 prores files), and me buying more lenses. When I saw this 4K stuff I thought either I have a crappy lens or 4K is the way to go.

Here are two more comparison frames:

http://www.inversionproductions.com/c-133_2k.tiff
RED build 15 – 2K 320 ISO. zeiss 12-120

http://www.inversionproductions.com/c-133_4k.tiff
RED build 16 – 4K RED 18-50mm
 
4K is worth it, for all the reasons listed above (aside from the contrast / exposure discussion).

RedRushes should not be taking 48 hours to convert about 115 clips to 1080/2K ProRes. Obviously it depends on clip size / take length, but 4K 24fps into 2K ProRes should take about 3X real-time to convert on a current 8-core Mac Pro @ 3GHz.

So if it took 48 hours to process the 4K into 2K on a shoot, that tells me that you're dealing with any one or a combination of the following:

* You shot at least 12 hours or even 15+ hours of footage.
* Your computer and/ or drives are really slow.
* You have a problem with your computer and/ or drives used for the conversion.

That said, not everyone has a shiny new Mac Pro at their disposal. A Macbook Pro is going to be significantly slower -- I think even with outputting to a fast RAID, I still get about 12X real time on my Macbook Pro. It works for some things. But it's not a processing powerhouse and should not be treated as such. If you're stuck with a Macbook Pro or iMac as your workhorse system, then brute-force conversions within RedRushes before editing is probably not your best solution. But rather doing a rough offline with the proxies and then using an intermediate tool like Crimson Workflow so you only have to transcode the footage you need to complete your edit.

Hopefully this will change for the better once native R3D support shows up in our post tools.
 
gsheff said:
I know this 2K image cleans up well. I want to know if the difference between shooting 4K is worth all the extra hard drive space, time processing the footage...
Click to expand...

Your post (and the attached stills) seemed to be about the overall image quality, and the low contrast rendering of the 2K still seemed to be part of the problem. I see what you're asking now.

To me the whole point of the Red is being able to control DOF like 35mm, and that requires the full sensor. But it's really going to be a matter of taste - and budget. As you ask, is it worth a whole new set of lenses? Is it worth the additional time in production (and the cost of a good 1st AC) and in post. All of that costs more money (the storage space is the least of it, with terabyte drives going for $500 or so) for what is certainly a better overall image, but only you can decide if the increase in quality is worth the cost.

Nelson
 
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