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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 :)

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Ryan Nichols

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I’m on set shooting R1 MX. I’m having focus issues. When I shoot 4.5k it is sharp as a tack. Then I go into 2.k 2:1 and its fairly out of focus. Is that a problem of shooting 2k or am I not calibrating something correctly? Shooting redcode 42.

Thanks!
 
2K is softer than 4.5K, certainly - it is no longer getting the oversampling benefits. However, we have shot a lot of 2K overcranked 100FPS and can usually get a passable result at final 1080 output with some sharpening in post and a little grain. I suspect you are simply seeing the drop in resolution, oversampling and thus relative softness of 2K vs. 4.5K, not an actual bug or problem. Also, 2K can be pretty revealing of optical weaknesses in lenses, in my experience, given the crop factor.

What are you viewing this on set with? Did you look at it in RCX, or some other tool onset yet?
 
I’m using the 5.6” monitor and a 22” in monitor. It looks tack sharp in both when doing 1:1 and normally. Maybe it’s just the resolution drop? I didn’t even notice until I started doing some quick viewing in RCX and exporting stills. In the monitor it’s very sharp though.
 
Ryan Nichols said:
I’m using the 5.6” monitor and a 22” in monitor. It looks tack sharp in both when doing 1:1 and normally. Maybe it’s just the resolution drop? I didn’t even notice until I started doing some quick viewing in RCX and exporting stills. In the monitor it’s very sharp though.
Click to expand...

on the small 5" or 5.6" monitor it WILL look sharp....if you are saying on the larger 22" monitor it's also sharp, then that's plain strange. Guess if you are doing 1:1 and a critical focus and in the end it's NOT sharp, then might be some OTHER problems....on RED ONE i NEVER shoot over 90 to 96fps....for some reason at say 120.....gets even softer....but as someone alreadly mentioned--add back some sharpening in post. But as long as you are checking focus on set....i can't see anything you're doing wrong...

Anson, point taken. I am often going back from 4k to 2k and on same shot I'll re do a critical focus at 2k....and focus EXACTLY as i want it....knowing how it is a crop of the sensor and end up being slightly softer.
 
I can't explain it, but I have found the Red One to be a touch soft @ 2K 120fps when shooting subjects that are 10-20 ft. away from camera with a wide lens. Maybe I'm trippin, but that is what I've noticed.
 
It looks great on the 22” monitor. Even with the 1:1 zoomed all the way into the eyes.
 
24 FPS timebase or 100FPS framerate at 24FPS project timebase? If you do not NEED to overcrank >60FPS, shooting at 2K should be avoided, its softer (less resolution. A lot less). But you probly knew that. Just checking.

I mirror what other posters have said - if you nail focus on your monitor punched in a t1:1, it looks good on the client/larger monitor, and just looks soft in RCX, then you are just experiencing, well, reality. Not a problem. 2K footage in RCX looks soft, yep, compared to 4K, etc. Sharpen a hair and add some grain, and it is usable, but will never be nearly as crisp as 4K. That's why we love shooting 4K! Shooting 2K on RED is like running your Ferarri at 35 MPH - but of course, it gets you 100FPS.
 
Indeed. I guess it is just reality. It’s ok though. I do love shooting 4k but for this one thing I needed a little more time in between card swaps as I’m still on cf cards. Oh well, lesson learned. Any experience shooting 3k or is that a poor choice as well?
 
Clint Lealos said:
I can't explain it, but I have found the Red One to be a touch soft @ 2K 120fps when shooting subjects that are 10-20 ft. away from camera with a wide lens. Maybe I'm trippin, but that is what I've noticed.
Click to expand...

you are not tripping (well - as far as I know). Wide angle lenses at 2k are too be avoided. It will always look slightly soft. Add a gradient in the background and a dolly move and you are in pixel hell :-)
 
fixed bandwidth

fixed bandwidth

As I understand REDCODE its fixed bandwidth regardless of the fps, so the more fps you have the less bandwidth you end up with per frame.

So when there is less bandwidth per frame, the ratio of bandwidth spent on edge sharpness vs. low detail areas can become more obvious.

If you shoot with wide angle lenses you get edge detail scattered all over the frame area and that eats up bandwidth.

Its better when you have lower bandwidth per frame to isolate the subject with shallow DOF using longer lenses, that way more of the edge bandwidth will be spent on the primary subject and less on the background or surroundings.

Also using raking light to highlight the edges will help the compressor concentrate on the high contrast edges rather than lowering the edge detail in favor of small texture all over the frame area.

So try this:

Use a longer lens like a 75mm.

Set it at prime stop of f/4.5 to maximize edge sharpness on the subject.

Use ND + IR cut to control the exposure while leaving the shutter at "360", 345.6, 288, 180, 172.8 or 144. (so there is motion blur on the background as you follow camera on the subject)

Use raking light and rim lighting to highlight the edge contrast on the subject but not the background.

Have the background out of focus enough to reduce its drain on the per frame bandwidth.

As mentioned focus as best you can on the primary subject while having everything else soft.

Shooting with a black background eliminates most of the bandwidth used by the background and makes more bandwidth for the subject.

Compare the live view with the playback to see what difference you can see.

Increase the OLPF compensation, and run the images through a chroma low pass filter to reduce any added artifacts.

Try NEATVIDEO (tm) etc. to reduce added artifacts and noise from the extra OLPF sharpen (i.e. Temporal noise reduction).
 
Are you viewing playback through the camera or are you looking at the R3D's on a computer? If you're watching the playback from the camera that is the problem. The in-camera debayer/demosaic/etc/etc isn't very powerful and as a result your footage will look fuzzy and out of focus. But if you look at it on your computer it should look fine.
 
That's crazy! Because I had the same exact problem today. Was shooting at the wide end of a zoom at 2k 120fps and something didn't seem right. It looked like I was NOT able to nail focus at infinity. Believe me I've shot plenty of 2k and I know how soft it is compared to 4k but this was NOT it. It's one thing to know that you've nailed focus but the footage just looks a bit soft over all but it's a totally different for it to literally look like the backfocus is completely FUBAR and even at infinity your furthest subjects are not in focus, nor at anywhere else. I have yet to see the footage on my computer so we'll see tomorrow after I unload it whether it was the in-camera demosaic / debayer as some people have said or what.
 
2K 120fps is noticeably softer, due to increased compression. If you're shooting 2K @ 24fps, then it won't be any more soft than 4K @ 24fps and the same RC setting. Of course, at 2K there's really no extra resolution to oversample with and create inherent sharpness when you size your image. There's no in-camera sharpening happening on RED, at any resolution, either... People tend to identify 2K as soft, mostly because they're always working with 1:1 pixels when in post or delivering/viewing it. Differing lens choices when shooting 2K can also have an effect on apparent sharpness. But in most cases, when it all comes down to it, 2K is just as sharp on the RED One as 4K. For some reason people don't tend to look at 4K in 1:1 pixel view.... Gee, I wonder why.
 
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