View Full Version : What resolution do you render?

05-29-2015, 02:21 AM
I have been rendering alot of 1080p but im wondering is it really worth it when it comes to quality versus rendertime. 720p is alot faster to render no doubt but the question is will anyone notice that mutch of a diffrence if i scale it up after the render to 1080p and shapen it. :D How much can one cheat with resolutions before someone notices?

05-29-2015, 02:30 AM
Don't scale it up, it never gives a good result, keep it at 720 in that case or render at 1080, it all depends on what you want it for, it's better to render with "lower quality" if it takes to long time, in animation you can get away with many things without any one will notice it, but if you start to scale up it will just be ugly.

05-29-2015, 02:45 AM
Well then maybe i should try 1600x900. the end result is going to be used together with 1080p footage.

05-29-2015, 05:04 AM
Don't up scale unless you really really need to.

Ryan Roye
05-29-2015, 05:07 AM
For youtube videos, 1280x720 is a safe bet. Very few people will notice anything larger than that unless they are watching full screen mode; very uncommon for shorter works.

05-29-2015, 09:57 AM
I've been doing trade show work for years for my clients, and 720p is what I've been using. Most of their work is for Web or Trades at a good distance away. If it's a print piece for literature, I'll work for a size at 300 dpi.

05-29-2015, 10:53 PM
I recently needed to render something for a roll-up (those boxes you put on a floor and then pull out a banner type display out of them). The printer told me, he needs a 150 dpi (dots per inch) source image. The banner size was around 200 centimeter x 100 centimeter. So the math was:

200 cm / 2,54 = approx 79 inch
79 inch * 150 dpi = 11811 render size height

100 cm / 2,54 = approx 39 inch
39 inch * 150 dpi = approx 5905 render size width

I might have gone with a lower resolution but a roll-up is often used on a both where people watch it from a short distance. So I decided to go full res to get the best quality.

As a conclusion I would say the render resolution depends on the intended use of the image.

05-30-2015, 12:49 PM
Well then maybe i should try 1600x900. the end result is going to be used together with 1080p footage.

A lot depends on what size screen people are going to be viewing the video on and who is looking at it. Even on a reasonably small screen jumping resolution mid video seems very noticeable to me. On the other hand, unless I'm looking for it, I don't tend to notice something is done at 720 and not 1080, unless the screen is much larger then 40 inch. One thing that has worked for me is to play with the frame rate on the scenes that don't have fast movement. I saw some where that a lot of the early cartoons were shot at 12fps and then each frame was shot twice to film for the 24fps the projectors ran at. For a trade show video I did not long ago, I rendered out at 15 fps and then in the video editing program changed it to 30fps... cutting the render time in half. It was also at 720, since the screen in their booth was only 32 inch.

Really it all depends on the customer. If they want 4K at 60fps then that's what they get. Most of the people I work with just give me the 'just make it look good' :) Mostly it's just trade show and presentation stuff for people in manufacturing, so they aren't supper critical or highly focused on the video quality.

05-30-2015, 01:00 PM
It'll also depend on your resources. For an animated show it may not be practical to render 1080. It's more practical to render 720 and then uprez in Post.

05-30-2015, 01:21 PM
Scaling up isn't _that_ bad (depends on what it is used for and how much detail you have). Most of us have 1920x1080 monitors, and every time we look at a 1280x720 render in fullscreen, the graphicscard will upres it for us.

Quite some time ago I made a test with Octane... I rendered in 640x320, limited Octane to only spend 1 second / frame. I then took it into Premiere and upscaled it to 1280x720...

The result: https://www.youtube.com/watch?v=s3rUgHJmSI0

05-30-2015, 02:05 PM
you can render a stretched aspect ratio as well....

a lot of HD cameras will record 1280x1080 with a 1.5 pixel aspect ratio or (HDV spec 1440x1080 with a 1.333) and stretch it on display to show 1920x1080
DVCPRO HD spec is 960x720 for 720p and 1280x1080 for 1080p....every panasonic broadcast camera works this way

This would give you full vertical resolution with 50% less horizontal to render. Slower to render then a full resize but slightly better quality, hence why the camera manufacturers do it vs simply upscaling....

66% the render time of full 1920x1080

05-30-2015, 05:09 PM
For any application, both the device/medium and size/distance should be taken into account. The device is the initial factor, as to what it works best with, but the overriding factor is angular distance. IOW, what is the smallest detail that can be perceived at a given distance from the image? Taking things to extremes for ease of explanation, rendering for print output for a 30 foot wide billboard at 300DPI is WAY overkill. Eagles may be able to see detail that fine from 100 yards while flying past, but humans cannot. So, the resolution is wasted. We can readily see the difference between 720p and 1080p on a monitor, because we are within three feet of it. Place that monitor at fifteen feet, not so much. So, it depends upon what and where.

05-31-2015, 04:35 AM
For video I used to do a fair chunk of the 3D animations at 720p, but that has now changed as various production companies and agencies that I work with expect 1080p to be the miniumum standard now for their master copy, especially with 4K becoming more popular moving 1080p to 2nd place (where 720p was formally).

05-31-2015, 06:09 PM
For my own personal cg work, which tends to be 100% cg, I usually render at 720 and just keep it at that. Earlier this year, I designed and created a 2D animated cartoon for a film production. I did that project at 1080p but only because the 2D scenes rendered much more quickly than 3D.

For commercial 'film' vfx work at 1080p, we (myself and the places I've worked) almost always rendered 720p and bumped the renders up in compositing using the Lanczos method, which helps preserve fine detail when scaling up. This is partially to save render time but also because live action footage almost always looks soft by comparison to raw cg renders, and bumping it up will soften the cg to just the right amount for compositing. After you apply edge blurring, lightwraps, motion blur, and a little grain/video noise to the cg passes, the elements become more or less matched to the quality of the live plates. Final composited output should be 1080p, same as the live plate of course. Naturally, you'll want high quality AA settings if you're going to scale up.

If you really want to, there's nothing wrong with rendering your cg elements at 1080p but since you're probably going to have to soften it for compositing, IMO, it's a waste of time and resources.

Typically, the only time I ever feel I need to render 1080p or higher is when creating still elements for assembling a matte painting or for a long and mostly static shot, in which case I'm usually working with still images/paintings for composting anyway.

In the end, it really depends on how much you need or want to preserve the razor sharp quality so typical of raw cg renders. Most of the time, that super sharpness is not very helpful when trying to convincingly integrate it with live footage. For an audience used to looking at film, which tends to look much softer than video, extra crispy images are not especially pleasing to look at either.

Opinions and requirements may vary of course. The best thing to do is run some comparative tests and see for yourself what level of rendering you prefer or need for your production.


- - - Updated - - -

And when it all goes 4k, I don't think I'll have to patience to do it anymore. :)


05-31-2015, 07:43 PM
Our delivery method is the web but since we want to future proof all our work we render all at 1080p .
And all my virtual sets are done at 4k.

06-01-2015, 04:42 AM
Another option if you don't have the capacity for the higher res frames, is to render every other frame and use something like Twixtor in After Effects to fill the missing frames in. Can save a huge amount of time on a deadline.

06-01-2015, 08:01 AM
Do you have an example of this in action? I'd be interested in seeing the results.

06-01-2015, 12:01 PM
I did something like that in 'Happy Box' but only for the mouth shapes. If you recall, the mouths were very simple hand-drawn 2D elements rendered out of Lightwave and composited onto the 3D faces. By design, the mouths had a very limited number of shapes and meant to look a bit poppy.

At first, I thought this was the look I wanted but later I felt that maybe the sharp poppiness was a little too jarring for 3D. I didn't want to redo any of the animation so I tried the next best thing: blending. At first, I used Twixtor to basically 'morph' an fake in-between frame for the extremes. It sort of worked, that is, it took some of the edge off the poppiness while preserving the general style. In the end, I wound up dropping Twixtor and used simple frame blending instead. (I think it was Fusion's Timespeed node set to 0 with Blending set to 1.) Simple frame blending looked more consistent and was faster to render, and realistically you couldn't tell the difference (in this case) when played at speed.

As for the as the rest of that short, we did render everything on twos because we wanted HD but we didn't have an adequate render farm at the time, plus I had convinced myself that maybe, just maybe, it would make it look more 'stop motion' if we did it that way. (It didn't.) About a year after we finished the project, I tried smoothing the animation using Twixtor but, in this case, the result looked a little odd ('swimmy'?) to me so I left it alone. The test was academic anyway because I kinda liked the slight jerkiness. In fact, I remember at one point during production, we were tempted to drop it down to fours and make it super jerky.

Sorry, didn't mean to go completely off on a tangent but I thought some here might find this info interesting.


06-01-2015, 12:12 PM
Sorry for double posting. Connection issues.

06-01-2015, 01:46 PM
Another option if you don't have the capacity for the higher res frames, is to render every other frame and use something like Twixtor in After Effects to fill the missing frames in. Can save a huge amount of time on a deadline.

The interior footage of this was half the length when rendered out, but last minute the client asked if it could be slower. You get the odd glitch near the edge of the screen, but it was a small price to pay as it needed to be talked over. Excuse the awfully long fade to black at the end - think something went awry with YouTube's upload.


I have noticed that 'swimmy' look you mention, if I have a lot of stuff coming in and out of shot. It seems to prefer the slower moves, but then I don't know it intimately so it may behave better if I had more knowledge!