The great render resolution debate.

There is a lot of debate on ‘render resolution size’, so I thought I’d reign in and let you know what resolutions we use at Burn.

The greatest render size myth of all being DPI.

DPI (Dots per inch) refers to printer/scanner hardware resolution. If a printer prints at 300 DPI then it prints 300 dots horizontally and 300 dots vertically over a square inch of print media. Therefore, having a printer that can print at a higher DPI means that the quality of the print will be, to some degree, better.  That being said, this has absolutely nothing to do with render resolution. DPI shouldn’t factor into your render resolution because it is print terminology, not a digital measurement of quality.

Computer/TV screens display their output (screen resolution) in pixels or tiny dots of colour that make up the image. We should be referring to render size we need only concern ourselves with the “screen-resolution”, which is Pixels in the width of the image and pixels in the height of the image or HxW.

Baring this in mind, the higher the number of pixels, the better the print quality will be when printed at larger sizes. Remember that when you enlarge/re-size an image, the photo editing software guesses and makes up the pixels areas of the enlarged image, so avoid rendering low and the up sizing. Clearly the more points of information that create the image, the more detail that can be represented when the image is ultimately printed or displayed. So there is a correlation between render resolution and print quality, but this should be expressed screen resolution and not Dots Per Inch.

We need to understand the minimum amount of pixels required to display an image on screen and then ensure that it translates correctly when printed at varies sizes. In the 3D world, you will play a constant game of render time vs render resolution. It would be fantastic to provide prelim renderings at 3500px, but this is impractical.

Here are the render sizes (screen resolution) that we generally use and where they are best suited:

Preliminary Renderings:

For prelim renderings (during our approval period) we do 1024px renderings, either grey scale or in colour and always with anti aliasing on.
If the client has an internal review or needs to show another party before we finalise the project, we then render at 1600px – this should print adequately at A3.

Its important to render at this low resolution often – if the file is to heavy and crashes at 1024px its never going to be production ready. Internal reviews can be done at half this size, 512px is perfect for a quick render check.

Final Renderings – for A2/A1 prints

To print at A1 – we generally render between 2500px and 3500px – This always looks good at A2/A1 print resolution.
This should be more than adequate for Magazine and book prints – although some editors demand images at 300 DPI (Because they don’t understand image resolution).

Don’t be fooled, you do not have to render images at 6000px to print at A1 – we have our own Large format poster printer, so this size allowance comes from personal experience and 1000’s of prints.

The file size is also manageable , these uncompressed JPEGS shouldn’t be larger than 6 – 8 megs, which is perfect to email.

If your client intends on printing this image larger than A1 – you should discuss this before hand so that you can facor this into your price and time allowance. Larger renders, take more time and consume more resources.

Final Renderings – for A0 prints

To print at A0 – we generally render between 4000px and 5500px – This always looks good at A0 print resolution at full colour space.

Billboard

We have done many billboard renders at 9000px-12000px – Larger than this will NOT be noticeable on a billboard, if you don’t believe me – get up close to a billboard image and observe how far apart the printed dots are. There is a point when jamming in more pixels won’t make any difference for a media that is meant to be viewed from 10/50 meters away.

More Resources:

There is a fantastic write up about this here: http://www.dpiphoto.eu/dpi.htm

Comments - No registration needed