Rendered files at 300 dpi

Hi to you all from a new Blender user, firstly thanks to all those who have created the program and dedicated all your time and effort. Its while early days yet, 30 days to be exact, after reading/working through the documentation which l must say is very informative, l am beginning to figure out how to turn ideas into reality, or not as the case maybe. But enough to say it will be some time before l enter the “speed modelling contest” :smiley:

Briefly, l am a photographer at heart learning to merge 3D with photography, l am not to much of a stranger to 3D as l trained some years ago on 2D/3D and 3D studio with AutoCad, dare l mention their name here, but there you have it

Anyway, you guessed it l have a question:

I am used to working with 300 dpi images from source (i.e. out the back of the digital / scanned files from film). Once l have rendered something in blender l seem only to be able to save the rendered image file (tif works for me) at 150 dpi, am l missing something/lost the plot ? Is there a command line option l can use, or a plug-in available so l can save rendered images directly/automatically at 300 dpi?

Appreciate any help / feedback

Best regards from Switzerland


As I understand it Blender renders to an image resolution x pixels by y pixels.
dpi is a print term. Your image editor gives dpi data as a printed image size, which isn’t the same thing.

If you need to print the image at a certain size at a certain dpi you only need do some arithmetic with the render resolution.

An image 300 x 300 px is a different physical size at different print resolutions, but retains the same pixel resolution.

Probably 150 dpi is the image editor default.

I don’t think it’s possible to do this sadly. However, you can enter the image size you want manually, and then edit it to be 300 dpi.

If you want it to be letter size,.then it would be 3300 x 2550 pixels. If you are using photoshop, you do this by going to the “image” menu, then “image size”, disable the “resample image” check box. Then in resolution change the existing number to 300. When you are done just click ok. Just remember to check the “resample image” box for the next time you want to change an image size by pixels.

By the way, I just checked and in my computer blender renders all the images at screen depth (72).

DPI doesn’t mean anything in this context. Pixels are pixels.

A 72 DPI image is no different than a 300 DPI image. The pixel resolution is whatever you want it to be.

From the little I’ve found out about this, you do indeed need to do some math.

To get the resolution you want, each pixel needs to be one of those dots-per-inch, so you need to convert your paper size to horizontal and vertical pixels.

For A3:

11.7" by 16.5"
11.7300 = 3510
300 = 4950

So allowing for no margin, to render an image at 300dpi at A3 size, your render would need to be 3510 by 4950 pixels.

sorry, but this statement in’t true, nor does it help the original poster…

most image formats store a dpi setting, so it’s not “meaningless” . This allows the print size to be set with the document…

The pixel resolution is whatever’s set in the file…luckily, most imaging software allows you to manipulate this (and easily) … except blender it seems…which is what the OP was asking!

My bet would be that Blender doesn’t even set it, so it would be whatever is the default for that particular file format or editor.


in the scripts pack
there’s a dpi calculator that looks like it works properly.
hope it helps.

Many thanks to all for your feedback most helpful.

Best regards,