300dpi

[sherridge101]

Hi all

We can change the dpi from 72 dpi to 300dpi in photoshop, but is there a way, or a script for setting this in VRay for Maya?

Cheers

[Neilg]

what are you trying to achieve by changing the dpi of a raw render? do you print unedited images to an exact mm accuracy scale straight from windows explorer?

[sherridge101]

We set all our images to 300dpi for print, so wanted to set this in Maya.
Just trying to cut out the photoshop step - we could have a Render Settings profile, or master file set to 300dpi, cutting out the Photoshop step on thousands of images.

[SonyBoy]

There is no such thing as DPI straight out of a CG renderer, only X-Y resolution. DPI stands for dots per inch, which implies a fixed image size and is a print specification only. The correct resolution is determined simply by the size you want to print at, multiplied by the number of dots (pixels) you want each square inch to have. So, an image that you want to print at 8 x 10" @ 300 DPI would be 2,400 x 3,000 pixels. But an image printed at 16 x 20" @ 150 DPI would be the same.

[SonyBoy]

Also, if you do have to change your DPI on a lot of images, you can make a Photoshop action which you can run on a whole folder.

[Neilg]

cutting out the Photoshop step on thousands of images.

So what do you use to print them? and what are they for?
there's a pretty good chance that changing the dpi in photoshop isnt actually doing anything. it's a meaningless concept, sonyboy covered it.

[sherridge101]

The images are printed at 300 dpi in brochures etc.
We're just looking at setting this once, earlier in the chain.

There's an old mel script on highend3d, but I can't get to work in Maya2018.

[Undersky]

So what do you use to print them? and what are they for?
there's a pretty good chance that changing the dpi in photoshop isnt actually doing anything. it's a meaningless concept, sonyboy covered it.

It's not meaningless. I regulary save tifs straight out from the renderer (simple arch-viz volumes that doesn't really have to look all that pretty) that the architects wants to put in a printed presentation or print directly to draw on. And a default image is saved with 72 DPI. By using the 3ds Max print wizard to quickly set correct resolution (based on dpi), and then saving as a tif, the DPI is set to what I want, and I don't have to go through Photoshop just to change the DPI. Or I can just set it in the tif saving dialogue.

Sherridge101: I don't think there's an automatic solution I'm afraid. This is what Autodesk say about it in the help files (although the entry is from 2009, things could have changed).
https://knowledge.autodesk.com/suppo...otoshop-s.html

[sherridge101]

Cool, cheers for the link.
I'll ask on the Autodesk forums too.

[crazy homeless guy]

What format are you using out of Max? You can set the DPI on tiff output. In fact I think it is 300 DPI by default.

If you are trying to create a button tight workflow and aren't using TIFF I would venture that setting your file to 300 DPI can also be accomplished by using a post render script and Imagemagick.

Now here is the thing. DPI absolutely does not exist in digital files. It is impossible. Most confuse PPI and DPI. PPI is pixels per inch, DPI is dots per inch. DPI represents the density of ink that the physical printer is capable of, or will replicate. You can have a 72 PPI file and the printer will still output it at 300 DPI the only thing is you will see the 72 pixels in that inch, but trust me.. it is still 300 DPI.

[sherridge101]

Cool, cheers.

I'm using Maya. Are there similar options?

[crazy homeless guy]

Ahh... Max... Sorry.

But back to Imagemagick... You could make a drag and drop batch file that converts them in a few seconds wihtout opening anything, or if you have a little code hacking knowledge you could write a post render script for Maya that automatically does it for you.

http://www.imagemagick.org/discourse...ic.php?t=18241

[Undersky]

Now here is the thing. DPI absolutely does not exist in digital files. It is impossible. Most confuse PPI and DPI. PPI is pixels per inch, DPI is dots per inch. DPI represents the density of ink that the physical printer is capable of, or will replicate. You can have a 72 PPI file and the printer will still output it at 300 DPI the only thing is you will see the 72 pixels in that inch, but trust me.. it is still 300 DPI.

Yeah, but the thing here is if you set your DPI, then your customer (or in my case, collegues) can just go ahead and print it and it will be correct size for them. Or they can place it in InDesign, and it will come in with correct size. Not all of us are working 100% digital =)

Oh, and yes, DPI exist in digital files as meta data (in the format that supports it) to tell the printer how big the file will be when printed. PPI, on the other hand, is a "dynamic" value, and will differ depending on what size of screen (and resolution) you're viewing the image on.

[sherridge101]

Thanks all.

I've gone for a droplet in the end. I know there's a small wait for the files to open, change res and save down, but this avoids having to install ImageMagick etc. on all our machines.

Thanks again.

[crazy homeless guy]

Deleted message.