Hi! I would like to render an scene in Vue 5 with an 4000 x 4000 pixels @ 300 dpi... but when i opened it in photoshop it says that the resolution is 4000 x 4000 pixels and only 72 dpi (default). It doesn't matter if i change it into 150 or 600 dpi it always stays 72 dpi. I render to disk.. Does anyone knows what i am doing wrong? TIA Ronald

The dpi parameter has no sense if you render in pixels... a 40004000 pixels picture is allways a 40004000 pixels pictures... The dpi parameter has sense if you render in inch or cm width and height ... dpi = dot per inch :-)

okay i see,

but what if i would like in poser render an image with a resolution of 4000x4000 pixels @ 300dpi. You can do that in poser btw. Poser calculates what the corrects values (i guess) and gives me an (large) image with resolution 4000x4000 @ 300dpi.

How do i calculate this for vue 5?

TIA

Message edited on: 03/31/2005 14:59

Select the width and height you need in inch or cm ... the size you want to be printed on paper for example... then select the dpi ...Vue will calculate the width and height in pixels.... take care that your printer can print in such a resolution to obtain the right size ... For example, when you want to publish a picture, the professional standard is mostly 300 dpi ( this is a printing standard, not an 'on screen' standard ) ..... You only have to choose the width and height in cm or inch ... and the dpi. I don't really understand what you mean with Poser ...

Then what you really need to calculate is the dimensions of your pictures at 300dpi. If you want to make a picture with the dimensions : 8 inches by 5 inches, using 300dpi, you need to render a picture with the dimensions : 2400x1500 pixels (8300 and 5300). Vue allows you to enter the dimensions directly in inches to save you from calculation that by yourself. I don't understand why Poser allows 4000x4000 @300 dpi... this is meaningless.

This is a common misconception. There is no difference in screen fidleity between a 72 dpi 4000 x 4000 image and a 300 dip 4000 v 4000 images. The dpi is just for printing purposes. A 4000 x 4000 at 72 dpi image would equate to a printing size of 55.5" x 55.5". A 4000 x 4000 image at 300 dpi would print at 13.33" x 13.33". Just figure out what size you're going to need and for what purpose. For high quality magazine work, 300 dpi is the standard. So if you needed a 5" x 5" picture, you would need a graphics render resolution of 1500 pixels x 1500 pixels.

Maybe someone should mention simply what "dpi" means. Dots Per Inch. So if you have a fixed number of dots (pixels) the dpi value only tells you how big the image is. Nothing else.

Well, now I'm getting confused. In the above example, "needed a 5" x 5" picture, you would need a graphics render resolution of 1500 pixels x 1500 pixels", the graphic would STILL need to specify how many pixels were packed into an inch. Because if, for example, you had an image 1500 x 1500 pixels in size (with an additional specification of 100 DPI), the printed size would be 15 inches by 15 inches. So, if I am in Photoshop (with this image) and I want this image to print out at 5 inches by 5 inches, I need to alter the image dimensions. And anytime image dimensions are altered, the dots are altered with an algorithm. An algorithm that isn't perfect (and therefore adds a bit of distortion). Am I wrong?

What i did once is to go to Photoshop and created an image 12 inch long and one inch wide (if you need that). Could be 1x1 centimeter as well for the Europeans. Both with lets say 300 DPI - the standard resolution for print issues. Then under image size i checked how many pixels there are now on this inch or centimeter. Ok, if i want now a 5x5" image i can multiply the amount of pixels per inch i know now by 5 and get the pixels i need to render. Wether Vue says 72 dpi or 300 does not matter, i can change that in Photoshop easily to the value i need. And i have to go to Photoshop normally anyway to change the color mode for print issues. CMYK instead of RGB.

Well, let's see if I can say it a different way: Looking in Photoshop, an image... (1) 3000 x 3000 pixels and 300 DPI will print an image 10 inches by 10 inches. (2) 3000 x 3000 pixels and 72 DPI will print an image 41.667 inches by 41.667 inches. (and "we" don't want that so...) ...we come to (3) Change image #2 described above to make it print out a 10 x 10 inch image by coding 300 DPI in the resolution and restoring our original values to 3000 x 3000 (from 12500) the original pixel size. My contention is this: Printing (1) above will result in a less-distorted image that printing (3) (the one that underwent size adjustment and algorithm computation). And IF my contention is correct, then there IS a slight benefit to having an image created at the pixel size one needs instead of having to adjust it later. Of course, I could just be wrong (LOL).

When i know i need 3000 x 3000 pixels (whatever inch size that means is another problem) and render them there is no adjustment in terms of recalculation. Full stop. Just a change of dpi values to correct the inch size. The pixels stay untouched and the same. The only adjustment you have to do always is the change to CMYK to go to print. And this can be a BIG surprise. Try a full green in RGB and switch to CMYK. Fun!!!

LOL...never changed to CYMK yet (but I never printed anything to a professional printer...just my inkjets which, as I understand it, are "tuned" to RGB profile anyway).

They do the change internally. Thats why your prints look so strange sometimes - sorry, couldn't resist. Even inkjets are based on CMYK - look simply what ink colors are in there. The problem is that different color models have different capabilities - and no-no-s. Bright green (pure green) is one of these. Good in RGB, impossible in CMYK. I prefer to see the result beforehand in Photoshop, gives relatively good previews of CMYK images. Relatively good.

I'll have to do some investigating and see how things turn out. I need to profile my display, scanner, and new Canon i9900 sometime, too.

I HATE THAT. Good that my corporate customers have defined color settings so that i don't have to worry too much most of the time. For the rest i check things in Photoshop. That is calibrated to our printer (company) so that i know how things come out when i send them to print (more or less). Too bad, no calibration for content!

When "resizing" in Photoshop just uncheck "resample image". No change to the actual image (the pixels) will then occur, it will only set the DPI flag to your specified value. - Oshyan