[martgreg]

I am trying to figure out what size is best to render...

i aslo remember a thread kind of concerning this but your input would be greatly appreciated !! experiences and hints

I know there are many variable but i predict that most of the work I produce will be web based and therefore not have to be super huge...

But what abut printing on paper

EG if I want a 300 dpi image for 8 .5 by 11 = 3300 2550 pixels

Is this right .. is there any reason to go larger...

is there a limit that a "typical" print shop can handle.


Thanks

[JCAddy]

6300x4500 is what we normally render at

That will give you a 30"x42" board at 150DPI.

[martgreg]

Ok cool .....

so would that give me 300 dpi at 3150 by 2250

i am trying to get my old brain around this stuff ?

[mashium123]

Hmm... let me put it this way.

As a rule of thumb, they say:
(please don't ask me where I got that from , I don't remember, but it works good for me..)

8400 : distance to the pic in cm = (minimum) needed Pixel per Inch

That would make Hyperballad's pictures look good, when you keep a minimum distance to them of about 56cm, which is about 22 inches, which one could call quite close considering the size of his prints, imo.

Btw: 1 inch = about 2.54 cm

Hope, it helps.

[Bubbaloo]

One thing I can say that doesn't have anything to do with dpi or viewing distance is, I always render at the largest resolution within reason and then downsize to whatever size I need. In Maxwell, the larger the render, the more detail/less noise you will have. It has to do with the ratio of noisy/clean pixels. That's been my experience anyway.

[martgreg]

mashium : sorry I dont really understand what you mean ??

for example if you were printing a 11" by 17 " inch .. what resolution would you print can you explain your system ..

thanks

Bubbaloo

That soumds teh most ideal to make as big as time will allow ..

and when you down size for print would you you do it in Photoshop and does this cause any loss in quality ..

currently I just place in illustrator and resize it by dragging it ?

i wonder if this is a bad way to do it ...


Thanks

[ivox3]

martgreg ......

This stuff isn't as confusing as you think, ... people make it confusing.

There is no DPI law.

When you have a project that you know is going to be for print, ...first thing you do is to determine what type of imagery is going to be rendered/printed and then what will be the final size of the printing.

In theory, ...its obvious that the more pixels you have in an image, ..the smoother the edges will be, the better resolution of fine details and generally, ... a better print. But having any size is obviously not realisitic and besides, ... unlike in photography, there simply isn't as much detail to be seen in most renders (eg., diffuse presentation renders). So, the main reason for having a large resolution is basically for avoiding pixelation or un-smooth edges(aliasing).

So, .. I'd ask, .... what's the subject matter and intended audience of your project? Ad for a car shot, diffuse presentation image? generic interior/exterior? product or jewlery shot?

Personally speaking:

Producing images for presentations(mine) or to simply convey ideas I usually cheap out anywhere from 96 -150 dpi. These will be printed anywhere from letter size to A3+(13 x 19). Keep in mind the nature of these images, ... these are akin to what the pencil used to do -- idea sketches.

Now, .... If the project goes a bit further and needs more clarification, more meetings etc.. Then I'm in the 150-200 dpi range for the same size paper as mentioned above. These have more detailing added in the modeling/texturing level, so the bump in dpi is needed to define that better. To the non-discriminating eye, ... these renders look damn good in print.

Lastly, ... I personally reserve the 200-300 dpi range for printed portfolio pieces and professional projects with dpi requirements.

Summarizing now, .... I'll repeat by saying that, 'there is no law concerning dpi', there's only the quality of how an image looks in the end. Sometimes a project will call for 300 dpi, .. so you'll have no choice in the matter, but most stuff is for Us, ..so you can exercise a greater flexibility.

My best advice is to run physical tests to see for yourself the differences between printing something at 96, 150, 200 and 300 dpi. Seeing is believing, .. .so its good to know at what threshold dpi will make for a significant difference ... this way you can accurately determine the initial size of the render from the onset.

** Its true about rendering large and then scaling down helps the noise ratio ------- see here for a proper way to downsample large renders.

http://www.imagecommunications.de/tutor ... in_ps.html

ps. I'm in the process of revising my thread on DPI in the tutorial section to be simpler and more succint ----- it'll be added to the Think site --- soon. Look for it...

[mashium123]

mashium : sorry I dont really understand what you mean ??

for example if you were printing a 11" by 17 " inch .. what resolution would you print can you explain your system ..

thanks
...

Sorry martgreg,
it' s the language barrier I ran against, I guess. I'll try to be more clear, considering the provided data.

But generally I'm with ivox3 here.
The "system" is just a rule of thumb, that tells you that you have to decide yourself, when a print "looks good". There are factors, that have an influence on that decision, as ivox3 mentions.
The only factor, the above "system" takes care of, is the distance of the observer (you) to the printed picture. It's obvious that a picture, that is printed on a sheet of paper, does not need to be printed in an high resolution (many pixels on one inch), if you're going to look at it from a distance of 20 meters...

So, back to the data you provided:

The "systems" question again: would you want to look at this print from a distance of one inch, right in front of you nose, or will you keep it away a bit to have a "good" look at it? As an example I'll keep a distance of 50cm. That's about 20". (But that's really your decision in the end).

wished print size: 11inch (~28cm) * 17inch (~43cm)
distance: 50cm (~20inch)

8400 : distance to the print (in cm) = (minimum) needed pixel per inch
-> 8400 : 50 = ppi -> 168 = ppi
That would need you to render a size of:
x=168*11=1848
y=168*17=2856

So if you want to print s.th. at given size, you'll need to render it out in 1848 * 2856. At a view distance of 50 cm you will see a nice print. If you get closer though, you will start to see a pixels... because that print was made for a view distance of minimum 50cm.

At least, these are my experiences...

[lebbeus]

just curious: what does the 8400 value represent? is it 8400ppi.cm?

[mashium123]

lebbeus,
I have no idea.
I even don't remember where I got that from.
I noticed it long time ago, wrote it down and had a lot of tries since then.
Mostly archviz though.
And I've made positive experiences with it in my cases, that's why I wanted to share...

Definitely you could take ~3300 instead of 8400, if you want to provide the distance in inch and not in cm.

So that would be

3300 : distance to the print in INCH =ppi

(because 8400:2,54 is = about 3300)

Note that this is a rule of thumb... it's not about 5 pixels more or 5 pixels less... it's a round-about thingy... a good orientation, at least for me...

[deadalvs]

maybe helpful...

http://www.maxwellrender.com/forum/view ... hp?t=22985
http://www.klausbusse.de/mxc/

[martgreg]

Thanks guys that helped alot ...

I will conduct some tests based on teh info you guys gave me and I will take it from tehre

Thanks a million