Sunday, March 28, 2010

Image Sizing

Okay - This is probably a simple question to answer. One that I have thought about for awhile. It applies to a project I have just started... So I thought this would be a great time to find out.



I am creating a large format piece. It is 96'' x 72'' at 150 dpi.



The printer I will send this to can print nicely even at 100 dpi.



After an extremely long grid and guide set up process (This piece has to look seamless - but will be broken up into many sizes) I brought my elements into the file. The photos I have are larger then I thought. So I wanted to raise the DPI to get the best quality I can. Before I bring the elements into the piece. (At this point the file is just a white background and many many guide lines)



So here is my question...

If I plug 50 more DPI into the piece making it now 200 dpi are the new photos and elements going to stay their true restraints without dithering or breaking?



Will the file read as if it was always 200 dpi when I start to import the photos or will it read as a 150 dpi and resize to 200 dpi?



So if the image sizing wont affect the file I would save much time not having to re-do what I have done.



Thank you very much
Image Sizing
%26gt;Will the file read as if it was always 200 dpi when I start to import the photos or will it read as a 150 dpi and resize to 200 dpi?



If you prefer to work at 200 ppi, since there is nothing meaningful in the file yet just resize to 200 ppi before you start to import pix.



%26gt;If I plug 50 more DPI into the piece making it now 200 dpi are the new photos and elements going to stay their true restraints without dithering or breaking?



I do not really understand that question. Note that you are using pixels not dots while working the file, so you are just establishing how many pixels in each inch. What is important is that all elements to be imported into the file come in at 200 ppi and the desired size of each incoming element is as measured at 200 ppi.
Image Sizing
Thank you.. You answered my question.



I just wanted to make sure the new photos would not be affected by the old PPI size.



I appreciate the response!

Also keep in mind that if whoever is outputting the file only needs 150ppi that extra 50ppi an inch will need to be discarded by the RIP or the Printer so you may be better off giving a file at the size that was specified. this way you can do the last minute sharpening.

I work in the art department of one of the biggest surf/skate companies in the world, and in 4 years I have never built a banner over 72 dpi. You don't mention what you are printing. Duratrans (lightbox image ? Digital print? Bus mesh? You are talking about an 8' piece.



In the case of your question, I would start over with a new document, and then add your photos. But your printer told you 100 would be fine. It will be.

Yes Steve's right, start with a new document. Resampling/changing pixel sizes is always destructive and should be avoided wherever possible. Especially when you are using resolutions as low as 100dpi



Want a way to non-destructively scale a document and know that the content isn't going to be altered in some way? set up the 'elements' you brought in as Smart Objects. Thats the only way.

Don't forget about ''Document Resolution'' vs. ''Image Resolution''. Your project sounds like a wrap or similar and will probably be printed via Inkjet. Most large format printers today are around 1440x720 ''DPI'' or, to be safe, 600 ''DPI'' ( dots per inch ). Your average 600dpi inkjet's screen frequency is around 72 ''LPI'' ( lines per inch ), but hardly an issue because inkjets print stochastically.



However, the screen frequency determines image resolution. So, based on 72 lpi, an average inkjet's image resolution would be 2x the screen frequency or 144ppi ( pixels per inch ). Whatever application you use to setup the final file, choose 600 dpi as the output resolution and 144ppi as the image resolution. I believe, if you import or place a 200ppi image, you shouldn't see any problems. But, if you import or place an image with 72ppi resolution, you may see some issues with blur or stair stepping, but nothing substantial.



That said, I don't think an additional 50ppi is going to make a dramatic difference and will ultimately be non-consequential.

Mark, that is a good point, your smart objects will retain their crispness, but that's just for your vector objects.



John, good information, but I would rather keep it as simple as it needs to be for Ron. In real world high output graphic environments, we don't need to worry about any of that. For a 8' x 6' document, 72 dpi is fine. Another good point to remember, is that your initial image still should be a good image to start with. Remember, what goes in is what comes out.

Steve, are you referring to image resolution @ 72ppi or document resolution at 72dpi? There's a difference and it is important.

John, I've never had to worry about the two. What's the difference and why does it matter?

Steve you need to read this if you don't know the difference.



http://www.adobeforums.com/webx/.3bb51427

John, Let's talk about what I need. I read that stuff in handouts when I was in graphics school 10 years ago, have been working in graphics even before that, and never needed to bother with it. You may sound smart reciting all that info, but on a daily basis doing real work, it doesn't matter. I am trying not to confuse Ron. In my office this month alone we've done over 30 print ads, (all different) and interior and exterior digital graphics for over 50 stores. I want to answer the question as straightforward as possible for him because it's actually quite simple. The printer knows what to expect and I know what to give him.

Well if you don't know the difference between dpi, ppi, lpi and you've never needed to bother with it before, why bother with it now. just blindly stumble on.

Steve,

%26gt; I read that stuff in handouts when I was in graphics school 10 years ago, have been working in graphics even before that, and never needed to bother with it.



As a design professional with a bit more experience than you, I'm just standing here shaking my head. All I'll say is at some time you will get burned in the wallet when an important job turns out wrong because you didn't understand, provide or follow the right specs.



Neil

Steve,

%26gt; I read that stuff in handouts when I was in graphics school 10 years ago, have been working in graphics even before that, and never needed to bother with it.



As a design professional with a bit more experience than you, I'm just standing here scratching my head. All I'll say is at some time you will get burned in the wallet when an important job turns out wrong because you didn't understand, provide or follow the right production specs. And that is a real concern for both you and your clients.



Neil

Buko, did you hear what I said? I've never in conversation about a job's output where I had to use the terms ppi, or lpi, and I'm hardly ''blindly stumbling on''. You're pretty demanding and insisting huh?



Neil, I gave myself away but saying 10 years. I see you're the all knowing guru scratching his head. I don't get ''burned at the wallet''. I don't have to piecemeal out my jobs to any old printer, give him a bunch of crazy directions and hope he prints the job well. I work with the best printers in the region. My budget is over 100 thousand dollars a year. Alot of people have more experience than me. So what. We're on the internet. I won't even argue who's more amazing. So what are your production specs that are so elaborate?



72 dpi RGB for large format digital graphics. 300 dpi CMYK for printed (magazines) materials. Again, to answer Ron's question, no, I wouldn't scale up a document with the images in it. I would start a new document or delete the images then resize up. If you need to. In his case he didn't. I have a 8 foot banner open on my desktop right now. 72 dpi RGB.

I'm not going to get involved in a petty bragging match.

I'm not going to get involved in a petty bragging match. You seem to know everything anyway.

Steve for someone who knows soooo much you don't have a clue.



Good luck!

%26gt;I have a 8 foot banner open on my desktop right now. 72 dpi RGB.



ppi.

What's the lowest ratio of dpi:ppi? What confuses me is how anyone could confuse the two. In conventional screening, doesn't an order of magnitude stand between the two numbers? The lowest multiplier I ever output to film was a solid dozen. Maybe a carpenter can weigh in on feet versus inches when cutting twice...



Steve: ''72 dpi RGB for large format digital graphics. 300 dpi CMYK for printed (magazines) materials.'' These numbers are for images. Got type? Any logos on that banner?



Be sure to read the link in post 10. And then start using these terms in conversation. B)



I print a lot of five foot banners and always appreciate that my vector objects get printed better than 72 ppi. Of course there's some additional risk, but the payoff has always seemed worth it.

Mark me down as another person here who used to design, scan for, assemble, send to RIP and print banners, billboards and wraps. The math, the distinct terminology and specific processes are important factors to be correct and accurate about.



So don't think your job is an esoteric one, Steve.

My job is esoteric? Hardly. Phosfourdots, ''The math, the distinct terminology and specific processes are important factors to be correct and accurate about.'' Umm, is there an argument about that? So what's this Jaloney? ''In conventional screening, doesn't an order of magnitude stand between the two numbers? The lowest multiplier I ever output to film was a solid dozen. Maybe a carpenter can weigh in on feet versus inches when cutting twice...'' WTF? It's funny how you all are telling me what I have to do, and I'm telling you what I do, and you say I don't have a clue. J Maloney is telling me how I should converse. I understand when I create a Photoshop document the dialogue box says ppi. I never hear anybody describe a document as ppi. They say dpi. I don't care if you think it matches your scientific standards. That's just how it is. To us, where I'm sitting, sure I have vector images in my large format graphics. They come out fine at 72. When I go down in size, for instance for a small lightbox image, I will increase the file to 150. Buko, can [obscenity deleted].

Folks, it is apparent that attempts at enlightenment are neither appreciated nor will they change a thing.



Let's just call it a day...



Neil

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