Getting Professional Printing

[Nahee_Enterprises]

Aaron H. "ansr23" wrote:
>
>    the reason i generally don't go any larger is because i work with
>    multiple layers so any larger file size and i'll crash my current machine.
>    there's also the rendering time        ...................     are there any
>    file size limits for software like fractal explorer or ultrafractal?

One way or another, there will always be file size limitations, regardless of the software application used.  There are several factors that should be considered when rendering large images:

  1.   The CPU/s and it/their capabilities.
  2.   Available Hard Drive space.
  3.   Amount of RAM installed and usable.
  4.   Virtual Memory allocation.
  5.   Whether rendering from the application window or using a "Render To Disk" option.

By choosing the Render To Disk approach, an image can usually be generated to create a high-resolution image with better quality than is possible from the application's window.  Which means larger images beyond the capacity of your video adapter.

[bh]

Rarely does DPI ever translate into PPI (unless one is scanning, or digitally photographing, a printed image).  And then it does not mean much anyway.

Perhaps my question was not clear. I was speaking in terms of pixels per inch of paper, not per inch of screen. You seem to claim that we need as many pixels as we can print dots, but in my opinion it is not so useful.

[Nahee_Enterprises]

Bernard Helmstetter wrote:
>
>    I was speaking in terms of pixels per inch of paper,
>    not per inch of screen.  You seem to claim that we
>    need as many pixels as we can print dots, but in my
>    opinion it is not so useful.

Printed images never do have pixels, they use "dots" of colors.  To my knowledge, nobody refers to the "dots" on printed output (paper or otherwise) as PIXELS.  Which is why there is a difference in terminology:   DPI for printing   and   PPI for rendered images.  The term  DPI is often used interchangeably with PPI, causing a lot of confusion, however, DPI refers to the resolution of a printing device.  PPI is a measurement of image resolution that defines the size of an image.

There are several thousand web pages that can help in your understanding of these differences.  Try a quick search with Google, using the following two words:   DPI  PPI

By rendering an image with more pixels than you think you may need, it will give more flexibility in the printed output.  It will allow you to resize/resample the image if necessary to accomplish anti-aliasing, and to print with a finer DPI value for a higher quality of output, without getting a really small printed image.

[bh]

Printed images never do have pixels, they use "dots" of colors.  To my knowledge, nobody refers to the "dots" on printed output (paper or otherwise) as PIXELS.  Which is why there is a difference in terminology:   DPI for printing   and   PPI for rendered images.  The term  DPI is often used interchangeably with PPI, causing a lot of confusion, however, DPI refers to the resolution of a printing device.  PPI is a measurement of image resolution that defines the size of an image.

I know all of this! I have never called a dot a pixel. But obviously, values of dots come from values of pixels, and in average we have x pixels per dot. The question is: is it really necessary to have x=1 to get optimal printing results, or we can we do with less?

Next time I'm writing in chinese, we may understand ourselves better 

[lycium]

Printed images never do have pixels, they use "dots" of colors.  To my knowledge, nobody refers to the "dots" on printed output (paper or otherwise) as PIXELS.  Which is why there is a difference in terminology:   DPI for printing   and   PPI for rendered images.  The term  DPI is often used interchangeably with PPI, causing a lot of confusion, however, DPI refers to the resolution of a printing device.  PPI is a measurement of image resolution that defines the size of an image.

I know all of this! I have never called a dot a pixel.

easy now, not everyone on these forums makes the distinction and i don't think that was directed at you

edit: to answer your question, no, they are not directly comparable - for example the change of colour space, as you mentioned, makes a direct resolution comparison impossible. as a rule of thumb a dot pitch (as it's usually given) of .28 on a monitor looks reasonably smooth, and 300dpi on a printer (varies from printer to printer of course) looks good.

[ansr23]

 is it really necessary to have x=1 to get optimal printing results, or we can we do with less?

yes, but there needs to be a destinction between inkjet and commercial printing

commercial printing presses use halftone dots for shading, the level of detail is given as lines per inch (lpi)
inkjets however use colours for shading and randomly disperse the ink to get the overall desired colour (stochastic colour)

from what i've read, for inkjets, a file output of 1/3 the printer's resolution is recommended. so... 300 dpi = 100 ppi,
and 300ppi = 900dpi!!
if the file is larger that's fine, but it will only slow down printing, and may cause unwanted blurriness

[Nahee_Enterprises]

If the original rendering was 1600 x 1200, then printing at different DPI values would produce the following:

    DPI         Printed Image
-------------------------------------------
   100           16"  x 12"
   200            8"   x   6"
   300          5.3"  x   4"
   400            4"   x   3"
   600          2.6"  x   2"

Pixels per inch (PPI) or pixel density is a measurement of the resolution of a computer monitor's display, related to the size of the display in inches and the total number of pixels in the horizontal and vertical directions.  PPI may also be used to describe the resolution of an image scanner or digital camera; in this context, it is synonymous with samples per inch.

The measure of pixel density is useful for calibrating a monitor with a printer; software can use the PPI measurement to display a document at "actual size" on the screen.

The apparent PPI of a monitor depends upon the screen resolution (that is, number of pixels) in use; a monitor in 800 by 600 mode has a lower PPI than the same monitor at 1024 by 768 mode.

   http://www.michaelfurtman.com/pixels.htm

   http://www.tildefrugal.net/photo/dpi.php

   http://www.shortcourses.com/pixels/printed.htm

[David Makin]

thanks for your advice, i'll definitely consider final print size when rendering my next one.
are there any file size limits for software like fractal explorer or ultrafractal?

I don't know about Fractal Explorer but Ultrafractal has a "render to disk" option which effectively makes the possible render size unlimited - actually it makes it more subject to the file size limits of the system you're working on and even that's not that relevant since you can render direct to jpg.
Having said that however in UF there are still issues with rendering IFS or flames using the "normal" methods (or other fractals calculated in the "global" section - like some 3D fractals or strange attractors) which make the image size you can manage dependant on how much memory is available.

[Nahee_Enterprises]

Bernard Helmstetter wrote:
>
>    .....values of dots come from values of pixels, and in average we
>    have x pixels per dot.  The question is:  is it really necessary to have
>    x=1 to get optimal printing results, or we can we do with less?

You can do anything you choose to do, even if it is "with less".  And it is not "necessary to have x=1".  As they say, anything is possible.  But if you want QUALITY, then certain values should be followed.

A single pixel can be printed to paper and take up the space of 3-inches by 3-inches, though it may end up looking like an Andy Warhol image.  That same single pixel can be printed to paper and be just a portion of a single "dot" on the paper.  Pixels and Dots are not really comparable in the way you seem to be expressing.

You may be interested in reading this:
    http://aic.stanford.edu/sg/bpg/annual/v15/bp15-08.html


Bernard Helmstetter also wrote:
>
>    Next time I'm writing in chinese, we may understand ourselves better 

That is fine with me, I will have no problem, you may also choose any of the dialects that works best for you to communicate with.  I can also communicate in several other languages as well, if that better suits you.

[bh]

Bernard Helmstetter wrote:
> is it really necessary to have x=1 to get optimal printing results, or we can we do with less?

You can do anything you choose to do, even if it is "with less".  And it is not "necessary to have x=1".  As they say, anything is possible.  But if you want QUALITY, then certain values should be followed.

I've written about optimal printing results, so of course I want quality, even if I'm not screaming it. But I would also rather not send one of my 8000x8000 130MB PNG images on the internet if it's not necessary.

Pixels and Dots are not really comparable in the way you seem to be expressing.

You are the one who has repeatedly been claiming that we need as many pixels as dots. Did I miss something? When I write that there is less information in a dot than in a pixel, do you understand me? Do you agree?

You may be interested in reading this:
    http://aic.stanford.edu/sg/bpg/annual/v15/bp15-08.html

That's a good link. Thank to all who answered me btw, even if I'm still a bit lost.

Bernard Helmstetter also wrote:
>    Next time I'm writing in chinese, we may understand ourselves better 

That is fine with me, I will have no problem, you may also choose any of the dialects that works best for you to communicate with.  I can also communicate in several other languages as well, if that better suits you.

I could enjoy exercising my humble knowledge of chinese by discussing fractals with you, if you master the language; but you must have noticed the smiley. I had better choose easier topics.

[Nahee_Enterprises]

Bernard Helmstetter wrote:
>
>    You are the one who has repeatedly been claiming that we
>    need as many pixels as dots.   Did I miss something?

I do not believe I stated what you claim I said.  I have been saying that pixels and dots are different, and that the number of pixels will take up a certain amount of space on the printed paper based upon the printer's DPI setting.  It is nothing more than a simple formula to follow when one knows what size they wanted the image to be printed at and the DPI value.

>
>    When I write that there is less information in a dot than in
>    a pixel, do you understand me?   Do you agree?

Well that depends on the context of how each word is used.

Literally, there is no information in a printed DOT, it is just a splash of color on the paper.

And the PIXEL (the picture element) is very context sensitive when it comes to a definition and it's use.  When we talk about a graphic image format, it usually means the smallest complete sample of an image.  And that usually takes about three bytes of storage for a single color out of the number of distinct colors that can be represented.  But it could be as little as one byte of storage, or as much as six bytes of storage, depending on the number of bits per pixel (bpp).

But a single printed DOT could have been a combination of several PIXELS in the final output, and therefore required more bytes of data to make up that DOT.

[MattSchultz]

If you upload to DeviantArt, do so in JPG. While I agree that JPG is sacrilege, and PNG is better, the fine print on their site reveals that they actually convert your PNG to JPG on their end   . I'd rather have direct control of any compression going on, if there has to be compression at all.

[Fractal_Artist]

You can do better with an old DOS program called Fractint.  Version 18 or better allows you to edit the screen resolutions all the way up to 20,480 pixels squared.  You first have to get used to the DOS interface which is primarily keyboard driven.  The mouse is only used to create selection boxes that can then be used for in and out zooms, rotations, and skewed images.  You can also switch on or off the co-processor (aka FPU) which can result in longer computing cycles, but with seriously funky results.  At resolutions larger than what your video card supports the program also lets you work with billboard sized graphics by switching to a text mode rendering stage.  I cannot recall what it is called inside the program.  What is basically does is let your computer create marvelously huge fractals without ever seeing what it is you are actually working on.  And it does it all in just 640 KB of memory :0)

When I want to make a huge hunkin' fractal what I'll do is make a preivew size at a screen resolution like 1024 x 768 or 1280 x 1024.  Then working with that I will make all of my selections / tweaks and save my results.  Then I will re-load that same fractal and pressing the "Delete" key I can then scroll through to my ridiculous resolutions (using the arrow keys) and choose the video mode I want.  Once that new mode is entered you will see a screen of text showing what pixels are being computed and some form of ETA for the completion of your fractal.  Of all the fractal program I have and do use, I still prefer to use DOS Fractint.

Now, as far as printing goes, I am sold on the LightJets.  There is a company not too far away that I use to make my Limited Edition prints.  The cool thing is I get precisely back what I supply.  Pixel perfect results with zero ink used.  Instead a RGB laser is used to develop Fuji Crystal papers.  For a 16 x 20 I think I paid $18.00.  The image was flat and gorgeous.  I didn't have to worry about paper curl like I would if I had gone to a place like Wolf Camera to have the same fractal printed on one of their Epson inkjets.  The life span of the LightJet is estimated at around 100 years before fading can be seen by the naked eye.  That is the same life estimate I got when I used the local Wolf Camera / Epson print service.  I believe their LightJet has a 200 DPI output and can handle up to 10 feet wide by any length (or until they run out of paper).  Another service I am contemplating is www.wallmurals.com.  They have a minimum print size of 4 x 6 feet.  The samples that I got from them were most impressive.  You might also look into grand format printing.

I am lucky to have a friend with a gallery and frame shop and a big printer. She is enthusiastic about the idea of selling some of my fractals. My main problem is getting large enough images. Using Fractal Explorer's batch processing mode, I can go grocery shopping and come home to find either a 3600 to 4800 pixel wide image, or 50MB of corrupt mess, depending on the mood of my computer. No use trying for anything bigger, with what I have. I am aiming for a one to two foot size range in prints, for wall decor. At 300dpi, that's a lot of pixels

It is possible to enlarge them to a certain extent. I use IrfanView for that, because it works best with available computer resources. I must be patient, but it never gives me out-of-memory type errors, and always comes through.

So far I have found that making a very small enlargement - only about 50 pixels - using the B-spline resampling filter first, and then cranking it up all the way with the Lanczos filter, gives the best quality enlargement. The first incremental change serves to anti-alias all the hard edges. (Yes, I could do that when generating the image, but it would take three times as long, and the result would be no more certain. I might wait seven or eight hours for another failure rather than two or three.) IrfanView sets the DPI too. I save them in TIF format (best for my friend's Mac) and burn them onto a CD.

The enlarged images are not sharp at full size in the monitor, but when reduced to printed size they should appear as clear as the original unless viewed with a magnifying glass.

We're still in an experimental stage, nothing has been printed yet.