image resolution problems

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2handband

I'm exporting a file with images to a PDF, and when I do so it gives me a warning that the resolution on all the images is too low and on the PDF they're noticably pixelized. I haven't monkeyed with these images in any way, and  if I put them in, say, a Libreoffice document and export to PDF they come out fine. What gives?

pixeldust

Exporting a file from where? What is the dpi of the original images?

2handband

Quote from: pixeldust on March 13, 2011, 04:15:53 PM
Exporting a file from where? What is the dpi of the original images?

According to the warning message Scribus hits me with before exporting, one is 90X90, another is 96x96, and the other two are 72x72. I'm exporting to PDF from a scribus document.

pixeldust

Quote from: 2handband on March 13, 2011, 10:48:53 PM
Quote from: pixeldust on March 13, 2011, 04:15:53 PM
Exporting a file from where? What is the dpi of the original images?

According to the warning message Scribus hits me with before exporting, one is 90X90, another is 96x96, and the other two are 72x72. I'm exporting to PDF from a scribus document.

You are misunderstanding me - I wasn't asking for the dimensions, I was asking for the dpi - dots per inch. If you grabbed images off the web for instance they are going to be 72dpi. These are going to be pixelated in print format unless you scale them down by at least half their original size. For good print resolution you are going to need minimum 150dpi images, 300dpi is better.

To check your dpi open your properties window - it'll be under images.

2handband

Ummm... not good. The highest rate I have here are screenshots taken on my desktop... and they're only 96dpi. I've got to be able to use these pics... is there anything I can do?

Better question... how come the photos don't look pixelized if I export them to PDF using Libreoffice?

pixeldust

Quote from: 2handband on March 14, 2011, 02:40:26 PM
Ummm... not good. The highest rate I have here are screenshots taken on my desktop... and they're only 96dpi. I've got to be able to use these pics... is there anything I can do?

Better question... how come the photos don't look pixelized if I export them to PDF using Libreoffice?

96dpi is still better than 72dpi - as I said you could try scaling them down to look better. A better way but more involved would be resampling, in this case upsampling the image in Photoshop or other image editing software. This will make it look marginally better, at least to the human eye. Keep in mind though that upsampling the image only adds in extra pixels by averaging those around it - you are never going to get new detail into the image.

Don't know about the Libreoffice - I don't use it.

2handband

Quote from: pixeldust on March 14, 2011, 04:21:53 PM
Quote from: 2handband on March 14, 2011, 02:40:26 PM
Ummm... not good. The highest rate I have here are screenshots taken on my desktop... and they're only 96dpi. I've got to be able to use these pics... is there anything I can do?

Better question... how come the photos don't look pixelized if I export them to PDF using Libreoffice?

96dpi is still better than 72dpi - as I said you could try scaling them down to look better. A better way but more involved would be resampling, in this case upsampling the image in Photoshop or other image editing software. This will make it look marginally better, at least to the human eye. Keep in mind though that upsampling the image only adds in extra pixels by averaging those around it - you are never going to get new detail into the image.

Don't know about the Libreoffice - I don't use it.

Libreoffice is an example... same thing happens using Kword. The point is that using Scribus images get pixelized when I export them to PDF; I'm wondering why that doesn't happen with any other software.

pixeldust

#7
Quote from: 2handband on March 14, 2011, 08:02:27 PM
Libreoffice is an example... same thing happens using Kword. The point is that using Scribus images get pixelized when I export them to PDF; I'm wondering why that doesn't happen with any other software.

And I said I didn't know - perhaps they are upsampling the images automatically, the point is I have no idea.

What image editing software are you using? If you are using PS you can set the dpi to whatever you want before you past it to your artboard. You just can't do much with the photos you already have at 92dpi. You will have to do them again if you want a higher dpi. You can try fiddling around with the dpi within Scribus but I personally have no experience with it so I don't know what your results might me.

The BEST way IMO is to set a high dpi as you are capturing the image in the first with whatever capture software you are using.

2handband

Quote from: pixeldust on March 14, 2011, 08:15:17 PM
Quote from: 2handband on March 14, 2011, 08:02:27 PM
Libreoffice is an example... same thing happens using Kword. The point is that using Scribus images get pixelized when I export them to PDF; I'm wondering why that doesn't happen with any other software.

And I said I didn't know - perhaps they are upsampling the images automatically, the point is I have no idea.

What image editing software are you using? If you are using PS you can set the dpi to whatever you want before you past it to your artboard. You just can't do much with the photos you already have at 92dpi. You will have to do them again if you want a higher dpi. You can try fiddling around with the dpi within Scribus but I personally have no experience with it so I don't know what your results might me.

The BEST way IMO is to set a high dpi as you are capturing the image in the first with whatever capture software you are using.

Most of these image are unedited; what little editing I do is done using Gimp. I'll see waht i can figure out.

pixeldust

How are you getting the screen caps into Scribus? You must be using something I would think. Can you screen cap and paste directly in Scribus - is that what you're saying? maybe someone else will pop in who is more advanced - I'm not an advanced Scribus user either so I'm just giving ya what I got. 

2handband

Quote from: pixeldust on March 14, 2011, 09:08:40 PM
How are you getting the screen caps into Scribus? You must be using something I would think. Can you screen cap and paste directly in Scribus - is that what you're saying? maybe someone else will pop in who is more advanced - I'm not an advanced Scribus user either so I'm just giving ya what I got. 

Sorry for the delayed response. You save the screen cap, then create an image frame in scribus, right-click on the frame, select "Get Image", and navigate to it.

2handband

Actually, I've got it pretty much solved with the screen caps. I don't know what i'm going to do with the images i got from the internet, though...

Wena

I wanted an image of 300 DPI and by the info report in Scirbus 1.4 it had been reduced, is that correct. and how can I get it higher?
   
File: Starla_3 b.jpg
Original PPI: 300 x 300
Actual PPI: 177 x 177
Colorspace: RGB
Print: Enabled

I had set the DPI at 300 in Gimp 2.6

The printers; LS if I remember correctly asks for 300 DPI and not PPI, but I will have a look ans see just to make sure.

That 300DPI graphic that Scribus  but the results that I am showing is or has it changed?

But if it is supposed to be 300 PPI how do I so that?

Wena

Nermander

The DPI is not a property of the image file, it is a value calculated from the number of pixels and and printed size.

An image of 300x300 pixels printed at 1x1 inches will become 300 DPI, if you print the same image at 1.5x1.5 inches it will be 200 DPI.

Lou Siew Hei

About which dpi you need for printing, you can take a lot at this infomercial by Zebra Technologies on youtube, below is the name of the video.
'What DPI? Tips on Deciding Between 203, 300 or 600 DPI Print Resolution'
I can't copy the link, so you have to search for it, and all the dpi, pixel resolution related videos will show up too once you got to the video, hope this helps understanding about resolution.

And for the reason Scribus output looked pixelized, that's because the output was meant for the magazine, newspaper printing machines, ie industrial machines,  they had to be separated into films, 1 film for B&W, 4 films for CMYK, to be used on those machines; the word processor like softwares actually did not care about the quality of the graphics, they just take the graphics as they are, and leave the output pretty much to the printers connected to your computer.