Photos in PDF's

[Cormac]

I hope that I am posting this to the right forum.

Would pictures in a PDF of a higher or lower quality than the same pictures scanned as image files?😕

 

[efxgraphx]

I hope that I am posting this to the right forum.

Would pictures in a PDF of a higher or lower quality than the same pictures scanned as image files?😕

Not sure if I understand what your asking. If its a quality issue, it may depend on your setting in Acrobat when you made the PDF compared to the scanned image. You may need to elaborate a bit for me to get a better understanding of your comparison.

 

[SwiftLives]

It depends on the resolution in which you scan your pictures as well as the resolution settings used to create the PDF.

If you're planning to print the PDF, 300dpi is optimal. The tradeoff is the filesize can get very large.

If you're planning to post it to a website or simply email it around, then 72dpi is plenty.

 

[Cormac]

You may need to elaborate a bit for me to get a better understanding of your comparison.

Sorry for the delay and the lack of upfront info.

Here is I know. A someone I know wrote a book about family history and gave me a PDF copy of the book. In the book, this person include some old photos that I presume were scanned in. I believe that quality of the pictures that I "capture" from the PDF will lower than if I were to work with scanned copies of the original photos. Am I close to being right?

 

[decksnap]

The answer is most likely yes. The PDF itself might not have been cooked at 300 dpi print quality, and whatever method you are using to capture the images from the pdf might reduce the quality as well. If the sources are in good shape, the sky's the limit on quality if you are scanning them yourself. Unless there was a lot of touch-up work done in the process of creating the book that you would have to recreate.

 

[MisterMe]

Sorry for the delay and the lack of upfront info.

Here is I know. A someone I know wrote a book about family history and gave me a PDF copy of the book. In the book, this person include some old photos that I presume were scanned in. I believe that quality of the pictures that I "capture" from the PDF will lower than if I were to work with scanned copies of the original photos. Am I close to being right?

There are only two ways to get a photograph into a computer. You take the photograph with a digital camera or you scan a chemical photograph on paper. Photographs even at book or magazine resolution consume a massive number of bits. Distiller and other PDF creation utilities have settings to compress raster images [and reduce their resolution] to keep graphic-intensive PDFs to a manageable size.

Additional information: PDF is a poor format for raster images. PDF is a proper subset of PostScript in pure ASCII text. Raster images are best handled with binary formats.

 

[efxgraphx]

Sorry for the delay and the lack of upfront info.

Here is I know. A someone I know wrote a book about family history and gave me a PDF copy of the book. In the book, this person include some old photos that I presume were scanned in. I believe that quality of the pictures that I "capture" from the PDF will lower than if I were to work with scanned copies of the original photos. Am I close to being right?

You are correct (to an extent). You can read MisterMe's post above for the details. I will let you know that I have used PDF images before when it was the last resort (Obviously the PDF was saved for print resolution). I just opened the PDF in Photoshop and cropped out the images I needed.

Also, keep in mind some printers I use are requesting PDF files to print from rather then the native files.

Hope this helps.

 

[dcr]

Additional information: PDF is a poor format for raster images. PDF is a proper subset of PostScript in pure ASCII text. Raster images are best handled with binary formats.

Not true. PDF's imaging model is based on PostScript but PDF itself is not a subset of PS, nor is it ASCII -- it's a binary format.

http://en.wikipedia.org/wiki/PDF

Images inside PDF are basically binary blobs (compressed using a variety of lossy or lossless filters). While PDF is not an ideal format for editing or interoperability with other imaging tools, there is little overhead in storing images themselves in PDF format.

 

[covisio]

I don't know how you're extracting your images from the PDF, but a cool and fast way is to open up the PDF in Photoshop, but in the import window select 'Images' rather than 'Pages'. This will then allow you to choose the specific image you want from the document.
The only downside of this method is that if the PDF was flattened on output (i.e. saved to PDF 1.3 or below), then your images may be chopped up into bits, depending on how it was constructed.

PDF is a poor format for raster images

How else are you supposed to create a portable, viewable and proofable document that contains both vector and raster images such as that created when a book or magazine is put together (and don't say PostScript!)?
Virtually all modern print workflows are based around PDF. It has been capable of providing accurate, print ready files of any quality required and any print process for many years. So long as the person who makes the PDF knows what they're doing.