Making a Picture 600 DPI

[denise1]

Hi Everyone,

I am trying to make a picutre 600 dpi from a 300 DPI -- what do I need to do? I want to use the picture on my brochures. The picture was downloaded from a free photo site which I can use.

I was thinking I could print the picture in color then scan the picuture in at 600 dpi. Is this right? Is there an easier way? What are your thoughts?

Thank you all for your help.

[KDLA]

Well, it's awfully hard to increase the DPI and retain photo quality. You might take a look at this article: http://graphicssoft.about.com/cs/resolution/a/increasingres.htm

KDLA

[denise1]

I am not trying to increase the size of the photo just up the dpi. How would I do that? Is it possible? I need a 600 dpi photo for the brochure. Please advise. Thanks

[tracknut]

Resample the image in Photoshop, you'll get your 600 dpi and it'll be a lot better than scanning a 300dpi image at 600dpi. I presume that you've found a printer that is going to print the brochure at 600dpi?

Of course if you don't mind that the picture ends up 1/4 of the size, you could just set it to 600dpi and not do any resampling at all. But I'm assuming you want the physical print size to stay the same :)

Dave

[KDLA]

Oops - sorry - I sent the wrong article. :rolleyes:

KDLA

[denise1]

Thanks Tracknut!

Yes, your assumptions are correct. I was not sure how to go about this. Thank you

I will follow up!

[felgall]

To convert a 300dpi image to 600dpi you just need to halve the overall width and height. For example if it is a 4 inch by 6 inch image simply reduce the size to 2 inches by 3 inches without throwing away any of the image content and the dots per inch will be doubled. In photoshop you just do a resample specifying both the new size and the new dpi and those change will be recorded without actually changing any of the image content. The only affect that it will have is when the image is printed full size where it will thenn only appear at a quarter the size but with the extra resolution required.

[denise1]

Okay felgay.. Thanks

[Kor]

DPI and PPI are different things...When using Photoshop chose the proper term (DPI for printing quality, PPI for digital resolution).

[Mr.X]

for reference (dpi - dots per inch )
Try using photoshop or corel draw, cause if you scan the picture you'll definitely get a crappy quality. And that is for sure

[Poxicator]

The worse results will definitely be achieved by scanning your output, even if your output is print quality it will pick up the pattern of the printers and accentuate within your image. Scanning from a magazine would produce a pattern thats referred to as moire and its not easy to get rid of unless you suffer some blurring. I'm guessing your output is not up to print standards and therefore you're likely to pickup print lines across your image plus lots of artifacts incl banding.
Photoshop handles increasing images very well and there are alternative applications on the market that apparently improve on PS methods. The ones I've tried don't lead up to the hype. I've successfully increased images 600% without too much degradation using Bicubic interpolation but I've also found degradation at increasing an image 200%! I often work with images that reach 1gig in size and seldom work on images less than 30mb unless I'm dealing with web work, all these images are to a high standard and there lies the crux of the argument. If the original image is good quality (at least 20mb uncompressed rgb) you should be able to increase its size. However if your image is less than 1mb you'll no doubt lose image quality and experience ragged edges, pixelation and blurring. The nature of the image will also determine what can be achieved. If its an image of the sky/clouds you'll find it fares much better than an image with lots of detail.

You can successfully, without any loss of quality, amend your image size as described by felgall. Or in PS, IMAGE/IMAGE SIZE/ make sure constrain proportions is ticked, plus your resample method and change the Resolution to 600dpi.

I have to wonder however, why you require a 600dpi image. Image dpi is relative to lpi in print which relates to the screen process. Image dpi is required to be double that of lpi and often the lpi of print is 150, 165 or at artprint quality 200lpi therefore requiring a 400dpi image. I've been asked to supply 600dpi images myself but these have been for print on taxi sides, not for brochure work. If your dpi is higher than the required size for lpi it will be discarded during the repro process.