Editing Image in Preview

ghsNick

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May 25, 2010
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Hi -

We're editing a photo I took on my drone to hang as wall art. The frame is 36x24 and I'm editing down the size of the image since it was a huge 4K picture that wasn't in the right aspect ratio.

I edited the image to the exact size of the frame but now I'm wondering how I keep the same Hi-Res image quality...when I edit it shows 72 DPI as the default...Can I (Should I) increase it to 100?

Any advice will help! Thanks
 

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ghsNick

macrumors 68030
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May 25, 2010
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Does anyone have some advice on this? Trying to get this printed and don't know what to do for DPI?
 

BrianBaughn

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You should pick at least the DPI of the printer that will be used. But...whatever printer you use will probably just convert a higher dpi down to the resolution it prints.

100dpi isn't very fine resolution. What is the resolution of the original?
 

ghsNick

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May 25, 2010
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You should pick at least the DPI of the printer that will be used. But...whatever printer you use will probably just convert a higher dpi down to the resolution it prints.

100dpi isn't very fine resolution. What is the resolution of the original?
Thanks! How do I figure out the original?

Check printer dpi,set photo resolution to the same,on most home printers it's 300 dpi.
Thank you very much!
 

ghsNick

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May 25, 2010
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In Preview, Tools>Show Inspector.
The original resolution is 72 DPI but I want to print this out as wall art for my house...can I make it 300 DPI so it looks good when printed?

Or is it too late since the original digital file was 72DPI?

Thanks
 

BrianBaughn

macrumors 603
Feb 13, 2011
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Baltimore, Maryland
The original resolution is 72 DPI but I want to print this out as wall art for my house...can I make it 300 DPI so it looks good when printed?

Or is it too late since the original digital file was 72DPI?

Thanks
Yes...the simple thing to do would be convert to higher DPI and then reduce to the print size.

But someone else may have specific tips to keep the image as sharp as possible.
 
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robgendreau

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Jul 13, 2008
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OK, that 72 DPI means nothing until you send it to a printer. It's kind of a placemarker, and has no effect on viewing it digitally on your screen. You could use any DPI you want depending of course on the possible resoluton of your printer.

Do some math. A 4k image is probably 'bout 3800 on the long side. Ideally you'd want say 300DPI for most consumer printing. so that means optimally a 12"ish print (3800/300). You can go a bit bigger, since the printer will interpolate some pixels, but not too much. And if it's cropped obviously the dimensions will be different. You could also lower the DPI, and say go with a 24" print at 150DPI, which might work if you're looking at it from a distance.
 
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Partron22

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Apr 13, 2011
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Yes
150 DPI is usually good enough for a poster you're going to look at from a few feet away.
It won't stand up to eyeballing at 4", but that doesn't seem to be your intent.
Also, you don't want the image to be quite 36X24, as mounting in the frame will cover some of the edges.
 
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