dpi requirements

Graham00

Graham00

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Graham Mc
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I've just been asked for a second photo to Photography Monthly's 2nd edition bookazine, only problem is they are asking for 300dpi A4 but PS Elements saves by default at 240dpi :thinking:
I have sent the whole 4.3mb file, i can't rememeber what happened last time it must have been 240dpi too.

If i change the highlight box from 240dpi to 300dpi by just typing it in will it save as that value ?
 
Actually for a magazine they should know better. It's actually PPI - pixels per inch (although both are commonly used ppi is the correct term).

OK Now to sort your issue. To be honest the number really doesn't mean very much when used on its own. You can save an 800px x 600px image at 300ppi. But I'm sure they will be looking for a high res image

So to answer the question use Elements and go to image size.

Switch off the tick against "resample image". Now change the ppi value to 300.

This will not change your image at all. All it changes is the physical print size if you sent it to the printer. you'll see the size in inches fall but the number of pixels in the image remains the same.

Why people use the term dpi I don't know and why they ask for 300 really cracks me up!

If they said we need a 3000 x 2400 pixel image, that would make far more sense. At 300ppi that would print at 10" x 8".

Anyway I digress. Just switch off resample, enter 300 into the ppi box and click ok. Job done.
 
Graham00 said:
If i change the highlight box from 240dpi to 300dpi by just typing it in will it save as that value ?
Click to expand...

Just to add yes it will but if resample is clicked your image will become larger - which you probably don't want.
 
EOS_JD said:
Just to add yes it will but if resample is clicked your image will become larger - which you probably don't want.
Click to expand...
If it's A4 at 240ppi and you change it to 300ppi without changing the number of pixels in the image, the image will print smaller and won't be what the magazine want (300ppi A4 image).
 
arad85 said:
If it's A4 at 240ppi and you change it to 300ppi without changing the number of pixels in the image, the image will print smaller and won't be what the magazine want (300ppi A4 image).
Click to expand...

Know what I missed the A4 part :) So i take back some of what I mentioned above. They have indeed provided the size so all you ned to do is take the x & yaxis values and multiply by 300


Px = Ps x R

Where
Px = pixels (per axis)
Ps = Print Size (per axis)
R = resolution

To send as A4 @ 300ppi you need

8.24" x 300 = 2472px
11.69" x 300 = 3507px

If your image is smaller or larger you will need to resample to achieve the target size.

Sorry for missing the A4 size part :)
 
Simply resize to 300 dpi in Elements. It's the page design software that gets grumpy when the image isn't at 300dpi, as the designer then has to resize it.
I had this several times a few years ago , and now default everything to 300dpi. Saves a lot of hassle
 
Chappers said:
Simply resize to 300 dpi in Elements. It's the page design software that gets grumpy when the image isn't at 300dpi, as the designer then has to resize it.
I had this several times a few years ago , and now default everything to 300dpi. Saves a lot of hassle
Click to expand...

You mean PPI (it's not dpi - that is a printer/scanner setting)

Simply resizing may not be the way to work as it depends on the image. if you have cropped your original and you don't have the number of required pixels you need to be slightly careful how much you upscale the image although for most purposes it should be ok.

Very simple to understand with the simple equation above.
 
EOS_JD said:
You mean PPI (it's not dpi - that is a printer/scanner setting)

Simply resizing may not be the way to work as it depends on the image. if you have cropped your original and you don't have the number of required pixels you need to be slightly careful how much you upscale the image although for most purposes it should be ok.

Very simple to understand with the simple equation above.
Click to expand...

Most page design software, such as InDesign, or Quark use dpi not ppi. This refers to the ink on paper resolution not the image resolution. This is the only resolution print designers care about not the original image file size. I've had many a long "discussion" about this with designers. They have the final say so I now take the easiest route
 
Chappers is right, DPI has always been used in the prepress department, and believe me it still is today.
 
It's got me thinking now, if i print A4 right and the file is 240ppi, will i see any noticable difference if i print 300ppi ?
 
Chappers said:
Most page design software, such as InDesign, or Quark use dpi not ppi. This refers to the ink on paper resolution not the image resolution. This is the only resolution print designers care about not the original image file size. I've had many a long "discussion" about this with designers. They have the final say so I now take the easiest route
Click to expand...

If only everyone thought like that, it would make my job as a designer easier :D
 
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Graham00 said:
It's got me thinking now, if i print A4 right and the file is 240ppi, will i see any noticable difference if i print 300ppi ?
Click to expand...

In a word - No

240ppi is plenty resolution.
 
Chappers said:
Most page design software, such as InDesign, or Quark use dpi not ppi. This refers to the ink on paper resolution not the image resolution. This is the only resolution print designers care about not the original image file size. I've had many a long "discussion" about this with designers. They have the final say so I now take the easiest route
Click to expand...

You are not talking about the same thing.

In Indesign try inserting a 72ppi image and printing it at 300dpi. Now you will see who is correct.
 
Chappers said:
Most page design software, such as InDesign, or Quark use dpi not ppi. This refers to the ink on paper resolution not the image resolution. This is the only resolution print designers care about not the original image file size. I've had many a long "discussion" about this with designers. They have the final say so I now take the easiest route
Click to expand...

You are not talking about the same thing.

In Indesign try placing your images @ 72ppi into the indd document and then let your printer print it at 300dpi. Now do the same and insert a 300ppi image into the document anmd print it at 300dpi.

What looks better?

Now you will see why your argument isn't holding up. Indesign is a totally different beast to photoshop and does not deal in itself with resolution in the same way. Indd (and QE) are page layout programs - The page itself does not have a resolution but the images contained within it absolutely do. Look at the Document Setup - nowhere does it mention resolution as that is only set up when you actually print the document so dpi is indeed the correct term for use at that stage.

I absolutely understand that dpi is a printing term. But you cannot resize an indesign document to 300ppi or dpi. What you do is print at that resolution.

The printers machines that print indd docs are not the same as your labs printer either. Indd docs are most likely printed on prepress printers for the output.
 
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Scotty Pro said:
Chappers is right, DPI has always been used in the prepress department, and believe me it still is today.
Click to expand...

Where did I mention this above - You are both confused as printing lab images does not involve prepress printers - Prepress is used for creation of books and brochures and the like and is a totally different process although some parts are similar

Youcannot resize an indesign document by changing resolution as these docs do not have a resolution - they have a fixed size - but can be printed at varying resolutions which affects only the quality of the image - not the size.

When changing the resolution of an image in Ps, you are changing the physical size it prints.
 
htid said:
If only everyone thought like that, it would make my job as a designer easier :D
Click to expand...

Now I'm really worried! A designer that doesn't understand the difference!!! So glad the designer I use knows exactly what is required!
 
Screen_shot.jpg


the above image is a jpeg dropped straight onto an A4 page at 100%, the actual and effective size is shown in red.
 
Scotty
I'm patient so I'll spell it out

The JPG Image has a resolution - not the indd document! You'll also see that the resolution is in fact in ppi - NOT dpi!

Also please note that is not a jpg at 100%

At 100% the actual PPI of 72ppi means the image would be much larger. What has happened is that the image has been inserted at 72ppi and then reduced in physical size giving the effective resolution of 432ppi.

Would you agree now?

Indd docs do not need to have a resolution - the images contained within t most certainly do. That resolution is still measured in ppi. Only when printing is it measured in dpi and the dpi is the printers resolution. I printg indd docs on my Epson R2400 at 1440 dpi (effective resolution is 180dpi) - All my images though are usually at native resolution although it depends on the size I need the final document.
 
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