Any pre-press tips, please? 4

[PetitPal]

Dear All,

I've been asked to do some adverts for a magazine recently and I've never really done any stuff for print before; just for screen.

The last advert I did looked fine on screen but, obviously, looked horribly pixelated when printed and the colours where very dodgy too. I've worked out that the colour thing is because I need to optimize it in CMYK mode but I can't think of a way round the pixelated stuff (bear in mind I have to do a half A4 ad. and can only submit in TIF, JPG or GIF format).

Basically then, does anyone have any tips? Anything would be v.v.v.much appreciated. Thanks!

=)

PetitPal

 

[PetitPal]

In reply to my own question (!) apparently you just have to draw the image at about 4x half-A4 size. When you print it off at half-A4 size the res is lovely.

I'm sure you all knew this anyway... but there you go!

Newbies, eh?

=)

PetitPal

 

[carlow]

Hi

When you make an ad for print one of the things you have to keep in mind are the lpi's (not the dpi's) of the printshop.
let's say your ad will be printed at 133 lpi's, your scans and the total of the ad must be two and a half times bigger than the 133 lpi's.
So a scan which is used at 100% must be at least 312 dpi.If you use only a portion of the scan that you wan't to increase in size in your ad you must multiply the 312 dpi by the factor you use for the portion of the scan.
So if you use a third of the san and enlarge that portion 4 times, multiply the 312 dpi,'s by 4.

Hope this helps
.

grillhouse

 

[PetitPal]

Hi grillhouse,

Thanks for the info., just one quick question though; is there a meaningful conversion between lpi and dpi? So for example is it possible to say that, for example, 'x' lpi is equivalent to 'y' dpi, or is it meaningless to convert between the two? If you see what I mean?

Thanks!

=)

PetitPal.

 

[carlow]

Hi,

The terms stand for two different things.
Dpi's are important for scans and digital stuff.
Lpi's is the screen with which the printing machine is printing. For example a magazine printer uses a screen between 120 lpi and 150 lpi. A newspaper press uses 85 lpi up to 100 lpi. This is due to the printing style, offset....

So the lpi's are important for the dpi's you would use a factor of two and a half times the lpi's to know how you're dpi's must be set. This in the knowledge that the document isn't enlarged. Cause then you must increase the dpi's of your scans.

By the way: resampling an image that has been scanned at a lower dpi rate in Photoshop to a higher dpi rate is not the same as scanning an image at a higher resolution.

Don't exagerate on the dpi's because when the file is sent to a imagesetter it will take an enormous time to make the calculations and your service bureau will not appreciate this. The rip of the imagesetter will first calculate the large image and write it to disk, when this is done, the rip will recalculate the needed information that can be displayed when printed to for example 85 lpi's, and only then is going to throw away all the useless information.

.

Grillhouse

 

[zefir]

A typical offset print for a magazine uses 2400dpi/150lpi
for the imagesetter.
The images on the paper should have (1.5..2) pixels per raster cell,
in this example 225..300 pixels per inch.
In normal DTP (PageMaker), the text is not transferred as an image.
If you use a completely rastered page in PhS for text (opposed to
vector text), the page resolution should be at least 300dpi or much
better 600 dpi. The imagesetter can create crisp text with 2400 dpi !
In PhS6 vector text is possible (no experience - I use PhS5).
---Gernot

 

[PetitPal]

Thanks for all the info. this is exactly the kind of stuff I need to know but don't seem to be able to find anywhere else!

Thanks again,

=)

PetitPal.

 

[zefir]

Petit: you are welcome. --Gernot

 

[zefir]

Petit: you are welcome. --Gernot

 

[papajoe]

Zefir:

My dear friend Gernot...Is this not the same info I was inquiring about some time back. Strange that nobody offered the formula suggesting dpi should be 2.5 times that of the dpi. Also--Are you certain about the advice you gave suggesting 600 dpi is better than 300 dpi?
BTW...I never received a reply on my question about how to get the "pen" cropping effect on PhS 5.0 It apears on the sample version of 6.0 that you can download free (50MB), but that version won't allow you to save or copy your work. Which, to me, makes the whole venture fruitless. How do I know if it will inprot into PM6.0?

Regards,

PapaJoe32@aol.com

 

[zefir]

Dear Papajoe, because of these questions about
dpi and lpi, I have made a poster, where I try to explain
this with some illustrations ( 90 kBytes).
I am not a PhotoShop expert . In fact I use an own
image processing system. That´s the reason I can
only give general recommendations (Computer Vision).
I am a little more experienced in PageMaker and DTP.
Best regards ---Gernot

http://www.fho-emden.de/~hoffmann/colrend290800.pdf