Frequency

[Bradley_Sakdol@adobeforums.com]

How do you change the frequency of an image before printing? I need to change the freq. on my image to 45.

[Ramón_G_Castañeda@adobeforums.com]

[Deleted - Wrong Thread]

[Ramón_G_Castañeda@adobeforums.com]

Bradley,

It looks like you edited your post. Here's the answer to your original post:

It's PPI not DPI. Pixels per inch; the image doesn't know about dots, only the printer does.

Go to Image menu > Image Size > Document Size > Resolution (pixels/inch). Make sure the Resample Image is NOT checked.

[JasonSmith@adobeforums.com]

He may be thinking about LPI frequency...?

[Ramón_G_Castañeda@adobeforums.com]

Jason,

Yes, that's what the edited post says. Originally, Bradley had asked about changing "DPI", that's why I replied the way I did. By the time my reply got posted, he had totally changed the topic and the question so that I thought I had replied to the wrong thread.

When I went back to the index, I realized it was the correct thread, but the poster had changed his mind. I simply replied to the original question, and ignored the new one for fear he'd change his mind again. :)

[JasonSmith@adobeforums.com]

well that's about all it takes to confuse me.

[Bradley_Sakdol@adobeforums.com]

OK... The original post asked about the DPI (PPI), but then I figured that out. The next issue, was changing the frequency (LPI). I am doing photo editing work for my school newspaper and am having problems getting the photos right. I was given these specs for the photos:

Frequency (LPI) - 45.0
DPI (PPI) - 71

So [now] how do I get the LPI to 45 once the photo is open in Photoshop?

Sorry about the confusing you by changing the topic completely!

[Todie@adobeforums.com]

You don't have to, but can change the picture's mode to bitmap.
The RIP would do it for you when printing to film or plate.

[John_Slate@adobeforums.com]

45 LPI??? That is way course even for newspaper printing

What for? What exactly are you trying to do, what is your output device and how is your output going to be used to produce the newspaper?

You don't mean 45 degrees do you?

You should not have to worry about halftoning, and even if you did, it would not normally be done in Photoshop as Todie has suggested.

The only time you would do this is if you really need halftone dots, and all you have to print to is a laserprinter that uses FM screening.

[Todie@adobeforums.com]

John, A loooong time ago, I did some newspaper paste-up work from laser prints prepared in Photoshop that were shot on film at 50% : ) for the final layout.

85 line isn't unusual for newsprint.

.... and I did a lot of bitmapping of plates for silkscreening
('cause I needed wired angles, in Photoshop)

[John_Slate@adobeforums.com]

Good one LT.

However if these guys are doing paste-up, I'll eat my hat.

[Todie@adobeforums.com]

I don't think they do either, but it doesn't mean that bitmapping shouldn't be done.

Several times I did it because I was too lazy to change the imagesetter's resolution : )

[JasonSmith@adobeforums.com]

John, you wear a hat? What kind of hat?

[John_Slate@adobeforums.com]

Waterbuffalo lodge member hat

[bradley_c_sakdol@adobeforums.com]

Ok... N/m, the newspaper that actually prints the paper is coming over to my school to help out so... thanks anyway!