Enlarging an Image

[desireerose]

I have an image that is at 500 resolution and I need to make it banner size like 3 ft by 5 ft and the enlarging process is causing alot of trouble.. Can anyone help... It loses it's clarity and gets pixilated..

[desireerose]

I have an image that is at 500 resolution and I need to make it banner size like 3 ft by 5 ft and the enlarging process is causing alot of trouble.. Can anyone help... It loses it's clarity and gets pixilated..

[Thelonious]

Howdy.

Well there are two things to know here. One is that when increasing the size of an image you can uncheck resample and the file size will remain the same. If you increase the size and ask photoshop to resample then it will increase the file size and photoshop will have to add pixels. It uses bicubic interpolation to do this. The result is a somewhat blurred image due to the fact that Photoshop has to put in information that isn't really there.

There are a couple of programs that deal with this problem specifically. They claim to use fractal technology to get a better result than bicubic. However, although some people say it's very good I've checked it out and my personal opinion is that it is pretty ho hum. You can achieve adequate results using bicubic with some judicious sharpening.

Having said all that, one comes to the real question which is what resolution do you really need? This is a much more pertinant question. For high quality sheet fed coated paper or very fine home inkjet printers you will find that 300 dpi is about as big as you would want to go. In fact you can lose sharpness if you go higher.

For publication on the net you only want screen resoltion of 72 dpi. If you are printing a big banner you should talk to the people who will print it because they will advise you on how little dpi you can get away with. You also need to take into account how close it will be viewed. 3 by 5 feet is not that big. You can print that out on the average commercial inkjet printer. My experience is that you can get away with as little as 120 dpi in this instance. I've seen banners printed at 72 dpi that don't look half bad.

For starters you can uncheck the resample checkbox in the image adjust>image size command and change it from 500dpi to 120 dpi. Then have a look at the new size. That will be about as big as you can print it and be pretty sure of good quality. But you would probably be better off going for 100 dpi rather than increasing the file size. You bureau would be the best people to advise you on this.

[desireerose]

Well I have been playing with it and my frustration level seems to be soaring.. Is there a way to send you the file and see what you think.. I am willing to start over with it but the graphic will not even save right for the web now..

[vector]

Can you even open the "save for web" feature in PS?

If it's too large, PS won't be able to handle that.

Pixel dimension for an image of that size, you can get away with 800X600

[Thelonious]

Let's see if we can sort this out here.

OK you can open the file in photshop OK. Yes?

Do you know if it is a tiff or jpeg or gif? Go to edit>mode and see what is ticked. Is it RGB?

Next go to edit>adjust>image size. What size does it say. What resolution does it say. Make sure the resolution is set to show dots per inch and not d per cm.

Now apparently it is already showing 500 dpi. Is this correct?

Do this. Uncheck the "resample" box then change the dpi to 120. You will notice that the dimensions of the image have changed. The file size (at the top of the dialog box) will not have changed.

Write down the new image size then cancel the box. Close the image. Do not save. Report back here. We'll take it from there depending on what the new image dimensions were that you wrote down when you changed the dpi to 120.

[desireerose]

The dimensions after the change were 5.883 x 2.225 ? Is that a good thing or a bad thing?
thanks for your help..

Desiree Rose

[desireerose]

the dimensions are 5.883 x 2.225 is this helpful?
THanks for your help..
Desiree

[vector]

How did you capture the image to 500 DPI?

[Thelonious]

5.8 x 2.2 eh?

Whether that's a good or bad thing depends on whether we are talking in metres feet inches or centimeters. It will say in the dialog box.

Alternatively at the top of the dialog box you will have the absolute size in pixels. So let's have this info.

However my gut reaction is that this is going to be a bad thing. Anyway let me know the size (including what measurement system it refers to)

Also what is the image of? is it a photo or is it a graphic image or text.

Post the image here (as long as it's legal) Go to Image>image size, make sure the resample box is checked, then change the resolution from 500 to 72 pixels per inch. Then go to Save As and select jpg from the drop down menu. In the option box that pops up set the quality to 1. Press OK. This will save a tiny jpg image which you can post here. Close the original file without saving.

The reason I'm asking you to post it here is to see if it is something that can be remade easily in Photoshop, at the size you need. If the image is a photo then don't bother.