What to do when a letter size document is not letter size.

With Photoshop you set both your document size and resolution. Printed, if you set 8.5 x 11, it will print 8.5 x 11. But, let say you make a document 8.5 x 11 at 300 dpi and the save as a jpg and email, or use for web based apps. Since 72 dpi is the screen res it will enlarge the doc size to use all data (this is layman term type of explanation, experts, please don’t yell at me), so on screen your document will appear GIGANTOMONGOUS in an email. But, Photoshop has this nifty little save for web option under "file" which allows you to preview and reduce size for on screen viewing.
Basic: anything to be "quality" printed set to "finished size" min 300 dpi/ppi.

When you open or create a document in Photoshop it opens to a magnification that will fit onscreen.

"Letter size" (i.e.: 8½in × 11 in) really means nothing in Photoshop, except for the fact that there is a preset named that way. And that preset is configured to create a document that is meant for printing, and therefore is at a sufficiently high resolution.

Photoshop, and indeed any raster image format only cares about one measurement: Pixels. Any other units of measurement that you may use are converted in the background.

Soooo, a "Letter size" document might be 612px × 792px at a resolution of 72 pixels per inch. On the other hand, and what you are probably seeing is that the same "letter size" document will be 2550 px × 3300px at 200 ppi.

Want a really good primer on image resolution—one that has been of great benefit to many, me included?

Have a look at <http://www.scantips.com>. Scroll down and start at the, well.."Start" section.

In simple language, Photoshop exists as a transition between a digital image from your camera and how it will ultimately be displayed. Your camera takes an image on a sensor that is probably a fraction of a square inch. If you have a 6MP camera, the image is roughly 3000px wide and 2000px high. You don’t care what the dimensions of the sensor in the camera are, needless to say. You don’t describe that image as .75in by .5in at 4000px/in, and your camera probably doesn’t tag it as being that "resolution." All you need to know is that the image is 3000px wide and 2000px high. The "canvas size" (what you set the "new image" to) has nothing to do with what came out of your camera; it has to do with what you plan to do with it. If you plan to print the image 6in wide and 4in high, then your canvas size should be 6" x 4" landscape.

If you open a JPEG image file from your camera in Photoshop it will arbitrarily be sized as though you planned to print or view it at 72 pixels/inch. That means that the default canvas size will be 3000/72 inches wide and 2000/72 inches high. This has no bearing on anything.
What is important is that the image is 3000x2000px.

When the file opens, it will be compressed to fit on your screen. That means that you will not be able to see every pixel. If your screen is 1024x768px, your image would take up roughly three times your screen size to display each individual pixel of the image in its own screen pixel. Instead, Photoshop displays the image within the available space on the screen. As a result, each pixel on the screen represents multiple pixels of the image.

When you tell Photoshop to display the image at 100% zoom, it enlarges the display of the image so that each individual image pixel is visible as a separate pixel on the screen. This is the best resolution for judging the quality of many image manipulations, such as sharpening or contrast enhancement. But you will only be able to see part of the entire image at a time.

Once you have done the image improvements, you need to consider how the image will be taken out of Photoshop for use. I.e., are you going to print it, put it on a website/blog, or email it? For each of these you will need to resize the image in various ways.

For printing, you need to change the dimensions of the image to the dimensions of the paper on which it will be printed and set the resolution to something reasonable for printing. For example, if you want to print it on 4×6" landscape paper, you will use Image > Image Size to change the dimensions to 4" height, 6" width. This will by default change the pixels/inch resolution and keep the actual pixels unchanged. As a result, your 3000x2000px image is now 500 px/in. This is more resolution than you need for printing at this size, so you may wish to consider resampling the resolution down to 300 px/in, which will change the pixel content of the picture, and it will now be 1800x1200px. If, instead, you want to print the image at 18×12", the resolution will be 166.67 px/in; this is at the lower end of the reasonable resolution for printing, so you might want to resample to 300, or not.

For web display, blogs, or (usually) email, you need to forget about inches altogether and think about how many pixels you want to take up on the screen, considering the various screen sizes people may have. It’s usually a safe bet these days for a prominent image to be 900 px wide, so 600x900px would be a good size for an image intended to take up most of the width of the screen. For a smaller image, use your judgment.

Where canvas size takes on the most importance is when you are doing compositing — for example when you are making a montage of several images. You need to have enough space for all the images, which may need to be resized to fit as you want them. For this purpose, I would start out with the size and resolution you intend to use for printing, and then make changes to the images to fit within that (using CS2 you can also use File > Place Image to do this without loss of data).

Ultimately, you are the one who needs to decide what size your image needs to be, and change the camera’s pixels to work properly for you in that size.

wrote in message

In simple language, Photoshop exists as a transition between a digital image from your camera and how it will ultimately be displayed. Your camera takes an image on a sensor that is probably a fraction of a square inch. If you have a 6MP camera, the image is roughly 3000px wide and 2000px high. You don’t care what the dimensions of the sensor in the camera are, needless to say. You don’t describe that image as .75in by .5in at 4000px/in, and your camera probably doesn’t tag it as being that "resolution." All you need to know is that the image is 3000px wide and 2000px high. The "canvas size" (what you set the "new image" to) has nothing to do with what came out of your camera; it has to do with what you plan to do with it. If you plan to print the image 6in wide and 4in high, then your canvas size should be 6" x 4" landscape.
If you open a JPEG image file from your camera in Photoshop it will arbitrarily be sized as though you planned to print or view it at 72 pixels/inch. That means that the default canvas size will be 3000/72 inches wide and 2000/72 inches high. This has no bearing on anything. What is important is that the image is 3000x2000px.

When the file opens, it will be compressed to fit on your screen. That means that you will not be able to see every pixel. If your screen is 1024x768px, your image would take up roughly three times your screen size to display each individual pixel of the image in its own screen pixel. Instead, Photoshop displays the image within the available space on the screen. As a result, each pixel on the screen represents multiple pixels of the image.

When you tell Photoshop to display the image at 100% zoom, it enlarges the display of the image so that each individual image pixel is visible as a separate pixel on the screen. This is the best resolution for judging the quality of many image manipulations, such as sharpening or contrast enhancement. But you will only be able to see part of the entire image at a time.

Once you have done the image improvements, you need to consider how the image will be taken out of Photoshop for use. I.e., are you going to print it, put it on a website/blog, or email it? For each of these you will need to resize the image in various ways.

For printing, you need to change the dimensions of the image to the dimensions of the paper on which it will be printed and set the resolution to something reasonable for printing. For example, if you want to print it on 4×6" landscape paper, you will use Image > Image Size to change the dimensions to 4" height, 6" width. This will by default change the pixels/inch resolution and keep the actual pixels unchanged. As a result, your 3000x2000px image is now 500 px/in. This is more resolution than you need for printing at this size, so you may wish to consider resampling the resolution down to 300 px/in, which will change the pixel content of the picture, and it will now be 1800x1200px. If, instead, you want to print the image at 18×12", the resolution will be 166.67 px/in; this is at the lower end of the reasonable resolution for printing, so you might want to resample to 300, or not.

For web display, blogs, or (usually) email, you need to forget about inches altogether and think about how many pixels you want to take up on the screen, considering the various screen sizes people may have. It’s usually a safe bet these days for a prominent image to be 900 px wide, so 600x900px would be a good size for an image intended to take up most of the width of the screen. For a smaller image, use your judgment.
Where canvas size takes on the most importance is when you are doing compositing — for example when you are making a montage of several images. You need to have enough space for all the images, which may need to be resized to fit as you want them. For this purpose, I would start out with the size and resolution you intend to use for printing, and then make changes to the images to fit within that (using CS2 you can also use File

Place Image to do this without loss of data).

Ultimately, you are the one who needs to decide what size your image needs to be, and change the camera’s pixels to work properly for you in that size.

Wow…. the terms you have explained this in is so simple, even a caveman could understand it….no this isn’t a geico commercial, but actually a huge compliment. Usually, I am sending pics of things to people, so I resize to a 4 inch width. My original file is huge, like you said, 2000, X 3000 pixels….or somewhere there abouts…
Sooo…. if I have a multitude of photos that I need to resize, is there a way I can do them all as a batch or do more than one at a time (assuming they are going to end up the same size)?

Thanks for the info Mike..

Fwed

"In simple language……………………………………………. ………… …………………………………………………… ………………………….. …………………………………………………… ………………………….. …………………………………………………… ………………………….. …………………………………………………… ………………………….. …………………………………………………… ………………………….. …………………………………………………… ………………………….. …………………………………………………… ………………………….. …………………………………………………… ………………………….. "

Heh…if you say so.

😉 XD

A short primer on view size in PS:

Unlike other softwares, the percentage does not refer to a percentage of the final output size, rather it refers to the ratio between the number of pixels used to display an image and the number of pixels in an image:

400% = 1 image pixel = 16 screen pixels
300% = 1 image pixel = 9 screen pixels
200% = 1 image pixel = 4 screen pixels
100% = 1 image pixel = 1 screen pixel
50% = 4 image pixels = 1 screen pixel
33% = 9 image pixels = 1 screen pixel
25% = 16 image pixels = 1 screen pixel
20% = 25 image pixels = 1 screen pixel