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Canvas size and image size?? - Printable Version

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Canvas size and image size?? - Bond007 - 02-26-2008 04:07 PM

what is the difference between image size and Canvas size in Photshop??


RE: Canvas size and image size?? - Martin - 02-26-2008 07:44 PM

Image size means the number of pixels in a unit area. when you resize a picture it merely spreads out or scrunches the image pixels. Pixels spread out image gets bigger.
On the other hand, if youre trying to make an image larger, and still keep your current dpi, well then PhotoShops got its work cut out for it. To make an image larger, PhotoShop must spread pixels apart. To keep resolution the same while stretching, PhotoShop must add new pixels to the image and decide what color they should be. When shrinking an image, PhotoShop must decide which pixels to remove.
PhotoShop is really good at adding and removing pixels, but you can generally only increase or decrease size by about 1/3 before images start looking yucky.

Then if you just need more space in the PhotoShop window, maybe youre trying to place two images next to each other, or add some text next to an image, then you have to go for canvas size.
Just like a painting is on a canvas, PhotoShop images are also on a canvas. If you need to add extra space in an image, youll just change the canvas size. The picture wont get any bigger or smaller, but there will be more space around it.


RE: Canvas size and image size?? - Tommy - 02-27-2008 09:54 AM

Changing the canvas size, it creates more work space.
Changing image size, If you are trying to increase image size it will add more pixels,
actually what is happening is adding and removing pixels.


RE: Canvas size and image size?? - Martin - 02-27-2008 06:15 PM

Pixel is the shot term of picture element. Graphics monitors display pictures by dividing the display screen into thousands (or millions) of pixels, arranged in rows and columns. The pixels are so close together that they appear connected.
so if you increase the number of pixels file size will increase and vice versa.


RE: Canvas size and image size?? - maxcreigs - 02-25-2010 03:58 PM

When working with an image-editing program, such as Adobe Photoshop, you can modify both the image size and canvas size of an image. While they sound similar, they modify the image in two different ways.

When you modify the canvas size of an image, you either increase or decrease the amount of area of the image canvas. This means that adding to the canvas size will add blank area around the image (or fill it with the background color if there is only one layer). Conversely, if you decrease the canvas size, the image will be cropped, meaning you will lose some of the image depending on where you crop it.

When you modify the image size of an image, you change how large the image is. When you increase the image size, the image will appear bigger, and may become blocky or blurry if increased too much. Decreasing the image size will shrink the image, and may cause some detail to be lost. When you change the image size, you can also modify the image resolution (in DPI), and stretch the image by unchecking the "Constrain Proportions" box. Unlike changing the canvas size, when you change the image size, the original image still fills the whole window.

So if you want to add more area to an image or crop a section of it, change the canvas size. If you want to shrink, expand, or change the resolution of an image, adjust the image size.


RE: Canvas size and image size?? - peteraugusts - 04-05-2010 12:46 PM

When working with an image-editing program, like Adobe Photoshop, in that you can modify both the image size and canvas size of an image. They modify the image in two different ways. When you modify the canvas size of an image in photoshop, you either increase or decrease the amount of area of the image canvas. This means that adding to the canvas size will add blank area around the image and When you modify the image size of an image, you change how large the image is. When you increase the image size, the image will appear bigger, and may become blocky or blurry if increased too much. Decreasing the image size will shrink the image, and may also cause some detail to be lost.

* Canvas Size will allow the dimensions of the drawing board to be changed
* Image Size will allow the dimensions of both the image and canvas to be changed together – and for the resolution to be changed.



RE: Canvas size and image size?? - ritzbhogal - 07-01-2010 11:05 AM

The Canvas Size allows you to expand or contract in any given direction the dimensions of canvas on which you image is placed while image size resize your images means increase or decrease the size of the image.


RE: Canvas size and image size?? - mikehykes - 01-29-2011 04:22 PM

When you change the canvas size of an image, increase or decrease the amount of image area of the fabric. This means that adding the size of the canvas will add the empty space around the image.


RE: Canvas size and image size?? - harman - 12-27-2011 01:04 PM

I want to crop pixels from above and one part of right side of image in this case. First thing to do is to display Canvas Size dialog from Image .