Changing canvas size to a smaller one will force the image to resample according to the settings in Preferences (e.g., bicubic), if I recall correctly. Using the options bar with the crop tool, if you do not specify the resolution, it’s a simple (but precise) crop.
If you do change canvas size, remember to crop the whole page, other wise you still have active graphics outside of the canvas area, resuliting in larger files than needed.
T_DO:
Can you please explain that further. What do you mean "crop the whole page"? When you change canvas size you always crop. Are you confusing with the "hide" option on the crop tool?
probably, yet another retraction from me. I’ll get my coat.
T_DO: :-)) [you must be English …]
No no…that would only "warp" the image in this case.
what would?
Very best way in this situation is use rectangular marquee. Style: Fixed Size
Type in 760px and 540px
Click on image, move where you want cropped.
Image/Crop.
If you try the same thing with crop tool, you’ll invariablly be interpolating one way or another.
Mac
No no…that would only "warp" the image in this case.
Mac
what would?
Oh, I read that as changing Image/Image Size
rather than Image/Canvas size
(Andrew’s post). Sorry.
It would indeed work, although you’d have only the option of taking the entire "crop" from top or bottom as in original example from OP. The rectangular marquee method allows you to precisely move it around before deciding.
Mac
Mac…why not just use the Crop Tool in the same manner you prescribe for the Rectangular Marquee?
Hit "OK" after proper positioning and you’re done.
Oh, I read that as changing Image/Image Size rather than Image/Canvas size (Andrew’s post). Sorry.
I did too at first, then had to revise my post.
why not just use the Crop Tool in the same manner you prescribe for the Rectangular Marquee?
I’m a crop tool biggot. It’s too final. I like to ponder my destructive actions before committing them! :Þ
Mac…why not just use the Crop Tool
Because you will not necessarily be cropping only original pixels.
You can pull a tiny area from whole image, and it will interpolate UP to that to match pixel dimensions you select.
Using rect. marquee will only use original pixels, no chance of upsampling.
Mac
"Because you will not necessarily be cropping only original pixels.
You can pull a tiny area from whole image, and it will interpolate UP tothat to match pixel dimensions you select."
Not if you don’t want to.
I RARELY use the Crop Tool and set it to resize. The only instance I can think of where I’ve used the Crop Tool that way is when I want to create a specific sized 72 ppi personal avatar for use in a forum from a high-res photo of myself.
I RARELY use the Crop Tool and set it to resize.
Phos, the crop tool will in almost ALL situations resample the image, if you set it for precise pixel dimensions unless you are extremely careful to make sure the largest dimension is using original border of the image.
In flavor of original example:
you have 800×600 image.
You want to crop to 800×500 image.
ANY crop with crop tool wherein you type 800×500 px will upsample image unless you ensure your crop border extends to entire outside edge of image.
If you crop into the image at all to get your 800×500, you are usampling fewer original pixels back to the 800×500.
This can’t happen with rectangular marquee set to fixed size.
Mac
Hmmm…
Down I go to the Pixel Dungeon for some research…
All you have to do to prove/understand with crop tool is:
1. look at original pixel dimensions of image
2. set pixel dimensions at exact same as original
3. crop into image some.
Obviously, if you take less of the picture, using same number of pixels as you started with, you are interpolating fewer pixels up to more pixels.
Then do same thing with rectangular marquee.
You’ll find you CAN’T make fewer pixels into more pixels as you can with the crop tool.
Mac
No,not exactly.
Obviously, you can take fewer pixels than originally with either method. The trick is knowing at what point you are grabbing fewer *real* (original) pixels. In your example, if using the crop tool, you could have selected 1×1 pixel and told it to be 6×6 pixel. But you can’t do this with rect. marquee.
Simplest way to splain:
Make an 800×600 pixel image.
With crop tool, set crop at 800×600 pixels.
You can crop ANY area with that, yes? Even a very small section. It then interpolates whatever you have cropped to 800×600. Since you only started with 800×600, obviously it has upsampled.
Now do same thing with rectangular marquee. You’ll see that 800×600 pixel selection can ONLY select the ENTIRE IMAGE. No interpolation possible. Or grab your 6×6 pixel area out of it, and it will be valid.
The overriding point is that most funtions that folks want to perform like this, if they use the crop tool to do it, there’s a VERY good change they will upsample actual pixels into interpolated ones. Not possible with the rect. marquee method.
Mac
Dave:
The crop tool is not necessarily final. You always have the hide option [if you normalise the background layer, you don’t actually lose any data at all].
Mac is right.
A Xpixels by Ypixels rectangle defines an area in a file that is a fixed size, right? When you use the marquee, you get that one fixed size which you can move around to crop out the section you want.
When you use the crop tool set to fixed size, on the other hand, you have a variable sized rectangle which will only retain the same aspect ratio of the pixel dimensions that you have specified. But it can be resized larger or smaller than the actual pixel dimensions you have specified. So Phosphor could have set his crop tool to 36×36 but the only thing that would have done is to restrict his crop tool to a square… a square of any size that would fit inside his canvas. When he invoked the crop command he would have resampled whatever square area he chose up or down to 36×36, that is unless he was careful enough to crop out a 36×36 area to begin with.
So Phosphor could have set his crop tool to 36×36 but
the only thing that would have done is to restrict his crop tool to a square… When he invoked the crop command he would have resampled whatever square area he chose up or down to 36×36, that is unless he was careful enough to crop out a 36×36 area to begin with.
All exactly right, John, and more succinctly said than my roundabout explanation, methinks.
Matter of fact, with the crop tool, I don’t know of any way you necessarily *could* know when you’ve actually selected the exact number of real (original) pixels you may have specified in the w/h dialogue – unless one of your dimensions is the same max dimension of the image itself and you’re careful to make that crop dimension same as outside edge *of* the entire image.
Mac
I never noticed that colin! Thanks. How do I unhide? 🙂
Nevermind… F1 to the rescue!
# Do the following in the options bar:
* Specify whether you want to hide or delete the cropped area. Select Hide to preserve the cropped area in the image file. You can make the hidden area visible by moving the image with the move tool. Select Delete to discard the cropped area.
OK. I can move it around and get different parts of my image into the cropped area. Is there any way to restore to a larger area of the image or is THAT final?
