This looks long and complicated. It is long, I tried to cover all the bases, but each section gives you the easy way to do what you need to do, and then a more detailed explanation of WHY if you want it.
I use several different programs depending on the task. If you use one that I haven't mentioned, this may be of limited use to you, but perhaps it will put you on the right track.
Why do you need to resize your images?
Short answer: "BECAUSE".
There are a several reasons.
- A photo taken by a modern digital camera can be HUGE. Even the latest round of SmartPhones have 41Mp sensors: each photo could be 50 megabytes in size! That takes up a lot of room on the server, it takes forever to upload it, and people trying to download it use up a lot of bandwidth just to see your picture.
- For similar reasons, some sites have limitations on the maximum size they will accept. Most of the forums are like that: for example, TIF (The Imaging Forum) has a limit of 800 pixels wide.
- Some sites will allow you to upload huge pictures, then they will reduce the size that they display. FaceBook and SmugMug come to mind. In the case of Facebook, it's well known that the methods they use to reduce your picture to a reasonable size will degrade the picture, both the colour and the resolution, and introduce 'artifacts' that weren't in the original picture.
- If you're trying to view a picture on your computer, most monitors are only capable of displaying between 1000 and 2000 pixels wide. So a full-screen image on the biggest monitor is going to be less than that. The same thing is true of projectors, which might be used to evaluate your images. And finally,
- If you upload a full-resolution image, people might be able to steal it and make prints from it or sell it, or claim that it is their own. If you put up a reduced size, it's not printable.
What size do you want your images to be?
Short answer: depends what you're trying to do with it.
Here and there you're going to see boxes that let you choose the resolution. You might see numbers like "240 pixels/inch" or "300 pixels/inch" or "72 pixels per inch". Generally the resolution doesn't matter at all. The device you're sending it to will decide. Unless you want your picture to be a certain size in inches, like you would when you print. Multiply the number of inches by the number of pixels/inch and it will tell you how many pixels you need. Work in pixels, not inches.
For uploading to the internet:
- Normal images should fit inside a frame that's 800 pixels wide and 600 pixels high.
- Large images should fit inside a frame that's 1280 pixels wide and 1024 pixels high.
- Facebook will give you sharper images if you use 2048 or 960 pixels on the long side (height or width). Don't ask why. It will resize it anyway to fit in its framework.
- Most monitors show only 72 dots per inch. So if you make your images fit inside 1280 pixels wide by 1024 images high you'll have a picture that's 18" wide and 14" high. Big enough?
- iPads have higher resolution. Go for 2048 pixels on the long side. (New iPads might be even higher, but I don't know, I don't have one!)
- Our projector likes images that are 1280 pixels wide by 1024 pixels high. Don't exceed these dimensions.
- Of course your picture might be very wide or very tall: remember to keep the maximum dimension inside that frame.
- Printers work best around 300 dots per inch. So to make an 8x10 print, you need about
2400 x 3000 pixels. - Most people can't tell the difference if you have only 200 dots per inch. So 1600 x 2000 pixels might be enough.
How do you resize images?
That depends on what software you're using. Pretty well all of them have that capability, so if you're using one I don't mention here, hopefully you will be able to figure it out.
Photoshop Elements
Short answer: Go to Image → Resize → Image Size. Make sure "Resample Image" is selected. Change the number of pixels in the "width" or the "height" boxes to whatever you want. Press "OK". "Save As..." and give it a new name ending in '.jpg'.I only have an older version (10) of Elements, so your screen might look a little different if you have a newer one. It should be very similar, though. If you have an image open, go to the "Image" menu, drag down to "Resize" and over to "Image Size". You can also use a keyboard shortcut, on Windows machines it's Ctrl-Alt-I, on Mac it's Opt-Cmd-I. In both cases, you hold down the modifier keys (ctrl, alt, etc) and touch the "I" key.
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The image I have open here is 6000 px wide by 4000 px high. You'd think that's "ONLY" 24 megabytes, but what you don't know is that there are several layers in this shot and it's over 250 Mb! If you tried to upload it, just 4 pictures this size would be a full Gigabyte! Besides, it's the wrong format. Keep reading! |
Now when you open the dialog box, you'll see a window like this:
First thing you need to do is to put a tick mark under "Resample Image" at the bottom. That will activate the pixel dimensions in the upper circle. What that does is to tell Elements you want to change the actual number of pixels in the picture. Now if you go into that upper box (where it says "6003" and change that to "1280" it will automatically change the height of the picture to 853 px (where it now says "4001"). What's going on?
The original picture has a certain "aspect ratio": in this case, it's about 3x2. That means that the height is 2/3 of the width and you want to keep it that way, or it will get distorted! That symbol on the right side of the box shows that you are locking those two values together, and that's what the "Constrain Proportions" tickbox is about.
Elements is designed for people who just want to do regular prints, so it gives a default resolution and size for printing. That "240 pixels/inch" number that you see under resolution is for that. You can safely ignore that box, in fact the whole "document size" area if you're just resizing in order to upload your image.
If you click "OK" at this point, suddenly the picture looks really small on your screen! Well that's because it IS smaller than it was.
If you click "OK" at this point, suddenly the picture looks really small on your screen! Well that's because it IS smaller than it was.
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Just click the "Fit Screen" button at the top (or use the keyboard shortcut "Ctrl-0" or "Cmd-0" (that's a ZERO not the letter OH ) to look at it full size. In this example, I've reduced a 250Mb image down to 11 Mb and I defy you to see a difference on your screen! |
Next step is to save your image in a format that can be uploaded on the web. BE CAREFUL HERE. If your original image was a JPEG, and if you just click "Save", you will erase your full sized image and write over it with the little version! You need to give it a new name so that your original image will be untouched. Select "SAVE AS" in the menu, not "SAVE".
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This dialog box will open. You need to do two things: first, select "JPEG" as your file type (green arrow) and then give it a new name (I would call this one 'redumbrella'. I try not to put spaces in the filename when I'm putting an image up online). |
After you do these things and click "Save", you will have stored the picture on your hard drive, ready to be uploaded.
Note: It took me MUCH longer to type this than it does for you to do it. Two steps: resize the image and save it under a new name. Make sense?
Now here's the same technique for Photoshop (CS, or CC or...)
Photoshop
Short answer: Go to Image → Image Size. Make sure the width and height are showing in pixels, not inches or cm. Change the number of pixels in the "width" or the "height" boxes to whatever you want. Press "OK". "Save As..." and give it a new name ending in '.jpg'.Ready for this? It's EXACTLY THE SAME AS ELEMENTS. The dialog boxes look a little different, but the functions are the same. These programs were written by the same people!
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Just go into the width box and type in 1280. Then when you click "OK" the image will be small, so click "Fill Screen" or "Fit Screen". Note that the box to the right of the Width box has to say "PIXELS", not INCHES. If it says "Inches", you're going to try to make your picture 1,280 inches wide, or over 10 feet wide! Not good! |
The dialog for saving the picture is EXACTLY the same as it was in Elements. OK?
Lightroom
Short answer: Go to File → Export. Tell it where to put the picture. Make sure "resize to fit" is selected and the width and height are showing in pixels, not inches or cm. Change the number of pixels in the "width" or the "height" boxes to whatever you want. Make sure the file settings are "Jpeg" and "sRGB". Click "Export".This one's a little different. Lightroom is a program designed to catalog and store your original files, no matter what kind of images they are. Sort of like storing negatives in the old days. So to output a picture, you want to EXPORT it. And normally you wouldn't store the exported image in your Lightroom Catalog, just the same way you wouldn't store a print in your negative file in the old days.
OK, so when you have a picture selected onscreen in Lightroom, choose "Export" from the file menu.
A new dialog box will open. Now if you haven't created a bunch of custom presets (if you're reading this, you probably haven't!), you can ignore the whole left side.
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Notice where it says "Export One File" at the top? If you had selected 100 files, you could export them ALL with one keystroke! That's a lesson for another day! |
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If you scroll down, this is the rest of the dialog box |
What you want to do is tell Lightroom
- where to put the file
- what to call it
- what kind of file it is
- what size it should be...
- ...and a bunch of other stuff that's not important here and the subject of another lesson.
So the first two are obvious. Store it wherever you want, call it whatever. The third one is important: you want it to be a JPEG. And make the quality around 80%, you won't be able to tell the difference and it'll be much smaller. Type in the size you want. If you choose "Width and Height" here, you need to put in both numbers. What you're doing is defining a frame to fit the picture in and how it fills the frame depends on its shape. In the example we've been working on, I've used 1280 x 1024 pixels. In the screenshot above, 800 x 600 pixels is keyed in. Click "OK" and you're done!
In Lightroom you can save these preferences so that next time they'll already be in there and you just have to click "Export".
In Lightroom you can save these preferences so that next time they'll already be in there and you just have to click "Export".
What about uploading?
Now you have this newly created, resized picture on your hard drive, how do you get it up on the internet?
Again that depends what you're doing with it and what programs you have in your computer. Let's take the simple ones first.
Short Answer: these are ALL short answers. There are so many different programs and systems out there! If you're confused, especially if you're an HHCC member, get in touch and we'll see what we can do.
FaceBook, Google+, Smugmug
When you open any of those sites, they have simple uploaders in place. You can either drag the picture into the dialog, or you can browse for it on your computer and then click "Open" and it will be automatically done for you.
Simple stuff.
FlickR or other picture sites
I dunno. I don't use them. Probably just as simple.
Your own webspace
If you have your own webspace, you know that's a place where you can upload pages or images or whatever kinds of files for other people to access.
I have my own websites. Generally the Internet Service Provider (ISP) who is hosting your site will tell you how to upload files: it's usually through a mechanism called "File Transfer Protocol" or FTP. There are lots of FTP programs out there.
Details on how to do that are for another day.
FlickR or other picture sites
I dunno. I don't use them. Probably just as simple.
Your own webspace
If you have your own webspace, you know that's a place where you can upload pages or images or whatever kinds of files for other people to access.
I have my own websites. Generally the Internet Service Provider (ISP) who is hosting your site will tell you how to upload files: it's usually through a mechanism called "File Transfer Protocol" or FTP. There are lots of FTP programs out there.
Details on how to do that are for another day.
Forums, like TIF
Most of the forums use the same software. When you join a forum, you will find sticky instructions on how to upload to it in their FAQ section.
Basically there are two ways to get an image into a forum:
Most of the forums use the same software. When you join a forum, you will find sticky instructions on how to upload to it in their FAQ section.
Basically there are two ways to get an image into a forum:
- Upload it to the forum server itself. They don't usually like that (but they tolerate it), especially if your image takes up a lot of space.
- Upload it to your own webspace, then put a link to where the picture is in the forum post. That's the preferred way
- Most forums have a limitation of 800 pixels wide x 600 pixels high as a maximum.
