Please appreciate that this can be compared to learning to drive. Sure, there are a few details, how to operate the car, safety concerns, and the rules of the road, etc. But you learn it one time, and it's not difficult, anyone can do it. Then it becomes second nature to us, we always know how. So then you can use the skill for the rest of your life, when knowing how will make a huge difference.Images are easy to learn, and safer too.:) We do need to know that digital images are composed of pixels, and that image size is dimensioned in pixels. Not inches, not bytes, but pixels. You just gotta understand this, and it is simple, and this one detail will be repeatedly covered here.So image size is dimensioned in pixels, for example a 4000x3000 pixel image.
Image Resize, Cropping, Resampling, Scaling, and Aspect Ratio for Printing This is about the Least that we must know about using images. For anyone just starting with digital images, or having trouble getting started, here is an review of the first basics we need, about how to USE our digital images, about how to resize them for viewing them on the video screen or for printing. Cropping Photos Without Changing The Aspect Ratio. One of the great things about the Crop Tool is that you can easily crop your photos to common photo sizes like 4x6, 5x7 or 8x10 simply by entering the width and height values into the Options Bar before dragging out your cropping border, or by selecting a preset crop size from the Preset picker.
Megapixels is the total image area (image width x height), so a 4000x3000 pixel image is 4000x3000 = 12 megapixels. Digital images are binary data, meaning, each pixel is just NUMBERS, data describing ONE RGB COLOR for that tiny area, a tiny dot of color, much like one colored tile in a mosaic tile picture. Our brain recognizes the reproduced image in the arrangement of those pixels or tiles. Pixels are all there is in a digital image, so we must think of it that way.
It will make sense when you do (a few more details at ).But relax, we don't need to know much technical depth. To use our digital images properly and skillfully, mostly we only need to realize that pixels do exist, in fact, pixels are all that does exist in our digital images. Primarily, we must understand that our images are in fact dimensioned in pixels, an image is so many pixels wide, and so many in height.
We can see them enlarged above. Just accept it, and think in terms of pixels.:) Then things can proceed properly.There are two general methods to view a digital image: (details of these two vary, see ). Video screens simply show the image at the same size, for example, an 800x600 pixel image will simply be shown at 800x600 pixel size (the video screen size is also dimensioned in pixels).
However images too large for the screen are usually automatically resampled small enough to fit on the screen (then the smaller copy of it is shown).There is often not an advantage of exactly fitting the image shape to the screen shape. Few images are shown full screen. Whatever shape it is, we can view it.Viewing the images on a video screen - The digital camera takes large images, maybe most are generally 10 to 24 megapixels size. But the computer screen size, and also the HDTV screen size, are only about 2 megapixels in size. And cell phone screens are maybe 0.2 megapixels. Sure, you can ignore everything, and simply show the 12 megapixel image as is, but then the video system has to first resample it down to fit on a 2 megapixel or 0.2 megapixel screen size, which takes more time and storage space, slower waiting to access each one.
(Many models of HDTV have a USB port, which easily shows our JPG images from a USB memory stick. But still, 1920x1080 pixels is all the screen can show.) For more than a one time show, you can instead simply properly prepare a copy of the images to be the right size, perhaps to fit the 1920x1080 pixel HDTV screen, which will then become fast and peppy. Hugh images will load slow. Print paper is dimensioned in inches or cm, so printing images 'scales', or spaces the pixels at so many 'pixels per inch' of paper, called dpi printing resolution.
Printing at 300 dpi prints 300 pixels per inch of paper, so that an image size of 3000 pixels covers 10 inches of paper.Printing the image on paper is much more critical, the image shape needs to match the paper shape. If it does not all fit on the paper, some of the image is cropped off and lost. One big issue is that the image SHAPE is often NOT the same SHAPE as the print paper, until we crop it to match. Size is a factor too (number of pixels), and important, but speaking of SHAPE right now (aspect ratio).That's really about it, but you just gotta think about pixels. Doing anything at all with digital images REQUIRES knowing at least this much. It is quite easy, if you let it be (if you will simply think 'pixels'). If your complaint is that the photo lab does not print all of your picture area (cuts off heads, etc), then you really need to learn this easy material.
Aspect Ratio is the shape of things - the shape of the image and the shape of the paper. The rectangular shapes may be long and thin in various degree, or might be more nearly square. There is absolutely nothing fancy or complicated about this. Aspect Ratio is the simple ratio of the two side dimensions. If the 8x10 paper long side is 10 inches and the short side is 8 inches, then the sides are the ratio of 10 to 8, which is 5:4, which is a shape we call aspect ratio. The paper long side is 5/4 = 1.25x the short side.
If the image is 6000x4000 pixels, then the sides are the ratio of 6 to 4, which is 3:2, which is a shape we call aspect ratio. The image long side is 3/2 = 1.5x the short side. If these two shapes don't match, then fitting that image on this paper will be a problem. Shape and Size are different thingsThe shape of the paper is an Aspect Ratio, and the shape of the image is an Aspect Ratio. When the paper shape and the image shapes match (same aspect ratio), then we can enlarge the image size to still exactly fit the paper (which is a very good plan for printing).
To be certain this is clear, an example of the basic concept is that 4x5, 8x10, and 16x20 inch paper are different sizes, but simple arithmetic shows all three are 4:5 ratio shape. So any 4:5 image can be enlarged appropriately to fit any of those paper sizes, all of shape 4:5 (assuming we have sufficient pixels for printing that large). Aspect ratio is a shape, which could be any size.6000x4000 pixels is an image size, and 6x4 inches is a paper size, but the ratio of these width and height dimensions (3:2) is a shape. However paper and images are often not initially the same shape, so printing often first requires that we must crop the image to match the paper shape. If you don't first crop it to fit the paper, the paper shape itself will crop it, sometimes in a surprising way.
For example, a 4x6 image (3:2) is a long and relatively narrow shape, and will not fit 4x5 paper (4:5), which is shorter and relatively wider, a bit closer to square.Image size is adjustable, but Shape can only be cropped. Image shape must fit the photo paper shape.This Crop to fit the paper can be a trivially easy operation (see on next page). We don't need any math skills.
Better photo editors (Adobe Elements for example) should have a simple cropping option to declare the desired paper aspect ratio to be cropped (enter crop as 8x10 shape for example), and then any image crop box we can draw on the image will be this exact shape (meaning shape, not size). We simply mark its crop size to include what we want to include, and it will be that shape (and we can move it around as desired). As for size, our crop result does need to have sufficient pixels to print at about 250 to 300 pixels per inch of paper (e.g., 1000x1500 to 1200x1800 pixels to print 4x6 inches). More detail on next page.
Images from a DSLR camera (and also from 35 mm film) are aspect ratio of 3:2. We can enlarge it to any SIZE, but this means for example that the SHAPE of the 3:2 uncropped images will enlarge to print 4x6 inches, 8x12 inches, 16x20 inches, etc.
Regardless if the image is oriented portrait or landscape (vertical or horizontal), all of these are still SHAPE of 3:2. This shape will print 'as is' on 4x6 paper, but all other paper sizes probably are all different shapes. It is just a way to describe a rectangular shape with numbers, the simple ratio of the lengths of the two sides.There are two similar ways to describe this shape in numbers. For example, for a 6000x4000 pixel image, the ratio of the two sides is 6:4, which we reduce to say 3:2. This is also the ratio of 3/2 = 1.5, or 1.5:1 when one side is compared as 'one'.
Same thing, and we may encounter it either way (typically we say it as 3:2, but we compute with 1.5).A few very common Aspect Ratio numbers are: (more detail on )W:H H/W:1 Aspect Ratio 4:5 1.25:1 4x5, 8x10 inches, 16x20, 20x25 4:3 1.33:1 Most compact cameras, phones, and non-widescreen old movies and monitors 5:7 1.4:1 5x7 inches, 13x18 cm. Also 2.5x3.5 inches wallet size 3:2 1.5:1 4x6 inches, 8x12, 10x15 cm, 35 mm film, and most DSLR cameras 16:9 1.78:1 HDTV format and camcorders, 1920x1080 or 1280x720 pixels. We might call an aspect ratio as being either 3:2 or 2:3.
These are the same paper 'shape', just depending on which way the image is rotated. The usual 'correct' ratio is when the image is viewed in its proper upright orientation, then aspect ratio is Width:Height, whichever that is. We all understand it either way, but by convention, camera sensors (images yet untaken) are generally named landscape orientation (largest first, 3:2 or 4:3 or 16:9 or 5:4), but print paper purchased still blank is normally named as portrait orientation (smaller first, 4x6 or 5x7 or 8x10 or 8.5x11). Obviously the paper can be rotated either way for printing, and we match that by specifying either Portrait or Landscape orientation in our printer driver options, which then simply rotates the image correctly for that paper orientation (load the paper the right way).Aspect ratio is only critical when matching an image shape to one printed paper shape, or maybe to full screen monitor shape.
Only one ratio fits another shape. And since many shapes exist, no one ratio number is very important, except for your current match, when it is all important.Size and Shape are different things. Cropping can change the image shape (to fit the paper shape). When we only enlarge the image size, it stays the same shape.
A 4:5 image can fit 4x5 or 8x10 paper, but is not the shape of 4x6 or 5x7 paper.If you use a 3:2 DSLR (or 35 mm film) and only print 6x4 prints, these are the same shape, so you may never realize there is any problem. But all other combinations will see a problem.Photo images from a compact or phone camera are 4:3 shape (long side is 1.33x the short side, 4 to 3 ratio).
However, 4:3 is NOT a common paper shape. Some photo printing labs offer 4x5.33 inch prints which do fit them (if you specify it). And 6x8 or 9x12 inch paper may be available a few places. Phone and compact camera images are typically 4:3, which will Not fit 4x6, 5x7, or 8x10 inch print paper without cropping.DSLR images typically are 3:2, and Will fit 4x6 inch paper.But neither 4:3 or 3:2 will fit 5x7 or 8x10 inch paper without cropping.This definitely IS something to think about.
Letting the automation just crop it with the paper edges can be a surprise, perhaps with cut off heads, etc.It is very easy to crop them correctly yourself first, solving all problems, achieving your own goals.A rough visual guide in the camera viewfinder, for estimating the planned crop lines for future printing. Note that the cropping need not be centered, it could be all at one side or the other, positioned as needed to frame the important view.
And note that if cropping it smaller than this (retaining same ratio), both width and height will be reduced.Cropping serves two purposes, for the best appearance, and to fit the print paper.In general, cropping a little tighter often pictorially improves many images anyway (removes empty, uninteresting, or distracting surroundings, and makes the subject a bit larger). Often it can be a big plus. Kodak's standard tips for always emphasized 'Get Closer'.
Cropping tighter later can correct to serve the same purpose (if it leaves sufficient pixels remaining), and cropping is usually a necessary step for printing anyway. Opinions will always vary about specific details, but cropping is very easy to do. We can crop to paper shape any way we want, so why not give a little thought to improving your prints too? The biggest benefit is to first give it a seconds thought in the viewfinder. Slightly changing camera position (to choose background) can be a big help sometimes. The purpose of the viewfinder is to examine your image BEFORE you click the shutter button. Most printing labs (where we send photo files to be printed) set up their machines to fill all of the paper.
Normally they won't underfill the paper to leave white space, they will instead cut something off the image if necessary. If you order 5x7, you will get 5x7, but you may not get all of your image. This means if you print your images without first preparing them (cropping them to the correct shape to fit the paper ordered), you may see surprises about parts of your image cut off, not showing in the final print.This is nothing new with digital cameras, film was always the same thing. The film negative has a shape too, generally simply not the same shape as the print paper.
However back then, there was a human operator watching and controlling and making decisions and adjusting things for film images. Digital machines are automatic (inexpensive prints), but digital does make it easy for us to crop it right first. Many online photo printing web sites offer a crop tool there online, and also ordering sometimes warns when our image is not the same size as the selected paper. And some processors offer an option to 'Print Full Image', meaning, they won't crop anything off, but will instead leave blank white space (borders) where it doesn't fit the paper. You can trim the paper smaller then.But generally, the paper shape itself is going to crop it, and a different shape simply will not fit.
Something has to go. And of course the point is that when we crop it ourself, then we see it, and we can judge and decide ourselves which portion of the image is to be cropped away. Probably we can choose to crop the edge opposite from the head we want to save.:)Cropping to Fit Image Aspect Ratio to PaperSize and shape are very different things. We cannot fully print a 4x6 image on 4x5 paper. The purpose of this next aspect ratio calculator is to help give an idea of the crop for the aspect ratio of the paper you want it to fit.
The calculator is a minor thing (see details in Cropping section on for the actual procedure), but perhaps the numbers can make the major point that cropping to fit the paper shape is usually very necessary. The paper is usually NOT the same shape as the image, so we can choose to fit the long side to the paper, or to fit the short side to the paper.
I am trying to emphasize the difference between SHAPE vs SIZE, but both are important. The point of the calculator is to show that image shape and paper shape are often NOT the same shape (so we must crop the image shape to fit the paper). Most camera images won't fit the paper without cropping. Results are better if we crop it ourself, for our choice about what is to be cropped off.An Unusual Crop CalculatorThis is NOT meant to be a working tool. It will provide an accurate answer about the result, but instead it's an overdone effort for illustrative purposes, just to show the concept involved, to show the problem we always need to solve when printing. Better maybe, the Summary chart probably is more clear, and should be informative. The image and the paper of course need to be the same shape, but usually are not, not until we correct by cropping the image to match the paper shape.
In regular use, your photo editors crop and resample tools should be very adequate, if you understand the situation and know your goal (next page).Here, specify your image shape and your paper shape (numbers only). Calculations assume borderless printing.
The calculator just computes the precise image numbers with shape which fit the paper. Another option is to enter 'Other' for paper, and then enter any actual paper dimensions. But the shapes of the image and paper do need to match fairly closely.The Summary Chart assumption is that the print shop will fill the specified paper size.
The percent error is the cropped off percentage of the image when the paper is filled. The words End or Width here refer simply to the cropped long End or the narrow paper Width, ignoring Portrait or Landscape Orientation.But if only one dimension is fitted leaving blank space on the other side, the same percentage applies to the blank space. The exact percentage numbers are not the point here.
They are what they are, and any difference is not good. We know of course that a 4x6 image simply will not fit on 4x5 paper. And images and paper are often not the same shape, which of course means the image must be cropped to be the same shape as the paper. This is just trying to emphasize that point here.
We have good tools making this crop very easy to do, and it's an extremely important skill to learn. The point is, if you crop it yourself first, then how it turns out is your own choice. More how-to about cropping to aspect ratio on.Just a few pixels is normally no big deal, but otherwise, we of course should choose the best way to crop the image to the correct SHAPE first (to match the paper shape), and after that (if image is too large), then we might resample the image SIZE to print at about 300 dpi on this paper. I worry that novices not yet familiar with images may miss the point. Do realize that cropping to the paper shape is an extremely important issue when printing an image.Aspect ratio is just the simple ratio of the two sides.
6000x4000 pixels is 6000:4000 = 3:2 = 1.5:1 ratio. This ratio represents the Shape, the simple ratio of the sides. Like all math fractions, we normally reduce the 6000:4000 to express it as the ratio 3:2, using the greatest common divisor method discovered by Euclid, 4th century B.C. (GCD is 2000 in this case).
Math does like exact numbers, and if our image had been 5998x4000 pixels, then greatest common divisor is 2, so reduction comes out 2999:2000, not exactly 3:2, and not as easily recognized (the calculator may show rounded minor differences).NOTES:. The photo editor's crop and resample tools will be your most useful tool. Crop to the print shape, and then resample to the print size and resolution (described on ). Not all programs offer an easy crop to print paper shape. Adobe does (Elements, Photoshop and ACR).
Gimp and PaintShop Pro do, most better editors do. It's a Crop or Marquee Tool option to specify a crop aspect ratio, and then any crop you mark matches the specified paper shape. It's an essential tool for printing.
![Aspect Aspect](https://vignette.wikia.nocookie.net/finalfantasy/images/8/8c/FFRK_Whisperweed_FFV.png/revision/latest/fixed-aspect-ratio-down/width/480/height/480?cb=20171016071510&fill=transparent)
Yes, resample tools typically provide an option to NOT preserve image proportions. That way, we could resample 4x5 to be 4x6, or 3:2 to be 8x10. However, that distorts the image, stretching or shrinking one dimension instead of changing both dimensions equally. Circles would become ovals for example. People could become tall and thin, or short and wide. For resampling photos, surely you always want resampling to preserve, retain, maintain, or constrain image proportions (however the editor words it, which should be default).
Instead, here we speak of CROPPING the image to match the paper shape.Image SizeSo image Shape is important, and also, image Size is important. We can crop the shape, and resample the size (to be smaller - resampling larger does not add needed detail).
Discussed on next page, but for printing goals, the necessary procedure should be to first crop image to match the paper shape, and then resample smaller to produce image size of about 300 dpi. That means for example, to print a 6x4 inch print at the ideal 300 dpi resolution computes. (6 inches x 300 dpi) x (4 inches x 300 dpi) = 1800 x 1200 pixels needed (2.16 megapixels)Sufficient pixels to print at 250 to 300 dpi is optimum to print photo images. More pixels really cannot help the printer, but very much less is detrimental to quality. This is very simple, but it is essential to know and keep track of. This simple little calculation will show the image size needed for optimum photo printing. This calculation is so simple, and is one thing you really need to know, and it should be second nature to you, to be considered when printing any image.Image Size Goal fordesired Print Size.
Scale it - The third way to resize is to scale your existing image for print paper. Scaling changes ONLY the dpi number, which is just a number. Scaling does NOT change the image pixels or the image shape in any way (no resample, no crop), so scaling does Not affect the video screen at all (the monitor does not use dpi). Scaling works when printing images on paper. Its only action is to change the single number for dpi (ppi), which is an arbitrary number that is simply stored separately in the image file. It is only used by the printer, and it only changes the size this image will print on paper (at so many pixels per inch of paper.
The inches are on paper). The number has no effect on images on the computer screen (video just shows pixels, which does not use dpi or inches).The camera has no clue what size you might print the image, if at all, so it just makes up some dpi number (it does not affect the pixels). We fix it before printing (called scaling, which simply edits the dpi number).
Word definition: One use of the word 'scale' is as a graduated measurement, like the scale of a map, and scaling is creating a proportionate size or extent. 100 miles of a map drawn at 20 miles per inch will cover 5 inches of paper. In photo printing, scale is pixel distribution relative to the paper dimension.Scaling is computing that 3000 pixels printed at 300 pixels per inch will scale to cover 3000/300 = 10 inches of paper. Setting the 300 dpi number 'scales' the 3000 pixels to print 10 inches on paper. The dpi number fresh out of the camera might say 72 dpi, 180 dpi, 240 dpi, 300 dpi, etc, but which was arbitrary, it simply does not matter what it is.
The camera has no clue what size we will print it, and this number called dpi has absolutely no meaning until we actually do this proper scaling for the one specific future printing purpose.So scaling stretches the image on the paper, without changing any actual pixels. It changes only the actual dpi number (printing resolution, the spacing of the pixels on paper), which changes only the number of inches the same image pixels will fill on paper (spaced at so many pixels per inch). Because, the image simply prints larger with a smaller dpi number (wider pixel spacing, fewer pixels per inch), or prints smaller with a larger dpi number.Your PC Print menu normally offers this with its Fit To Paper choice, but again, it changes only printed size, and NOT shape.Cropping or Resampling are NOT reversible operations (pixels do get changed), however Scaling is completely reversible, it merely changes the separate dpi number that will be used to adjust pixel spacing (resolution) when printing on paper.