Resizing, Cropping, and Trimming

 

For any off-camera photo image printing, editing, and general touch-up, it’s critical that one start by using the original* full-sized photo image file that is, the first possible un-corrupted digital file available from the camera.

An image contained in a JPEG file will display beautifully on any PC, Mac, Tablet, or smart phone screen and, will be automatically resized and/or cropped to fit and adapt to the device’s screen specs and/or the criteria of an application-program currently in control. This is completely transparent; For example: A JPEG file from a new DSLR camera may contain a 6000×4000 canvas**.   Despite a different shape and resolution, the image in this JPEG file displays perfectly on a Galaxy smart-phone’s 5” widescreen screen and also on my PC’s old VGA CRT monitor. …Amazing!

Before adjusting the file size, shape of image, or size of image, one must first ask: Is the image need resizing or does the file itself need to be resized?

File resizing: Sometimes the original JPEG file size is way too big, that is, is comprised of too many digital bytes and bits; typically too big for texting and/or, takes up too much disk space.   Unfortunately, you cannot, repeat, cannot reduce the size of the JPEG file without impacting (corrupting) the image file it contains. There are three ways to downsize a too-big JPEG file. The first is to increase the JPEG files bit compression. Do not lower the quality/compression level more than 50% of the original Image Quality option setting. Any reduction reduces the quality-purity level of the image but keeps the images original size/shape/resolution. Using Photoshop or other editing software, always use “save-as” with a new file-name.   The other ways to reduce file size is the impact the actual image size and/or shape contained within the file.

Resizing Image: Reduction of the image file in terms of pixel resolution is another way to reduce the file size. This is called “down-sampling.” Some photo editing software tools also allow one to increase size (resolution) too. Obviously any resolution increase will the also increase the new file size. Any resolution (ppi) changes do not impact image’s original shape/aspect ratio. Resizing by changing resolution (ppi) is in effect changing the canvas** size of the image. This is pixel manipulation and downsizing by photo-editing software tools is quite efficient, upsizing is not. In Photoshop, use the “image-size” function and specify a smaller (or larger) and “resample”. Again, it’s best to “save-as” with a new file name so you can salvage the “original” file.

For example: An original image inside a big JPEG file may have been 6000×4000 pixels. This would be capable of printing with excellent detail onto a big 20”x 13” canvas (photo-paper) at 300ppi. Cutting the canvas in half by reducing the resolution would result in an image file containing the same image albeit on a smaller canvas at 3000×2000 pixels. The lower resolution image would be limited to print onto a smaller 10”x 7”canvas in order to retain similar quality and detail.

Cropping for Printing: Cropping*** an original image inside a big JPEG file may have been 6000×4000 pixels and trimming is almost always required when preparing a photo file for printing. The shape of the camera’s sensor (as contained in the original photo-file) is more than likely unable to fit onto a standard photo-paper size.

For example: An image inside a smart-phone’s original JPEG file may have been 2500×2000 pixels. It must be cropped to a 2500×1667 image to fit onto a 6” x4” photo-paper. The resolution remains unchanged. The size of the JPEG file will be reduced.

Cropping for Composition: The original image may have a subject that is better viewed if centered or visa-versa. Or, there may be an annoying item on the sides in the image. Cropping (out) sections and/or enlarging a particular area are often desirable with or without cropping for a certain print-paper aspect ration. When done to the extreme and the original is at a high resolution, cropping is a way to substitute for a telephoto lens. I do it often. An original image inside a big JPEG file may have been 6000×4000 pixels. Cropping and trimming impacts the canvas, not the resolution. Image quality is not impacted albeit, cropping effectively is like magnifying the image.

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Trimming: When only minor crops are performed and without any drastic shape changes, it’s called “trimming.”

* Original Full-Size Image File: All digital cameras create a digitized image in its full size and shape that matches the camera physical sensor. That image is digitized and saved within a photo-file that is formatted in an industry-standard way, most often a JPEG type. The first straight out-of-the-camera photo-file is considered the “original full-sized” photo. In reality, the camera’s on-board computer-processing unit likely modifies the original captured image information before it presents the JPEG.   Some of these modifications can be drastic, changing the size, and shape, as well as the image itself. Smart cameras even have post-processing and effects that a user can automatically apply and, this is really replaced the actual original. So, a tip to the wise: Check your camera’s settings.   Also note that professional cameras usually provide “RAW” files containing unformatted bit-by-bit photon data that matches exactly what was recorded in the physical sensor. This is the optimum “original” and can be viewed, edited, and converted into a JPEG file by using the camera manufacturer’s supplied custom software tools.

**  I use “canvas” to put “crop” terminology in perspective. A photographer places an image on a canvas just as an artist paints a creative image onto a real canvas.   The camera’s original canvas “size” is depicted/measured in “pixels” that is, picture-elements rather than in inches/centimeters. The canvas’ “aspect ratio” is the relationship to its horizontal & vertical dimensions. A camera’s canvas size is its starting dimensions conforming to its photocell arrangement in the camera’s sensor and contained in its original output photo-file.

*** Cropping” means a cutout of the canvas. This is akin to taking a scissors to the canvas and cutting out the part that one wishes to preserve.

 

Printing: How Big?

Printing: How Big? Aspect Ratios – Resolution – Size

After having discovered one of your photos looks awesome when shown on your smart-phone screen, consider printing it big and proudly display it on your wall.

Before you commit to printing, mounting, and framing, you best consider just how big can you make the enlargement-print?  Four topics should be considered before determining the maximum printing size that can be derived from your JPEG photo file:

Image Resolution*: In digital photography, a “pixel” is the tiniest element identified in an image. The higher the density (pixels per square inch) the better the detail and visa-versa. Image quality on enlargements is best when its diagonal pixel density exceeds 200 pixels per inch. For example: an advertised 8MP (mega-pixel) DSLR camera typically provides an image with pixels arranged horizontally and vertically in a standard 3:2 aspect-ratio, that is, an image pixel layout of 3600h x 2400v. When printed on a 6”x4” common photo print paper, it would have a diagonal pixel density exceeding 600ppi, way better than needed. However when enlarged/cropped and printed onto standard 20”x16” print paper, the density would drop to about 150ppi which may not be best for hanging on the wall. ….So, I suggest for an 8-12MP camera, one should not consider anything bigger** than 14”x11”.

Standard print-paper sizes: There are numerous photo printing, matting, mounting, and framing shops that will provide custom sizes that allow the shape of the print to match exactly that of the original camera sensor. However, normal printing shops mostly use industry-standard photo-paper, mat/mounting, and frame sizes. Anything other than the common/standard sizes can prove to be expensive. If your camera’s sensor shape/aspect-ratio matches your desired print/enlargement size, you are in luck.   But, more commonly, standard print paper sizes force most to “crop” or stretch/deform the original image to fit onto standard sized paper. In the USA, the most common print paper and frame sizes are: 6”x 4″, 7”x 5”, 10”x 8”, 14”x 11″, 20″x 16”.

Aspect Ratio: The shape (horizontal and vertical arrangement of the pixels) is determined by the camera’s sensor. When printing onto popular/standard sized media, one must consider if and how any cropping is required. Otherwise, you might be disappointed that the print looks so different then you envisioned. For example, quite a few smart-phones produce images shaped in a 4:5 aspect ratio. This is great for a 8×10 standard print but requires cropping for the 4”x 6 print. Some smart-phones output JPEG images in a 16:9 aspect and most always require cropping pre-processing consideration. Don’t be surprised in the results if you leave this to the printer.

Personal Image-Quality Tolerance: After you have determined your maximum print size, the expected image quality may or may not meet your expectations. If you chose the image to print because it looked fantastic when viewed on the 4” LCD screen of your smart-phone, an enlarged printed image may look fuzzy, noisy, blurry, off-colors, and overall dull. Any imperfection resulting from your camera’s tiny sensor will be exposed when enlarged. These are almost always hidden when displayed on a smart-phones tiny LCD screen. **So, assuming an 8-12MP camera can produce a good 11”x 14” print, if tiny sensors ( smart-phones) are involved, one might better be restricted to 8”x 10”.

* WARNING: Image Files produce/saved by smart-phones, point&shoot camera, even DSLRs should be set at their highest resolution, native size-shape, and at its highest “quality.”   The device’s factor default set-up/configuration should be periodically confirmed. Let’s avoid the common occurrence that a user modified these camera parameters and found their camera was taking only thumbnail-sized photos….

 

Color in Photos: Viewing & Printing

The Norm: Millennials mostly view photography on bright screens in smart-phones, tablets, PCs, or even on TVs. These back-lit devices use Red, Green and Blue lights directed onto a dark/blackish background. Most all of the colors that humans can see are created from combinations of these RGB primary lights being transmitted directly to our eyes. When processing/preparing or viewing a photo file for every-day purposes, Android, Windows, and iMac software perform best when operating under its default standard RGB color environment (sRGB.)  JPEG formatted photo files using this same sRGB 8-bit standard are the created by cameras, archived, and used in email and/or posting on web pages (internet.)   The file contains all the photo’s colors pixel-by-pixel in a standardized “sRGB” digitization so that everybody’s display/monitor can produce the same visual color impact as what was taken by the camera, processed and observed by the originator.

Printing: Unfortunately, colors and “punch” are different when printing that JPEG.  Photos that may have been awesome when viewed on your smart-phone sometimes look dull after you printed them.   The reason: When looking at a sheet of white paper, our eyes receive a balanced combination of colored light being reflected off the paper’s surface. White parts of paper reflect most of the white-light provided by the Sun (or by the lights in the room.) If the surface is covered by colored Ink, that part reflects a different color combo. So sRGB values embedded in a photo file must be cross-referenced to something that is “similar” when reflected off a white paper.  A locally attached ink-jet type printer product integrates conversion software that adapts the sRGB color info contained in the JPEG file into its own native ink formulas/pigmentation/dye to best match the photo-paper characteristics. Similarly, outside photo printer shops like Snapfish, Wallgreens, etc. also expect sRGB and JPEG files and tune their hard-copy printing Ink mix accordingly.

COMMERCIAL printing: When supplying press-ready photo or image files to commercial printing operations (for magazines, publishers, and/or printing by external photo/image connoisseurs,) different rules for processing and archiving apply, especially for color.   All printers may not use the identical ink formulations and paper types. Further their sRGB conversion algorithms may differ. Hence a JPEG photo may print in a magazine color-wise different than the photographer viewed on a display. Some printers may require the originator to provide something other than an sRGB JPEG file, specifically a format employing 16-bit color rather using an industrial standard CMYK color gamut, typically TIFF type and extremely large.

CMYK stands for Cyan, Magenta, Yellow, and Key (black). CMYK, or 4-color processing, is the industrial standard for printing. The idea is that white is the natural state of a sheet of print paper. Cyan, magenta and yellow (inks) combine to cover up the white in varying degrees and combinations, producing every possible intermediate color imaginable.

Some photo professionals opt to use special CMYK display monitors and have cameras that can take photos using the CMYK color gamut rather than sRGB.   CMYK 16-bit color photo files, when displayed on normal monitors and tablets produce colors that are quite subdued.

Smart-Phone Cameras

Can my smart-phone take professional-like publishable photos?

Simple answer; yes!

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Macro

Built-in camera technology in the latest iPhone and Android devices has evolved dramatically. Optical image stabilization, dual-pixel focusing, fast lens, fast digital processing and noise control, and even in-camera post processing are impressive features. These newer devices can produce photographs way more substantial than selfies and vacation-trip snapshots. There are millions and millions of these images viewable via social media some that are breathtaking on the small LCD screens.

Professional photographers have been forced to up their game to offer better imagery. So, their equipment has also advanced in technology, and maybe their artistic and digital skills have been forced to improve too. Mastering the artistry of photography understanding bokeh, lighting, special optics, shooting angles, and post-processing craftsmanship separate the masters from the ordinary.

Professional or not, the best equipment (camera) that a photographer needs to capture a prize-winning image is always the one that he has in his hand. Now days, most of us carry a smart-phone 100% of the time. …. So use it.

It does not matter if it was by-accident or you spent hours in your composition and setup.When you see that you have captured a breathtaking photo with your smart-phone camera, I’m sure you want to do more than just texting it to your friends.

Warning: An image may look terrific when viewed on the small-LCD screen of your smart-phone but may or may not look great when viewed on a large PC or tablet screen and may look entirely different when printed on photo-paper.

No matter what your intended final disposition, the first thing is to locate and find the “fill-sized” original image file, likely in a JPEG file. If your smart-phone camera settings were improper, this item has been destroyed. The image viewed may be a modified reduced-size item that has little chance of being publishable. If your smart-phone claims to have an 8MP camera, the deliverable original image file should be 8MP.

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Founded in 2004, T&C DIGITAL PHOTOGRAPHY is staffed by an award-winning New Hampshire based team with over fifty combined years in serious photography.

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Traditional & Creative photography and graphics-design hobbyists create imagery for Portraits, Events, Sports, Product, Architecture, Business, and Motorsports. Imagery combines photography, photojournalism, graphics-design, artistry, and digital expertise.  Photos held in this website bring focus to the natural beauty of the state of New Hampshire, its people, and lifestyle.  Phone us at 603-529-3574 or Contact us at info@tcdigital.net.