29

I can't believe no one suggested this yet: Just use the rectangular marquee to select what you want to crop down to, and COPY it to your clipboard. Then delete the entire layer and PASTE what you copied to a new layer. This is especially useful if the layer you're cropping is larger than the canvas, in which case the select-inverse technique is messy.


18

Use a layer mask. Tutorials galore exist on the topic already, eg: http://helpx.adobe.com/photoshop/using/masking-layers.html Straight from Adobe: You can add a mask to a layer and use the mask to hide portions of the layer and reveal the layers below. Masking layers is a valuable compositing technique for combining multiple photos into a single image or ...


15

Here's a solution using python and opencv: This will crop all the faces it finds in the jpeg photos in whatever folder you run it in, with the padding specified by the left, right, top, bottom variables: import cv2 import sys import glob cascPath = "haarcascade_frontalface_default.xml" # Create the haar cascade faceCascade = cv2.CascadeClassifier(...


14

You can also select the area you want to crop to with the rectangular marquee tool, invert your selection, then delete the now selected outside area. This is different from the layer mask in that it completely deletes the surrounding area, whereas the mask makes the surrounding area invisible.


14

You know when to stop when you are satisfied with the result. There's nothing more to it. It is your image, your feelings, your point of view, your way of expressing yourself. I don't think there's a definite answer, because this is very subjective. Also, the "rules" you mentioned are not really rules. They're more like guidelines. You need to know them (...


12

Photoshop's Batch command can do this. You would essentially 'record' yourself performing the crop etc once, then run the recording on all the files you want. If you want to automatically resize the smaller images you would have to do a little scripting. Irfanview also has a comprehensive image batch processor but might require a bit of experimentation to ...


11

Your 200mm will still be a 200mm. It will project the same image on the sensor. In DX mode, all that will happen is the camera will throw away the outer areas of that captured image and retain what would have fallen on a DX sensor. This is something you can do yourself in post-processing, so I don't think there is much benefit (apart from smaller file ...


11

Note that you can crop JPEG images without having to reencode them if you use tools that work with the JPEG format, such as jpegcrops, jpegcrop, or jpegtran - these tools perform lossless operations on JPEG files, including cropping, concatenation, and certain transformations (e.g. 90-degree rotation) by working with the underlying DCT data (as opposed to ...


10

ImageMagick let's you run commands in a windows command window. You need to be comfortable with creating Dos batch files. For an example see the last post in this discussion: http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=21112 Relevant example from this forum post: @echo off cd C:\Users\user\Desktop\New\New folder convert *.jpg -...


9

When shooting JPEG you usually have to option to select the size and quality of your image. For instance with Nikon cameras you can select Large and Fine. This option will give you the maximum resolution. This is also the resolution of the RAW file so you will not gain any resolution if you shooting at the maximum JPEG quality. Shooting RAW will give you ...


8

First you want to start with the best selection possible. Here you have some choices. Select using lasso, quick select (not ideal unless you want to do lots of adjusting). If you do use these, once you've made the best selection you can, click on the Refine Edge button in the tool bar and use the sliders to inteligently adjust your selection. Near the ...


8

Question 1: Does it look good at that size? Your image will look good because most people will only look at it from afar. If it is at a trade show and depending on where exactly it is, no one may be able to get close to the image. Much more about this can be read here: How do I generate high quality prints with an ink jet printer? Using Patrick Hurley's ...


8

Aspect ratio is only critical when matching to one printed paper size, 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. Otherwise, if not matching to any specific shape, then it's entirely your choice, how ...


7

Lightroom gives some good cropping tools, IMO. Press "R" or go to the Develop module and click the crop tool below the histogram (though it sounds like you know that part). To set the aspect ratio, in the Crop & Straighten tool area is an "Aspect" row, and from a drop-down you can select predefined aspect ratios, create a custom aspect ratio, or just ...


7

First I thought you wanted batch resize, which many programs can do. But then I realized you want to do a combination of resizing and cropping, and you want the computer to calculate how to best cut out 600x600 pixels from the image dynamically. It is because it is not a "one true solution" kind of task, as it is usually human judgement call, how to crop ...


7

I just discovered a way to do this. I'm using RawTherapee 4.2, but from your screenshot, I think this feature is in the version you used, too. It's in the toolbar just to the top right of the image. From my system: The blue, green, red, and gray squares let you preview individual color or luminosity channels — they're toggles you can click on. To the left ...


6

There are enough programs, even free, which do what you want. Usually, these are picture managers which allow you to select the files/directories to process and what processing/conversion to do for them. For example the procedure for the XnView (freeware) is as following: select the desired files directories. go to Tools > Batch Processing... on the ...


6

Adjusting the focal length of your lens (ie, optical "zooming") will impact the depth of field of your image. This will change how much of the scene is in focus. It will also subtly change aspect of the distortion of the image in order to project it on to a rectangular surface as lenses don't quite perfectly project their image and the exact variations ...


6

Every image format (JPEG, PNG, TIFF, etc.) that I know of can only represent rectangular images. This means that unless you define your own image format, this simply cannot be done. The only thing you can do is to work with transparency. Even though the image itself will still be rectangular, if only a circular portion of it is opaque, it will look like a ...


5

If you like programing, you can use Python (computer language) and an excellent library know has PIL to crop, re-size, plot histograms, get individual pixel vales, etc... on a programmatic level. Thus you can easily write a simple script to find all images in a folder and perform the operation. This code should do exactly what you want and should process a ...


5

There are a couple of ways of centring a crop in Lightroom. If you hold down Alt (Windows) / Option (Mac) as you drag a crop handle you get a symmetrical crop around the centre of the image. To centre a crop on a specific point other than the centre of the image, go into Crop mode then keep pressing O to toggle between the various crop overlays. If you want ...


5

Irfanview. Press B to go to Batch conversion, add your images, click "advanced" and tick "Auto crop borders". Works a treat.


5

There are a few ways to do that. With the selection tool: First select your subject as usual (around the "clear image" part) Enlarge your selection by half the width of your "fuzzy border" with Select->Grow (so if you want, let's say 50 pixels of fuzzy, grow the selection of 25 pixels) Smooth the selection with Select->Feather for the same amount of pixels ...


5

With a ideal 2x teleconverter, you will be 2 f-stops down from what the lens is set to. Think about the basic physics and this should be clear. A 2x teleconverter makes the dimension of anything in the image 2x larger. Something that would result in a 1x1 mm square with the bare lens results in a 2x2 mm square with the teleconverter. That 2x2 mm square ...


5

"100% crop" means a crop of the image at 100% enlargement (i.e. not scaled down to fit on the screen). I agree the term is totally misleading - it sounds like a 50% crop should be half an image, so 100% crop should be the whole thing! It's a term that's widely used unfortunately, I prefer the term "actual pixels" so I use that wherever possible in the hope ...


5

As the sensor is 3:2 that's the natural size to choose when shooting. Cropping can be done in post, where you have any option you want. If you crop when you shoot you waste pixels. In my experience it is best to crop later if possible and to capture as much as possible - sometimes you find a composition ( framing ) in post you were not expecting when you ...


5

I'm assuming you probably used a compact type camera with an image shape of 4:3 (long side of image is 4/3 longer than short side, which describes a "shape"). But a 6x4 print is the shape 3:2... simply not the same shape. So not all of the image will fit on the paper. Images generally have to be cropped first to fit the desired paper shape. And most print ...


5

From an idealized perspective, cropping and enlarging is functionally identical to zooming. In reality, of course, you lose pixels, and you probably lose real resolution as well since you are demanding more from the lens and camera system by looking more closely. Since you are discarding the edges of the frame, optical flaws — including lens distortions will ...


5

When you crop an image you inevitably lose resolution, as you delete parts of the recorded image to better frame the remaining. This will become more noticeable when you enlarge the resulting image on a large screen or print, depending on the final resolution. But beside that, you may lose some more detail due to a number of factors: saving the jpeg with ...


5

How much cropping did you do, and what is your definition of "a lot of resolution?" The answer is always "doing everything in raw is better," always, simply by definition. It is never better to use a compressed image if you can use an uncompressed image, simple as that. However, whether the difference is perceptible depends on what you're doing. At my ...


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