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.


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 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 (...


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 ...


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

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

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

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 ...


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

I found this question 9 years after the fact, but I just liked how many things the original photo said to me. It's a really good example of "What do you want it to say?" so I thought I'd have a go at making it "say" some different things. No right, no wrong... Darkness, gothic, trapped, escape Light, hope, home, play Girl meets ... ball Why are all ...


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

"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

Thanks to @Ryan's answer which I adapted 5 years ago, I automated most of my first desk job. It's now the open source package autocrop on PyPI, and can be used from your terminal, or through a Python API. If you have Python installed, install it via pip install autocrop and use it thusly from the command line: autocrop -i pics -o crop -r reject -w 400 -H ...


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 ...


5

It's possible the lens is miscommunicating with your camera. If the camera's Auto DX crop setting (under Shooting Menu > Image area) is set to "On", and if somehow your camera is interpreting the lens as a crop lens, then it will automatically crop the center of the sensor when it takes images, and will draw the DX crop reticle you see in the viewfinder. ...


5

I just thought I ought to add what finally happened to that crop/composition. Caleb's comment made me think - "What are you trying to convey with this image?" Answer - Big flower! In. Your. Face. So I went with the tight crop & sent something approximating the one near the end of my original question to the client's phone. For some reason we had our ...


5

Short answer Bright, sharp primes, when paired with high-resolution sensors, can be a viable alternative to slower, variable aperture zoom lenses and enable effective zooming. Constant aperture lenses, if you can afford the price and bulk, are the better choice. The exact impact on resolution and light capture will depend on the exact lenses being compared. ...


4

View>Snap Or Shift+Command+; (on Mac), Shift+Ctrl+; (on PC)


4

I would never shoot to the aspect ratio of a monitor. Using one of my photographs as a backdrop is an afterthought, not a deciding a factor in how to frame a shot, and that would be the only reason I'd ever want a photo in that aspect ratio. Given that, I would always crop and scale in post. However, here's the basic reasoning I would have given your options....


4

When viewing a 100% crop you are viewing each pixel at 100% size. In other words each pixel in the photo gets an entire pixel on your computer screen or other viewing screen. When an entire high resolution photo is viewed on most computer monitors or other smaller screens the image must be scaled down to fit. There isn't a standard term for this because ...


4

Disclaimer: Im the developer of this tool. You can use Face Crop Jet to detect and crop faces from photos in Bulk.Images of any Format or Size is supported.Faces will be detected and cropped automatically(not just the face,a profile picture for id cards). The software can be downloaded from http://www.facecropjet.com


4

With the current firmware of the D3200 you can't crop the image arbitrarily, you can however trim to the aspects (3:2, 4:3, 5:4, 16:9 and 1:1). This can only be done to sizes in certain steps only. You can access this function through the retouch menu and then jump to the function "Trim". I would strongly advise against using this method to crop the photo. ...


4

This will probably require a bit of scripting or programming. Read up on the Circle Hough Transform. Basically, it detects circles in an image. While the maths are quite complicated, you can probably find a decent library in a language that abstracts away a lot of the complexity. For instance, checkout the OpenCV (Open Computer Vision) library, which has C, ...


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