When compositing several images in a single document I often find that a portion of a layer (or portions of multiple layers) will end up being positioned outside of the visible image area. Photoshop, of course, is still keeping track of this information (in case I choose to reposition the layer), but when I’m certain that I will no longer need it, I can choose Select > All and then Image > Crop. This eliminates unnecessary information outside or beyond the visible image area and will typically help to keep my file size more manageable.
Note: when working with Smart Objects, Photoshop will still keep the additional information, regardless of whether or not you crop the document.
In this episode of The Complete Picture (Video Tutorial – How to Optimize Lightroom 5), Julieanne shares several suggestions for hardware, software, and preferences to help optimize the performance of Lightroom. Keeping these tips in mind when setting up a new system or refining your current system will help speed up Lightroom and make you more productive.
Don’t forget that in Lightroom you aren’t committing to a specific output size when cropping. Instead, you specify the actual number of pixels that are going to be created when you use the Export feature or one of the Output modules (Slideshow, Print or Web) to create a raster (pixel) based image.
While using the Crop tool, you can select from the list of default/preset aspect ratios, or choose Enter Custom from the list and create your own. Lightroom will save the last 5 custom aspect ratios entered.
To create custom New File presets, enter the desired settings into the New dialog and then click the Save Preset button. Your custom settings will appear near the top of the list. (Be sure to name them well so that you know what they are – for example 12 x 12 in at 300 ppi 8 bit RGB).
To use the dimensions of one open image to crop another open image, select the open document with the desired crop (width, height, and resolution) and click the “front image” button in the Options bar. This will enter the height, width and resolution for the document in the Options bar. Then, switch to the document that needs to be cropped and drag out the crop tool. The aspect ration will be constrained while dragging the crop and, when applied, the image will be resized to the desired width, height and resolution.
When using the Image Size dialog box in Photoshop, there are several different resampling options including those used most by photographers — Bicubic Sharper, Bicubic, and Bicubic Smoother. These different options have an impact on the perceived sharpness & smoothness of the resulting image. When changing image size relatively small amounts (say scaling up or down less than 10%), it may not be necessary to change the default setting of (Bicubic), but when making large changesbe certain to choose the appropriate option for the maximum quality. For example, if you have a high resolution scan and need a low resolution version to place on the web, make sure to use the Bicubic Sharper option. If you have a low resolution capture from your phone and want to resize it to print as a poster, use the Bicubic Smoother option.
If you are going to need to resize a photograph significantly larger or smaller than it was originally captured, it is better (in theory) to use the Crop tool and the Workflow options in Adobe Camera Raw to interpolate up (resample) the photo as oppose to opening the file in Photoshop and then using the Image Size command to interpolate. This is because ACR does its resampling adaptively, based on the difference in size between the original image size (e.g., 5616) and the target image size (e.g., 2096). So, although there will be slight differences between the two images, (one from ACR, the other from PS) in many cases, it would be very hard to see the difference to the naked eye. The main difference, then, in practice, is the convenience and the workflow. (Thank you Eric Chan for this information!)
When a layer is larger than the canvas size (maybe you dropped a larger file into a smaller composite), Photoshop keeps track of the information beyond the visible canvas. This provides added flexibility if the image needs to be repositioned. However, when working with really large files (for example when I create my digital illustrations, each layer is 24 x 24 inches at 300 ppi and the files often reach greater than 1.5GB very quickly). In order to keep my file size down, as soon as I am certain that I will not change my mind and reposition the image, I choose Select > All and then Image > Crop. This crops any extraneous information beyond the visible canvas size (which is typically significant for my images as I photograph in a 2:3 aspect ratio but my final images are 1:1). Of course you do loose some flexibility so make sure that you are happy with each layer’s position before cropping!
When compositing several images into one document I often find that a portion of a layer will end up being positioned outside of the visible image area. Photoshop, of course, is still keeping track of this information (in case I choose to reposition the layer), but when I’m certain that I will no longer need it, I will choose Select > All and then Image > Crop. This eliminates unnecessary information outside or beyond the visible image area and will typically help to keep my file size more manageable