![]() It is not Brightness in the Hue, Saturation, Brightness (HSB) colour model. Photoshop very rarely uses the term Luminosity. Many of Photoshop’s tools, used at face value, operate on a composite of all three channels – not an ideal situation. If you alter a colour image by, say, using the dodging or burning tools, you are actually altering 3 greyscale channels at the same time and unless the relationship between those 3 channels stays exactly the same, there will be a shift of hue or saturation which is of course not the aim of the adjustment. This last point seems quite contradictory what has greyscale conversion got to do with colour adjustments? Well, quite a lot really when you remember that all RGB colour images are comprised of three different ‘channels’ of greyscale information, each of which represents the lightness values of each of the three colours and that it’s the relationship between them which give us the illusion of ‘colour’. What has not been mentioned is exactly why different greyscale conversions give different results, and more importantly, the fact that this principle can be used to make more accurate adjustments to colour images. Differences between the various methods are usually explained in terms of visual appeal or the ability to blend the various colour channels to emulate traditional B+W filters. Much has been written about converting colour to Black and White: we all know that there are a great many different ways to do this, some more effective than others. If I use Export from the File menu the location is correctly pre-selected.Warning – the following is quite advanced (even geeky) and I must assume the reader has a working knowledge of channels, levels, curves, blending modes, tools etc as well as how the main color models work (RGB, Lab, HSB). Note: The Export for Web (K) panel "Export" button never seems to remember the previous export location. I would love to see something similar in Pixelmator Pro.įailing that, having a Automator function for dividing images up would be most welcome. These "commands" could then be used during batch processing, making complex repetitive tasks relatively easy to apply across many images (An example building, saving and applying "commands" can be seen in this YouTube video: ). the actions could be applied again) and/or converted into a "Command" macro. Best of all multiple history items could be selected and re-played (i.e. It had a brilliant History Panel feature which recorded all of the users actions within a session (very like a visible undo/redo activity list). Twenty years or so ago, I would've used Fireworks to do tasks like this. While I have managed to streamline the process by using a layer to hold the slice definitions, the process is still a chore. Images with an odd numbered width lose the left 1px width from the lefthand edge, thus ensure that subsequent slicing results in two identically wide images, that if put back together would appear seamless.Ĭurrently I'm manually processing images using Export for Web and slicing images there. Specifically, I would like to slice images in precisely in half, saving both the left 50% and right 50% with appropriate filenames. ![]() ![]() I'm also looking to batch process a large number of images.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |