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Does anybody using LUTs in their post?
Tulack wrote: Real interesting on the video colouring. $99 was just a bit too much for me, particularly when I saw a photographer mentioning heavy-handed. Nevertheless, intriguing. May 26 14 09:16 pm Link Jun 20 14 11:04 am Link Jun 27 14 12:56 am Link Aug 08 14 08:45 am Link Aug 18 14 04:26 pm Link I can't wait for adobe to buy this out and integrate it the way they did with cool edit. Can't afford it but if it was part of CC, it makes us all happy. Aug 18 14 09:52 pm Link so, i just tried the demo and after downloading it, both chrome and AVG complained that it contains a virus. The author might want to look into that. Aug 20 14 06:55 pm Link Aug 21 14 11:00 am Link This precision and falloff effect is interesting, Tulack. Some time ago I was playing with a 'color deconvolution' filter used in forensics. I thought it might be good for pulling hair masks by forcing the color to black or white. (obviously magenta against cyan is an easier case) http://www.digitalartform.com/archives/ … nvolu.html Does your software have any applicability to this? Aug 21 14 11:34 am Link Aug 22 14 12:25 am Link Tulack wrote: Sort of, I guess. Aug 22 14 08:29 am Link NothingIsRealButTheGirl wrote: I'd guess that it should be able to do that very easily by boosting the lightness of certain colors and crushing it on others. This is one of the first things I plan to try in the demo once the fake(?) virus warnings are resolved. If you're a braver man than I am, you could give it a try in the demo, yourself. Aug 22 14 11:38 am Link Aug 23 14 12:05 am Link Aug 25 14 11:43 am Link Tulack wrote: I don't have an example handy but if the edges are good I don't mind (if necessary) using different parameters in pieces all around the outline and combining it myself into one mask later, rather than having a single solution work for the whole image. Aug 25 14 11:48 am Link Aug 25 14 12:41 pm Link Sep 04 14 03:14 am Link This program is kind of an interesting approach to color correction. I've been using it to shift selective problem areas. You can hover over the area of the pic you need to fix, and it shows you on the grid where the corresponding point is, which can then be modified using a very visually oriented interface, and it's quite fast about it. I like that it retains the last setting when loading a new file (great when working on sequential groups of pics). Very well done, IMO Sep 08 14 10:14 pm Link Anyone worth their salt would. It's essential to digital image processing. Sep 08 14 10:16 pm Link I think you people are confusing Look up tables with Grading. Yes you can do that with a LUT..but really when someone refers to a LUT it's the LOG to Lin transformation correction as dictated by the camera space..silly retouchers And yes you can Grade a Log with a curve to give it a look. Tulack wrote: Sep 08 14 10:18 pm Link Sep 08 14 11:16 pm Link Nathanfx wrote: You are confusing 1D and 3D LUTs. Sep 08 14 11:26 pm Link Sep 20 14 01:53 pm Link Nathanfx wrote: That's not the case at all. a LUT is a very general thing -- it just transforms one set of colours to another. A Log to Lin LUT is just one kind (and they can come in both 2D and 3D varieties). There are many other colour corrections that are packaged into LUTs (most of them are 3D LUTs in the visual effects business these days). Sep 21 14 08:51 am Link Sep 30 14 10:31 am Link Tulack wrote: I took a quick look. Sep 30 14 11:11 am Link Sep 30 14 11:19 am Link What is a LUT? A LUT is a 'look-up table.' We often want to change certain values into certain other values. A 1-stop neutral density filter, for example, takes a given amount of light and cuts it in half. In fact, that is the rule that governs the behavior of a 1-stop ND filter: whatever light you receive, block half of it and pass the rest along. Often we can describe the rules we want to create as mathematical functions, or equations. An equation that cuts whatever it receives in half might be written as follows: f(x) = 0.5 * x. If you understand that equation -- great. If you don't understand it, don't worry. All you really need to know is that it's a mathematical function -- a rule for converting certain inputs into certain outputs, reliably, and in the same way every time. Programmers and mathematicians love functions because they are compact ways of describing how to change one thing into another thing. But here's the thing: it isn't always possible or worthwhile to come up with a math rule for describing a function. Sometimes you just want to draw the curve that does what you need. You've probably used curves in Adobe Photoshop without knowing their equations. It's possible that even Photoshop doesn't know the equations. How can Photoshop itself not know the equations? Because there might not be any. In 8-bit images there are only 256 possible brightness values that can be used as inputs, and 256 possible brightness values they can become. That's a small number. The number is so small, in fact, that you can write them all down in a table. If you know what you'd like each of the 256 input values to become you could add a second column to your table and write down all 256 answers. Then later, when you are given an input that needs to be transformed, you could just look up the answer in your two-column table. You could call the table you use for looking things up a lookup table, or a LUT, to abbreviate it. In fact, that's exactly what A LUT is: an exhaustive list of inputs and outputs. What about 16-bit lookup tables? Those would have 2^16 = 65536 inputs and outputs. That's pretty big. Too big to conveniently write down. Maybe you could write down every 10th or every 100th table entry and guestimate the inbetween values by pretending straight lines connect your sparse dots. That would work. It would be one way to do it, any way. So far, so good, but up to this point we've been talking about 1D curves and 1D LUTs. In Photoshop we can do quite a bit of color manipulation with three 1D LUTs, one each for R, G and B information. SO what exactly is a 3D LUT? A 3D LUT isn't just another way of talking about three 1D LUT's. It's something else, entirely. In math we could call it a function in 3 variables, some function f(r,g,b). Again, don't worry too much about that. Just consider this question: How using three 1D LUTs (and no masking -- just curves) can you make a rule that all red values in an image should be cut in half, but all yellow values must remain unchanged? Can you think of a way? Remember, in RGB systems yellow is made from red and green, so how using curves alone, and no masks or selections, can you change the reds in an image without changing the yellows? The answer is you can't. Not without using a 3D LUT. A 3D LUT is a way of combining the red, green and blue rules into one 'super rule' that says things like, let red get darker, but only if green in the same pixel is not too high. If tf that sounds complicated to do, and maybe like involves some sort of computer logic programming, don't worry. Using this software you'll soon be doing exactly that sort of color work using an intuitive GUI that you should find both and simple to use and understand. Before we get into any any details of the software, lets take a look at a simple example... We start by thinking of color as a cube-shaped space. We change one color into another by moving a point from one place in the cube to another place. High bit depth color has too many possible values to literally write down into a lookup table, and 3D adds even more complexity, so we think of our color space as a simple cube of, say, 16 x 16x 16 voxels. We are going to move the corners of these voxels around. Watch what happens... Sep 30 14 11:48 am Link If you find any of that useful you are welcome to it ^ I wrote it just now. Sep 30 14 11:49 am Link Sep 30 14 01:49 pm Link Nov 13 14 02:44 am Link Nov 21 14 01:56 pm Link Nov 22 14 02:26 pm Link Dec 03 14 09:45 am Link Dec 03 14 01:00 pm Link Dec 06 14 03:46 pm Link Dec 10 14 05:00 pm Link Dec 21 14 08:58 pm Link I understand the amount of effort, hard work and innovation put into this, I also understand that nothing is free and that you should be compensated accordingly. Is there a way to have some sort of two tier price structure? I am a photographer, I might be interested only in this aspect of the program, I have no use for video support which, understandably, one of the factors behind the price increase. @ $199 , it is currently out of my league, if it is priced only for Photoshop, I might be able to afford it. Back to the fun stuff, I have a question: In one of your early demo videos, you showed a girl with RED shirt setting in a garden, the demo showed how to change the color from red to blue, however, this will also change the color of her lips, the mask demo covered wide varieties of masks, however, the ability to isolate the effect to just one physical region is not there, like, how to limit the change to just the shirt but not the lips if the hue, saturation and luminosity of both are the same. Added: It would be nice feature to be able to select a region to apply any change or effect to, maybe, using a rectangular marque to define physical area to limit or apply mask to, this might help in situation like the girl in RED shirt example. Jan 02 15 10:39 am Link Jan 02 15 04:21 pm Link |