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Color Correction and Q&A

Lesson 7 from: Color Management

Eddie Tapp

Color Correction and Q&A

Lesson 7 from: Color Management

Eddie Tapp

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Lesson Info

7. Color Correction and Q&A

Lesson Info

Color Correction and Q&A

A few things that I want to mention that I failed to mention earlier and what is when you're creating a profile patches to read, of course, as we talked about, you don't want to have any color space involved and adobe photo shop cs six you can no longer go to the print module and used no color management that is no longer available. However, you can go to an adobe website and download an application called adobe color printer utility, and this will allow you to create keep patch in front the patches without any color interference so there's a link to that that should be that I have sent in so that should be in the chat room is my fact I believe it is in the chat room, so there's a link in the chat room to download the adobe color printer utility for those of you geeks that really have to go into print your own patches and the other thing is looking in light room that great question about perceptual a relative color metric when we go to the print module in light room, of course that is ...

an option and the color management module choose perceptual are relative color metric it's right here, I think the question had to do when we're exporting two s rgb and I didn't get the answer to that, but my assumption is that probably going to be perceptual just to be on the safe side in that respect, ok? Photoshopped dirt that's what I call this what is that? Digital imaging rescue techniques? These techniques are only done in photo shop. Uh, because of what you're going to say, I'm first going to bring up an image and show you what are considered to be one of the most important techniques for you to learn in this particular sessions what I call the ninety percent method of color correction. It's based on white point black point correction, we probably all have seen that, but this is handled a little bit delicately. I call it finding a white and black zone, and I'm going to use this image to demonstrate this, and then I'll bring up perhaps a little more difficult image to do the same thing with, but well, here we have the color patches, and we have two primary things that are important that would be a pure white zone in a pure black zone. Somebody zoom in and out to show you various things were going to use this tool called the color sampler tool it's a partner to the eyedropper tool, and when you select that tool, you want to make sure to change the sample size that top part of the option bar from point sample, which is default two five by five this is going to allow this tool to read five or twenty five pixels instead of a single pixel which is important when we're trying to read the information that's in the image when you use this tool you simply click the mouse and when you click the mouse it does several things all at one time I'll click the mouse once in the white patch and when I do that it leaves a target right where I click the mouse the second thing it does it brings out the info panel if the info panel isn't already out and the third thing it does that's important is it actually locks the values in rgb into that target so if I click three more times and I will I'll click on the skin tone and the hair in each time I click you'll notice in the info panel it's expanded the window to four different readings and it's blocked those numbers in I'm going back to the options are at the top left and click the clear button to start all over again because the only two zones I'm concerned with here is the white zone in black son easy to find because I have the patch here so let's click once in the white zone and once in the black zone and to create the correction for this we're going to bring up the levels come in so he's an adjustment level with levels I'm gonna rip these apart and zoom in closely so you can see were clearly what I'm looking at zone number one is the white patch zone number two is the black patch and we're looking at the numeric values and in red, green and blue we have two thirteen to twenty eight to fifty one and it doesn't matter what the numbers are, which one's the highest or lowest that the objective here in the white zone is to match to the highest value that's there so two fifty one is the highest value that we've selected and that's in the blue channel, so let's bring the red and green channel to that value to do that, we simply select the rgb and we're going to go to the red channel in the levels command we have five sliders we have shadow mid tone and highlight under the history graham and their output levels, we have a shadow on highlight slider we're only going to be working with the highlight and shadow slider that's just below the history ram. So in order to match the value in the red channel two to fifty one in the white zone, we're going to take the highlight or white slider and moving in toward the middle of the history ram until the number comes close to our matches to fifty one and we've got it to fifty two that's close enough for now same thing in the green channel will take the highlight slider moving in toward the middle of the history graham until the number comes close to our matches to fifty one so now in a white zone we've removed the color cast because an rgb when the numbers are exactly the same there is no color biased. So once we've set the white zone the next thing we want to do is set the black zone and if you look at the numbers what used to be a twenty seven is now a thirty two but let's look for the lowest value because with this technique we set the highest value mets those numbers and for the black our shadow zone we set to the lowest current value the lowest current values thirty two that happens to be in the red channel so this time will take the black spider and moving in and come close to or matched thirty two I will do the same thing with the blue channel and now by matching the values for the white zone and black son we should have removed an enormous color cast. So if you look at before and after you see the difference now when I turn around and look at this display which is uh not the proper calibrated display I'm looking at here so I mean actually calibrated so that when it goes through the cameras to the internet than it looks like what you're seeing so that is properly calibrated for the internet. That's what? I'm understanding, ok, so who? Because if you're not looking at what I'm showing you now on a calibrated display, it may not look impressive, but believe me, it has removed a cutter cast, and if I didn't have so many cords attached my display, I would turn that around to show my audience. Harry. Yes, so this is called the ninety percent method of color correction it's very quick and easy to do, but the properties about this number one it's very accurate number two um, it strictly for j peg type images images that are not raw. If you had a raw phone, you really would need to use this, we could just click balance to create the color. The other thing is doing it in the fashion that I've just explained, and you may have to go over this two or three times two really grasp it, and I'll do it again, doing it this way. It maintains the highest level of pixel integrity compared to er setting a number and forcing the numbers to go. We're using the numbers that are already resident in a particular image, so I mean cancel this when you bring up this image and what I want to do now is find a white and black zone and I actually already have by looking at the image I've said a white black zone in this image already, but there was no color checker shot here when I did this, and by the way, this was shot I shot this a long time ago in film, so this was actually a scan. So if you have a scanning workflow, I know you'll love this technique called the ninety percent method, so what I've already done is selected my white zone being this white cup in the edge of the plate being black a requirement when you're looking for a white and the black zone is to have some kind of information and there we can't use a two fifty five and we can't use a zero but looking at the numbers there's, plenty of information so let's see what we have here one fifty seven and the red is the highest value let's go to the green channel and there we go. My apologies. I had a correction party in there, so I've taught this before, so I'm going back to levels and will start all over now and when fifty seven is the highest value so let's, go to the green channel, take the highlight slider and try to match one fifty seven, and by the way, I'm looking at the information and info panel not in this window this window simply indicates how far of move the slider over from two fifty five so I'm trying to match the number right here where my cursor is and let's go now to the blue channel and bring this up to two one fifty eight her one fifty seven close to it and now are louis value is forty seven so it's not too far off that's in the green chan also in the blue channel down to close to forty seven in the red channel close to forty seven and now we should have a pretty decent set of color let's back out and take a look at it so this would be before and after okay so that's cleaning up the color that's getting rid of a color caste and if you have a problem image with color this is truly a fantastic technique to do that okay any questions about the ninety percent method but I had a shoot recently and it was a group of who it answers and the teacher wanted it shot on a stage on dso the stage gave really weird lighting like everybody in the middle was was properly lit and then on the ends they were like two blue so is this something that I would be able to use for this for that or what I used a different technique sounds like the lighting in that situation was blue lighting yeah, it was a stage so it's horrible. Yeah. That would be a little different cause the lighting itself was quite different. So this technique is designed to remove a cutter cast from a neutral image so it's best it if you have jelled lighting that's not what this technique is for um maybe one question beats for thirty five says the technique of matching the color channels to each other in the white and black patches. How do we then take that correction and exported to another picture for example the rest of the pictures from that shoot which we'll have the color checker in it, so and I'm not sure if they're working maybe in light room it sounds like um okay, unfortunately, this is not a light room. Take me. Yeah? Or maybe I mean let's assume that they're working in photo shop. Can you speak to that? Yes, let me address that using this picture I'll do this technique one more time and we're using adjustment layer with levels matching the numbers and this one's a little more severe to forty is our target in the red zone let's go to t forty in green to forty and blue and look how far I have to go in the blue it just has to go, you know, to the next atmosphere but that's really changed my black zone numbers twenty eight is the lowest here in the red so go down to twenty eight or close to it and I'm just doing that very quickly here but uh if you look at the difference now before and after it's quite a dramatic difference so if I had ten other images uh that I needed to apply this to I could do one of two things number one I could record in action and that has this adjustment to it. Number two I could bring up a different image and literally take the adjustment layer on dragon over and of course I drug it over to the wrong image but that is a possibility if he had one hundred images you needed to apply that to I would create an action or droplet and use it that way cool really good question that's great couple more if your mind okay, can you use this method on a black and white image? What there be a reason to well, you could but there's no reason to refuse on a black white image of find that you're white black zones are exactly the same number. All right, great. And there was one other one redhead seventeen from liverpool I've been shown something similar using curves instead of levels would that give the same result? Well, as long as you get the numbers to match that's the objective I've always used levels to create cover adjustments and photoshopped curves to create a tunnel adjustments in variations of course the master and curves has been wilmore is you know and I think it's going to be here sometime soon has been recently but when it comes to color too do that it's I found it much better in photoshopped to use levels for cover. All right, so now that I've made you go through the event of the ninety percent method, I'll show you what I call the eighty percent method of color correction and that simply is not by the numbers and by the way, you could actually color correct images if he had the proper white and black zone even on a grace go monitor using the ninety percent method and nobody asked that question why do I call it the ninety percent method? It's? Because it works one hundred percent of the time when you have a white in a black zone and what I found out through experience is ten percent of the time we do not have a wider black zone and that technique doesn't really work and this one does so what I'm going to do is bring out once again the levels come in and do what I call a hist a gram surge and let me check my options here I was trying to get a bigger view here but that's okay? I'll just zoom in so basically I'm going to do when I call shine flew the color so we're kind of a little bit familiar with how I can shine float loosely but by going to each channel the red green and blue channel what I'm looking for is the toe of the heston graham mountain where it lies in the history ram and for instance this area right here is kind of what I call flat lining there is no information and I'm just going to compensate by that for that by bringing the sliders into the toe of the mountain this is also what happens when you hit the auto button usually but this is shine clicking the color so by now the image at this stage looks quite a bit better but going to the refinement stage what I do is go back to each channel as I'm looking at the image and taking the gamma slider are the middle slider and just tweaking it one way or the other and I do that by viewing the image on the screen and when you don't have a white are black zone to get an accurate rendition of the color with the ninety percent method this will get you in the ballpark so this is only to be used after the ninety percent method doesn't mark so here we are now with the raw file most of these techniques or not raw files but I'll never forget when mission lady picked me up to take me to speak at a convention in ohio rushed from the airport to the convention center on our way I saw this picture of this cameron a loss it stopped the van it must have been minus twenty degrees below zero that day but we jumped out shot a few pictures jumped back in the van looking in the back the camera thing oh my gosh, I forgot the white balance the camera oh, but that's okay it's a raw file so here of course are we're going to do is take the white balance tool and click on something neutral and it's pretty much done. The only thing else I would do here would be uh it is my in fact let me go back and want to reset that and go to the current processing algorithm and now once again click the white balance then I'll open up shadows maybe open up the exposure just a little bit and boom that's done so you're shooting raw. This is pretty much if a problem and that's what we do except for the next image that has a little bit different problem. When I first started diving five years ago, I asked a friend to go down and photograph this chart for me because I wanted my job is to really tackle color issues so I really appreciate the fact that he went down to photograph this chart but look what happened he over exposed it so that really lends itself some problems here zooming in you can see the patches here are a bit over exposed so what I'm going to do and now I'm in adobe camera by the way I'm going to take the color samper that's an adobe camera and just click on the white patch at the very top here that's going to lock the numbers and forming in there too it's actually not too bad at this point to fifty two let me click cancel for just a second no we're still looks like it's ah that way so let's take the eyedropper to get a reading and what I want my numbers to be inside what I call the five to ninety five percent rule that would be between five percent and ninety five percent of the total values and what we're reading here our values between two fifty five zero so if you think about the five to ninety five percent value five percent would be thirteen, ninety five percent would be to forty two so I want these numbers to be at our below to forty two and I'm just going to take the exposure down until I have accomplished that just reading the numbers in the upper left hand corner or whatever other methods will want to use this the first time I've actually done this with the new process or engine photoshopped but now we'll take the white sampler are the the white balance till and click on one of the great patches and now we get much cleaner color by taking the exposure down for so earlier that there was a question about this color changed the total values and yes, it does whenever a process and image color balancing is the first thing I do before I do any adjustments with tone and in this case I had to of course take the exposure down and now I can open up the shadows and process the image however I want to and I'll just click cancel on that are just click done for now that'll be fine, but this image my buddy had some pretty severe red skin tone and to correct that I use what I consider one of the most powerful adjustment color adjustments and uh photo shop, which is selective color and selective color even though we're working in rgb file, we have cyan, magenta, yellow and black sliders and by adding sigh in and maybe a little yellow, we can minimize that sunburn effect this even take maybe even a little more gentle. And in doing this, we've kind of minimize that sunburn fact, but the problem that we've created now is we've really taken that really beautiful red shirt and turned it to more orange and now that I've got that, then we'll just take quite paint from the breast tool and bring back just the skin tone without bringing in the red shirt so this technique itself works really good especially if you have a group shot and you have maybe a bride's maid that was just under the tanning bid and the wedding photographers know the problems I'm talking about because their skin tom turns bronze instead of skin tone so this would could be an area correction technique and I've used this quite a bit just going through these very quickly course j pay problems so I'm a great proponent of shooting raw and getting what I can in the image my buddy can I were in victoria shooting having a great day shooting were all over uh place shooting that day I got so excited when a shooting these images got back to the hotel downloaded the images and everyone in my images were j pegs they weren't raw files and I was sick and I'm like can did you set my camera shoot j peg I felt terrible I'm not sure what happened why that happened but I was totally in disarray so what I'd like to share with you is my technique to take a j pig file and bring the best information out of it without generating a color issue color crossover problem and to me besides kurds one of the most powerful tunnel adjustments and photo shop is the exposure control the exposure control came in with the hdr thirty two bit processor whenever that was I don't remember the version cs three we're somewhere back there when they came up with hdr and photoshopped, they came up with the exposure control toe work in thirty two beds and we have access to it with eight better, sixteen bit but it's a brilliant control and of course there's three controls here the exposure offset and gamma, and when you position your cursor over the name exposure offset or gamma your cursor changes from the cursor itself into the scrubby slider, allowing you to use the scrubby slider to make your changes and what's important about that, especially with this control is right now making a gamma change, as you can see, but forward. And when I do that, I flattened out the contrast just a little bit. So we all know what exposure does no need to change that here the gamma is the midtown area which I like bringing that up, but it's flattened out the contrast, so the offset will give us the ability to bring the contrast back in. But look what happens to the image if I take the slider over just a little bit. It just booth contrast is gone crazy, so by using the scrubby slider feature we can bring in the contrast ever so slightly until we've got just the right amount of contrast, and this is what I consider this to be one of the most powerful total controls in photo shop. All right, question from ten thirty seven who says for the ninety percent method, do you always use the number of the red channel, or can you use the number of the green or blue channels instead? Really great question, and it doesn't matter if it's red, green or blue, you always go with the highest value in the white zone and then the lowest current value in the black sun, and we always match the numbers in the white zone first, so it doesn't matter for three green a blue channel, what does matter, which is the highest value for the white zone and their lowest current value for the blacks on very, very excellent question not sure if you want to touch on this and all further by a question from devon, devon is, how would you correct an image where the subject is under exposed and the background is exposed correctly and you want to balance the subject to the background? Well, I love that question, and are we talking with a raw file? And if we're talking from a raw file, then we're definitely going to use double smart processing hang out if we're not talking about a raw file, then the duplicating the j peg layer I'm saying it's a j peg yeah if it's a j peg no need to duplicate the layer that used the exposure control gammas fighter to bring up that and mask in just that front part that's where I would start and and possibly using curves to do selective adjustment and I'm sorry I have to refer to my buddy ben well more cause he's the best at using curves so feel study has creative life seminar even learn how to get the best out of curse that way then is pretty iraq and that's rocking information uh maybe one one or two more questions absolutely uh knife says what should we do if we don't have any information in the blue channel due to bad tungsten light? Whoa what we're getting some stump the instructor question if the blue channel has always been the culprit in digital so if you don't have information in the blue channel I'm not sure I can give you a good answer here but image adjustments I'm looking to see where I would start with that and it would be best for me to have an actual image and look at that and see if there's a solution but you know starting out for ninety percent method is always a good idea that's the good place to start channel mixer could be the answer to that but I would almost have to see that image so ninety percent method are working some advanced features and channel mix or uh is a good answer but the technique of would depend good questions all right, just quick one from harry martin where did you get that underwater chart, please been looking for one like that for a while. Oh, I got that from a friend of mine fred fisher is this name off? Be happy to go back and open up that chart and see if there is a name to it and there is it's called underwater color bar grace go test chart uh and there's the manufacturer from montreal, canada and if I leave that up on the screen is that yeah that's great. Uh ok, I'll zoom in a little bit more there's a phone number and there's the name and there's a website thank you. Absolutely all right, I think I can keep go one more question in the audience when you are shouldn't underwater do you bring that with you each time? Because I know in our water local the colors different each time and I have to like just unfortunately when you go under water every free feet or so you're losing red so by the time you get down to thirty feet there is no red at all, so if you know he strobe lights then you're in trouble uh or you have to create art, which is what I do however um the ninety percent method, needless to say, is the best means around, but you still have tohave a white and black source, so being a new diver and I'm a newbie it diving? Um, that was the first attempt at taking the chart down since then, I've actually taken what is known as a met beth color checker, which we now know is the ex right color check. Ter the beth keller checked, er color checkers is big is this surface right here with big color patches? And just not knowing I took that down in a ziploc bag and sure enough, it got soaked, but I got the picture, but I was in buying air recently and with the color checker passport, we put that into an ipad uh, water safe took that down was able to successfully get some great pictures to create the camera profile, so it's possible to do that, but, um, I would like to get in touch with that company we just looked at in montreal and see if I can't get something to attach to the suit to take down to hold out for that same reason, so I'm glad we asked say I've lost to color checker because I didn't pay attention to where I was putting it and it's off somewhere in puget sound, so you lost the color checker, where in puget sound because I thought I had it attached to me very well and I didn't so there's a bird out there somewhere looking this is one of those colors well I sacrificed one color checker to the ocean but so I'm I'm with you on that okay uh talking about montreal this is a beautiful portrait created by joseph and louise simone ace and poor chair artists who are from montreal and I am going to demonstrate a match color feature that's located in photo shop so uh what they would do they would use a projection background and then a props in the foreground and naturally looking at that the color is way off it's quite different so I created a mass for the window in the doorway so it could use the cutter match feature in photo shop and by the way I've already created this mask I'm looking at and half a channel mess that I created so we don't have time for me to even start to show how created the mask and this is not unmasking feature hey this is an image rescue so I've created the mask holding down the command or control key and clicking on the alfa channel will give me an active selection and what I'm going to do now is command or control jay to jump that selection tio a layer so let's look in the layers panel and you can look that's on the top layer this is on the bottom layer and I want to match the color and there's a feature in photo shop called just at match color so before we go to the match color I'm going to take the rectangular marquis tool and create a selection of this bottom left hand area indicating the color that I want to transfer over to this layer are you with me so far? Okay, so now we're going to go to image adjustments and match color and several things that have to be said here think number one we have to set the source of the images that we want to match which is that's the wrong phone is this file that's the source and now we want to use the layer layer one are you actually want to use at the background layer so let me clear something out here any time you have an active selection and photoshopped whatever you do is only going to be targeted inside that active selection. We all know that, right? So this is the only feature and photoshopped that will allow you to go outside that selection. So now when I ask photoshopped to look at the background layer to get the color, it still doesn't do anything but there's a feature here called ignore selection when applying adjustment so let's use ignore selection when applying adjustment and it transfers the color than I've got selected here over to this other image now what we learned the other day is to become proficient and photo shop you have to become what a good the lender so so the concept here now is to blend this correction and because it's a bit oversaturated the controls we have for blending are luminous color intensity fade luminess we know what that is it's tonal values so let's take that down color intensity is kind of like saturation let's take that down and fade we'll take it right back to where it came from was faded back just a little bit and by now we're getting just a beautiful match between the background and foreground selected regions so matching color when this first came out we were able to match skin tones we still can do that but this is a kind of a hidden feature in photoshopped the match cutter feature is that a painting who started what is wondering was that was not a painting. So is that a painting no there worked with like that but no it is not a painting uh background was actually a photograph created in france our italy and then the foreground was a three dimensional prop so the photograph itself was not to painting. However joseph and louise simoni are known for using paintings in their backgrounds if they know their artists that's probably where that question came from um let's see jim ninety says do you find that x right color checker passport be extra color checker passport gives more saturated colors compared tio q p card and I have to say I'm not sure what a q p card is q p car that's a color management surely uh um and the color checker passport has I don't have one out here but there's two pages to it one is the twenty four patch er one has over saturated colors in it that's used for different reasons so yeah one side would be more saturated but the q c chart um yeah all right there you go, jim all right. Cool that's what those are the questions we have for this particular part okay, well, I'm just about finished here I could take the color match to one more level great let's do it and what that is is the picture I did many many years ago of my daughter when she was a senior high school this was a senior prom and got this dress for her prom so I'm thinking what if that dress was blue? Well let's active I've got a mass for the blue are for the red dress and let's arrange these images first let me pull this image out thank you and let's arrange these images side by side because what I want to do is take a selection tool this election tool just they quick selection to us fine and select this blue oh, horse the layer panel here I go. Refined. I mean, d select. I just want to select this blue outfit and now gonna have this blue outfit selected on the little boy. I now have ivy's red dress selected. We can still go to image adjustment, match color and the source can be the little boy's file. And when we do that, it instantly transfers that color over for color matching. So if you have a client where you photographed and boy, have we done this before, photographed a subject and they ahead one color, then they send you a color palette of the different products. You can actually match the color doing it this way. Okay, so the only other technique I had left was when we went over with the smart objects and that's the back scatter technique. All right? And I'll be happy to do that on a non smart object. And this, uh, happens to be a scan, a film that was shot so long ago that you can't even get this picture anymore. This angle of the flamingo helped because of the bridge that goes across the street. So that's, what a shot some years ago, but it's a scan and the first thing I want to do is find my target emit our target spot museum up so you can see that we'll just use this as a target spot and we'll go to by the way yesterday we went over this technique or was it the day before on smart objects? This is the non smart object version on it goes this way we'll go back to filter um noise and dustin scratches we'll take radius and threshold all the way to the left. Click on the target spot, increase the radius until the spot has vanished and then increase the threshold to bring back the grain and let me zoom up closer because this is before and after and let me go back taking the fresh hold all the way back this is a before filtered effect. This isn't after filtered effect with the right radius if we take the threshold in this case almost twice as much, the concept here is to do a preview and still see the grain structure without the spot and that's something that was hard to do on the underwater image with this technique by selecting okay, the entire image is blurred, but in the history panel photo shops history panel, we're going to click on the take snapshot icon back up in history and then in the history panel we're going to click on the box just to the left of snapshot one this sets the source for photoshopped toe work from you were used the history brush and now all we have to do is take for the shops history brush changed the blending mode to lighten instead of darken we'll do this at one hundred percent and now we're paint over the image the only thing you'll see or the dark spots vanish and the grain structure will still be there yeah, I don't know if you're seeing that I think that's pretty well seen here so once again the only caution is when you get to what I call a sensitive area and let me go back and save where the sensitive areas here it would be in these windows and that would mean just get a smaller brush and paint just around the edges so this would be a technique to minimize that type of problem this would be the back to the future scanners but despite ing technique okay, so I thought I'd end the day with showing you these problems these photo shop did your image ing rescue techniques we don't necessarily need all these today but there comes a time when we will find a need to use something like this so now we have a resource how did he do that? Ninety percent color correction we have a resource is come refer to that so I'm happy to take questions that we have before we end the day so do we have any final questions here in our studio audience everyone's brains are full let's see memories by eliza says, how do you do that for skin tones? The same profit that was going to talk about the color match all was it ok, but we don't have to go before their major skin guys. Oh, yeah. We're just before this one happened to go there. Okay? Uh, I mean, just open up these two images and I'm going to do is select the let's get these arranged here. We try arrangement one more time. Here we go. So we want to take a selection to on the little boy and select his skin tone because I really like a skin time so his skin tone is selected going backto ivy's picture actually have a mass for her skin tone and what we're going to do now is go to match color. Once again, let me hide the active selection. Sorry about that hiding the act of selection photoshopped when we just go to view hide and now image adjustments match color we'll choose the little boy's file as the source to match from and and my own his lair in seconds I was on his layer, so now we're on ivy's later, let's go back to view extra so the active selections hidden now back to image adjustments, match color and now will select his file as the source of color. And it it's, overly saturated right now. So I'm going to take the luminous color intensity and change that to get a really nice match. So that's, how you would match the color of the skin time.

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