Blend If to Hide or Reveal
Now we are going to talk about something called Blend If for the people that saw my tips class this will be somewhat familiar but I'm going to show more examples here. We have this circle here. Blend If. Black and White. Up against the gray background. If I double-click to the side of the layer we are going to get the Layer Style window and we're going to get this section here called Blend If. Now, this is not really a selection yet. We can make it into a selection later but it allows us to hide and reveal pixels much like a selection or much like a layer mask, rather. Using this layer, the layer that is currently selected or the layer underneath by using the luminous values that's what gray means or one of the channels that we looked at in the previous example, the red, green or blue. So let me show you how it works. See how when I click on this slider, this point here is the black point notice how its disappearing on that circle. See that? See how it's disappearing? So, that's how th...
is works. If I bring it all the way to the other side it stops right there, can't go any further. If I hold alt, option on the Mac, and click on that button, it splits in half and now it creates a smoother transition between the invisible pixels. So basically anything that's black to this shade of gray, right here, is invisible. This right here. Right about this point, there's gradual transition from invisible pixels to visible pixels and you can also do the same thing with the white point, if I click and drag the white point, it does the same thing but it goes the other way. So, I'm hiding pixels based on their luminous values. You might be thinking, "Well that's cool." So, I can show your really cool effect on how that works or a cool effect that you can create with that Blend If. So we have the word that reads "clouds" and then we have clouds underneath that so I want to make it seem as if these clouds were in front of the text even thought the text is on top in the layer step. So, I want to bring out bright pixels. So, instead of working with this layer, I'm going to work the the underlying layers, the layers below. So, I want to bring out the bright pixels from the layers below so I'm going to use the white point slider to bring out those white pixels. So, I'm going to click and drag to the left. See how those clouds start appearing over the text but the transitions are way too large so I'm going to hold alt, option on the Mac, and click, splits those in half and notice now, how it seems as if those cluds are in front of that text and this is all non-destructive which means I can move the clouds or change the adjustment. See that? See how I quickly created that effect of clouds being in front of the text just by adjusting the Blend If sliders. So, that also works with color. We have this color wheel here, which is what you see on the screen. I can also double-click to the side of that layer to bring up the Blend If or the layer style window with the Blend If options I can select red, green and blue. All the different channels. I'll select red first. Notice what happens when I start moving this point. It removes the reds and actually when it gets to the other end it stops right there. Does anyone know what the opposite color of red is? Cyan, yeah, cyan. So, the opposite of red is cyan. That's why it stopped there. If I remove all the colors but red, I start with cyan because that's the opposite and it stops when it gets red. With green, the opposite of green is? Magenta, yep. It will stop there in the Magenta. You can see it there and if you move the black point, which is the opposite of green, magenta is what gets deleted, well not deleted, gets hidden first and it stops at green and with blue the opposite is? Yellow, yeah, yellow. So, it stops here and of course it goes there. The yellow would go first if we use the black one. So, you can start imagining the power that this gives you knowing that you can hide target colors with targeted luminous values and you don't have to worry about making selections if the image you're working with has a color that you can work with in terms of lumens and in the shade of color that it is. In one of the examples which really demonstrates the power of this is by removing skies. If you have a clear blue sky you know that you could select the blue channel and we want to hide the blue pixels. Now, we don't have to worry about making a channel based selection in this example that's the one way that we would create a mask for this to get all that detail we would need to create a channel based selection to get the birds in there, we would need to do a lot of work since the sky is blue and nothing else is blue we know that we can hid blue and keep green so I can select the blue Blend If channel and hide the blue from that layer. Like so. So, it's a really great way of making sky replacements. We have a layer right below that has a sky. One thing about making sky replacements, a lot of people don't think about perspective. Perspective is really important when you're compositing in this case these are two photos that I shot so the original one I was looking straight up, shot a photo of the birds for the clouds I had to do the same thing, look straight up and shoot because if I had shot clouds that were in front of me, like looking into the horizon at the beach or something the perspective wouldn't match and it would look fake. So, that's always really important, the perspective of thing that your compositing need to match, even clouds and skies. I was able to remove the sky really easy. One of the down sides is doing this technique is that if you decide to make an adjustment, for example an exposure adjustment layer, it will bring the sky back because when you adjust the luminous values or the colors of the image obviously the blend changes. One way of keeping transparency and making into a selection, making it into a mask, is by right clicking and selecting "Convert to Smart Object" and now we have transparency and the way that you can tell we have transparency is by looking at the layer thumbnail we have transparent pixels as opposed to having the blue pixels here and I just pressed control, alt, z, command, option, z on the Mac to undo. So, if you want to make transparency out of the Blend If adjustments. Right click on the layer and select "Convert to Smart Object" and just to show you a different example we have this texture here with the word "Rust." I can hold control, alt, G, command, option, G on the Mac to apply that image onto the text and I think that was in the last class when this question was brought up but that's how you would get an image into text. You have your photo layer, control, alt, g, command, option, G on the Mac to make it into a clipping mask. A clipping mask simply means that they layer that has a down pointing arrow is being controlled by that layer, the layer below it. So the transparency of this layer effects the transparency of the layer above so whatever the active pixels are on the layer below, those will be active pixels in the layer above. So, that's a clipping mask. So, I could add this, I can even create a more interesting effect. I can double click on the side of the texture layer and I can use the gray sliders to make that rust even better. See that? See how I only kept the rust? So, maybe in the effec that I want to use, the effect that I want is maybe keep the original color of the text but include that rust. You can actually see how the rust is almost peeling, it's go that effect of peeling just because I'm hiding those pixels really easily just because I know that I want to keep dark pixels and hide the white ones. Once you start realizing what pixels you want and don't want then you can start thinking of the tools that hide or reveal those pixels or I could do the opposite, I could keep the top part of the rust, hold alt, option on the mac, split those in half and you get a different effect, like so. So we hide all the dark pixels and only kept the brighter pixels and you can create that effect. The great way about working this manner is you're always working non-destructively so you can just say, creative live photoshop week and we can't fit 18 but you get the idea. You're always working non-destructively so I think this I a really good technique for you to use and just like before you can convert this into a smart object and now we have a layer that just has those pixels and transparency. So you can use it as a layer mask or you can actually make a brush out of that too.