Exposure vs Brightness vs Gamma - Affinity Photo Beginner Tutorial

Key Takeaways

hello my friends how are you doing today we are going to look at the difference between exposure brightness and gamma a mystery to a lot of people that we will reveal today and make super simple my name is olivia i'm a professional designer and i want to thank all of my patrons who support me and make these videos possible okay let's get started so here we have a landscape but have something better than that i have a gradient that goes from black to white and even better i have a scope up here on the right side and because the scope is reading a picture from left to right and the darkness from low to up in the scope you can see that we get just a simple clean line and this clean line will make it extremely simple for us to understand the difference between these separate settings all right so the first thing we want to do is to look into affinity photos manual and here it says exposure controls the highlight shadow levels of the image while brightness controls the lightness darkness of the image well that doesn't really tell me anything to be honest so we can close that and we will look at our scope and we will start with exposure i will turn that on i already prepared the adjustment of course and so look at this if i turn this down you can see that my values are going down and everything gets darker in the picture and if i turn it up everything gets brighter in the picture and this is kind of similar like when you adjust the exposure in your camera so another thing that's really important to understand here is again when we look at our scope we have this clean line here and when i move it over you can see that the line stays straight and the zero point where it's completely dark stays unchanged and if i move this in the other direction still the line is straight and it's just moving up and again the dark point is staying the same now where do we know this look from from our curves of course so if i open up curves what you're going to see is if i move this down i get the exact same result in my scope and if i move this point up again i get the same result so basically this is what exposure does inside of affinity photo if you just take the white point of your curve and you move it around the outer edge of your curve window this is what's happening in the picture right and we can actually also look at our picture here and we can see that we can turn this down so everything is getting darker and we can turn this up so everything is getting brighter so of course overexposed underexposed right so this is kind of easy to understand now let's go to the next one in this case we look at brightness and now it gets interesting what we are seeing is that when i move this down what i'm getting is well we are still at the picture so we have to switch over to our gradient so we are getting this at a curve so this is really interesting and you can see that this has a bigger influence on the brighter values than it has on the darker values and if we move this over again we are getting a curve and this is really influencing that area here quite a lot and in a certain sense you can say that it moves around the spread out of the darker and the brighter areas in the image right so if we go completely dark it's not like the picture is completely dark if we set brightness to minus 100 and if i set it up to plus 100 it's not like everything is completely white this is not the case it just moves around our middle basically all the the values that we have between complete darkness and complete brightness and if we look at our picture again let's switch over here and now look at the scope what's happening if i use brightness everything is getting pushed down but in an equal way it's kind of getting squished together like it is a sponge right and if i go to the other direction it is getting stretched out again like a sponge but now i'm stretching it out so this is what brightness does to a picture last but not least let's have a look at what gamma does again look at the manual and it says determines the distribution of mid-tone pixels in the image so you redistribute them either towards the black point or the white point that sounds like brightness well it's kind of different and it's kind of different in the sense that first of all you find gamma not as an individual setting but you find it inside of the levels adjustment here in the middle and now look at what happens again with the scope over here i am now at one which is the normal neutral setting and if i go towards zero over here you can see i again get this kind of bend but this time it's a different kind of bend as before and you will see how it's different if i push this down to zero because then it is just a flat line and everything in my picture including the black value is completely white there's no darkness left whatsoever so redistribution sounds a little bit underestimating the actual drasticness of what is happening here now the interesting thing is what do you think is going to happen if i push it to the other extreme would you think it's going to go completely black or do you think something different happens well here's the thing i'm now at one again neutral i push over to two you can see we again get this kind of bend here that's kind of softer and it's not getting that much stronger either so i'm now at two and well it's a little bit different it pushed it a little bit towards my white levels although the complete white is still white so you see the black point and the white point are still at their origins and then the other values moved over but just by a little bit so this is also interesting to see and also of course has an interesting application in our picture because now if we look at our photo here and again look at this area here for the scope if i move the gamma over what we are seeing is nothing because i didn't turn it on what we are seeing is that this is moving things up but you can see that it's moving everything up including the black values you can see here everything is pushed towards the ceiling it's quite interesting and of course if i push it up here to zero everything is stuck against the ceiling nothing is left while when i move this over to the other side what is happening is that the values are getting pushed down but just by a bit not too much interestingly enough and this is the maximum value you can see if i try by hand to enter a higher value not going to happen 2 is the maximum value so this is also interesting also especially when you think about making a picture darker without influencing the bright areas too much gamma can be a really good adjustment for that as you can see here push this a little bit over the darker values get darker but the brighter values kind of stay the same so for that purpose it's actually pretty useful and here's a little hidden trick inside of the levels adjustment when you use the output white level or the white level it does exactly the same as the exposure adjustment let me show you let's go back to our gradient here and you see if i use the output white level which means that i reduce the brightness of the white levels and move this down you see that we have this straight line coming down so this is exactly what happens if i push exposure into a negative value and now if i set this back and i use the white level which means that it brightens up all the other values you can see that the same thing happens as if i push exposure to the positive value so we have this straight line the black point is staying the same and all the other values are getting pushed over to the other side and this as is really also interesting to understand means that the black level and the output black level is kind of an inverted exposure setting because what you cannot do with any of the other settings is to make black get brighter i mean complete black other than setting gamma to zero so what i can do here with the black level and you see again we have this line but now this line here is moving over so all the values are getting darker until they are completely dark so it does the inverted thing of what exposure does it moves the black starting point not the wide starting point and also if i have the output black level if i move this over all the darker values are getting pushed up so what you're seeing here is that now when i set this back you can see down here we have our starting point with absolute black and if i move this up you can see that this point is moving up while the line is staying straight so i move this up a little bit and more and more and this line is staying straight just this area is moving up like as you would do in the curves and now here's the magic here's why this is important for you if you print pictures what you want to avoid is to have areas that are completely black or completely white in the print because white completely white would just mean plain paper right so what you're doing here you go to the output black level and the output white level and you set the output black level to one percent and you set the output white level to 99 like this so you know you don't have any values that are completely black or completely white in your picture alright i hope that was interesting thank you very much for watching maybe join my facebook group and see you soon bye