Join Seán Duggan for an in-depth discussion in this video Color correction of color negative scans, part of Mobile Photography Weekly.
- Hey everybody, Sean here, and I'm back in my impromptu negative scanning studio. And in a previous episode I covered how to use this setup to create copy scans with your camera phone, a black and white negatives and then how to convert those into positive images that you can enjoy again. So, today's episode is focused on color negatives, which are a lot trickier because the negatives have this orange color base to them. So, just a quick recap of what this setup is.
I have a light back here, I have a simple acrylic frame that I'm using to hold the negative, I've got some props to brace my hand and also raise this up here, in fact actually I might put this up here like that, bring it up a little bit. And this just allows me to position this up higher 'cause I've got the negative down lower just to hold it flatter. And I'm going to use a macro lens on my iPhone to take this picture. The reason I'm using a macro lens is because 35 millimeter negatives are smaller, and in order to fill the frame I just need to have this macro lens.
So I'm going to do a quick shot of this and then most of this is going to be concentrating on how to invert the tones to make it a positive, but then how to deal with the horrendous color cast that's going to be created by this orange film base here. So, I'm going to get up close here, make sure that the macro lens is seated right, and if I need it, this is a brace here I can brace my hand with. So focusing on a macro lens like this is just basically, you get in close to get it focused, and then once you get it in there then you can maybe tap the the screen to have the camera focus.
Alright, that looks good. Let's turn this light out, and now let's dive in to the processing app to turn it into a positive and then deal with that horrible color cast from the orange film base. So the app that I'm going to be using is called MaxCurve, right down here. Now MaxCurve is only available for iOS. But, you just need to have on Android, you need to find an app that allows you to adjust the individual color channels, red, green and blue, because that's what we're going to have to do here.
Let me actually get rid of this lens, we don't need that on there. Alright so I'm going to load up my latest negative here, and let's just go into the rotational, controls to rotate it. I'm not going to worry about cropping it at this point, we'll do that later. So MaxCurve has several different curve sets. It has a RGB set of curves, CMYK, a lightness set of curves, LAB, there's just so much you can do with MaxCurve, and if you enjoy working with curves, this is kind of a total geeky app you're going to love.
I'm going to go into the RGB kit, which is this three circles there, and you can see it gives me access to the main RGB curve, which is the luminance and then the three colors. The first thing I'm going to do is go into the RGB curve, and this is where I'm going to do the initial inversion. So, I'm going to just invert this curve right here. So I'm going to grab the highlight point here and drag it all the way down to the bottom, like that. And then I'm going to get the shadow point and drag it all the way up to the top. So now we have the basic inversion.
So now I have a positive image with a horrible blue color cast, right? Just what you've always wanted. Next, I'm going to tap this little grid button off on the side which gets me back out to where I can see my other curves, and now I need to go and work with red, blue and the green curve to try to correct, counteract the effect of that orange film base which yields this kind of blueish cast. So let's go into the, since blue is the strongest color there, I'm going to go into the blue curve because the opposite of blue is yellow, so I know that I can counteract the strong blue there, and you can see dragging it up adds blue, dragging it down makes it more yellow, okay? So that's a start there.
And I'll come back out here and now I'm going to choose the red curve, because the opposite of red is cyan, so red and cyan, so I need to add red here to counteract this and you can see now we're starting to get this architectural shot looking a little bit more natural in terms of the neutral tones of the concrete. Let's go back out here and go to the green curve. Obviously it's too green still, so the opposite of green is magenta, we can pump in a little magenta there.
So I'm going to drag down on the curve to add magenta in there. Now, if you don't know which way to drag the curve, you know up or down, just drag it one way or the other and you'll soon figure out which way it needs to go. So there we go, that's better. Got rid of that green, but a little bit too much magenta so we'll back it off a little bit. So, that's not bad. What I would do additionally is I would probably go in to the luminance curve, and play around with some of the contrast, maybe.
If I didn't want to do it there, I could go in to the light curve here and work with the contrast curve and I could play around with this to add contrast to the image, and now that's looking a lot better right there. There we go. So, it's not perfect, but it's not bad at all, considering I'm doing this very quickly on a mobile phone. For a lot of these negatives, to be frank, what I would probably do is I would probably bring the images onto the computer and work with them in Photoshop, I would have a lot more control, but this is actually not bad.
It still could use some more color correction, but not bad. So let me show you another really interesting feature in this app, and that is that you can save a preset of any curve you have created, and of course that's going to be very useful if you decide you have a lot of other interesting old color negatives that you'd like to try this on, and you don't have to reinvent the wheel every time, you can just do a one button application of the preset, and it will get you most of the way there. So I'm going to scroll down here to the preset button, this little one on the end, and there's a button right there, Create New Preset, and I can give that a name if I want, I'm not going to worry about giving that a name right now.
I'll just tap Done, and you can see that what it does is it saves the preset using the thumbnail of the image that you used to create that preset so you can easily find it again. I'm going to back out and show you how easy it is to apply this. I'm just going to tap the Home button up here and for now, I'm just going to say don't save, and I'll just open that image up again, and I'm not even going to worry about rotating it here, I'm just going to come all the way down to that preset button, and I'll just tap that and boom, presto chango.
That was easy. So, that is MaxCurve, a really excellent app for giving you a curve-based control over many different aspects of the photograph. But to make this sort of correction, all you really need is an app that will allow you to invert the image and then have individual controls over red, green and blue. And you know the cool thing about this process is it's not intended to be a replacement for having an actual scan made, but being able to do this with your camera phone and some really inexpensive gear like this, it's so rewarding to be able to rediscover these old negatives that you might have lying around and then you can enjoy them again and share them with your family and friends.