Astro Landscape Photography

 

Astro Landscape Photography

 

Lesson Info

Post Processing: Mobius Arch

So, here we have the two images of Mobius Arch with light painting. As you can see, they're both eight minute exposures, 7.1, ISO 1600. The light painting is slightly different. Camera position is exactly the same. I think I like the lighting on this one on the right better, but the main difference between these two, is that one of these images, we used in camera long exposure noise reduction, and the other one we did not. Let's take a look. I think it's pretty obvious which one had in camera long exposure noise reduction, and that would be the one on the left. The one on the right shows lots of hot pixels appearing as these little red, blue, and green specks throughout the image. Now, ordinarily, an eight minute exposure would not cause this kind of a problem, but unfortunately, when we were filming the class, it was about 90 degrees outside. The reason that's an issue is because the sensor generates heat during long exposures, and when it's hot outside, well, that only multiplies the...

problem, and we end up with these hot pixels. Which, unfortunately, lightroom doesn't do much to get rid of them. Anyway, we have a work around and we'll figure out which one we want to use. Alright, so, I think I'm gonna process this one with the noise reduction first. But again, I do like the lighting over here on this one better. So, I think what I'm gonna try to do is mimic this appearance in the other image through a post processor. So, let's go. Okay, so we are starting with the image without, this straight out of camera. The warm LED flashlight that I was using has a slight greenish cast to it, so I'm not particularly happy with the white balance, the way it is. So, I'm gonna take the eyedropper tool, and click on a few spots around the image, and see what I come up with. 2850 color temperature plus 15 magenta. That's actually not too bad. I think I'd like it a little bit warmer than that. Alright, let's see what else we can come up with. A little more magenta in this one. Yeah, I'm just trying various spots in the image to see what it comes up with. That's not bad. I think I'm gonna go, yeah, with that first click, I'm just gonna try warming it up manually by moving the color temperature slider over to the right. Add some light into the rocks there. Alright, that's looking better. Maybe just a touch more magenta. Starting to pick up more magenta in the sky here. But this is looking pretty good. Okay, so let's see. I think the overall exposure is not too bad. The shadows are pretty dark but let's increase the exposure just a little bit, and increase the shadows, and see what we've got in there. Alright, not bad. Okay. You know, I've mentioned using the lens profile corrections and chromatic aberration, which I ordinarily have an import precept that applies to these two things, but in this case we don't so I'm just making sure that we check both of those boxes. And you can see there's some distortion in the lens, and also some vignetting that we've taken out by adding these two things, and the chromatic aberration is most likely, if it's in the image then we'd see it in the stars as kind of magenta or green edges along some of the brighter star trails. Okay. So. Not a whole lot more to do to the overall image. I might play with the vibrance, and the saturation just a little bit. See how it looks. I'm not a big fan of pumping up the saturation. Sometimes even go the opposite direction. But, just a little bit of clarity. About 10 points, and now I'll do some local adjustments on this bush in the foreground. I'm gonna try, again, I'm gonna try to mimic the appearance of the other image. So, let's take local adjustment brush. Reset it. And gonna increase the exposure a little bit. Increase the contrast. Increase the highlights. Increase the clarity, and I'm also going to change the color temperature. I'm gonna try to warm it up a little bit. So, I'm going up about 20 points of warm, or yellow, and a couple of points of magenta. Oh, jeez, we're at eight. I do not have the auto-mask feature checked because there's no real defined boundaries here. Let's just apply the brush, and see what we can come up with. Now I'm gonna create a new brush, and basically tone down the edges around the bottom. So I'm gonna reduce the exposure, and the highlights, and the whites in this case because I basically wanna take this area in here in particular, and darken it down. So, let's have a go at that. And put just a little bit of magenta there, cuz it still feels slightly green. Okay. Alright, now let's see. How about a little bit of post-crop vignette. Move down to lens 20. Midpoint, down to 40. Feather, up to about 75. That's just kinda my default setting that I tend to use on a lot of images. Helps contain the subject matter, and I think it works pretty well for most night images without being really obvious. So, that's looking pretty good to me. I'm gonna go ahead and make a snapshot. Call it two, and, let's see, I'm gonna compare it to the one I made earlier, and see how close I got. Oh, it's quite a bit different there, isn't it? Look at that. Little more magenta. Foreground is fairly similar. Alright, now let's compare it to the other image. And, yeah, now the lighting on the bush in the foreground is better. It's kinda closer to the other image. And, yeah, I think I'm gonna bring this down over here a little bit more. So, let's go back into develop module. Select the local adjustment brush. And, the, I've selected the point that we have chosen here, and I'm just gonna subtract from this area right here because I don't want it to be so bright, and maybe down here just a little bit. Okay, then again I'm pressing the O key to hide and reveal the mask there. And now I can go back into my snapshot, and see how the image has changed. Yeah, it's fairly subtle, so, maybe at this point the thing to do is create a new brush. Reset it. And, bring this down just a little bit more. And, it's here. Cuz I really like this part of the bush, primarily. That's what I'm interested in. Okay, so, letting the full size image load. Yeah, here's one stray, hot pixel. Easy to get rid of, c'mon. There we go. So, this is looking pretty good. Let's see what we can do with the other image. Just to save time, I'm gonna leave the local adjustments unchecked, hit synchronize, and shift over to the other image, wait for those changes to be applied. Yeah, okay, that looks pretty good. Back to the comparison mode. And, yeah, both are looking kinda reasonable. I think I do like the slightly less green look on the one we just finished, so I'll work on this one a little bit. So, we'll go in here, and fiddle around with a color temperature, even though we synched them this one still looks a bit greener. So, adding more magenta to the image. And, a little bit, finding the right balance with the color temperature is where it's all about. Okay. That looks pretty good. And, I'm gonna go ahead, and use the brush on here. Yep, this is the one I wanted to be working on here. Just double checking. Okay, choose a brush. Just minus exposure. Minus highlights. Minus whites. Just bring it down just a little bit. So, let's go into, let's put the brush away. Go full size on the image. Go into the detail panel, and see if we can anything about this noise. First thing I'm gonna do is just slide the color slider all the way over to the right because that is completely nondestructive to the image. And, we'll wait for it to render here. But I don't expect it's going to make a whole lot of difference. Yeah, it actually did take a lot of the color out of those high pixels, but it didn't remove them. It just neutralized them. Made them white. Now if I move the luminar slider way over, again, I don't expect it to get rid of those hot pixels, but just kinda make the detail all mushy. Yep, and there it is. We just lost all our detail, but those hot pixels remain. So, we're gonna have to use another, another technique on this one. I'm gonna go ahead, and use just a little bit of luminance noise reduction, about 15. And, increase the sharpening just a couple of points. And, I think at this point, what we're gonna have to do is go into Photoshop, and try to remove these hot pixels this way. So, to the photo menu. Edit in, and open in Photoshop. Right, so the image has opened in Photoshop. Let's take a look at it at 100%. And, there we go. Lots of hot pixel noise. Now, of course there are about a 1,000 different noise reduction programs, different ways to approach this. I'm just gonna show you one here that I think is pretty simple, and effective. Ideally, though, long exposure noise reduction in camera would be my preferred technique. But, since we didn't have it in this image, we're gonna try something else. So, I'm gonna take the background layer, and basically duplicate it by dragging it on top of the create New Layer. So, now we've got this background copy that's selected. I'm gonna go up to the filter menu, under noise, and choose dust and scratches. Alright. By default, the radius is one, and the threshold, I think, is also one. This is the last time I used it. I had set it to four and 63 for the threshold. What works best for this technique is to keep the radius low, and the threshold basically as high as you can. If you don't get the results that you're looking for from this you might try changing the blending mode to darken on the dust and scratches layer. In this case, it didn't seem to have too much effect, one way or another. But, look at the difference there. That's with only the existing layer, and the copy of the background layer with the dust and scratches filter applied. Pretty much magic. So, at this point, we'll just save the image. And that'll bring it back into Lightroom for us. Then we can look at the two side by side. Okay, so we're back in the Lightroom, and because we opened the image in Photoshop from Lightroom when we saved it, it brings it back in as a PSD, so here you can see this is the one with in-camera noise reduction. This is the one without it that we processed just in Lightroom, and here's the copy that we modified in Photoshop. And, what I'm gonna do now is just select these two images, go to the compare mode, and we can kinda decide which is better. So, on the left, is the image corrected in Photoshop, and on the right, is the image with in-camera noise reduction. So, the Photoshop correction is clearly a major improvement over just what we had before, but I think you'll agree that the in-camera noise reduction is superior, and that's the best way to go. Not only is it effective at removing the noise, but we also still have maintained our overall workflow, which I think is pretty important for a number of reasons. So, in a pinch, the dust and scratches filter works very nicely, but again, use that long exposure noise reduction when it's hot outside, especially when you have an image that you know is a keeper, or you're gonna, going to want to print it. There it is. Press post-processing for a light painted star-chose image of Mobius Arch. Thanks.

Class Description


The solar system and the magic within it can be seen with more than just a telescope. Capturing the milky way and the movement of the solar systems around us can make for engaging and out of this world photography. In this class you’ll learn:

  • What equipment to use and setting your composition in the field 
  • How to find your focus and exposure in the dark 
  • How to capture star trails and the best opportunities based on the lunar calendar 
  • How to capture the Milky Way and create striking panoramas of the night sky.  
Lance Keimig is the author of Night Photography- Finding Your Way In The Dark and leads photo tours around the world.