March 10, 2007 Lightning and Night Photography
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Edit: A reader noticed something worth pointing out and thought that I should do so. When I say I change ISO settings, I'm doing this on my digital camera....if you use film, to do this you need to change your film to a different film speed(by purchasing a faster or slower speed film). Night Photography Section
I'm typing this up for a couple tips on how to shoot lightning or night shots, as well as just so the unknowing can maybe get an idea why/how night shots look like they do. There's really not much to either, so I probably shouldn't even call it a tip deal. Some folks that don't shoot much at all may not get it, so I figured I'd try here. If you don't get things at all and have no grasp of exposure and cameras, I'd read the January 26, 2007 entry before this one. Shots during the day are much brighter and therefor don't need the shutter to be open long to expose. Some think that is just how a camera works, you push the button and it takes a picture, without realizing the speed of that shutter varies. I'm mostly typing this for them. Even during the day that shutter speed as a certain quickness to it. But, basically it's all going to be so fast you have no way of noticing it. As the light gets lower you might notice it. Most people don't shoot things in the dark, so I guess they have no experience in seeing how much it slows down the shutter to get the exposure right. Changing the ISO speed from 100 to 1600 will make the sensor much much more sensitive and therefore need less shutter duration to get the exposure right. Here is an example.
This is obviously at night. I'd say the exposure is about as well as it needs to be. It was handheld from within my car. The shutter was 1/20th of a second with a lens aperture of F4(as open as it goes on that lens, letting in the most light possible, which allows for the most light possible). The ISO was set as high as it would go to 1600, making the sensor as sensitive as possible, which will keep the shutter as fast as possible(fastest iso and fastest/most open aperture will yeild the quickest shutter you can get). I knew I had to handhold it and would need the widest/open aperture(F4 on the 17-40L F4) and the fastest ISO setting, to get my shutter up as fast as possible. 1/20th of a second isn't very fast, but it is fast enough for a wide angle lense(the more zoomed in or telephoto one is the faster shutter then need while handholding things). I was at 17mm on this. Now what happens if I'd try to do this same shot with an ISO setting of 100. Well each ISO increase is worth one stop. The increments are 100, 200, 400, 800, and 1600(stops work by doubling and halving...same with the shutter numbers and aperture numbers). So 100 ISO is 4 stops SLOWER than 1600 ISO. So to get the shutter speed you'd halve 1/20th 4 times. Camera's do their increments for shutter and aperture by 1/2 and 1/3 moves. So if I want to know what 1/20th is 4 stops slower and I can't do the math I can put the camera in manual and just count. My canon uses 3 steps. So you'd do the 3 steps on the wheel 4 times to get the 4 stops change. Here is the first stop going down from 1/20th of a second. 1/20 - 1/15 - 1/13 - 1/10 Obviously 1/10 is half of 1/20, so that is one stop slower. If I finish this out the remaining three stops I'd be down to 8 tenths of a second(nearly a second). So what that all means is, if I shot this at F4 for the aperture and used ISO 100 instead of ISO 1600 I would need my shutter to be 8 tenths of a second to capture the scene the same, as far as the exposure/brightness goes. Guess what, it's going to be hard to handhold that shot if you need to be still for about a whole second. So why not use 1600 and not worry about it? Noise. If you look at the sky on the above shot you can see the noise in it. If I used a tripod and did the ISO 100 and 8 tenths of a second route, there'd be no noise at all. Also, motion isn't just the person trying to hold the camera still while the shutter is open, it's anything in the shot...like say a passing car in this case. 8 tenths of a second will give a good blur to about anything. 1/20th would come a lot closer to freezing any slow action. Now that shot was a good example of something "brighter" at night. It also depicts reality fairly well. There are a whole lot of other things to shoot and do, often things that don't show reality(since they'd be pretty much BLACK/dark images). Just because they don't show things exactly how they appeared doesn't mean it is a "photoshopped" image. I think a lot of people that don't do much of anything with photography, will jump to that conclusion with many night shots. Longer exposure photography at night can open some pretty cool worlds, and most certainly aren't "photoshopped".
Does this portray "reality"? In other words, is this how the sky looked visually at the time? No. Is it "photoshopped"? No. What is it? It is what happens with long exposures at night near any decent sized town or city. First off, here are the settings for it. ISO was set at 100....slow/least sensitive, but most noise-free. The aperture(lens opening size) was set to F4, letting in the most light I could on this lens. (Yes I'm beating these ISO and aperture reasons to death in these first couple entries, but only for those just learning) The shutter speed I used was 89 seconds(it's open that whole time, letting whatever is happening expose on the sensor). This gave the clouds some motion. Is there anything scientific about the 89 seconds? No, not really. I just let it go for a while then stopped it. It's fairly hard to "mess up" such scenes. This night stuff is really pretty darn simple! Open the lens as much as you can, then use slow or fast ISO settings for your need. So why are these clouds at night redish orange? They will show up whatever color the lighting is off the area lights. If one wanted they could certainly shoot the scene exactly like it looked. Boost that ISO up to 1600(or higher if you camera is capable of 3200) and use the shutter that makes it look right. 90% of the time it is much more fun to do long exposures and see what shows up on your lcd screen(unless you are shooting film obviously, which should produce a similar photo once it is developed).
This above photo is one of my favorite night shots. It is very easy for me to understand how someone with no experience in photography would jump to the conclusion this was just photoshopped, created with a computer. Hell I could understand that conclusion from those who've done some photography, but never messed around at night. This is partly why I've made this entry. If you think it is fake and have a camera, and live near any city lights, get away from them just a bit and mess around with some long exposures. Now with this one, I was further from the lights and it was darker out visually...when compared to the one before. For this reason I needed to use ISO 800, much more sensitive than ISO 100. The lens was again open at F4. Shutter length was similar at 78 seconds. Again, it's night, it was dark where I was. I'm a good 2 miles north of the edge of town. While looking at the sky, I of course wasn't seeing this appearance. The camera at ISO 800, wide open, and over a period of 78 second however did. The little white spots are stars that exposed when they weren't being blocked by the patchy clouds. The blur is because the shutter was open for the exposure 78 seconds, and the cloud were moving during that. I held as still as I could for the shot. Since it was so dark, I didn't even leave a blur when I left and ran back to the camera. The only reason I exposed as bright as I am is because I stayed in that one spot. There are several more examples HERE.
Lots going on here. Looks like the sun coming up doesn't it? It's the moon very low to the horizon. It was rather yellow or orange and mostly blocked by those clouds. The streak above it and to the right is a passenger jet(gives a good sense of length of time the shutter was open by the distance it moved). This was at F4, ISO 100, and for 68 seconds. Notice the smear on the river....ice. Notice the area not lit up, the ice looks red. That's because of the light on the side of the building. The other ice looks white since some brighter truck headlights were shining across the river. You can see the stars left a trail too as they moved(just like the sun) during that 68 seconds. So again, this ain't photoshopped, it's a long exposure at night.
Very long exposure at night. 4850 seconds at ISO 100 and F4. A camera has a thing called white balance. It will offset the color to a cooler tone like blue or a warmer tone like red. It's usually rather important that that is right. If it's off then the colors in the image will be off to that side. When it comes to night shots, with all sorts of shades of city lights hitting the clouds or moisture in the air, it can be a bit tricky knowing where it should be. Usually the camera's auto modes do a great job. If you shoot in RAW format you can easily correct it after the fact, so it's not that important to get it just right at the time. Well, I pretty much gave up on the sky with these star trails. First off, if you ever want to do looong star trails, you'd better find a very dark place far from the city lights(I was about 50 miles north of Omaha on this one). Still, there will be lights around and so the sky "should" be some fashion of red or yellow thanks to them.
This is another favorite of mine. I'm not even sure why exactly. It seems because the exposure came out so well. It's sort of another example of a night shot that looks close to how reality did. This was a darker scene though, and I did not use 1600 ISO to get it right. This time I used 100 ISO, F4 and the exposure was 25 seconds long. So, I can do the opposite math as I did on the first image on this page. I can find out what shutter would get the same exposure if I used 1600 ISO instead. That shutter would be 1 second and 6 tenths, instead of 25 seconds with 100 ISO. So either way, to get this one that looks very close to reality, my uncle here would have to hold still....for 25 seconds at 100 ISO. Using 100 ISO leaves a very clean, noise-free image. I did not have to handhold in this case, so going this route was possible, given a tripod and him holding still for 25 seconds. We also had to fan the lights around so one spot wouldn't burn in too much(with his he could have probably just adjusted the light and been ok...so in a sense that part wasn't like reality, but it would have been had it been set in a less focused manner). A bit late to mention this, but when it comes to focus you obviously aren't going to have much luck with auto. Do it manually.
Photoshopped? Nope. No need to. The only difference in settings between this one and the one above it was I used ISO 200, still at F4 and for 25 seconds also. My uncle is carrying it out at head height. Why doesn't he show up? He is a whole lot dimmer than a pumpkin with a candle in it. We(sister, me and her kids) used our lights on the building a bit, so it is illuminated. We kept them away from him as he walked out so he would be "lit up" as little as possible. So since he was moving and never standing in one location very long, he just doesn't show up, but the stuff behind him does because it was getting to the sensor much longer than he was in any spot. When the shot began he held the head there for just a second or two so it would show up, then he walked it out slowly, over the 25 seconds. Actually he was probably out of the shot before 25 seconds was up, maybe as quickly as 15 seconds. See the next shot for "proof" that is how it works in the dark.
It's a shame I had to use this image in another location on the site lol. Shot details, F6.3(not as open as F4, but fairly close) ISO 100, and for 30 seconds. Here is exactly what went down on the shot. I have the cable release hooked up and it is set on bulb(this lets you push the button on the cable, and while it is down the shutter stays open...as long as you want, or till the batteries die). I push and lock it to start the shot. I then run out and get into the shot. I have a flashlight in my hand, with my hand over the end. I start the M at about chest level. I had to have the flashlight moving right when I took my hand off, otherwise it would leave a brighter spot. So I move it up and down making the M, then I cap it off right when I'm done. I then hop to the side and do the same for the O, then the other O, and finally the N. The shutter is open seeing me draw the word MOON. I then cap it off(note the brighter spot on the N where I must have slowed down). I then walk closer to the camera, bend over and shine it on my butt. So I'm standing there(obviously) and only the area the light is on is showing up. So if you aren't lit up and you are moving around, you just won't show up. Now if I stood there for a few minutes(even without the light) I'd start to show up. So the pumpkin thing above is similar, my uncle most certainly carried it out of there. So anyway, if you are new to photography, or not even knew, but maybe don't do it,...just because it doesn't look like reality that doesn't mean it was photoshopped.
Lightning Photography Section
There have been some questions on lightning, so I figure I'll say what I can here. Some don't get how a person can be fast enough to catch it. If you want to shoot it, pound this here into your head. SHUTTER SPEED MEANS NOTHING. I hope using the above images at night helps paint the picture here when it comes to how lightning is captured. It's no different than me spelling MOON on that image. All you really do is leave the shutter open till a flash happens. Wala! Sort of. Think of drawing a lightning bolt on a piece of paper. The paper is fine till you draw on it right? The open camera shutter will be the same way(mostly, more later). The flash happens and the bolt essentially draws itself on your camera's sensor(since the shutter was open allowing light in). So you do a long timed shot of say 5 to 30 seconds where the camera counts down. Or, if your camera is capable, you put it in manual and spin the shutter down past 30 seconds to where it says BULB. Make sure you have a cable release to plug in(they are cheap). Then just push the button on the release and lock it(the shutter open) for as long as you like(or till the lightning decides for you, by it taking place). So the lightning flashes and goes away...shutter speed means NOTHING. If you are concerned with shutter speed...don't be. While the lightning isn't taking place it's just dark, so don't worry about length of the shutter. The only shutter concerns one needs is when they are shooting something lit up, like in a city or near one. In that case, you just shoot for the scene and hope your bolt happens during the shutter length your scene required. I'll show examples in a bit. What do you need to worry about then? Aperture size. Pound that in your head. What is brighter, a bolt a block away, or a bolt 5 miles away? If a bolt hits a block from you, you'd better hope your aperture setting is SMALL, like down around F16 or smaller. It's going to be blinding, so you'll have to be restricting the amount of light getting to the sensor. If you are more open, with a wide aperture of like F4 or bigger(smaller apeture numbers mean larger openings letting in more light) that shot will be TOAST. It's going to be completely blown out. If the bolt is 5 miles away, and not terribly bright, you'd most likley want to be very open with the apeture. If you are F16 then you'll be lucky to find it anywhere on the dark image. This is how you control your lightning photography, it's NOT by shutter speed. There is another control to use for lightning, and that is the only one remaining...ISO settings. It's much the same as aperture. If you get a bright bolt nearby you probably won't want to be on 1600 ISO(it will blow it out quicker than 100 ISO....obviously..it is more sensitive). If for some reason you wanted/need to stop down the aperture to like F20 or something, then you might need 1600 ISO to get the bolt to show up(that would be one odd combo for lightning). If the bolt is far off and not bright, you might need to move past 100 ISO even if your lens is also wide open. The extreme majority of the time I need to be on 100 ISO. I'll start off there and wide open. If they are too bright and blowing out, simple, stop the lens down till they don't. It's all pretty simple. If you are wide open and on 100 ISO and they are dim, just how many choices do you have to make them better? One, increase the ISO...simple. As far as focus goes, same as any other night scene. If you are trying to do it on auto focus you should slap yourself.
What is wrong with this above shot? Not a lot, but the foreground on the far left is blowing out from the light above there. This was shot at F5.6, ISO 100, and for 45 seconds. Looking at the lightning I can see the aperture and ISO settings are about as good as I could get them(close enough). If I increase the ISO to 200 and decrease the apeture to F8.0 how would the lightning look? The same. ISO 100 to 200 is 1 stop more sensitive. Taking the aperture from F5.6 and making it smaller to F8.0 is 1 stop as well. Shutter means nothing for the bolt. The bolt just popped up there for its second during that long 45 seconds the shutter was open. Where that 45 second does matter is the SCENE. The blowing out on the pavement to the left would lessen if I decreased the shutter length...see below.
Lightning exposed well enough on this one? Yep. The color change is only due to some of the flashing closer and overhead on this one. Look at the foreground this time though. That street light blow out on the left is much better. Why? Here are the settings on this shot. ISO 100 again, and F5.6 again, but the shutter duration was only 16 seconds, a third of what it was on the other shot. So, for the lightning itself, shutter means nothing, but for the scene it very well could. Now if I was out in the country with no lighting to worry about, I could probably let the shutter go on for minutes.
Know where I'm going with the above image? Not all bolts are created equal! I'm glad I was using the same settings for all these, as far as ISO and aperture go. This was again, 100 ISO and F5.6. Can you guess the shutter length by looking at the blown out foreground to the left again? 44 seconds. Evidently these bolts were only happening about that often(seems about right thinking back about the chase). But anyway, check out the 2 bolts. They had the exact same exposure setting(obviously they are in the same shot). If I remember right, the left one not only was a much brighter flash, but it also pulsed, which gave it a longer time exposing on the sensor. So to have captured that particular bolt I would have had to been stopped down past the F5.6 I was at, probably to F11 or more. But, had I done that, then the bolt on the right would be very dim. All things considered it would be better to have one really dim and one correct, as opposed to this blown out one with the other. Usually these brighter ones aren't nearly as frequent, so you are shooting for the others. Lightning is generally very simple, but it can become considerably harder when you toss in a city setting. The city setting limits the shutter length, which means you have to keep snapping away, rather than just leaving the shutter open forever till one happens.
The best lightning comes at or around twilight hours. This is after the sun has set, but there is still *some* light. The above shot was considerably darker than it appears. It wasn't pitch black out yet but it wasn't far from it. This was F4, ISO 100 for 11 seconds. If it still early in twilight then shutter length can be a problem. If it is a bit bright yet then you obviously can't leave your shutter open long. You can't stop it down either, because then your lightning bolt won't show up. So twilight stuff is cool, given your bolts are somewhat frequent. Notice the mammatus are pretty blurry, since they moved during the 11 seconds.
Here is one of my favorite shots. This, like the other night shots, I can understand the unknowing thinking it is a creation of photoshp. Truth is, it is not "photoshopped", other than your normal processing required with shooting in RAW format. It is real, 3 other chasers were there and I showed them a couple of these on the lcd screen on my camera. I think a person is really missing out by never doing exposures longer than say 10 seconds(often much longer). Did it look exactly like that in person, no. It was very dark during this shot. There was just a smidge of light left after sunset, which can be seen on the left. You can tell it is night, just note the headlight trail on the right from cars on the highway. It is crazy how much this looks like a day shot very near sunset, even before by the appearance over there. It was dark enough at this time that if someone was standing in that field, 30 feet away, you'd probably have no idea they were there. The tiny bet of left over ambient light from the sun just brighten things up a bit during a long exposure. In this case the shutter was open 25 seconds, with an aperture of F7.1 and ISO 100. In-cloud flashes also help with illuminating the storm itself. Since the shutter was "only" 25 seconds, the storm structure really isn't going to change much. It might smooth it some, but the general appearance was like that. You can see the kind of strobe appearance to the right side of the base, as different flashes would light it up a bit, then it would stay dark till the next one, after it had moved some.
Here is an extreme case of needing a very open lens, with fast ISO with lightning. I had my canon 50mm F1.8 on for this, so that lens will open all the way to 1.8, compared to the 4.0 on my 17-40L F4. That is a big increase in exposure since 1.8(being wider) is much "faster" than 4.0. The other aspect of this shot was the ISO used was 800. It's rare you'll ever need that much "oomph" to capture the bolts. These were often fast and faint, with a blood red color buried in the rain and extreme humidity. And again, shutter means nothing. I hope people that didn't understand that do now.
Here is just another example of sky color at night with a long exposure. City and town lights do that. The parkinglot light that is illuminating that cross and waterdome is quite a ways away from here, and not very bright. In reality the bright areas were darker than these shadow areas in the image. Just a little bit of light can go a long ways with a long exposure. This was 204 seconds at F4 with ISO of 200. Here are a few chases with some more talk on lightning: July 25, 2006 Missouri River Lightning In general, you'll usually use 100 ISO with your lens pretty open. If you wind up near a close cg barrage, out of precip, you'll certainly want to be on 100 ISO and maybe stopped down to F18 or more. With digital and some understanding how the camera works, it is rediculously simple. Staying out of sprinkes is the hard part. If you don't have one you might consider getting a window clamp to mount the camera to your open window. It's been 2 years since I've used a tripod on a chase. It's probably been another 2 years before that time. My window clamp is right up there with my gps as far as favorite things to have with. It's so cheap it seems silly not to, unless you enjoy standing outside of the car around electricity that is able to jump several thousand feet.
Here is one just for a fairly close bolt example. It was about 1/4 mile away based on the flash boom gap on video. I'm at 17mm so it's a wide angle shot. The ISO was 100, which helped keep this close thing in check and the aperture was only down to F5.6, still pretty open. These weren't super bright staccato bolts(those are excessively bright usually and EXTREMELY short duration...fairly rare, certainly not common). They were fairly bright and were still very short duration. I guess that would be why even having it open to F5.6 still worked. That is fairly close, but it certainly isn't in the superclose realm. I know one chaser who captured a 3 channel bolt about 30 feet away. To give an idea how close it was it would be like this bolt hitting the tip of the T in my copyright in the bottom right, or at least not very much above it. He was using 100 ISO and stopped down to F22 at the time. That is the only reason it did not blow out. If this bolt here hit that close with the settings I was using, the whole image would most likely be white.
One more image. This was easily the hardest bolt I've ever got. First off, there were soooo few bolts showing themselves behind this line of storms(I'm looking east). By the time this one happend the line was waaaay east, with just some little weak "storms" going ne behind it. So getting anything was hard as it was. The biggest problem was the city, obviously. All these lights were limiting my exposure time. So you say, well you could stop down the lens so the shutter could be open longer. Well I could, but then when a bolt would happen, that stopped down lens would not work on it. The lightning needs what it needs. This was shot at F5 with ISO 100, that is pretty much what the lightning needed. So with those set to that, my shutter was down below 10 seconds to keep the city from blowing out. This was actually 8 seconds. Even that short at 8 seconds you can see some blowing out, like the Woodmen tower and some of the lights down Douglas Street. I was down there trying to get this shot for over 2 hours, 3.5 hours all together from being in the rain as the storms came in till I left. If one could just leave the shutter open for a long time it would not be a big deal. But doing mostly 10-15 second exposures for that long.......well believe me, it gets tiring. There was no choice though. Now if I had some super bright anvil crawler shooting out from behind the storms it would have been different. Then I maybe could have stopped the lens down some and let the shutter go longer. I actually finally got this one doing a "quick draw". I waited till the second I saw any flicker then pushed the button on the cable release. I'd gotten tired of filling up my flashcard with 10 second shots for nothing, then having to delete them(and of course missing lightning while I did so!.....I need a bigger flash card... mine was only 512mb at this time..I'll have a 2 gig one soon, if not 4).
All for now. I might add to it later or just make another entry. It all really is pretty simple, especially if one has a digital camera. |