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The Beginners Guide (Reference Only)
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It has been requested by the admin team that this thread be put in this section for people to be able to see and use as a reference material. It will be locked, but if you wish to read the replies and/or put your own views forward please refer to:

http://fox2.co.uk/viewtopic.php?t=4157

So, On with the article

Well a fair few of you requested one, so today myself and Simon (Viper28) took up your challenge and have come up with this. Please note that we have both written different peices of this so when we refer to "I" it is sometimes me or Simon.  Good

So where do we start. Let’s assume that you are a total beginner to the vast world of Low Level Photography.

So, you have got the location info, you have struggled up the top and worked out which direction the aircraft will be coming from and you have got yourself set ready and waiting. Next question is “what settings should I use on my camera?”

Now if you’re reading this on your iphone already up the hill or just want a simple answer then here it is:

1. ISO: 400
2. Camera Mode: Shutter-speed Priority (Tv)
Shutter Speed: 1/1250th Second (Jets) / 1/250th (Props)
3. Focus Points: Nikon Dynamic AF / Canon All Active
4. Auto Focus Mode: Continuous (AI Serv)
5. Drive Mode: Multi Shot
6. Metering Mode: Matrix / Canon Evaluative
7. File Format: Large JPEG
8. White Balance: Auto (AWB)

Those generic settings should give you a good image of any aircraft that comes low level in most weather conditions you want to be out in.

We will now spend the next 2500 to 3000 words explaining how we came to that condensed set of values, why there are not optimum and how you might want to change them. In doing this we are going to assume that you are using one of the low to medium end camera bodies (so typically Canon 400D to 7D and Nikon D1000 to D300). If you are lucky enough to own a professional body like a Canon 1-Series or Nikon D3 we are going to assume you know how to configure its advanced features!

The rest of the discussion will be Nikon / Canon bias because the two authors know them best. That said the concepts (if not specific named settings) apply to Sony, Pentax and any other D-SLR body just as well.

1) ISO Settings (Starting Recommendation ISO400)
The ISO setting on a digital camera basically determines how sensitive to light the camera’s sensor is. The higher the ISO number the more sensitive and darker light you can take pictures in. However, there is a trade off, higher ISO sensitivity means higher “noise” or grain effect in the picture which will affect the image quality and detail. The aim then is to keep the ISO value as low as possible. As a starter value we have recommended ISO400. This is right in the sweet spot for the majority of our target cameras. Nikons are probably happier to go more towards ISO800 with little noticeable noise, Canon’s closer the ISO400. The ISO speed will have a direct influence on the Shutter-speed you can use, the higher the ISO the higher the shutter-speed.

This said take a look around at the light and the weather. If it's a really bright sunny day then try to lower the ISO down to ISO200 (or even ISO100 on a Canon). Every ISO stop lower than ISO400 you can get (while still maintaining your target shutter-speed) the cleaner your images will be.

Some cameras at this level have simple AUTO ISO settings. With these you are going to set your target shutter-speed (and) or aperture and the camera will decide the ISO that gives you that. On a Nikon body we would generally advise avoiding setting the ISO to Auto. This is because, as far as we know, my camera does not have a function to set an upper limit. Thus you could accidently find myself shooting at f/8 @ 1/1250th but at ISO3200! Not good. Canon’s implementation of AUTO ISO is actually more restrictive generally limiting the ISO range selected from ISO200 to ISO800 in most modes. This therefore puts it in our ideal ISO range although it does have a tendency to go for the higher settings.

2) Camera Mode (Recommendation Shutter-Priority)
All the cameras discussed have multiple operation modes available to them but the two most common ones used for low level photography are Shutter-Priority (Tv) and Aperture Priority (Av), the use of which divides photographers down the middle.

What’s the difference I hear you ask?

Shutter Priority (Tv): Is a function where you can set the shutter speed that you wish to use on any given pass and the camera will adjust the aperture value according to the amount of light available, and the ISO sensitivity you set in Section-1.
Aperture Priority (Av): Is a function whereby the user selects the aperture (f-Stop) that they want to use and the camera will automatically adjust the shutter speed according to the amount of light that is available.

There are pros and cons to both settings but in general we are going to recommend that you start with Shutter-Priority. The reason for this is it's generally easier to set and predict what the camera is going to do. One of the most disheartening things for a newbie is either an out of focus (covered later) or “shakey” blurred picture. No amount of post processing will correct that, where as exposure problems, to a certain extent, can be corrected. In the later cases this is caused either by a shutter-speed being too slow for the speed of the object or because the speed is too slow to damp out shake in the lens caused by you. For jets this is fairly easy to control in Shutter-priority, simply set the speed to 1/1000th and 1/1600th of a second (we recommended 1/1250th right in the middle). This is fast enough to “freeze” any jet you will see low level and is higher enough to avoid camera shake (which should be isolated at around 1/750th sec on a 300mm lens).

Prop planes (like a Tucano or Hercules) are not as fast but shutter-priority solves another problem with them – prop blur. This is something you actually want but actually requires a slower shutter-speed as 1/1000th second will stop the props dead, giving a very unnatural look. Ideally, you are going to want a shutter-speed of 1/250th sec or less to give prop blur. This however comes with a health warning as that speed will drop you right back into the camera shake zone on any telephoto lens without VC / IS.

Shutter-priority is not without its issues however. The only way the camera can meet your shutter-speed requirement is to adjust the lens aperture. It will do that until it can open the lens no further at which point the camera will probably warn your but will continue to take under exposed pictures. Avoiding this situation is one of the reasons we have recommended a relatively high starting ISO.

Also the biggest gotcha with shutter priority is forgetting to set it back from prop to jet! I’ve lost count of the times I’ve done that. I try to leave mine on a Jet setting and change it when I see a prop job coming round the corner (lets face it you have plenty of time to change it with a Herc!).

This is also one of the reasons some photographers choose to use Aperture priority (Av) relying on there camera (particularly panning) skills to make up for that’s modes danger of low shutter-speeds.

Other photographers will mix and match setting the camera to Aperture priority for jets and Shutter Priority for props. Switching between the two then just needs a twist of the control dial.

So far the topics we have discussed are fairly standard across the makes and the recommendations hopefully not too controversial, the following however are far more make and model related and more personal, probably representing the settings you will modify first.

3) Autofocus Mode (Recommendation Continuous (AI-Serv))
Nikon call it Continuous, Canon call it AI-Serv, regardless of the name this is the one and only mode you should use for low level photography.

Basically, 99% of d-SLR’s can only focus on an object when the mirror is down and you are not actually taking a shot. With fast moving objects (like a jet) the camera actually therefore needs to “predict” where it will be when you actually take the shot and that’s what these modes do. Basically, as you focus on the plane the system tracks it and calculates it's direction and speed. It can then determine where it needs to fore or back focus as you take the shot.

4) Autofocus Point Selection (Recommendation All Points)
Now comes the tricky bit as the options available these vary considerably between the two makes. If you have a Nikon, they will all have three AF Point modes:
Single Point AF: This is as it suggests. AF is acquired from the single point that you nominate to be the single AF point. No other AF point will be used.
Dynamic Area AF: This is a natty little function that Nikon have installed. Nikon give you the chance to use a Single Point of your choice but also give you the back up of “activating” a fixed/chosen (depending which camera you have) amount of surrounding AF points. What this helps with is if the subject you are panning with wanders out of the AF point you have selected one of the other “activated” AF points will detect the object and lock onto it until it returns to the original place.
Closest Subject: Again, as the name suggests the camera will focus on the closest subject in the frame. Beware using this mode as I have found on experimenting that it does sometimes have a tendency of “Hunting”

Now comes the first part of potentially confusing stuff.
Remember the Dynamic Area AF? Well you may be lucky enough to have a camera that lets you choose the amount “activated” points in that setting. Personally I can choose from 9, 21 and 51.
So you obviously use the most you can don’t you? Not necessarily. The more you are asking the camera to do the slower it will do it. You may not notice this with the eye as you are taking the shots, but the results will be in the shot. The less you ask of the camera to do with it’s processing power the more efficiently the camera will work all the various functions it is managing (Focusing the Lens, Shutter activation, recording the image, AF etc etc….)
I will generally flit from 9 and 21 point depending on how my panning is performing on the day. It is your choice to see what works for you. Try all points activated until you get used to the gear and then you can start fettling with the settings once you are comfy.
If your camera does not have this option to choose the amount of AF points, ignore everything in the last paragraph EXCEPT the bit about the processor, I will return to it later.  

With Canon, unless you have a 7D, you will be limited to 2 choices, All Points or Single Point.
Single point works much the same as Nikons. You choose one of the nine points (usually the centre one) and this is the only point the will be used for focus. The problem with this is, if you move that point off the subject (or it looses contrast to focus on) the focus will hunt until it regains lock.
The alternative, with the Canon 9-point AF system, is to activate all points. This is my preference, as in AI-Serv mode what this actually does is obtain focus lock with the centre point and then continue to use that point unless lock is lost. If focus lock is lost, it will switch to the next closest point that has lock. This can avoid hunting situations.

If you have a 7D then you have two more useful options. Assist points and zones. Simply put Assist points allow you to choose a single point but let the camera utilise the immediately adjacent points to “assist” that point in maintaining focus lock. Zone is similar to the Nikon Dynamic Area and consists of a group of AF points (9 in the case of the centre group) any of which can be used to maintain focus on the plan. On the 7D I’d probably choose the centre zone but I’m still playing with it.

First time out I’m going to say, regardless of make / model more points is going to give you more latitude. As you get use to tracking the jets, then you can consider reducing the number of points in use.

5) Drive Mode (Recommendation Continuous Shooting)
In general, you are going to go with continuous here. This means as long as you hold the shutter down it's going to take pictures – up to a point. That point is the camera memory buffer being full. At that point the camera will have to de-stage the pictures you have taken and write them to the memory card. At that point picture taking drops from Frames Per Second (FPS) to Seconds Per Frame. The point that happens will vary by the camera and the type of file your taking (JPEG/RAW) – when it does happen it's damn annoying!

Some cameras give you the option to select the speed of the FPS that is delivered. Now there are Pro’s and Con’s with fast and slow which are generally personal preference. Some say that just Machine Gunning the aircraft down is not very skilful, but let’s face it, if you have never been up the hills and get an Eagle as your first aircraft you may want to get as many shots off as possible to maximise your chances of getting “that shot”.
Again, for Nikon’s (but im sure for other camera makes as well) there is a case in point that the less you ask the camera to perform the better the performance of the camera. I will explain;
my camera is capable of 7FPS on continuous shooting. It also gives me the choice to have the FPS as anything from 1 – 7. It was suggested to me one day when I was complaining about the amount of “keepers” I was getting from a pass to reduce from 7FPS to 5FPS (and the above mentioned AF points). The idea in this was not to overload the cameras processor so that it can still take the shots at a reasonable frame rate but not taking too much processing power away from the AF (what’s the point in having a fast AF lens if the camera can’t tell it to work?)
Also, in the FPS being lower, it means that the shutter is up for less time, thus meaning you can see through the view finder more, thus keeping the panning more on target.
In general using around 5-FPS and triggering bursts of around 5-frames works well as a compromise of allowing the camera to de-stage effectively and maintaining your “sight” through the viewfinder.

6. Metering Mode (Recommendation Nikon Matrix / Canon Evaluative)
Nothing will split the low fly photographer community like the question of which metering mode to use. It's probably the setting that you are most likely to play with. Once again Canon and Nikon have different names for essentially the same thing. But the most common ones are:
Matrix / Evaluative: The metering system on the camera is split into a number of segments (the number varies considerably generally the better the camera the more segments). The camera evaluates the light in each segment (often with help from the AF) and works out the exposure based on the subject. This is highly effective in most situations and the mode we recommend you start with certainly with a Canon.
Partial: The exposure is based on the central portion of the viewfinder (or the active focus point for Nikons). Typically this is around 10-12% of the total viewfinder. In theory this should be ideal for a plane provided you keep it in the metering area, not so easy with a Canon.
Spot: Like Partial but only uses about 2% of the focus area. I consider this one lethal for anyone but very experienced low level photographer because at that level of sample putting the point on a roundel or cockpit glass will totally throw the exposure.
Centre Weighted Average: This is actually a bit of a throw back to film cameras and biases the exposure to the centre of the frame. Because this is (hopefully) where the plane is, it's actually a pretty good choice.

This is probably also a good point to mention the exposure histogram and exposure compensation. All d-SLR’s have the ability to display, when previewing your shot an exposure histogram. This shows you how the picture is exposed. In general readings to the left of the graph are dark, to the right light. It goes without saying you are trying to get the majority of the reading in the middle. You are highly recommended to find out how to display the histogram (on a Canon you press the INFO button when reviewing the shot) and learn how to read it.

When you have mastered the histogram (or if your shots are obviously too light or dark) then you can consider overriding the metering using Exposure Compensation. This basically takes the reading calculated by the metering system and then overrides it by a given value. Consult your manual on how to do this for your camera but remember a little goes a long way/ +/- 1/3rd a stop makes a big difference. Negative compensation will make the plane darker and positive compensation lighter.

7) File Format (Recommendation Large JPEG)
Now what I really wanted to say here was RAW but I went with JPEG. You will most likely end- up shooting RAW in the future but for a first trip I’ve plummet for JPEG for two reasons. First, if your reading this I’m making the assumption that you are fairly new to photography and there for do not do a lot of post processing of your shots. RAW forces you to post process. Large JPEG still contains enough information to crop and make moderate adjustments to exposure if you need too. Secondly is the buffer issue mentioned earlier. Shooting JPEG you can take x3 to x4 times as many shots than RAW before you hit the buffer full condition. In reality, that means you probably won’t hit it.

Ultimately, after a few trips you will probably find that you actually “machine gun” it less and RAW becomes a more viable option. RAW (sometimes called “digital negative”) is actually the data more or less as it comes off the camera sensor that you have full access to change in post processing. This is distinctly different to JPEG that is processed in the camera and certain values (like white balance) fixed. Basically, raw allows you to correct many more exposure issues in post processing.

8 ) White Balance (Recommendation Auto (AWB))
I’m not going to say much about this one, just leave it in Auto (AWB). OK, it's a measure of how “hot” the light is and is a Kelvin (K) value of how bright 20% grey is. Told you, leave it in auto, most camera’s are pretty accurate in daylight using AWB (artificial light is another matter).

Right, hopefully if you got to this point, you understand a little bit more about how your camera operates and how to set it up for low level photography. As I’ve already said, the settings we recommended are very much starters, use them and there will be nothing fundamentally wrong to stop you taking great pictures. They are however there to get you start, experiment and please ask any of the guys on the hill most are only to pleased to offer advice on how to set up your camera.

We hope that this has been of some help.

Cheers

Pete & Simon

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