# Do I need a light meter? Can I use Android or iPhone??



## omar (May 30, 2013)

I've been looking at 3 point lighting videos

All the experts use a light meter
If I want to be in full control, should I also invest in one?

I've seen them for about £30. Are there one or 2 models that are industry standard?

*AND*... how about Android or iPhone? I've seen a few apps for light meter
Are these a waste of time? Android I would be happy to dismiss
But iPhone... that always surprises me

Thanks


Omar


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## neuroanatomist (May 30, 2013)

Sekonic is probably closest to an industry standard.


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## awinphoto (May 30, 2013)

erm... if you're going to use the iphone/android for a light meter, screw it, use the in-camera meter... it will do the same thing. WHAT the iphone and android cannot do is spot meter, flash meter, incident meter, percentage of flash metering... etc. most in camera meters are probably as sophisticated as the iphone meters...


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## omar (May 30, 2013)

camera's own built in meter?
erm... i haven't got that far in the manual!
can u give me a 2 line description of what i need to look out for and how to use?
i'll read up from there

sekonic: £120 - £400
will i be 95% ok with a £30 cheap model?

thanks


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## wickidwombat (May 31, 2013)

dont waste your money just shoot a few frames adjust the lights to suit
with digital this is quicker than messing around with a light meter,
if shooting film on the other hand a light meter is very necessary all inthe studio of course
if none of this makes sense then you definatley dont need a light meter so dont waste your money


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## omar (May 31, 2013)

wickidwombat said:


> dont waste your money just shoot a few frames adjust the lights to suit
> with digital this is quicker than messing around with a light meter,
> if shooting film on the other hand a light meter is very necessary all inthe studio of course
> if none of this makes sense then you definatley dont need a light meter so dont waste your money


makes perfect sense 
i just thought it would be necessary to have the light meter, unless you had a really big monitor where you could see clearly the output of your shots?


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## Mt Spokane Photography (May 31, 2013)

omar said:


> camera's own built in meter?
> erm... i haven't got that far in the manual!
> can u give me a 2 line description of what i need to look out for and how to use?
> i'll read up from there
> ...


Your camera is going to be more accurate than a cheap model light meter. It is metering the light that is coming thru the lens. If you use a external meter, (a good one) , that's a good way to go, but there are pitfalls. 

For example, each lens loses some of the light entering it, so if you set the lens to f/2.8, for example, after the light loss, it might be f/2.6.
You need to know the "T" (transmission) stop for your lenses if you want to be as accurate as the in camera metering. Using a light meter correctly is a skill. Reading is a good way to start, but it takes a lot of practice to discover the many ways to go wrong.


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## jhaces (May 31, 2013)

Mt Spokane Photography said:


> For example, each lens loses some of the light entering it, so if you set the lens to f/2.8, for example, after the light loss, it might be f/2.6.
> You need to know the "T" (transmission) stop for your lenses if you want to be as accurate as the in camera metering.



Sorry, but it would actually be a larger number, so a f/2.8 lens, after light loss, would be an actual t/3.1. 

As for the parent, you should read up on what a histogram is and how to read it correctly, you'll benefit a lot from that and you'll be able to make do without a lightmeter for a while (unless, as it's been said, you do studio work). Read up on your camera what the exposimeter does and the different metering zones.


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## agierke (May 31, 2013)

if you dont know what your in camera light meter is then you shouldnt be buying a hand held meter. know how to use your current gear before buying new gear to fix problems you arent even aware of yet.

that being said....

incident meters are typically far more accurate than reflective meters. reflective meters can be fooled, incident meters will read exactly what the light is doing (assuming you use it correctly).

digital has made it easier to make available light exposures doing adjustments based on preview or histogram displays. i still find incident meters very useful in studio lighting scenarios if you are trying to fine tune the ratios of strobes. in camera meters cannot help with this technique and even tethered shooting will only offer the opportunity to "guess" at what your ratios are doing. a hand held incident meter is still very useful (and a time saver) for situations like this.

but again...if you don't know what your in camera meter is or how it works you are likely putting the proverbial cart in front of the horse by buying a hand held meter.


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## wickidwombat (May 31, 2013)

omar said:


> wickidwombat said:
> 
> 
> > dont waste your money just shoot a few frames adjust the lights to suit
> ...



2 important things to note
- have highlight alert enabled on the camera this is where blown highlights flash white and black this will show if your lights are too strong and you are clipping highlights
- keep an eye on the histogram

the picture itself is secondary to these on the screen when you are mainly concerned with getting your exposure correct


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## omar (May 31, 2013)

I just thought of something 
In the videos the guy was measuring the light on the wall and making sure it wasn't lower than the lights - if so he'd turn down the lights a stop or 2 - otherwise you get a dark background 
Then he also measured the back of the models head

So... All of this seemed to make sense to me and I assumed this was an essential part of photography? 

But you guys are saying I won't need for a long time - until I get much more professional? 
What am I missing? 

Just found the video of where I got all of this information :


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## omar (May 31, 2013)

Perfect lighting for a white background

I'm replying from my android phone. It was impossible to cut and paste that link !


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## agierke (May 31, 2013)

that video demonstrates working the ratios between multiple strobes in a studio set up. your cameras meter is near useless if you want to approach working your exposure like that. if you have the experience with meters and other such things like zone system then you can get by without a meter but if you want to maintain exact control over exposure while using multiple lights in a studio then meters are still necessary.

the video (as most online instructional videos do) assumes the viewer already understands how meters work. to use a meter to its full effect you really need to understand a couple of different things.

first, all meters measure light and give readings for middle grey (or what is sometimes called 18% grey). middle grey is the 5th zone in a 10 step grey scale which represents 10 equal steps from pure white to pure black. zone 5 (middle grey) is the average between pure white and pure black.

second, there are two types of meters...reflective meters and incident meters. reflective meters measure light bouncing off a subject while incident meters measure light falling on a subject. understanding the differences between how these two types of meters work is critical. reflective metering can be problematic at times because light reacts differently depending upon what subject it is bouncing off of. if you meter a white wall with a reflective meter and shoot it at the suggested settings you will get a grey wall. if you meter a black wall and shoot it at the suggested settings you will again get a grey wall. different subject tones will absorb different amounts of the light falling on it (thus giving us the perception of the wall being white or black) but a meter will always try to measure for middle grey, regardless of what the tone the subject is. incident meters forgo the problem of different tones absorbing light differently by measure the amount of light falling on the subject. measure a white wall with an incident meter and shoot at the suggested settings and you get a white wall. do the same with a black wall and you get a black wall.

additionally, reflective meters have several different ways that they will measure light coming through the lens. you will have to refer to your camera system to see the different modes available to you but they generally fall into the following categories:

evaluative: typically measures the entire scene and averages it out
center weighted: typically measures only a portion of the frame in the center and averages that portion
spot: only measures a small single spot in the center of the scene

each of these methods have their advantages and drawbacks depending on the tones present in the scene and the nature of the light you are trying to shoot in. to use these modes effectively you really need to have a very good understanding of different qualities of light and when a certain type of light combined with certain subjects will fool the meter and give less than ideal results. watching videos online or visiting forums wont provide this knowledge...only lots of shooting in various circumstances will provide the understanding you need.

finally, meters are just a tool to gather information to help you decide what your exposure settings should be. they do not tell you correct exposure. exposure is essentially a creative expression and no camera or meter (or electronic device) is capable of making creative decisions...that can only be done by a person. 

learn how your camera's meter works by shooting the heck out of it in different available light scenarios. this will strengthen your understanding of light and will inform you of how to approach different studio lighting setups. once you are in studio, an incident meter will be needed if you wish to maintain complete control over all your lights.


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## omar (Jun 1, 2013)

@agierke thank you for a most informative and wise reply. Your reply suggests that the video is a very dangerous one!? 
Since I appears to suggest everything is quite simple. When in actual fact, this is not the case and there is a lot more to it than just measuring left right and centre!


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## privatebydesign (Jun 1, 2013)

"The Zone System" the classic one that most people refer to, is an 11 level system not 10, everybody who doesn't use it but tries to teach it forgets Zone 0.

Zone 0 is black, Zone X (10) is white, Zones I-IX (1-9) are varying shades of grey.

http://en.wikipedia.org/wiki/Zone_System


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## omar (Jun 1, 2013)

Ok... I get that there's a precise science... 
But is there a super simple beginners guide? 
A fail safe step by step guide that will give you 95% good results without a £400 light meter? 
If not 95% what's the closest you can get through simple steps? 

Thanks


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## privatebydesign (Jun 1, 2013)

It 100% depends on what you are trying to achieve, what equipment you have and how accurate you need to be.

If your lights are the same make and have levels dials or bank switches then you can work out levels from them (or a tape measure!). If you are shooting multiple interviews at different locations, or scenes from different angles and you need continuity in light then a meter would be your best bet.

If you just want a pleasing look then you can wing it easily. If you want to work like a pro then a tape measure first and a lightmeter second.

If you want to wing it, set your background exposure so it just clips first (for a white background) then set your key light two stops lower, then set your fill one or two stops below that. You can guess the brightness by what your shadows are doing.


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## omar (Jun 1, 2013)

privatebydesign said:


> If you want to wing it, set your background exposure so it just clips first (for a white background) then set your key light two stops lower, then set your fill one or two stops below that. You can guess the brightness by what your shadows are doing.


thanks for the reply
how do i set the light to be x steps higher or lower?
is there a control for doing this on high end lights or something?
thanks


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## dirtcastle (Jun 1, 2013)

Start off by using in-camera metering and firing off test shots to get it dialed.

Once you reach the limit of that approach, then go to the next level.


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## chauncey (Jun 2, 2013)

I never could grasp the concept of lighting/exposure and whatnot so...I cheat by using manual mode and use the LCD histogram in live view.

Taking into consideration that the histogram is a jpeg rendition for the LCD screen, for RAW shooting you should neutralize your in-camera settings.
Open your RGB histograms in LV>dial in wanted/needed SS and f/stop and use your ISO setting to push that histogram to just shy of touching the right edge.
That location for the histogram is known as "exposing to the right", commonly thought to be proper exposure.

When that histogram encroaches off both the right and left edges, black dog in snow scenario, you have overwhelmed your dynamic range...maybe do HDR.


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## Halfrack (Jun 2, 2013)

So to answer the original question, both are a solid maybe. iPhone and Android based light meters can be used for constant lights - stuff you'd use to shoot video. Light meters that understand what a strobe is are worth their weight in gold, as it allows you to construct a photo, building an image in layers, and lighting each layer independently.

So the next question is if you need a light meter. Long story short it depends on what you're shooting. Light meters are used in fine art and portraiture, mostly when using strobes. If you do this style of photography AND you are doing off camera flash, then it would be a good idea to pick up a light meter. Otherwise, save your money.


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## docholliday (Jun 2, 2013)

A real meter offers something that an iPhone or android box can't - repeatability. The whole point of a real, calibrated meter is to insure consistency shot to shot. Your in-camera meter will do more than any phone will. Using a histogram is only good for verifying the shot, and will only show exposure truly correct if the whole frame consists of mostly midtones. Having a lot of sky will push the histogram more one way and having a lot of shadows will push it the other - not the proper tool for determining exposure, but for verifying that you have given the most info you can to the sensor without going outside the limits.

Why not pick up a good, used meter, such as the Sekonic L-328 and learn the concepts of photography - light control? You can get the 328 for under $100, with the incident dome, and be able to do still, cine, and strobe. There's also the Minolta AutoMeter IIIF for around $50. Somewhere like KEH http://www.keh.com/Camera/format-Accessories/system-Light-Meters/category-Light-and-Exposure-Meters?s=1&bcode=GM&ccode=70&cc=80576&r=WG&fwould be a good place to start.

Then, pick up a cheap beginner's book on photography and learn something like the SLAT (SL=AT) relationship and you'll be doing more than randomly firing off shots trying to "dial-in" proper exposure. What looks right at the time of exposure on your tiny little view screen to your eyes may not actually be proper, you may be off by 1-2 stops - which will be enough to destroy shadow or highlight detail (Zones 1-2 and 8-9). Not to mention the needless number of wasted exposures and time and will piss you off when you get to editing and realize that you can't push the recover/highlight slider in Lightroom far enough to get back the detail you saw when you shot it.


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## Adrian2 (Jan 11, 2015)

Halfrack said:


> So to answer the original question, both are a solid maybe. iPhone and Android based light meters can be used for constant lights - stuff you'd use to shoot video. Light meters that understand what a strobe is are worth their weight in gold, as it allows you to construct a photo, building an image in layers, and lighting each layer independently.



Time is passed and things are changed. Now you can plug a simple add-on sensor in your smartphone and turn it into a high performance light/flash meter. Here are two examples:

- http://www.lu.mu/lightmeter/
- http://www.optivelox.com/app_en/lxmeter.htm


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