I've been thinking recently a lot about light – without light, there's no photography or video (stating the obvious LOL). But also in relation to photography and video, I've been wanting to learn more about proper metering and trying out light meters.
Then I stumbled into this older article written by Ryan E Walters about using an iPhone as a meter and I was surprised by his findings. To find out his answers, you'll have to read his article.
But in the meantime, I'm still thinking about really learning more about metering regardless of whether it is with a phone or a Sekonic
Can You Really Use A Light Meter App?
If you have been following my blog for any length of time, you have probably picked up on the fact that I am a big fan and proponent of using a light meter. With Sekonic's release of the Sekonic 478D they increased the functionality of what a meter can do and made it more affordable. But what if you don't have $389? Can a free light meter app, or one that costs $4.99, do the job? That's what I set out to explore and the answer may surprise you.
Quick Reality Check
While the apps I tested cost next to nothing, let's not fool ourselves into thinking that they are really that inexpensive. As of this writing, they both require a $549 dongle. (Otherwise known as an iPhone). The cost of the dongle can be subsidized by paying for a phone contract, but it is a real part of the total cost, albeit a hidden one. If you are considering buying an iPhone to use as a light meter, I'd recommend saving yourself some money and buy the 478D. If, on the other hand, like many of us in the film community, you already have an iPhone, then the negligible added cost of these apps may be worth it to you, if you like the results that follow. 🙂
The Studio Results
First up the Sekonic meters:
If you are wondering why the incident and spot readings of the 758Cine are different by 6/10's of a stop, it has to do with the way mid tone is calculated. If you want to learn more about it, you can do so here. The spot meter of the 478D is 5 degrees; it sees a wider field of view than the 1 degree of 758Cine. That means it is averaging more information, which results in a smaller difference in this application. The results from these readings say I should expose at F4 using a 180 degree shutter, EI 1250, and shooting at 24 frames a second.
Read full article at Ryan E. Walters' blog “Can You Really Use A Light Meter App?”
|Note: it is our policy to give credit as well as deserved traffic to our news sources – so we don't repost the entire article – sorry, I know you want the juicy bits, but I feel it is only fair that their site get the traffic and besides, you just might make a new friend and find an advertiser that has something you've never seen before|
(cover photo credit: snap from Ryan E. Walters' blog)