An Idea, LED Modeling Lights in Speedlight Flashes

For the last year or so I’ve been talking about features I’d love to see implemented in camera gear. This time I want to talk about having a proper continuous modeling light built into a hotshot flash.

Before I get into the meat of my idea, the first question one might ask is simply, what’s my problem with the status quo?

After all, most hotshoe flashes in addition to being a flash, have some form of modeling capability (by strobing the flash tube) along with some form of autofocus assist capability (typically with red or near-IR LEDs). After all they do provide the intended functionality to a large degree.

So what does having an actual LED modeling light enable that having IR autofocus LEDs or strobing the flash tube doesn’t?

I have two main use cases where I think this would be a beneficial idea. First is for people who need to shoot video. Specifically I’m thinking about photojournalists, who are increasingly being asked to get video clips for their publication’s website, but the idea applies elsewhere too. With things as they are now, you ideally need a speed light for stills in a wide range of conditions, and a separate video light of some sort — at least potentially — for video. With my idea, you’d just have your speed light.

The second case where I think it would be useful is in strait up using speed lights as a replacement for studio strobes. Admittedly this is also a personal point for me. I have nothing against studio strobes, I just never went down that path. However, I do a lot of product photography for this site, where I use speed lights in various modifiers (e.g., the Lastolite EzBox Hotshoe).

The thing with studio shooting is that you don’t want ambient light contaminating the colors in the images you make. That means generally you keep the studio dark so the only light comes from the strobes themselves. With speed lights, that also means you don’t have much if any light illuminating the subject matter for focusing and composition.

Okay, so clearly the idea here is that I’d like to see a continuous LED modeling light in a flash. Canon already did something kind of like this in their Speedlite 320 Ex. Well except not really. Yes, they put an LED on the light, but it’s not integrated with the zoom head, so it doesn’t actually model what the flash would do. Moreover, as far as I know it doesn’t track flash power, or have any kind of power adjustment at all.

What I’m envisioning is integrating the LEDs into the flash head in the same area as the flash tube. Perhaps off to a side or both sides. This would then allow the LEDs to use the same zoom head, and therefore mirror the behavior of output of the flash tube.

Moreover, I would want them to be able to track the power output of the flash as well. If you’re going to do modeling lights, you should at least be able to see what the ratios will look light too.

Okay, so let me wrap this up with a bit of back of the napkin engineering.

I don’t see why a high power LED or two couldn’t be put in the flash head. The issues are mounting location, heat, power consumption, and brightness. I’m not going to comment on mounting since I’ve not spent any time digging around in the zoom head of a flash.

Heat, power consumption, and brightness are all related. The brighter the light is the more power it draws and the more heat it dissipates. An LED like the Cree XP-G2 can produce 172 lm/W and can be driven at up to 5W (for a max of 586 lm output). A reasonably good set of 4 NiMH AA batteries can provide up to 12 Wh. So some quick math says a single XP-G2 LED running off 4 NiMH batteries worth of energy could deliver 172 lm for 12 hours, or 586 lm for a bit more than 2 hours. Of course, the trick/trouble with driving the LED at 5W would be dissipating the heat it produces.

One up side, since the LEDs don’t produce infrared light (i.e., heat) there shouldn’t be much concern in overheating and melting the plastic Fresnel lens elements in the zoom head. The only heat concern is how to safely dissipate the heat of the LED itself.

Anyway, I’ll leave the actual engineering for the camera makers, I don’t think I’ll be trying to hack LEDs into my 600Ex-RT anytime soon. But it would be nice to have.

Hands on First Impressions with the 5D mark IV Podcast Ep. 10

Image: Canon USA

Hands on first impressions of the 5D mark IV (download MP3)

I got my hands on my 5D mark IV much sooner than I had ever expected. These are my first impressions with the camera. I’m not going to write a long post here, like I did in last weeks episode, since I’m getting into actual review territory. However, suffice to say, the 5D mark IV is, in my opinion, very much a significant improvement over Canon’s previous products.

Backing up your Photos and Data

This is a drum that bears beating as often as possible.

Backup your data.

I was reminded of this point again recently, when a friends granddaughter lost all, or at least most, of her collage school work and pictures when the drive in laptop died. And with no backups, I don’t even want to think about what that must have been like for her.

In my experience when I’ve done IT consulting work in the past, backups are one of the first things that get overlooked, ignored, or forgotten about. This is even more true, when the backup requires some level of user interaction.

Proving my point, when I mentioned the above incident to my parents, my mom realized that she wasn’t backing up her computer at work. When it was setup, it was setup so that it could be backed up, but the act of plugging in a USB stick and running the backup command… Well, lets just say it got lost in the cracks.

At the same time, backups need to be taken offline to be truly safe. If you’re backing up to say USB disk, and it’s still connected to the computer, the chance is always there that you might accidentally delete it. Or that one of the crypto ransom viruses, could encrypt it rendering it useless. Moreover, if the backup disk is still attached to power, there’s always the possibility that a power surge or lightning strike could destroy it.

In short, if the disk is plugged in; it’s not a good backup since it could be erased or killed by a power surge. But if the disk is left unplugged, then the act of having to plug it in becomes a hurdle to getting people to actually back things up.

Ultimately, I have 3 points in writing this.

  1. Remind people to backup their data
  2. Remind people that are backing up their data to make sure their backups are actually working
  3. For those that aren’t backing up their data offer up some options that they might find useful to start backing up their data.

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My Thoughts on the Canon 5D mark IV Podcast Ep. 8

Image: Canon USA

Thoughts on the new Canon EOS 5D mark IV (Mp3)

Discussion

For the past couple of years, I’ve posted articles talking about my impressions about most higher end camera. This time I’ll be doing this both as a text post and as a podcast. These notes are not exactly a summary of the podcast, but they should be close. I’m actually writing this independently of recording, not transcribing my recording.

I don’t get early hardware from any manufacturer, so this is mostly my impressions based on past experiences and published specifications.

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Canon EOS M3 Podcast Ep 7

Canon EOS M3 (download MP3)

Canon’s EOS M3 is not a new camera, at this point it’s a year and a half old, but it is new to me. These are my thoughts on my first impressions with the camera. I’ve only had one for a couple of days now, so this isn’t a detailed review. That said, my early impressions are that I really like this camera.

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Focal Lengths Podcast Ep 6

Download Episode 6 – Focal Length (MP3)

The question came up recently about focal lengths and crop cameras, and that reminded me of an old article I wrote talking about focal length being usually used as a proxy for angle of view. In this episode, I revisit the idea of focal length, the plurality of definitions that the word has taken on (both the optical engineering and photographic ideas), and how I think that’s comet to be.

An Idea, Camera Makers Should Provide Performance Data

A couple of weeks ago, when I was talking about the D500 again, I started to develop the idea that we photographers should be demanding more from the companies the make our cameras. At that time I was just thinking about quality standards. That got me thinking. Better quality is great, but you still need to understand how the camera behaves to use it optimally.

When digital sensors replaced film, the cameras became more than just a vessel to hold the image forming material. They literally became the film too. Yet when this transition happened, we lost information that we previously had at our disposal too.

If you’ve never shot film, or at least seriously investigated it, you’ve probably never seen the graphs below.

Excerpt from the Kodachrome 64 datasheet

These graphs are the characteristic curves for a piece of film, in this case Kodak’s now discontinued Kodachrome 64. More importantly they tell you almost everything you could want to know about the film and it’s capabilities.

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