Equipment Making continuous lighting [SURVEY]

Hi everyone. I'm a Design and Technology student two years (hopefully) away from university in the UK. My design brief is to make a light, and being a photographer and videographer, I immediately thought of a light for photos and video. It'll be a continuous light, because making a strobe requires a lot of specialist knowledge. I've posted this in a couple of other places (twice on Reddit) but I've had very few responses - the photo and video community on Reddit isn't very friendly. I'm hoping I'll get a few more responses on here.

I've narrowed my target market down to "the large market of amateur photographers and videographers who are searching for a cheap, high quality continuous lighting solution. They do not have the income necessary to invest in expensive lighting solutions, and lack the expertise or tools to make their own." I know this does not apply to a lot of you, but I hope you'll find you can still answer the questions.

I've also made my brief more specific than just "a light":
"I am going to make a light for photography and videography which will be adjustable (in terms of light intensity and surface area), safe in normal use (hot parts should be hidden but ventilated, and it should be stable) and provide enough light to use as a main light for photography or videography. It must also be cheap enough to produce as my client cannot afford expensive lighting. It does not to be extremely portable as it will be for studio use." If you need any clarification about this brief please ask, as it may be something I need to add to my project.

So here's the questionnaire. Could you answer in a format like "1(a), 2(a), 3(a)" or similar please?
Due to some people's security concerns in other places I've posted the survey, I've hosted the survey on SurveyMonkey. I had to split it into multiple surveys due to the 10 question limit. Please do the survey either here or on SurveyMonkey, not both. Thank you. The first part of the survey is here and the second is here.

1. How old are you?
(a) <20 (b) 20-24 (c) 25-29 (d) 30-34 (e) 35-39 (f) 40-44 (g) 45+

2. What is your primary occupation?
______________________________

3. Are you a photographer or videographer?
(a) Photographer (b) Videographer (c) Both (d) Neither

4. Have you used continuous lighting in the past?
(a) Yes (b) No

If yes: 4.1. Did you use any light modifiers (reflectors, softboxes, gels, etc) with it?
(a) Yes (b) No

If yes: 4.1.1 Which light modifers did you use? (say more than one if necessary)
(a) Softbox/other light softening (b) Reflector (built into the light or otherwise) (c) Gels or colour filters (d) Flag/other light blocking (e) Other (please specify) ______________

5. Are you currently in the market for continuous lighting?
(a) Yes (b) No

6. How much would you be willing to pay for a single, 300-500W equivalent light head?
(a) Under £50 (b) £50-99 (c) £100-149 (d) £150-199 (e) £200-249 (f) £250+

7. Would you prefer the light had an optional attachable reflector or a built-in one?
(a) Optional (b) Built-in

8. What would be your primary choice of subject when using the light? (eg portraits, still life, etc)
____________________

9. Would you want it to be daylight balanced so it can be mixed with sunlight, or does that not matter to you?
(a) I would like it daylight balanced (b) I do not mind (c) I would not like it daylight balanced

10. Please list any photography or videography information services you use (ie magazines, websites, etc)
_____________________

11. What finish would you like the product to have?
(a) Matte (dull) (b) Gloss (shiny) (c) No preference (d) Other (please specify below) ____________

12. Would a carry handle on the light be useful to you?
(a) Yes (b) No (c) Maybe

13. Do you have a preference for the type of bulb used? (say multiple if necessary)
(a) Incandescent (b) Halogen (c) Fluorescent (d) Compact Fluorescent (e) LED (f) No preference

14. What would be your preferred material for most of the light to be made of? (say multiple if necessary)
(a) Metal (b) Plastic (c) Wood (d) No preference

Thanks for your help. Feel free to ask questions if you think anything needs clarification - as I said before it could help me greatly. I'm planning on keeping you posted on my progress throughout the design process (probably in the Modding section), and hopefully end up with some video showing the effect of the finished product.

Thank you for your time.

 

I'll bite...

1. How old are you?
(c) 25-29

2. What is your primary occupation?
Student

3. Are you a photographer or videographer?
(a) Photographer

4. Have you used continuous lighting in the past?
(a) Yes

If yes: 4.1. Did you use any light modifiers (reflectors, softboxes, gels, etc) with it?
(a) Yes

If yes: 4.1.1 Which light modifers did you use? (say more than one if necessary)
(a) Softbox/other light softening
(b) Reflector (built into the light or otherwise)

5. Are you currently in the market for continuous lighting?
(b) No

6. How much would you be willing to pay for a single, 300-500W equivalent light head?
(b) £50-99

7. Would you prefer the light had an optional attachable reflector or a built-in one?
(a) Optional

8. What would be your primary choice of subject when using the light? (eg portraits, still life, etc)
Event photography, portrait

9. Would you want it to be daylight balanced so it can be mixed with sunlight, or does that not matter to you?
(b) I do not mind

10. Please list any photography or videography information services you use (ie magazines, websites, etc)
- Luminous Landscape
- DPreview
- Cambridge in Colour
- Practical Photography Magazine
- British Journal of Photography

11. What finish would you like the product to have?
(c) No preference

12. Would a carry handle on the light be useful to you?
(a) Yes

13. Do you have a preference for the type of bulb used? (say multiple if necessary)
(d) Compact Fluorescent
(e) LED

14. What would be your preferred material for most of the light to be made of? (say multiple if necessary)
(a) Metal
(b) Plastic


On a side note... good luck with your design brief but this is a heavily competitive and saturated market with several "known heavy hitters" already in this type of segment offering competitively priced products. It might seem a bit redundant to work on a project like this- and considering the price of LEDs is dropping sharply, their light weight, and low power draw- it's pretty much inevitable that they will dominate the market and be used in conjunction with gel filters or soft-boxes. I've purchased some hilariously cheap and ridiculously powerful LED bulbs- for example a 100 watt equivalent LED (standard socket insert) at Costco - 4 pack for $12.00 and they haven't stopped working yet (~2 years now).

 

In the sense of still you'll have a hard time to get anyone to bite in terms of constant as there is just not enough power or colour consistancy with cheap lights of which that is where your heading, video is alot more forgiving but the other thing you need to consider for video is that alot of videographers want portable or easily portable lights as more people are now shooting on location.


I think you've picked a hard market to get into but it'll be good to see what you come up with but I'm thinking it'll either be on par with the chinese crap that ebay is saturated with or it'll be LED based and extremely weak.

 

The LEDs I use must be used with a reflector to avoid eye damage from the power and bulb. LEDs have come that far, and have dropped that much in price.

 

Jasio, thanks for the reply. I appreciate it a lot. As for your comment at the end, fortunately I'm not planning on marketing this (except as a bespoke product - unlikely). It just has to sound like a viable idea to the exam board and my teachers. They don't do market research themselves to see whether an idea would be sellable.

M_D_K, you also raise some good points. A good daylight balanced colour temperature is what I'm aiming for, but fortunately I'm only making one unit so consistency isn't a problem as long as I can get this one right.

Build quality-wise, I think (hope) it'll be better than chinese crap on eBay, given that my GCSE project was an indestructible 3kg lump of steel (barbeque). I'm definitely aiming for good build quality - my main aims are really large light output (for a continuous light at least), build quality and colour temperature.

M_D_K's point about LEDs being weak is fairly valid - even if they damage your eyes while looking at them, they're still pretty weak compared to studio strobes. That's what understood from it anyway. From my survey results, it looks like LEDs and halogen lights are what's coming through. Halogen bulbs will probably need cooling, which is fine as it looks like I'll be putting a microcontroller in there (safe, low voltage switches and the ability to have a remote, something suggested by someone on Reddit).

 

A few things to keep in mind- LED's can be built up into arrays to improve light output. They generally output pretty cool white light so it's quite easy to fiddle with light temperature using filters.

While halogens have nice output and are cheap- they have two major draw backs that keep me from touching them: 1) Heat output (when on the move, the last thing I want to deal with is accidentally touching a hot surface when I have to go to the next event shoot). 2) Power. Halogens are high wattage, high power draw and I cannot always be guaranteed a local 110/220v outlet (or several). Nor can I always have wires- especially in convention halls of several thousand people milling around. On the flip-side, my LED lights will run on regular 1.5v 'AA' batteries all day long.

I will generally rely on LED for fill lighting (particularly behind individuals) and use flash strobes. In this case, I shoot Nikon and use an SB-910 as my commander/main flash or an SU-800 command unit, which then wirelessly triggers SB-700 flashes that are mounted on regular tripods with a reflector umbrella kit (these inexpensive kits clamp onto any standard tripod turning it into a reflector + strobe). It allows me to carry half as much light equipment because I can use the same tripod for portrait use, or take the camera off and mount a flash strobe + reflector in place without any real assembly. I can usually setup 2-3 strobes in this manner in around 5 minutes and have it ready it go.

Give me something that will mount on a bone-stock tripod Arca-Swiss plate- now that might pique my interest quite a bit more.

 

Lots of still life photographers use constant. I agree though.. not as popular as it used to be.

 

have you seen the manfrotto offering?

http://www.google.co.uk/products/ca...a=X&ei=F0dzUNXiIYGk4gTD84DwCg&ved=0CGAQ8wIwBQ

 

I'm unlikely to *really* need or want continuous lighting but in the interest of helping out

1 (b)
2 Journalist
3 (a)
4 (b) No
5 (b)
6 (e)
7 (b)
8 Mostly products photography, some portraiture.
9 (a)
10 Reddit
11 (a)
12 (c)
13 (f)
14 (a)

 

1. How old are you?
(c) 25-29

2. What is your primary occupation?
Wedding & Event Photographer/Videographer

3. Are you a photographer or videographer?
(b) Videographer for this case but I do both almost 50/50 this year

4. Have you used continuous lighting in the past?
(a) Yes

If yes: 4.1. Did you use any light modifiers (reflectors, softboxes, gels, etc) with it?
(a) Yes

If yes: 4.1.1 Which light modifers did you use? (say more than one if necessary)
(a) Softbox/other light softening
(b) Reflector (built into the light or otherwise)

5. Are you currently in the market for continuous lighting?
(b) Yes

6. How much would you be willing to pay for a single, 300-500W equivalent light head?
Have not done research

7. Would you prefer the light had an optional attachable reflector or a built-in one?
(a) Optional

8. What would be your primary choice of subject when using the light? (eg portraits, still life, etc)
Event photography, portrait

9. Would you want it to be daylight balanced so it can be mixed with sunlight, or does that not matter to you?
(a) Daylight

10. Please list any photography or videography information services you use (ie magazines, websites, etc)
-just youtube & google search + collegues

11. What finish would you like the product to have?
(c) No preference

12. Would a carry handle on the light be useful to you?
(a) Yes

13. Do you have a preference for the type of bulb used? (say multiple if necessary)
(e) LED

14. What would be your preferred material for most of the light to be made of? (say multiple if necessary)
(a) Metal
(b) Plastic

In order for me to consider anything like this.
It must be portable & battery powered.

 

Thanks for another reply, Jasio. It looks like LEDs are pulling ahead slightly, which is good because I like them. I'll probably use LED "bulbs" because in the unlikely event that they break, people can fairly easily buy new ones. I know fixing a broken LED array isn't too difficult for a lot of modders, but they're not my primary target market.

Another thing that I'm quite liking that's coming through in the survey are the requests for it to be portable and battery powered. It'll challenge me a bit to find powerful, easily replaceable batteries, but I like a challenge. It does mean that my previous plan of LED "bulbs" is kind of thrown off, because they need high voltages. Maybe I should make a custom array.

I can see why they would. I wasn't expecting many photographers to use constant lighting, but my original target market of videographers isn't as large, and the small numbers of photographers who do still use constant lighting gave me enough reason to extend my target market to photographers.

I hadn't, but some of the Litepanels products are quite similar. They look like they're what the survey is steering me towards. Thanks for the link.

That's the spirit! Thanks for the reply.

That's looking like a common sentiment, especially among videographers. I'll be looking into it. I like the idea of being able to use batteries or mains.

 

1. How old are you?
(c) 25-29

2. What is your primary occupation?
Project Manager for a printing company

3. Are you a photographer or videographer?
(a) Photographer

4. Have you used continuous lighting in the past?
(a) Yes

If yes: 4.1. Did you use any light modifiers (reflectors, softboxes, gels, etc) with it?
(b) No

5. Are you currently in the market for continuous lighting?
(b) No

7. Would you prefer the light had an optional attachable reflector or a built-in one?
(b) Built-in

8. What would be your primary choice of subject when using the light? (eg portraits, still life, etc)
Portraits

9. Would you want it to be daylight balanced so it can be mixed with sunlight, or does that not matter to you?
(a) I would like it daylight balanced

10. Please list any photography or videography information services you use (ie magazines, websites, etc)
_____________________

11. What finish would you like the product to have?
(c) No preference

12. Would a carry handle on the light be useful to you?
(a) Yes

13. Do you have a preference for the type of bulb used? (say multiple if necessary)
(f) No preference, but flicker free

14. What would be your preferred material for most of the light to be made of? (say multiple if necessary)
(a) Metal

Good Luck. This is not an easy product to produce, the light needs to be flicker free to offer best useages. Also neutral in color.

 

Thanks! It looks like I'll be using LEDs, and I have some sources that have high power LEDs that are neutral in colour. I'm thinking of one of the 5000K or 5700K Philips Luxeons from this lot. One of the variable ones is also an option if I can make it easy to control the colour temperature.

Do the italics at the bottom of the first table mean they'll run at 350mA or does it mean they need 700mA? I'm not sure of the meaning of how they worded it.

 

Those Manfrotto "lite panels" (and similar Chinese no-names) are extremely weak. And in the case of the Manfrotto at 100 GBP (ouch!) about ~5-7x the cost of a no-name brand. I've used two different types: One that mounts onto your ISO standard hot shoe and it was extremely weak- maybe for macro use? The other was a stand-alone unit that came with a little stand and it was okay for sit-down interviews at a coffee table where you could hide the light but have fairly short throw distances to deal with.

I would definitely lean towards LED "bulbs" which use a standard socket, can always be picked up in an emergency case at the local hardware store, but output significantly more light than the small LED arrays from what I have experienced.

 

They are fiddling the figures slightly. LEDs are more efficient, light output vs power input, at lower currents but out put more light (to a point) at higher current. They're claiming a nominal 110 lumens per watt of electricity but that would only be at ~1.25w (~3.5v * .35a) they're rated at about 2.5w (~3.5v*.75a) but you won't get 220 lumens because the efficiency will drop as current increases. You'll probably be around 190-200 lumens at that power.

I'd have a look at CREE XM-L emitters they're a little dearer but can be pushed much harder so you can get more light per emitter. You can run them at about 3A with sufficient cooling giving 10w (3.5v *3a) per emitter with a similar efficient of 90-110 lumens per watt thus reducing the footprint of the emitting end of the light. You'll still need to think about heat sinking.

 

By litepanels, I was referring to the brand - they make stuff like this. More power output than the cheap chinese ones of the Manfrotto one, but that particular 1'x1' one is over £1000. They're very specialised, and I can't imagine they get millions of sales at that price. Then again, at that price they don't need to.

I was originally thinking of LED bulbs, but most would need 230V AC (pretty difficult with a battery ) and those that don't put out far less light. I'm still looking around - there might be some high power, low voltage alternatives that I haven't seen yet, but at this rate it looks like if I want to go at least partly battery powered I'll need to use normal high-power LEDs.

Thanks for the info on the specs. Does that mean it'd be best to have the current somewhere in between, like 0.55A for maximum efficiency? Each LED would be less powerful but I could have more with the same power source.

Thanks for the Cree recommendation. I definitely won't be able to have them at full power if they're battery powered, but do you think it'd work to have some kind of dual-power system? Ie if I plug in a mains lead the batteries will be disconnected and the LEDs will run at a higher power? I'm just throwing ideas out here - my design is pretty dynamic at the moment and completely influenced by the survey.

Edit:
I think I'll stick with the Philips Luxeon LXML-PW21 LEDs - the power to price ratio is only slightly smaller, and I can't find any of the Crees except in bulk (which I can't really afford). However, the Luxeons seem perfect with a certain setup:

6 parallel sets of "2 LEDs in series with a 1ohm resistor" (quotation marks added for ease of comprehending). Each LED taking 600mA - probably a little higher than maximum efficiency, but it's what I've chosen - I can always modify my calculations. In total that's 3600mA, which at 6V is 21.6W.

My planned battery pack is 2 parallel sets of "5 AA batteries in series". Using 2000mAh Eneloops that's 20Ah at 6V. The maximum (emergencies only) current for an Eneloop is 5A. 3A is the max "sensible" load. Having the 2 sets of 5 batteries in parallel connected to the LED array would give me 1.8A per set of 5 batteries, within the recommended current limit.

At 6V, 20Ah is 120Wh. The array would draw 21.6W, leaving me with an ideal battery life of 5.5 hours - realistically probably 4 or 4.5 hours. I think that's probably enough. If I can combine that with my earlier dual power idea, it's definitely enough to survive until finding a power outlet.

Speaking of dual power, because I've decided on the Luxeons, they won't be able to accept more current when connected to the mains due to their current limits. That means I can use the same power circuitry as long as I can get 6V into the light. I'm thinking of something similar to a laptop charger, with an external power brick to get the 230V AC down to 6V DC. What I need to work out now is how to disconnect the batteries when connecting the mains power. I suppose a switch to change from batteries to mains would work, but I'd like it to be automatic.

 

1. How old are you?
(a) f

2. What is your primary occupation?
Photographer/Educator

3. Are you a photographer or videographer?
(a) C

4. Have you used continuous lighting in the past?
(a) Yes

If yes: 4.1. Did you use any light modifiers (reflectors, softboxes, gels, etc) with it?
(a) Yes

If yes: 4.1.1 Which light modifers did you use? (say more than one if necessary)
(a) Softbox/other light softening (b) Reflector (built into the light or otherwise) (c) Gels or colour filters (d) Flag/other light blocking (e) Other (please specify) _a, b, c, d, e (grids and diffusers____

5. Are you currently in the market for continuous lighting?
(b) No

6. How much would you be willing to pay for a single, 300-500W equivalent light head?
(d) £150-199

7. Would you prefer the light had an optional attachable reflector or a built-in one?
(a) Optional

8. What would be your primary choice of subject when using the light? (eg portraits, still life, etc)
_____Still life_______________

9. Would you want it to be daylight balanced so it can be mixed with sunlight, or does that not matter to you?
(a) I would like it daylight balanced (can't get Tungsten balanced 5x4 film anymore.)

10. Please list any photography or videography information services you use (ie magazines, websites, etc)
___________BJP, Image (AoP)__________

11. What finish would you like the product to have?
(a) Matte ____________

12. Would a carry handle on the light be useful to you?
(a) Yes

13. Do you have a preference for the type of bulb used? (say multiple if necessary)
(d) Compact Fluorescent

14. What would be your preferred material for most of the light to be made of? (say multiple if necessary)
(a) Metal

 

Thanks, Pookeyhead I forgot about grids, but I'd say diffusers go under "other light softening"

 

The thing is you can have all the power in the world but if you can't make it constant or diffuse it then its useless except for one exception a frickin bright fresnel spot light (I.e. A torch).

I have CREE XM-L Lights on my bike yes they are very bright, they get very hot & they light up the entire forest but then they are expensive if you want a decent quality control unit and then you have to deal with the heat & diffusion both issues will need to be addressed & as mentioned only making one unit and on a budget I would say rules out the XMLs.

 

I only said I'd look at them not that they were a perfect solution . To be fair on your bike light you'll likely be running them round about max power, you don't need to, at 1a they're much cooler than the luxeons but still putting out more light in fact the efficiency at 1a is significantly greater than the luxeons at 750ma.

I know next to nothing about designing lighting for photography only making the road and trail bright, I've built XM-L based lights on both my dynamo road bike running at about 3w and on the off road running at 20w both are much brighter than their predecessors based on XR-E lights running at 6w and 15w. They are better because they have a smaller footprint produce more lumens and need fewer optics but they are more expensive per unit and if you need a very wide spread it would probably be preferable to run more emitters further apart at lower power. Horses for courses.

The resistor will work and probably won't be that bad for efficiency as long as you match in put to out put but you can get specifically designed drivers cheap from places like deal extreme which will offer output control and (potentially) higher efficiency but will mean you don't need to faff around with odd battery packs.

If you stick with nickel based batteries then charging is matter of applying a voltage of about 1.5v per cell to the battery and terminating when the voltage reaches a cut off. With that you would just design the circuit to run from the battery and the charging circuit would sit in parallel when it was plugged in the the circuit would run from the mains and any left over power would go to feed the battery.