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  1. #151
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    Quote Originally Posted by Roger Huston View Post
    Hello,

    Just checked out your new build blog. Cool stuff. BTW, it would be handy if you could post the weights of your products on your website in the list. I think people may think that the unit is much heavier than the 130g you have listed above. I know I did.

    As for helmet lights, I would think your main competition in the States would be with the new Dinotte XML-3 as this light is a little smaller and at the same price point as the DS-1300 (Sub $300), and close in output. The review just posted on it yesterday or today. It looks much smaller than the DS-1300 unit, but since the weight is 102g, so maybe not. For me, I will probably get the DS-1300 and DS-500 combo and once I try them out, will decide what I want on my head. I have an old HID light that works fine for now for that and I can put the battery in my back pocket.

    As soon as you get closer to shipping, let me know so I can place my order.

    - Roger
    The XML-3 is definitely another smart light...very similar to the DS-1300 in performance.
    The next DS-1300 will likely end up being sub 120 gram for the light body and clamp mount. The extension bar, which you would probably want to use for bar-mounting adds a few grams, but while mounting on the bar, it probably doesn't matter.

    Here's just some of my random observations from comparing the two the backyard shots (attached side by side here just for fun, DS on left, XML3 on right)
    Only two really noticeable differences stick out to me.

    DS - slightly more neutral (warm) color index
    XML3 - tends toward the cool side (nothing really wrong with that, just different)

    DS - slightly tighter spot projection and nearly identical near-field width
    XML3 - because of the faceted lens, it produces a very wide slightly more diffuse pattern.

    You can definitely see more "UP" light toward the top of the tree with the XML3.
    With the DS being a little tighter, there might be a slight advantage for road use.

    From the trail shots, the main difference is the color temperature. Browns will be more brown with the warmer light. And if you use your imagination, you might think that you have more discrimination of detail among the leaves with the warmer light, but this is an extremely subjective thing.

    I'm not sure I could make a decision just on the beamshots. What we're seeing with the mix of backyard and trail beamshots is that the content of the shot (color of background, terrain, depth, nearfield objects, etc.) can have a real impact on how the reflected light is viewed by the camera. In the backyard shots the DS looks "brighter" (I really don't like to use that word), while on the trail the XML3 looks "brighter." It really is very hard to judge between two very similar lights without having them both in your hand for real world comparison, and even then you can drive yourself crazy looking critically at aspects of the light that really may not matter when you're actually riding. When I'm out testing a new light, I really do have to tell myself to "stop looking at the light" and just ride. When you finally get to this point, and like Francois says, the light becomes "transparent" then you know you've got a good usable light, and there are plenty in the shootout that can do it.

    It's such a hard decision in some cases for a semi-major investment, which is why I consider all my lights to just be a "demo" until you really decide you want to keep it.

    OH, and just as an aside, you can run the DS-500 with any of the Dinotte batteries. I just need to provide a short "adapter" cable.

    DS-1300 on left, Dinotte XML3 on right.
    Attached Thumbnails Attached Thumbnails DesignShine... WOW!-ds_xml3_side_by_side.jpg  

    DesignShine... WOW!-ds_xml3_side_by_side_trail.jpg  


  2. #152
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    Quote Originally Posted by pethelman View Post
    Thanks VERY much for the tip on the HEW. I've looked at some of the beam shots, and it's hard to make a definitive call. I'll definitely drop back to the R3 or below if I don't like the throw that it generates.

    I think you'll like the Cateye mount a lot. Very minimal weight and low profile. I especially like that you can torque down on the bolt that it rotates about and change the friction level. This way you can get even finer aiming ability, if you find yourself needing to aim between two of the detents. That would be my only gripe that the spacing between each detent could be a little finer.
    no worries. I remember Quazzle hyping the HEWs up amid much skepticism on the DIY forum and no favourable feedback from users after they were released. I think it's also a consequence of the lack of HEW specific optics (something about weird emission angles and phosphor on the HEW dies), but I'm not going to grind my 20mm triple optics axe

    tried the mount out last night and was very impressed. Even with the spacer on the wrong way round on all my lights (doh!) I still managed to get a good angle with it right at the front of my helmet (still snagged it though). Unfortunately the beam got completely washed out by my bar light (2 XM-L at even 2A will do that to 1 XM-L at 1.5A) but I think I'll keep my commuter light on there permanently. Also, out of curiosity I weighed my commuter light:
    - light head 68g
    - helmet mount 24g (23.561g to be precise )
    - 2S battery 148g

    I was surprised that the battery weighed that much, guess the Digikey 18650 holder didn't help. Either way, felt very balanced and didn't notice the weight last night or this morning on the ride into work

  3. #153
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    Stephen,

    Thank you for the pictures, I did check them out. I will definitely get your light package for the bars and back and once I have it in hand, check it out for use on the helmet. I believe strongly in matching lights as best I can, both in strength and color if possible. For the better part of a decade I rode with Nightrider HID lights on both head and bars and I know the importance of keeping light sources of equal strength so your eyes don't have to adjust to varying light levels.

    For me, I am a bit sensitive to the weight on my head and the lighter the better. Until I get to see the thing in my hand and try it out, I am just guessing. But, what I do like about you, more than any other manufacturer is that you stand behind your lights and are willing to help us make it right. I like your "demo" philosophy. I will order, just wish the new lights were ready now and I really hope they are ready before Christmas instead of after.

    - Roger

  4. #154
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    Roger, according to the latest on the Designshine build blog, he said its looking like it's going to be "a new design for a new year..."

  5. #155
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    Quote Originally Posted by GraXXoR View Post
    Roger, according to the latest on the Designshine build blog, he said its looking like it's going to be "a new design for a new year..."
    Yes, I'm pretty bummed about it myself. But I think the time that I take now in finding a good CNC partner will ultimate be well spent, as I'm getting bids from several shops and even looking at a custom extrusion option for the lids. I'm hoping that I can do enough quantity to at least get down to the price-per-unit machining cost of my local guy who's a one man show and semi-retired and owns his own shop (i.e. no overhead). His work is second to none, but to get into increased volume for him might be tough.

  6. #156
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    New Headlight Beam Shots

    OK, just finished up a test rig to try out one potential new XP-E variation. I also put together the "throw monster" (double triple XP-E) just for fun. Let me know what you think about the slightly cooler color temp.

    The orange cones are +30, +60, +90, +120, and soccer ball at +150 ft
    Fence in the far background at 300 ft.

    Shot setup: Same settings as for the shootout this year.
    4 sec exposure
    100 ISO
    4.0 Aperture
    Manual focus
    Daylight white balance

    I used two different lenses to try to give a better perspective on "throw" vs. "width."

    The first three shots all use the telephoto lens in this order:
    1) Original DS-1300 XP-E (single triple) minimum 5000K color temp
    2) New XP-E (single triple) probably in the minimum 6000K color temp range
    3) New XP-E (double triple), aka "throw monster"

    The last two shots show the importance of having a second lens of the frosted variety by using the wide angle lens and showing everything back to a few feet in front of the wheel.

    4) New XP-E (double triple). Notice the lack of spill light in the near field (it's why they work so good for throw).
    5) Add in the XP-G (R5) with a narrow frosted lens coupled with the New XP-E and you get "almost" as good on throw, but far better wide angle coverage and a nice smooth beam all the way out. For my eyes it's almost the perfect beam pattern.

    I'll post the full res shots over on the DesignShine Blog.
    Attached Thumbnails Attached Thumbnails DesignShine... WOW!-ds_1300_original_xpe_spot.jpg  

    DesignShine... WOW!-ds_1300_new_xpe_spot.jpg  

    DesignShine... WOW!-ds_1300_new_dual_xpe_spot.jpg  

    DesignShine... WOW!-ds_1300_new_dual_xpe_spot_wide_angle.jpg  

    DesignShine... WOW!-ds_1300_new_xpe_spot_xpg_frosted_narrow_wide_angle.jpg  


  7. #157
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    Stephen,

    I noticed you said that on a helmet, if you limited the light to 3 or 4 you could run it on a magicshine 2S pack? Does that mean I could run it sufficiently well on a 2S2P magicshine pack? You said it 'wasn't recommended' in a post somewhere earlier... Could you elaborate? Would it
    A) damage the battery
    B) damage the light/controller
    C) reduce the brightness
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  8. #158
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    Quote Originally Posted by GraXXoR View Post
    Stephen,
    You said it 'wasn't recommended' in a post somewhere earlier... Could you elaborate? Would it
    A) damage the battery
    B) damage the light/controller
    C) reduce the brightness
    You could spend a little time and read this thread, including link to Design Shine website to answer your own questions.





    It's because it's so bright at night that he recommends only level 3 for both tail light and head light unless you ride where there's no cars and less population.

    Level 4 and 5 use during the day.
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  9. #159
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    Quote Originally Posted by GraXXoR View Post
    Stephen,

    I noticed you said that on a helmet, if you limited the light to 3 or 4 you could run it on a magicshine 2S pack? Does that mean I could run it sufficiently well on a 2S2P magicshine pack? You said it 'wasn't recommended' in a post somewhere earlier... Could you elaborate? Would it
    A) damage the battery
    B) damage the light/controller
    C) reduce the brightness
    Sure, let me clarify on those points.

    A)
    No problem for the battery. At 14 watts (level 5) and 7.4V, the current will be fairly high out of the battery (1.9 amps), but this shouldn't be a problem for the typical 18650-based li-ion pack. The only time you really have to worry about damaging a battery is if you over discharge or alternately overload and pull too much current (sustained). The over-discharge scenario is taken care of by the light controller, since it is programmed to shut off well before the battery reaches dangerous discharge levels.

    C)
    Since the light controller is a fully regulated boost mode current controller, it will necessarily maintain a constant current to the LEDs for a particular power level, regardless of the input voltage, so the lower voltage will not affect brightness in any way.

    B)
    This is the only area of concern for using 7.4V as the source for the headlight. To drive all six LED in series (lots of reasons for using the series configuration that I won't go into), you need upwards of 18 to 19 volts. As a rule of thumb, the larger the gap between the input source and the output drive level, the more inefficient the controller and the more power is dissipated in the components of the controller since it is now having to "work harder" to boost the voltage up to the necessary level. This is my sole concern for running the light for extended amounts of time at the highest drive level with the 7.4V input. The taillight, being lower power, does not have the same concern. I do plan on getting the 2-cell pack and doing some thermal testing with the headlight, just to definitely characterize the limits.

    Hope that helps.

  10. #160
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    Stephen,

    That is the info I was looking for.

    It would be nice to know some run times/efficiencies for driving your light at various levels with a 7.4v pack.

    I know how busy u must be, but it might be nice data to add to your runtimes chart.

    Thanks as always for the rapid response!



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    No need for the lippy attitude.
    I've "read the posts", been to both his old and new websites and still had that question.
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  11. #161
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    Quote Originally Posted by GraXXoR View Post
    Stephen,

    That is the info I was looking for.

    It would be nice to know some run times/efficiencies for driving your light at various levels with a 7.4v pack.

    I know how busy u must be, but it might be nice data to add to your runtimes chart.

    Thanks as always for the rapid response!
    You bet. That's a really good suggestion. Based on my experience with instrumented run-down testing on the 11.1V packs. I went back and made some estimates for the 7.4V pack. In practice, I've measured efficiencies in the controller that were on average 4 to 6% lower with the 7.4V input. Based on empirical data, I've found that I can "de-rate" the calculations to account for the fact that input current from the battery does not increase linearly over the full discharge cycle, so the estimates should be pretty good. I'm sure there's a margin of error, probably in the +/- 10% range, but that's really just a guess.

    Bottom line is that for the penalty of carrying around one extra 18650 cell, you can get essentially the same run times out of a 4400mAH 7.4V pack as you can a 2800mAH 11.1V pack. The only other caveat being that I would not recommend the full 700mA drive on the headlight with the 7.4V pack. If you just really wanted to use the 7.4V with the headlight, then the best option would be to reduce the maximum drive down to 500mA (via MaxFlex programming). After doing this, the maximum output of the light will be reduced down to the 900 to 1000 lumen range, but then you'd have slightly higher output compared to just limiting yourself to level 4 with the 700mA drive.

    I've updated the run time tables on the website.
    Also updated to reflect the measurements made with the newer version 6 Maxflex, but subject to change as I make more measurements to get a good average.

    Do note that I've observed some issues with the GeoMan 4.5AHr battery when running in high power flash mode, and I can elaborate on those if need be.

  12. #162
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    Stephen,

    Wow... This is the difference when dealing with an individual/small company! Response speed!
    Can't believe you've already updated your website with a full set of graphs... smashing!

    That's just what I was looking for. I have four of these packs, so it's nice to know that I can reuse them in emergencies....

    I notice, you said that the voltages involved with the rear light are less than those with the front light, but I see on your data that the "penalties" for running a 2S pack are the same as for the front light, i.e. 3S1P ≈ 2S2P.

    Still, it's really nice to see that the run times with s 2S2P are entirely practical and run for longer than the Magicshine 816 (1.8h at - rarely used- full power) which is what I'm currently running with.

    On a different note, how difficult is the reprogramming, say, were I to swap between an 3S and a 2S pack in order to set protection switch off voltage?

    I know that the maxflex has some user programmable aspects, but accessing all the function menus though a one button interface sounds about as much fun as punching out programme cards with my bare fingers :-)

    Also, could you explain to us a little more about the cell balancing aspect of the new build? That sounds like a really high-end feature that no $300 dollar light currently boasts. That would really put your new build "in the spotlight" so to speak...

    As always, keep us posted. I'm really enjoying hearing your progress.

    Craig.

  13. #163
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    Quote Originally Posted by GraXXoR View Post
    Stephen,

    Wow... This is the difference when dealing with an individual/small company! Response speed!
    Can't believe you've already updated your website with a full set of graphs... smashing!

    That's just what I was looking for. I have four of these packs, so it's nice to know that I can reuse them in emergencies....

    I notice, you said that the voltages involved with the rear light are less than those with the front light, but I see on your data that the "penalties" for running a 2S pack are the same as for the front light, i.e. 3S1P ≈ 2S2P.

    Still, it's really nice to see that the run times with s 2S2P are entirely practical and run for longer than the Magicshine 816 (1.8h at - rarely used- full power) which is what I'm currently running with.

    On a different note, how difficult is the reprogramming, say, were I to swap between an 3S and a 2S pack in order to set protection switch off voltage?

    I know that the maxflex has some user programmable aspects, but accessing all the function menus though a one button interface sounds about as much fun as punching out programme cards with my bare fingers :-)

    Also, could you explain to us a little more about the cell balancing aspect of the new build? That sounds like a really high-end feature that no $300 dollar light currently boasts. That would really put your new build "in the spotlight" so to speak...

    As always, keep us posted. I'm really enjoying hearing your progress.

    Craig.
    Thanks Craig.
    Let me see if I can clarify on few of those points.
    First off on the 11.1V vs. 7.4V issue. Yes, there is a small decrease in controller efficiency as the input voltage drops. This, in and of itself however, is not a large contributor to the total power consumption, but since it's all manifested in the controller board itself, then from the controller board's perspective, it can make a big difference. From the studies that have been done on the Maxflex, the general rule of thumb is to avoid exceeding 2 watts in the controller unless you can provide a method of heat-sinking for the power inductor. In a package like this, it's virtually impossible to do that, so the only recourse is to just hold the power down.

    The "penalty" aspect of dropping the input voltage comes from the fact that this is a constant power device. As you drop the input voltage, more and more current is required to maintain the same power level. And as current goes up, so must the battery capacity to maintain the same run time. It just so happens to work out that the 2800mAH 11.1V and 4400mAH 7.4V are nearly equal with regard to power capacity. In fact, just look at these numbers. They could be considered to be "power" capacity. We're just not used to seeing a battery described this way.

    2.8*11.1 = 31.08 Amp-Hour-Volts
    4.4*7.4 = 32.56 Amp-Hour-Volts

    Now we need to penalize the 7.4V pack by about 5% (the difference in the controller efficiency) and we have:

    32.56 * 0.95 = 30.93

    Which is practically identical to the 11.1V pack.

    Concerning programming... I must say, when I first starting working with the Maxflex, it was a bit daunting to get my head around all the options. However, once you distill it down to just the few functions that are required for this particular application, it really is pretty easy. I plan on making some tutorial videos just to help folks get past the learning curve, so they can quickly be able to perform the operation exactly as you describe. Say for example you find that your 11.1V pack is dead and you want to use your 7.4V pack. If you don't re-program the cutoff limits, then as soon as you try to use the 7.4V, the light will think it's dealing with a seriously depleted battery and go into shutdown.

    So, you'd then break out your cheat sheet with just a few lines of instructions telling you which menu to select. You'd then enter the new cutoff voltage by tapping out the number for each digit XY.Z. So for a 6V cutoff, for example, you'd be entering 06.0 in a process like this:

    no-click = 0, followed by a PRESS to enter,
    6 clicks, followed by a PRESS to enter,
    no-click = 0, followed by a PRESS to enter.

    In this case, a video is worth a thousand words. If it was something you did often, then you'd easily be able to change between each voltage standard in a matter of minutes.

    Now, on the flip side, if you were programmed for 7.4V operation and needed to use a known good 11.1V pack for a while, you could do it straight away without the need to reprogram.

    Concerning balancing... I know that some packs say that they perform this function, but I'd certainly not assume that all packs do. If you look at any of the lithium polymer packs typically used in RC-airplane applications, they are literally bare cells. They have no hard metal case, and they have no on-board circuit protection (except for the speed controller), so when you charge a battery like this, you really NEED to use a balancing charger. This means that each cell will be monitored during the charging process and the charger's "brain" will compare each and make adjustments (discharging some if necessary) to insure that each cell is at the same voltage. This prevents any individual cell from becoming over charged or over discharged over time, which is not only a safety factor, but will also prolong the life of the pack. All of the 11.1V packs that I've spec'ed out, have to pass a quality test before they get to me. And I run each one through a full charge and load test before letting them go.

    As an aside...
    I posted a few more user-pics over on the new web site today if you're interested.

    Thanks for all the great questions!

  14. #164
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    Quote Originally Posted by GraXXoR View Post
    CDA:

    No need for the lippy attitude.
    I've "read the posts", been to both his old and new websites and still had that question.
    No need for getting your panties all twisted .

    That was a genuine response/post. Lighten up Francis; this is the internet...
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    Stephen,

    Now THAT'S what I call a comprehensive answer! Yes, with driver inefficiencies taken into account I can see that the Watt Hour ratings come out even, I guess due to the higher quality 2800mAh(?) cells used in your packs.
    It's good to know that reprogramming is only a few minute rather than half an hour job.


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  16. #166
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    Quote Originally Posted by GraXXoR View Post
    Stephen,

    Now THAT'S what I call a comprehensive answer! Yes, with driver inefficiencies taken into account I can see that the Watt Hour ratings come out even, I guess due to the higher quality 2800mAh(?) cells used in your packs.
    It's good to know that reprogramming is only a few minute rather than half an hour job.
    Yes, I spec'ed out the higher capacity 2800mAH batteries for my triangular 11.1V packs. They're pretty unique. A lot of energy in that small package and easy to strap to about anything. To my knowledge L&M is the only other outfit that has a similar battery, but it's crazy expensive. My new packs are using the new 2900mAH cells, but I'm not going to get too excited until I can do some full run-down tests and compare. They're supposed to be shipped to me this Monday, so we'll see soon.

    So did you escape anything serious from the Tsunami? I sure hope so!

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    Excellent news! High qual batteries with balancing are sure to be a winning combo.

    Just out of interest, why did you say that you should limit the current to 500mA rather than the already conservative 700mA at which you drive your LEDs?
    So say 14W output with, let's say a 20% inefficiency case. That would be about 17W input. At, even 6V that would be less than 3A, which with 2.2Ah cells is less than 1.4C current discharge. That doesn't seem particularly outrageous. Does the Magicshine battery pack limit output current?

    I have lived in Japan for the better part of 13 years now and as such have experienced numerous earthquakes of magnitude 5 and a couple of magnitude 6 or so. But the massive magnitude 9 earthquake that struck in spring was thousands of times more powerful than those and was actually more than 200 times more powerful than the infamous Kobe Earthquake of '95 which killed thousands.

    My school, which I was in with my students at the time of the quake, shook violently from side to side like a boat on stormy water. There was a lateral movement which peaked at about 8 yards, backwards and forwards once a second or so, for over 5 minutes. It was impossible to remain standing and for a minute there, we honestly thought we were all going to die.

    It was perhaps one of the most terrifying moments of my life and since that time, every slight tremor sets my heart off.

    But, on the other hand, the earthquake has brought our community together for the first
    time literally since the war and I have made more friends since March than I made since coming to Japan until that point.

    Moreover, because of the Earthquake, I have started riding around Tokyo, 20km or more per day, in order to visit all of the wonderful places my city has to offer because, if one believes the news, a massive, Tokyo earthquake is on its way...

    And I guess, indirectly I have the earthquake to thank for my interest in bike lights, since 90% of my riding is done after 9pm...

    Sorry for the long post.

    Craig.
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  18. #168
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    Quote Originally Posted by GraXXoR View Post
    My school, which I was in with my students at the time of the quake, shook violently from side to side like a boat on stormy water. There was a lateral movement which peaked at about 8 yards, backwards and forwards once a second or so, for over 5 minutes. It was impossible to remain standing and for a minute there, we honestly thought we were all going to die.
    8 metres! Back and forth! Once a second! For 5 minutes! That I think Craig is the most telling description of a major earthquake I have ever read! For those metrically deprived I'll remind you that 8 metres is about the height of a 2 level block of flats or about 25 feet! I find it very, very hard to imagine such an experience. See Tokyo while it's there...

    Back to bike lights - I use my DS lights for commuting only. I find the original 3 cell batteries very adequate for my 40minute commute. I use the lights day and night (different settings). I've never run out of juice and I only charge them about 1 X week.

    Incidentally I seem to get much more of what I think is referred to as 'respect', especially at T-junctions where previously it was not unusual for waiting drivers to pull out, completely disregarding my approach (or perhaps misjudging my speed). I've also lost count of the shouts 'your lights are on'... But being a long-time dynamo user I'm used to that!

    BTW, I use my DS lights without Stephen's extension bars. I just relocated the Cateye mounts directly to the light bodies. I use them on the bars at the front and at the rear of my pannier rack with no problems at all (using the special DS rack mount at the rear). I find it a neater and more compact set up for my purposes. For those with 'bare' road bikes I think the DS500 might be better served by a seatpost mount that made better use of the Cateye sliding shoe with the light in a horizontal position (as the mount was designed to work). I believe the top part of the handlebar mount (the bit that slides into the 'spacer' attached to the lights) is removable and could be mated to an alloy adapter which in turn could be maybe fitted to a standard Cateye or other) seatpost clamp - maybe a Smart-style clamp like Dinotte seem to use.

    Just an idea...

    Savvas.
    Last edited by savvas; 11-25-2011 at 12:58 PM.

  19. #169
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    Quote Originally Posted by GraXXoR View Post
    Just out of interest, why did you say that you should limit the current to 500mA rather than the already conservative 700mA at which you drive your LEDs?
    So say 14W output with, let's say a 20% inefficiency case. That would be about 17W input. At, even 6V that would be less than 3A, which with 2.2Ah cells is less than 1.4C current discharge. That doesn't seem particularly outrageous. Does the Magicshine battery pack limit output current?
    I agree, I've never heard a description in those terms before. Just amazing! Very cool to hear how the tragic experience is drawing people closer together.

    To answer your question... The total power nominally consumed by the light on high is around 14 to 14.5 watts (don't have my spreadsheets in front of me at the moment). This includes the controller losses. So you are correct, it's not too hard for a 7.4V pack to run either light. Running both (head and tail) off of a single 7.4V might not be the best idea though. The power dissipated in the LEDs themselves at a maximum drive of 700mA is around 12.6 watts (give or take), so the issue is how well does the controller handle it's own power dissipation?

    One of the super-nice things about the TaskLED driver boards is that George really went out of his way to provide a large area on the board for heat sinking. But, one of the tricky balancing acts is getting heat out of the controller while also "sensing" and protecting the LEDs. At the same time that your trying to get heat out of the controller, you're also raising the temperature of the "sink" itself. Its just HOT in there. This is where the design of the housing is really important. In reality, the only area of concern for the 7.4V input is where the controller happens to be running right on the "edge" of needing to throttle back. Since the efficiencies of the controller drop by another 6% or so with the lower voltage input, some of that excess power gets burned in the "flyback" inductor, which is whole reason for concern. Because of thermal gradients in the board itself, it's possible for the inductor to get "hot" very rapidly before the thermal detection has a chance to kick in. The big question is HOW HOT will it get and is it too hot? I have a hard time answering that question empirically right now, so I can only go by the math and the recommendations that George has made, based on his own studies. You can find his white paper here:
    http://www.taskled.com/leds/max4_thermal_guide.pdf

    Or just the summary quoted here:
    "At power levels with driver heat losses in the 2W range, it is sufficient to utilize a single heatsink attached to the gold thermal attachment area. As heat losses increase beyond 2W it may be necessary to provide heatsinking of the inductor to prevent shutdown and possible damage of the switcher IC."

    SO... the reason I recommended running at a 500mA drive was, 1) just to completely avoid the borderline region of operation with the 7.4V input (especially when it's near the end of the charge), and 2) to give slightly higher output than if using the 700mA drive and running on level 4 instead of level 5.

    Long answer I know... and I'm still not sure I explained it adequately, but I hope that helps a bit.

  20. #170
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    Just saw your build blog. The battery packs look excellent. How are you going to waterproof them? And balancing, yay! Should give decent lifespan.

    I have a lens question.

    It's nice that even an elliptical lens could be retrofitted/swapped in to your #2s

    But I remember you mentioned the elliptical lens suffers a lot of loss. Is it a significantly greater loss than the wide frosted?

    Because I'm presuming that the frosted lenses are omnidirectional rather than directional, by which I mean, they scatter light in an even sphere rather than a horizontal plane such as a cylinder.

    Why I'm asking is, I love a good wide flood, but it's really annoying that in doing so, half of the light ends up in the trees. Since I spend practically no time in the bush.

    I would love some sort of lens that spreads light horizontally more than vertically but doesn't have the huge losses of the elliptical lens. Any options available?
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  21. #171
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    Quote Originally Posted by GraXXoR View Post
    Just saw your build blog. The battery packs look excellent. How are you going to waterproof them? And balancing, yay! Should give decent lifespan.

    I have a lens question.

    It's nice that even an elliptical lens could be retrofitted/swapped in to your #2s

    But I remember you mentioned the elliptical lens suffers a lot of loss. Is it a significantly greater loss than the wide frosted?

    Because I'm presuming that the frosted lenses are omnidirectional rather than directional, by which I mean, they scatter light in an even sphere rather than a horizontal plane such as a cylinder.

    Why I'm asking is, I love a good wide flood, but it's really annoying that in doing so, half of the light ends up in the trees. Since I spend practically no time in the bush.

    I would love some sort of lens that spreads light horizontally more than vertically but doesn't have the huge losses of the elliptical lens. Any options available?
    You're assessment is essentially correct, but I may have miscommunicated a bit on the lens efficiencies. The elliptical is actually quite efficient. For comparison, here are some efficiency numbers:
    Spot Lens (XP-E, 88.7%); (XP-G, 87.3%)
    Elliptical Lens (XP-E, 88.1%); (XP-G, 86.5%)
    Narrow Frosted (XP-E, 85%); (XP-G, 85%)

    The elliptical lens makes a nice "flat" and wide beam, far wider than the "round" lenses. Here are the angles for the elliptical:
    43 X 16 FWHM - XPE
    43.6 X 23.3 FWHM - XPG

    Now, the one lens where you really get clobbered on the efficiency is the "wide" frosted lens. To me this lens is just too "lossy" for this application. Here are the numbers:
    Wide Frosted (XP-E, 80%); (XP-G, 78.3)

    The elliptical really does work quite well (you can see some wall shots of the red taillight earlier in this thread that show the general shape). I only have a few misgivings for using it on the headlight:
    1. It's so wide (I'm talking way past the edges of the road), that you do give up some forward intensity.
    2. With a wide flat beam, it's important to mount the light lower to the ground. A helmet mounted elliptical just doesn't work at all. It projects almost a horizontal "line" on the ground.
    3 With the lowered intensity of the wide spread from the XP-G ellipitcal, the combination with the XP-E spot is a little abrupt. In other words, you have this nice spread of light, practically covering your entire field of few, then you have a really intense SPOT in the middle without a nice transition between the two.

    Now, one option that I haven't tried, which might really be the flood-lovers dream, is the elliptical on the XP-G, and the narrow frosted on the XP-E. I'll definitely have to try that one out and post some shots once I get my new stock of XP-G boards.

    Hope that helps!

  22. #172
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    Quote Originally Posted by pethelman View Post
    ....Now, one option that I haven't tried, which might really be the flood-lovers dream, is the elliptical on the XP-G, and the narrow frosted on the XP-E. I'll definitely have to try that one out and post some shots once I get my new stock of XP-G boards.

    Hope that helps!
    This is what I like about your set-up...All the great options!

    At this point I'm beginning to figure that the Aliens have implanted a mind-reading device into my brain and are linking it to the one in yours.

  23. #173
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    It just gets better! Thx for the lovely data! Its a descerning light buyer's dream!

    When Francois (?) did his video he stated that what impressed him enough to review your light was the clear way you explained your lights' functionality and the copious excel spreadsheets to sent him with various data!

    A nice balance might be spot on the XP-G and elliptical on the XP-E that would be somewhat like the MJ-816 which uses a P7 with orange peel reflector and 2 XP-Es with elliptical lenses.

    Or would that just be a compromise of both spot and flood!

    Oh for a range of elliptical lenses...
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  24. #174
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    Good News

    Learned today through my LED supplier that the XP-E that I'll be getting for this current build is really and truly an R4 XP-E, NOT High Effeciency White (HEW). Apparently CREE had a low enough yield of these "super" XP-E that they didn't even make the datasheets. They really are good, and I'm not sure how I was lucky enough to get my hands on them?

    On an unrelated note, I discovered tonight that the little right angle bracket that I ginned up for a recumbent mount concept works really well for the problematic aerobar mount. Pretty cool. I think I'll make a few and throw them in with the anodizing run.
    Attached Thumbnails Attached Thumbnails DesignShine... WOW!-ds_aerobar_mount1.jpg  

    DesignShine... WOW!-ds_aerobar_mount2.jpg  

    DesignShine... WOW!-ds_aerobar_mount3.jpg  

    DesignShine... WOW!-ds_aerobar_mount4.jpg  


  25. #175
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    Would driving two 1300's from a single six cell battery be possible/unadvisable?


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