1. Download our Official Android App: Forums for Android!

Support App turns on Camera Flash for use as Flashlight -- bad idea?

Discussion in 'Android Devices' started by Johnny Cakes, Jan 24, 2010.

  1. Johnny Cakes

    Johnny Cakes Android Enthusiast
    Thread Starter
    Rank:
    None
    Points:
    53
    Posts:
    348
    Joined:
    Oct 13, 2009

    Oct 13, 2009
    348
    68
    53
    There is an app in the market which is written just for the Moment that uses the camera flash as a flashlight -- essentially it turns on the camera flash. The app says not to use the flash "too long" or damage may occur, but the "too long" time period is not defined.

    First, will having the flash on for an period of time damage it?

    Second, if so, any idea what maximum period of time would be "safe?"
     

    Advertisement

  2. Radical-J

    Radical-J Well-Known Member
    Rank:
    None
    Points:
    36
    Posts:
    114
    Joined:
    Nov 15, 2009

    Nov 15, 2009
    114
    7
    36
    I use it but only for 2-3 seconds. I don't want to be the guy that says yeah, don't use it beyond x seconds.

    Or you could think about how many times it would be used if you were continuously taking pics using the flash...
     
  3. AlkiDweller

    AlkiDweller Android Enthusiast
    Rank:
    None
    Points:
    53
    Posts:
    498
    Joined:
    Dec 3, 2009

    Dec 3, 2009
    498
    96
    53
    Seattle
    The original thread about this app is called Flashlight App for Moment and it's currently at the top of the fourth page. There's a lot of posts and I don't think anyone has had a problem so far.
     
  4. Tyrahn

    Tyrahn Member
    Rank:
    None
    Points:
    16
    Posts:
    55
    Joined:
    Nov 27, 2009

    Nov 27, 2009
    55
    1
    16
    Theatre Technical Director
    Milwaukee, WI
    The primary concern would be heat. The Moment does not have a very large LED, but it is packed in pretty close to a plastic lens. If you have it on for a decent length of time touch the flash every so often to make sure it's not getting very hot - if it's uncomfortable to touch it's been on too long.

    I would guess you could leave the LED on for a minute or two, but I'm just guessing there.

    Clark
     
  5. IOWA

    IOWA Mr. Logic Pants
    Rank:
    None
    Points:
    433
    Posts:
    8,853
    Joined:
    Dec 2, 2009

    Dec 2, 2009
    8,853
    2,370
    433
    Network Admin
    Chicago
    Im assuming it would have to be a somewhat long time, as the camcorder uses the flash continuously....
     
  6. CriticalCritic

    CriticalCritic Android Expert
    Rank:
    None
    Points:
    213
    Posts:
    1,872
    Joined:
    Nov 9, 2009

    Nov 9, 2009
    1,872
    556
    213
    Cary, NC
    My biggest concern is battery drain, and my Moment agrees with me. Last night I had just hit the yellow warning on my battery meter, and then I needed to use the flashlight app to clean out some stuff from a car that had been loaned to me. I had the light on for maybe a minute, then turned it off for about a minute, then ran it again for less than one more minute (both uses were with the light on 'high' brightness mode). After those two uses my battery meter was on critical (the battery with the red slash through it) and was about to crap out!

    Then I restarted my phone, and of course the battery meter jumped right back up into the yellow and lasted for at least another 90minutes longer (when I finally got around to plugging it in).

    So, because the battery jumped from yellow straight to critical (completely skipping red) it's apparent that the phone rapidly changed its battery remaining estimates to reflect the huge increase in consumption. Now my question is... can you hurt a battery by draining it too quickly?
     
  7. Tyrahn

    Tyrahn Member
    Rank:
    None
    Points:
    16
    Posts:
    55
    Joined:
    Nov 27, 2009

    Nov 27, 2009
    55
    1
    16
    Theatre Technical Director
    Milwaukee, WI
    Again, the concern is heat. Simply discharging a battery, however quickly, will not harm it in anyway (well, technically, over-discharging a battery can permanently damage it, but the "fuel gauge" in nearly all modern Li-ions prevent that). As you discharge any battery the chemical reacting creating power as well as resistance in internal conductors cause the battery to heat up - the faster the discharge the faster the the battery gets hot. Like with the LED, if the back panel of the phone ever gets too hot to comfortably hold, stop what you are doing.

    The Moment does have the ability to detect the battery's temperature (and you can monitor it with Spare Parts), so it may actually have some kind of self-protection mode that will either shut down the phone or certain services if the battery gets too hot. This is pure conjecture on my part though.

    As far as I know the Moment does not directly take currant drain rate into consideration when determining battery level (like some laptops do), the battery state is purely a reflection of current battery voltage. What you saw would have been created by a sudden voltage drop in the battery caused by a high load. Restarting the phone simply gave the battery time to recover, which it would have done nearly as well with the phone turned on. Depending on what battery code you are using (stock CJ05 or Cl14 kernels vs zefie's kernel) you may have actually been able to leave the phone on and see the battery meter go up back to yellow.

    I generally keep on the low intensity setting, it's normally bright enough for my needs and easier on the battery. If I need a brighter light for longer, I get a real flashlight :)

    Clark
     
  8. Thefoodman52

    Thefoodman52 Android Expert
    Rank:
    None
    Points:
    163
    Posts:
    2,314
    Joined:
    Dec 1, 2009

    Dec 1, 2009
    2,314
    329
    163
    Resource Consumer
    San Diego
    I've left it on high-intensity and propped my phone up against my bed so I could see under my computer desk and re-wire everything to get rid of my rats nest. It was on for about 20 minutes... not one problem to date. I don't feel it's a big concern, as long as you don't use it as the lighting for your house or something.
     
  9. gentlefury

    gentlefury Android Enthusiast
    Rank:
    None
    Points:
    36
    Posts:
    252
    Joined:
    Dec 24, 2009

    Dec 24, 2009
    252
    1
    36
    it's an led....they barely use any electricity and produce little to no heat. There is no logical reason that using it as a flashlight could in any way damage your device.

    Ever seen the led keychain lights? They are extremely bright and they run off a watch battery for months.
     
  10. jvrobert

    jvrobert Member
    Rank:
    None
    Points:
    23
    Posts:
    51
    Joined:
    Dec 29, 2009

    Dec 29, 2009
    51
    31
    23
    Hi,

    I'm the author of the momentflash app, but I'm by no means an expert on the hardware or possible repercussions of using the flash too much.

    A few people in the reviews mentioned they did something to their flash, but then again some of the people who write reviews can barely read (e.g. "Durr, this didn't work on my Droid!"), it seems, so who knows if it's true ;) I tend to doubt it.

    The warning is mostly so people don't come bitch at me if they do happen to damage the LED. My guess is under normal use you'll absolutely be fine especially with "normal" mode (after all, this is what the video camera mode does - turn on the flash and leave it on), but it wasn't designed for "super bright" mode to be used all that much so I'd be careful on bright mode.
     
  11. Tyrahn

    Tyrahn Member
    Rank:
    None
    Points:
    16
    Posts:
    55
    Joined:
    Nov 27, 2009

    Nov 27, 2009
    55
    1
    16
    Theatre Technical Director
    Milwaukee, WI
    Not to sound like as asshole or anything, but both of those statements are completely false.

    In small, extremely low power LEDs (such as those used as indicator lights), power consumption and heat are negligible - but so is illumination. When you start talking about LEDs that create enough light to see by, both power consumption and heat begin to become much more noticeable. Your phone's screen is the single largest power-draw and becomes warm to the touch after it's been on for a while primarily because of screen's LEDs. In high-power applications LEDs are just now being developed that are more power efficient than florescent lights, most common LEDs draw about twice as much power as a florescent light of equal brightness.

    I have a flashlight that uses an advanced Cree white LED, it draws 5W of power to create 100 Lumens of light, and it gets very hot after extended use.

    Clark
     
  12. edp

    edp Android Enthusiast
    Rank:
    None
    Points:
    43
    Posts:
    274
    Joined:
    Nov 20, 2009

    Nov 20, 2009
    274
    28
    43

    Thanks so much for the app! It works.
     
  13. latinmaxima

    latinmaxima Android Expert
    Rank:
    None
    Points:
    113
    Posts:
    835
    Joined:
    Oct 15, 2009

    Oct 15, 2009
    835
    111
    113
    Customer Service/ Quality Assurance Supervisor
    Richmond ,KY
    I use the regular and bright mode often and other than the battery draining more quickly then regular mode it doesn't seem to get hot nor fail at all. If I plan on using it for a long time I hit end to turn off the screen. Otherwise the screen is on I have no issues.


    On another note: Can we get a mod to merge this with the original thread. I think these are good concerns but should continu to remain with that thread.
     
  14. IOWA

    IOWA Mr. Logic Pants
    Rank:
    None
    Points:
    433
    Posts:
    8,853
    Joined:
    Dec 2, 2009

    Dec 2, 2009
    8,853
    2,370
    433
    Network Admin
    Chicago
    Check your private messages.

    Also, GREAT APP!
     
  15. ovrrdrive

    ovrrdrive Android Expert
    Rank:
    None
    Points:
    163
    Posts:
    1,215
    Joined:
    Dec 18, 2009

    Dec 18, 2009
    1,215
    389
    163
    My last two Samsung phones had this feature built into them and it stayed on about 8-10 seconds when you activated it. I used it all the time and never had any problems. While I do think the led will generate some heat I don't see it being so much that a phone designed for outdoor use will be affected by it. As for power consumption, why the hell do you think they use led's in the first place?

    I didn't know an app was out yet that enabled this. I'm going downloading. :)
     
  16. Cirga

    Cirga Member
    Rank:
    None
    Points:
    15
    Posts:
    49
    Joined:
    Nov 5, 2009

    Nov 5, 2009
    49
    0
    15
    I use the LED MomentFlash app constantly at work. Its better than my real flashlight (which is not LED). I have used it for up to an hour on the first click setting. I noticed before that when I left it on the second intensity it would actually show my battery was dead within a few minutes.. but i would reset my phone and it would read the battery as full again. It was strange.. so I just used the first click setting.

    I havent had a problem at all other than that. Now that I have the CL14 update.. I will try using the higher intensity more often to see if it still drains.
     
  17. ramiss

    ramiss Well-Known Member
    Rank:
    None
    Points:
    53
    Posts:
    180
    Joined:
    Nov 28, 2009

    Nov 28, 2009
    180
    55
    53
    Can anyone explain why, after a reboot, I have to click the widget twice to get the LED to come on at all? This happened before and after I rooted and wiped the OS.
     
  18. Cirga

    Cirga Member
    Rank:
    None
    Points:
    15
    Posts:
    49
    Joined:
    Nov 5, 2009

    Nov 5, 2009
    49
    0
    15
    It has always worked this way for me using the widget. The first tap does nothing, and the second turns it on. After I turn it on and off once, it no longer needs that first tap. maybe the first time loads it into running programs?
     
  19. jvrobert

    jvrobert Member
    Rank:
    None
    Points:
    23
    Posts:
    51
    Joined:
    Dec 29, 2009

    Dec 29, 2009
    51
    31
    23
    Yeah, I just noticed this too. I'll take a look soon and post a fixed version, it's something minor.
     
  20. jvrobert

    jvrobert Member
    Rank:
    None
    Points:
    23
    Posts:
    51
    Joined:
    Dec 29, 2009

    Dec 29, 2009
    51
    31
    23
    OK, this should be fixed as of version 1.02 of momentflash (on App market now).

    Jason
     
  21. Jax63

    Jax63 Lurker
    Rank:
    None
    Points:
    5
    Posts:
    1
    Joined:
    Aug 22, 2012

    Aug 22, 2012
    1
    0
    5
    I use my flashlight app when I take my dogs out in the morning as it is dark. Our trip outside typically lasts 15 or so minutes and I haven't experienced any particular problems using it that length of time. I hope this helps.:)
     

Samsung Moment

The Samsung Moment was one of the first Android Phones with a slideout keyboard.

Share This Page

Loading...