DL in the field

Discussion in '35mm Cameras' started by Alan Justice, Feb 16, 2011.

  1. Alan Justice

    Bill Graham Guest

    Yes. I probably was. But Nikon doesn't specifically say that one can run
    their cameras off of a car cigar lighter socket, so I was reluctant to do
    this. I could have built a zener diode regulator to protect the cameras
    also, but I was too lazy, and the little power supply seemed lika a good
    solution at only $30......
    Bill Graham, Feb 19, 2011
    1. Advertisements

  2. Alan Justice

    Alan Browne Guest

    That's up to you according to your various needs. Obviously a new
    laptop that you can uses as a main home computer and travel with has its
    appeal as long as you get a decent monitor (an issue in itself) for
    photo editing.

    Or a new desktop with a cheap netbook to meet your travel needs.

    Dial-up is a separate issue - and I can't even imagine using it now with
    the deluge of image rich e-mails I (unfortunately) receive.

    (Would be nice to have an e-mail account that was strictly ASCII text only).

    Don't top post.
    Alan Browne, Feb 19, 2011
    1. Advertisements

  3. Alan Justice

    Alan Browne Guest

    All these extra conversions are wasteful to be sure.

    If one knows the voltage for the laptop, they could make a 12 to 24 V
    input DC|DC converter that outputs the right voltage to the laptop. (A
    technician with nothing to do in his spare time should be able to get
    the parts, assemble and test this in no time).

    Then plug into the car batteries (series or parallel) and get a lot more
    laptop juice. I'd run it at 24V (series) into the converter to reduce
    conversion loss and run the converter cooler.
    Alan Browne, Feb 19, 2011
  4. Alan Justice

    otter Guest

    I picked up an Acer AO 522 with the C50 processor for $330 on a whim.
    Very nice for such a small package, and great graphics. Easily
    handles 1080P HD. I can't get it away from my wife. She uses it to
    video-skype with my daughter, and surf the web.

    Not sure I'd want to try running CS5 on it, but certainly much easier
    to take on trips than a large laptop.
    otter, Feb 19, 2011
  5. Alan Justice

    Alan Browne Guest

    CS5 would probably run on it quite well, if not snappy quick. But
    Elements 7 (or whatever it's up to) would probably be a better choice
    for a road machine. (Yes, Elements reads raw).
    Alan Browne, Feb 19, 2011
  6. Alan Justice

    Savageduck Guest

    I don't know why everybody is trying to complicate this by building an
    inverter when several perfectly good products are currently available.
    As I said above, I use the Kensington Auto/Air Power Inverter. This has
    one regular grounded power outlet, and two USB ports. It is the size of
    a pack of cigarettes. It plugs into a cigarette lighter, or auto 12V
    accessory socket, and can use airline "Empower" outlets. Though on
    planes I have flown on recently they have a standard power outlet
    available. < http://us.kensington.com/html/17163.html >

    Targus have an interesting line of inverters for this very purpose.
    They even have a neat one which fits in a standard cup holder.
    < http://thurly.net/0wos >

    At no time do I run my camera, or laptop directly from an AC power
    source anywhere.

    My laptop, a MacBook Pro, and I would assume any other laptop, or
    netbook, requires a power supply between the computer and AC power
    source. I have two, One I keep at home and one which is ready for
    The same goes for my camera. I always have extra batteries, and if I am
    going to need to charge those batteries which need charging I have the
    appropriate charger which can be plugged into the Kensington inverter.
    The same goes for any other USB powered devices such as iPads, which
    can be charged using the USB port.

    There is no current smoothing issue, that is handled by the device's
    power supply.
    Savageduck, Feb 19, 2011
  7. Alan Justice

    Dennis Boone Guest

    If one knows the voltage for the laptop, they could make a 12 to 24 V
    Um, it's not quite trivial. Most boost converters are low-current
    devices. Most laptops these days require between 5 and 8 amps, at
    their nominal input voltage, to operate. That's a lot of current
    for a throw-together project.

    You _can_ get these things, but they're typically the size of your
    laptop's existing power supply. Some laptop vendors actually put
    the functionality in the laptop supplies in the first place. (Dell)
    Otherwise, look at the likes of Targus.

    Dennis Boone, Feb 19, 2011
  8. Alan Justice

    Paul Furman Guest

    I've had a couple 300w/1000w? inverters like the ones in the following
    link, for around $100 and they are quite noisy but you need something
    pretty big & powerful to charge DSLR batteries while running a laptop
    and some 12v lights all evening in a camper van. Cell phones & batteries
    will charge on very very small low power inverters.

    Paul Furman, Feb 19, 2011
  9. Alan Justice

    Alan Justice Guest

    I have a workhorse for my images. It isn't on the internet, for protection.
    I generally get the image right in the field, so I do minimal Photoshopping.

    One reason to replace my computer on the internet is that OE6 does not
    handle some of the graphics, so some sites are not accessible, and I can't
    upgrade using Win 98, which I can't upgrade with low RAM etc. I have
    Charter cable for TV, but I get such awful service that I won't give them
    more money for internet. If I need better internet acces temporarily, such
    as uploading images to my website, I go to a public computer nearby. So I
    figure I could get a portable computer to use at home and on the road. I
    only need a display that is good enough for reviewing in the field. So
    what's the difference between a "netbook," a "notebook," and a "laptop?"
    (For someone who started computer programming in 1969, I sure haven't kept
    Alan Justice, Feb 19, 2011
  10. Alan Justice

    Savageduck Guest

    I had a full camper/RV setup I would probably go that route.

    As always, it depends on the load you intend to place on the inverter.
    Running lights and a full load charging and computing operation is one
    thing. Having a means to charge DSLR batteries and/or a laptop when
    needed is a little less demanding.
    I get a good 4 hours from my MacBook Pro and I am not going to be using
    it for that sort of time away from the comforts of home. The power
    supply demand for it is 85W.
    The little Kensington I use now with a measly 120W (150W peak) seems to
    charge EN-EL3e's & EN-EL4a's without issue. The MH-21(EN-EL4a) charger
    requires 23W and the MH-18a (EN-EL3e) requires 15W.

    When I have needed to charge a DSLR battery and my MacBook Pro at the
    same time The Kensington has done just fine. Got a little warm, but
    Any extended use, beyond emergency charging and I would consider
    something with a little more muscle.
    Savageduck, Feb 19, 2011
  11. Alan Justice

    Savageduck Guest

    Yup! An upgrade is needed.
    "notebook" and "laptop" are basically interchangeable terms. These can
    be a very usable one machine solution for many users, given the right

    A netbook is usually a stripped down, reduced spec. & power portable.
    Usually displays run from 5 to 12 inches. There is usually no optical
    drive, and hard drive space is limited. Depending on netbook you may
    not be able to use some image editing software.

    I too am a Charter Cable subscriber, and have no issues with their
    broadband, or TV where I am. For me it is a case of Dial-up in a
    desperate emergency only, I haven't used dial-up for many years now.
    You might want to give them a try with their internet service.
    Savageduck, Feb 19, 2011
  12. Alan Justice

    Alan Justice Guest

    Alan Justice, Feb 19, 2011
  13. Alan Justice

    Alan Browne Guest

    What I suggested is _not_ an inverter but a much more energy efficient
    solution that avoids taking DC to AC and then back to DC again in,
    wasting energy along the way. Auto cigarette inverters are pathetically

    A DC to DC converter is MUCH more efficient than any inverter system (a
    DC to DC converter in fact does 'invert' but at a much higher frequency
    - power losses are much less than in a cigarette lighter inverter. And
    using 24 V (series) at the input will result in less loss than using 12V
    [judging by the temperatures I've gotten with wide input range inverters]).

    For the battery solution that Paul suggests, using an inverter to then
    convert to DC is just plain wasteful - and if you're going to be in the
    boonies any length of time and depending on batteries, just silly.

    An other option would be something like a Honda 1000 W generator.
    Quiet, pretty efficient, light. (We've used them for all manner of
    field testing (1000, 2000W versions).
    Alan Browne, Feb 19, 2011
  14. Alan Justice

    Alan Browne Guest

    Who said "boost converter"?

    5 - 8 amps? Why? Most laptops run around 30 - 50 W. So at 18V or so
    that would be a measly ~3A output.

    DC-DC converters are what are in the power bricks for laptops: Xfrmr
    takes 100 - 250 VAC down to 18 - 36, thence a bridge rectifier, thence
    into the DC:DC converter and out to the laptop at the desired voltage.


    is an example of a basic DC:DC converter. For a laptop the "micro"
    would do with the supplier configuring it for the desired voltage.

    We've put these together for field demos (unattended systems with solar
    to battery - no inverters at all - just a good charge controller to the
    batteries). Assign it to a bushy tailed tech, tested it and off it
    went. Other option is to assign it to whatever engineering coop student
    happens to be chained to a desk.
    Alan Browne, Feb 19, 2011
  15. Alan Justice

    Bill Graham Guest

    That must be what the local bands use when they play gigs at our Saturday
    Market and the parks.....It is amazingly quiet, and yet puts out enough
    power to drive the amplifiers that these groups use.
    Bill Graham, Feb 20, 2011
  16. Alan Justice

    Noons Guest

    Alan Justice wrote,on my timestamp of 20/02/2011 5:50 AM:

    For your purposes there is not much difference nowadays, other than capacity of
    disks and screen size. Rules of thumb (not to be cast in stone):

    netbooks: small 10" screen, disk around 150GB mark, memory at around 1GB.
    Very light, great for saving images on the road and for quick presentations but
    little else. They usually have great connectivity.

    notebook: medium 13" screen, disk around 300GB, memory at 2GB.
    Mostly for portable use like a netbook, but in a pinch can do desktop work.

    laptop: 15" and larger screen, disk starting at 500GB, memory starting at 4GB.
    With care in selection of desktop screen, it can replace a desktop computer for
    most folks. It is a heavy beast though, so don't count on carrying it in a hand

    As to which can replace a general purpose desktop, I'd go for a laptop. Mine is
    also a Samsung but with 1TB of disk, 8GB of memory, 64-bit Win7 and a corei5
    cpu. It's a beast but I run multiple virtual boxes inside it for database
    testing, so that's a special need. It was relatively cheap, considering the
    specs. You don't want to know about my desktop...

    However, I don't think any laptop out there will do a good job for colour
    handling with a native screen, with some very rare - and expensive! -
    exceptions. If you want to do even average image editing you'll need a good
    desktop screen to connect the laptop to, with correct profiles and colour
    balanced. That is expensive, so be prepared for the hit. You don't need an
    Eizo Flexscan, but a mall special won't do either.

    Having said that, with patience and care you can get pretty near to a good setup
    by just loading the appropriate profiles for whatever desktop screen you pick,
    taking care to check it on some of the sites used for colour testing and
    balancing the lot with something like Adobe Gamma, which comes free with
    Photoshop Elements. I used a similar setup for years and it works fine.

    Just be aware that a laptop used as a desktop will never be as fast as a same
    generation dedicated desktop. But if all you want is the occasional internet
    access and basic to medium image processing, then it works perfectly fine.

    Count on a grander and a half for the laptop and half a grand for the screen,
    plus ancillary bits and pieces. But of course prices vary wildly and you may be
    able to get a much better deal.
    Noons, Feb 20, 2011
  17. Alan Justice

    Alan Browne Guest

    Oops. 100 - 250 down to about 12 - 30 VAC, thence ...
    Alan Browne, Feb 20, 2011
  18. Alan Justice

    Dennis Boone Guest

    Who said "boost converter"?

    Automobile electrical systems put out 12-15 volts DC. Most laptops
    these days want 18-19 volts. Sounds like a boost converter to me.
    Actually, most current laptop ship with 60-90+ watt supplies, depending
    on whether you want them to charge and operate at the same time.

    If you're starting with 12V and require 18V output at 90W, it's pretty
    easy to need 8A input.

    I'd guess netbooks are a somewhat lighter load, though I haven't
    looked it up.

    Dennis Boone, Feb 20, 2011
  19. Alan Justice

    Alan Browne Guest

    And they're over rated to the need by a good margin.
    In the case that Paul outlined I suggested two batteries in series which
    would cut the current by 2 at the input. Not that it's needed.

    (For the particular Vicor modules I linked to, it's not possible to
    "user define" a 12 V input for a specific voltage output, 18 V minimum
    input is needed. So a series of two batteries is ideal).

    Most laptops I've seen work below 60W. There are those big honkers that
    likely go up to 100W - maybe more.... but taking one of those on a trip
    seems insane to me unless I'd be in one hotel for a week or more. Even
    then, lugging it to/through the airport would be a disaster, esp. with a
    couple plane changes enroute.

    We have a monster hp laptop at work, I'll try to look at its brick tomorrow.
    Alan Browne, Feb 20, 2011
  20. Alan Justice

    whisky-dave Guest

    But those in car computers and devices are protected from such things
    Those usually mains devices aren't expecting the 'rough' voltage
    waveforms most
    inverters supply, in fact you can buy special inverters called pure
    sine wave or modified sine wave
    which of course are usually much more expensive.


    Similar to the UK I guess, it's similar for boats IIRC.
    whisky-dave, Feb 21, 2011
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.