Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens
of my Minolta Z6 through the center. I have in fact, an adapter tube for
this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? Of course, I'm not worried about getting hours
and hours of use out of a battery. It would just be nice to be able to
take a few shots away from an outlet, and a small battery I could rubber
band to the light right would be great. I am interested in trying to use
a 9v battery because they are more widely available than the small 12v
batteries. But don't know enough to know if the lower voltage might
somehow damage the circuitry. Anyone venture an answer?

Thanks,


Jon

Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens
of my Minolta Z6 through the center. I have in fact, an adapter tube for
this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? Of course, I'm not worried about getting hours
and hours of use out of a battery. It would just be nice to be able to
take a few shots away from an outlet, and a small battery I could rubber
band to the light right would be great. I am interested in trying to use
a 9v battery because they are more widely available than the small 12v
batteries. But don't know enough to know if the lower voltage might
somehow damage the circuitry. Anyone venture an answer?

You won't hurt anything, but it may not work and
9v batteries are notoriously inefficient at converting
money to power.

I would use one of these and 8 AA cells. Radio
Shack might even have them.

http://search.digikey.com/scripts/Dk...ame=BH48AAW-ND

On 9/17/2010 1:11 PM, Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens of my Minolta Z6 through the center. I have in fact, an adapter tube for this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it might be interesting to take shots outside with this setup. The power supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be other compact 12v batteries, but I was wondering if it's possible to run this off a 9v battery? Of course, I'm not worried about getting hours and hours of use out of a battery. It would just be nice to be able to take a few
shots away from an outlet, and a small battery I could rubber band to the light right would be great. I am interested in trying to use a 9v battery because they are more widely available than the small 12v batteries. But don't know enough to know if the lower voltage might somehow damage the
circuitry. Anyone venture an answer?

This would be a great use for your spare 12V drill battery.

I was faced with a similar problem. I gutted a broken charger
and used it to power a project in the field.

http://www.metalworking.com/dropbox/PowerOut.txt
http://www.metalworking.com/dropbox/PowerOut.JPG



--Winston

On Sep 17, 1:11*pm, Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, a great investment!http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens
of my Minolta Z6 through the center. I have in fact, an adapter tube for
this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? Of course, I'm not worried about getting hours
and hours of use out of a battery. It would just be nice to be able to
take a few shots away from an outlet, and a small battery I could rubber
band to the light right would be great. I am interested in trying to use
a 9v battery because they are more widely available than the small 12v
batteries. But don't know enough to know if the lower voltage might
somehow damage the circuitry. Anyone venture an answer?

Thanks,

Jon

The lower voltage will not "hurt" the LEDs, but all may not light up
at the same intensity. I have LED light bars installed under the
cupboard over our breakfast table and when building the AC power
supply for them, used an adjustable DC power source. I never measured
the voltage, but as I ran the voltage up from zero to 12 volts and
back down, I saw a number of LEDs that winked out, or were off, while
others were on. At 12 volts all were on.

White "LEDs" are not really white LEDs. Each device contains at least
two UV leds. Sometimes on a white LED that doesn't meet spec, you can
see a more blue light. The UV then excites a covering of exotic
material that does emit what we see as white light. Exactly the same
process as the fluorescent light tubes in your shop lights. The
mercury vapour arc supplies the UV for them.

So, when LEDs are operated at a lower voltage, you will not get the
same quantity of light and it may be a different color temperature
than when running at 12 volts, if that will effect your photography.

Paul

On Sep 17, 4:11*pm, Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, ...
...However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? ...
Thanks,

Jon

20mA is an overload for a 9V battery. I'd try two Radio Shack 4x AA
holders.

jsw

On 9/17/2010 4:11 PM, Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens
of my Minolta Z6 through the center. I have in fact, an adapter tube for
this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? Of course, I'm not worried about getting hours
and hours of use out of a battery. It would just be nice to be able to
take a few shots away from an outlet, and a small battery I could rubber
band to the light right would be great. I am interested in trying to use
a 9v battery because they are more widely available than the small 12v
batteries. But don't know enough to know if the lower voltage might
somehow damage the circuitry. Anyone venture an answer?

Before you put too much effort into it, take a look at Rat Shack item
270-407, $1.89 at a store near you, plus the price of 8 AAs. With a set
of good NiMH batteries it should run your ring light for several hours.

If you need more juice than that you can get a tractor battery for under
30 bucks at Sears or less than that if you shop around.

I hope... I just spent a totally stupid amount of time on this.
Found a single cell battery holder at RS that takes the 12v batteries
commonly used in garage door openers. So I hacked and whacked an
aluminum tube with delrin end caps. Cut up an appropriate power plug,
trimming away all the co-molded plastic and pressing it into one end
cap, which in turn is pressed into the tube. Leads for the battery
holder were soldered before assy. Tapped the back of the tube with an
11/16-20 tap I just happened to have, and then hand chased something
that resembles a mating male thread on the end cap. No power switch as
the ring light has it's own. I will make a light slip fit cap just to
make sure it never gets shorted when not in use. Plugged it into the
ring light, and it works perfect!

Now to sacrifice a battery and see just how long it'll keep it lit at
full brightness... I'll take a pic of the sucker and post to the drop box.

Thanks for all the comments and suggestions.


Jon

On 9/17/2010 5:09 PM, Jon Anderson wrote:

Now to sacrifice a battery and see just how long it'll keep it lit at
full brightness... I'll take a pic of the sucker and post to the drop box.

Ah crap. What a friggin waste of time, there's not enough life to make
my tiny power supply useful for more than maybe 3-4 quick shots. Back to
RS for the 8 cell AA battery holder... I -so- wanted something small and
compact that could attach directly to the light ring. Sigh...

I'll make some sort of housing for the above setup, and probably use the
tripod mounting screw hole to secure it to the camera.


Jon

On 9/17/2010 9:02 PM, Jon Anderson wrote:
On 9/17/2010 5:09 PM, Jon Anderson wrote:

Now to sacrifice a battery and see just how long it'll keep it lit at
full brightness... I'll take a pic of the sucker and post to the drop box.

Ah crap. What a friggin waste of time, there's not enough life to make my tiny power supply useful for more than maybe 3-4 quick shots. Back to RS for the 8 cell AA battery holder... I -so- wanted something small and compact that could attach directly to the light ring. Sigh...

I'll make some sort of housing for the above setup, and probably use the tripod mounting screw hole to secure it to the camera.


Jon


I'm guessing you have 16 parallel strings of 4 LEDs (plus resistor).
So figure say 320 mA at 12 V.

Perhaps an hour with 8 alkaline AA's before you
see a significant light level reduction.

--Winston

--
I pride myself on my unimportance.
(One must excel at something, or what
is a Heaven for?)

On 9/17/2010 10:04 PM, Winston wrote:

Perhaps an hour with 8 alkaline AA's before you
see a significant light level reduction.

That would be more than enough time for anything I anticipate doing
beyond reach of an outlet!


Jon

On 9/18/2010 6:31 PM, Jon Anderson wrote:
On 9/17/2010 10:04 PM, Winston wrote:

Perhaps an hour with 8 alkaline AA's before you
see a significant light level reduction.

That would be more than enough time for anything I anticipate doing beyond reach of an outlet!


Jon

Cool!
http://www.datatoys.com/products/Pro...duct_info.html

--Winston

--
I pride myself on my unimportance.
(One must excel at something, or what
is a Heaven for?)

On Fri, 17 Sep 2010 20:02:39 -0800, Jon Anderson
wrote:

On 9/17/2010 5:09 PM, Jon Anderson wrote:

Now to sacrifice a battery and see just how long it'll keep it lit at
full brightness... I'll take a pic of the sucker and post to the drop box.

Ah crap. What a friggin waste of time, there's not enough life to make
my tiny power supply useful for more than maybe 3-4 quick shots. Back to
RS for the 8 cell AA battery holder... I -so- wanted something small and
compact that could attach directly to the light ring. Sigh...

I'll make some sort of housing for the above setup, and probably use the
tripod mounting screw hole to secure it to the camera.


Jon

Think about the film camera motor drives. The bulk of the drive was a
battery box that bolted on the bottom of the camera.

Cheers,

John D. Slocomb
(jdslocombatgmail)

On Fri, 17 Sep 2010 20:02:39 -0800, Jon Anderson
wrote:

On 9/17/2010 5:09 PM, Jon Anderson wrote:

Now to sacrifice a battery and see just how long it'll keep it lit at
full brightness... I'll take a pic of the sucker and post to the drop box.

Ah crap. What a friggin waste of time, there's not enough life to make
my tiny power supply useful for more than maybe 3-4 quick shots. Back to
RS for the 8 cell AA battery holder... I -so- wanted something small and
compact that could attach directly to the light ring. Sigh...

I'll make some sort of housing for the above setup, and probably use the
tripod mounting screw hole to secure it to the camera.

Jon, put a 7Ah battery in a belt pouch, divvy up the voltage to your
proper flavor, and run leads to the light ring using 3.5mm connector
jack & plug. Instant 6-8 week supply!

--
Some people are like Slinkies ... not really good for
anything, but you can't help smiling when you see one
tumble down the stairs.

On 9/18/2010 5:05 AM, Larry Jaques wrote:

Jon, put a 7Ah battery in a belt pouch, divvy up the voltage to your
proper flavor, and run leads to the light ring using 3.5mm connector
jack& plug. Instant 6-8 week supply!

Well that would do it for sure! But overkill for what I was thinking
about. The light really isn't the right 'color' for 'real' photography.
I was just thinking of the time I took my Escort apart after dropping a
valve seat. There was one (and only one!) ding on top of the piston.
Took several tries to get a decent shot of it. A portable ring light
would have been perfect there.

Thanks,


Jon

On Sat, 18 Sep 2010 17:35:01 -0800, Jon Anderson
wrote:

On 9/18/2010 5:05 AM, Larry Jaques wrote:

Jon, put a 7Ah battery in a belt pouch, divvy up the voltage to your
proper flavor, and run leads to the light ring using 3.5mm connector
jack& plug. Instant 6-8 week supply!

Well that would do it for sure! But overkill for what I was thinking
about. The light really isn't the right 'color' for 'real' photography.
I was just thinking of the time I took my Escort apart after dropping a
valve seat. There was one (and only one!) ding on top of the piston.
Took several tries to get a decent shot of it. A portable ring light
would have been perfect there.

I was going to say "Wow, that would have been the right time to go buy
one of the inspection cameras on a stick." but you had to pull the
head anyway.

http://www.harborfreight.com/wireless-inspection-camera-with-24-inch-color-lcd-monitor-66550.html

--
Some people are like Slinkies ... not really good for
anything, but you can't help smiling when you see one
tumble down the stairs.

On Fri, 17 Sep 2010 12:11:59 -0800, Jon Anderson
wrote:

Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens
of my Minolta Z6 through the center. I have in fact, an adapter tube for
this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? Of course, I'm not worried about getting hours
and hours of use out of a battery. It would just be nice to be able to
take a few shots away from an outlet, and a small battery I could rubber
band to the light right would be great. I am interested in trying to use
a 9v battery because they are more widely available than the small 12v
batteries. But don't know enough to know if the lower voltage might
somehow damage the circuitry. Anyone venture an answer?

Thanks,


Jon

LED's want constant current drive, not constant voltage. Typical
voltage for a white LED is about 3.3 volts at rated current, but this
can vary. One LED might be quite happily running its rated 30 mA (or
whatever) at 3.3 volts while the one next to it may only want 3.2 and
3.3 would overdrive it.

So there is one or more dropping resistors somewhere, or 1 or more
current regulators, either in the light or in the wallwart. Better
figure out what the story is before just substituting a battery for
the wallwart.

Your light is some arrangement of parallel-connected series strings of
LEDs. Since there are 64 LEDs it might be 16 strings of 4 LEDs --
but, ya never know. It could also use electronics in the light itself
to produce constant current at elevated voltage to accomodate more
LED's per string. There are a lot of chips on the market now to do
exactly that, so I won't venture to guess -- but if your device does
use such chips then 12VDC from a battery should be OK.

Simple checks you could do: operate the light and wallwart very close
to an AM radio tuned between stations. If you hear an increase in
noise, there's a switchmode regulator in there somewhere and you'd
probably be OK running it with 12VDC.

Operate it from a variable bench supply (or have a sparky friend do
that) and monitor voltage and current as you increase from 0 to 12
volts. If the current doesn't increase rapidly in a region somewhere
around 12 volts and the brightness looks right, you're good to go
with 12 volts.

You are gonna love that light. I made an LED ringlight years ago for
my scope that I really like. I had a rather expensive professional
fluorescent ringlight (that I got at an auction for a song) but I like
the LED ring a lot better. Contrast is markedly better, brightness is
controllable and it's small enough that it doesn't get in the way.

On 9/17/2010 8:31 PM, Don Foreman wrote:

You are gonna love that light. I made an LED ringlight years ago for
my scope that I really like. I had a rather expensive professional
fluorescent ringlight (that I got at an auction for a song) but I like
the LED ring a lot better. Contrast is markedly better, brightness is
controllable and it's small enough that it doesn't get in the way.

Already do love it! I have a B&L Stereozoon, .7 - 3, on the B&L boom
stand. It's a really nice rig. Dad loaned me one years ago when I had a
Levin lathe. It was awesome, being able to touch off a tool and put a
..002 chamfer on something. But never did quite like the stock light.

Got this scope at a yard sale on a base with dual slides for $100, Dad
gave me the boom stand. It's a nice setup, and the ring light works SO
well I'm kicking myself for being a tightwad and not buying one sooner.
I can probably get $100 for the base alone on ebay, and now I can sell
my imported microscope, so the whole setup will come out to essentially
near free.


Jon

The best thing to use is a back strapped FET that was once used
as a constant current pass unit - but now they have 'current regulators'
that are fets with the gate and resistor (variable by trimming) back to
the source IIRC. These are sold in two lead diode looking things.

e.g. 24ma the voltage has to be high enough to conduct and it functions.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator & Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 9/17/2010 11:31 PM, Don Foreman wrote:
On Fri, 17 Sep 2010 12:11:59 -0800, Jon Anderson
wrote:

Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

Looking at the large ID of this, I realized I could easily poke the lens
of my Minolta Z6 through the center. I have in fact, an adapter tube for
this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to run
this off a 9v battery? Of course, I'm not worried about getting hours
and hours of use out of a battery. It would just be nice to be able to
take a few shots away from an outlet, and a small battery I could rubber
band to the light right would be great. I am interested in trying to use
a 9v battery because they are more widely available than the small 12v
batteries. But don't know enough to know if the lower voltage might
somehow damage the circuitry. Anyone venture an answer?

Thanks,


Jon

LED's want constant current drive, not constant voltage. Typical
voltage for a white LED is about 3.3 volts at rated current, but this
can vary. One LED might be quite happily running its rated 30 mA (or
whatever) at 3.3 volts while the one next to it may only want 3.2 and
3.3 would overdrive it.

So there is one or more dropping resistors somewhere, or 1 or more
current regulators, either in the light or in the wallwart. Better
figure out what the story is before just substituting a battery for
the wallwart.

Your light is some arrangement of parallel-connected series strings of
LEDs. Since there are 64 LEDs it might be 16 strings of 4 LEDs --
but, ya never know. It could also use electronics in the light itself
to produce constant current at elevated voltage to accomodate more
LED's per string. There are a lot of chips on the market now to do
exactly that, so I won't venture to guess -- but if your device does
use such chips then 12VDC from a battery should be OK.

Simple checks you could do: operate the light and wallwart very close
to an AM radio tuned between stations. If you hear an increase in
noise, there's a switchmode regulator in there somewhere and you'd
probably be OK running it with 12VDC.

Operate it from a variable bench supply (or have a sparky friend do
that) and monitor voltage and current as you increase from 0 to 12
volts. If the current doesn't increase rapidly in a region somewhere
around 12 volts and the brightness looks right, you're good to go
with 12 volts.

You are gonna love that light. I made an LED ringlight years ago for
my scope that I really like. I had a rather expensive professional
fluorescent ringlight (that I got at an auction for a song) but I like
the LED ring a lot better. Contrast is markedly better, brightness is
controllable and it's small enough that it doesn't get in the way.

Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, a great investment!
http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337

I make my own ring lights. 8 white LEDs from Digi-Key, under $10. A
piece of scrap PC board material,
cut an ID and OD. Then, make a circular cut in the foil, and you have
two conductors running all the way
around. Put a current limiting resistor in series with each LED, and
hook a suitable wall-wart to it.
No active circuitry other than the LEDs themselves.
Looking at the large ID of this, I realized I could easily poke the
lens of my Minolta Z6 through the center. I have in fact, an adapter
tube for this camera allowing me to use my collection of 52mm filters.
I'm making an adapter to mount the LED ring light to this adapter tube.
For most uses, I would just use the wall wart power supply. However it
might be interesting to take shots outside with this setup. The power
supply is a 12v 500mA.

Remote garage door openers use a small 12v battery, and there might be
other compact 12v batteries, but I was wondering if it's possible to
run this off a 9v battery? Of course, I'm not worried about getting
hours and hours of use out of a battery. It would just be nice to be
able to take a few shots away from an outlet, and a small battery I
could rubber band to the light right would be great. I am interested
in trying to use a 9v battery because they are more widely available
than the small 12v batteries. But don't know enough to know if the
lower voltage might somehow damage the circuitry. Anyone venture an
answer?

Extremely unlikely you'd cause any damage to any circuitry in the ring
light as long as you make sure the polarity is right.
But, a 9 V "transistor radio" battery is good for about 10 mA, max. At
500 mA drain, it would probably drop to 2-3
volts within seconds. They are rated at 120 - 150 mAH, so even if the
internal resistance didn't make it not work,
you'd only get a couple minutes battery life out of it.

Jon

On Sep 17, 1:11*pm, Jon Anderson wrote:
Bought an LED ring light for my B&L microscope, a great investment!http://cgi.ebay.com/ws/eBayISAPI.dll...m=400017698337


The power supply is a 12v 500mA.

The power supply is a switching supply, since it automatically changes
from 120 to 240 VAC input. I'm sure that all the LED drive circuitry
is in the ring light itself based on the variable illumination
feature. http://store.amscope.com/led-64s-yk.html

If the unit actually draws anything near 500 mA, a set of alkaline AA
cells (which are rated at 1700 mAh or more) should power it for more
than a half-hour to as much as an hour under practical conditions.

Northe