Back to the IR light source concept...

[John Fields]

On Tue, 10 Aug 2004 19:48:24 GMT, Don Bruder <dakidd@sonic.net> wrote:

Hmmm... that one has possibilities, though I cringe at the idea of how
much $$ it will take to get ahold of the stuff... When looking at
IR-transmitting photographic filters, I was routinely spotting prices in
the $150-$200/6 inch square range for plastic filters - Which is why I
ended up going with a "make-do" chopped out of a black CD-R. Even the
gell filters (which are very likely to have *VERY* short working
lifespans) to transmit IR were ridiculously priced - a 70MM round was
tagged at $89, fergawdsake! My budget (which is mostly imaginary,
practically speaking) for this project can't even CONSIDER those kind of
prices! And glass? HAH! If I can't afford the "cheap" gells and/or
plastic, then I don't even need to consider glass, since that seems to
routinely be about 130-200% more expensive than the corresponding
plastic filter.

Now to see if I can find someplace that will tell me how much this
"Acrylite" stuff costs... I note a glaring lack of any reference to
pricing for it at the link you posted. Most often, I've found that
situation to be a red-flag for "If you need to ask "how much?", it's
more than you can afford. Have a nice day, and don't let the door hit
you in the arse as you leave." materials.

---
Cyro makes the stuff, and sells it through distribution, so you may
want to check with one of your local plasic suppliers to see if they
can help you out. Also, Cyro has a list of their distributors on
their web site, so you may want to check that out.
---

Still, now that I know the stuff exists, I might be able to find
someplace that sells it in reasonable quantities, at reasonable prices.
More investigation is in order, obviously...

---
I have a small quantity on hand and, depending on how much you need,
might be able to help you out at my cost plus freight. (Or a straight
swap for a bottle of a decent Chardonnay?-)

Email me if you're interested.

--
John Fields

 

[Don Bruder]

In article <6bhkh052o8ucj063s1ip23qki88aqoqr5f@4ax.com>,
John Fields <jfields@austininstruments.com> wrote:

Now to see if I can find someplace that will tell me how much this
"Acrylite" stuff costs... I note a glaring lack of any reference to
pricing for it at the link you posted. Most often, I've found that
situation to be a red-flag for "If you need to ask "how much?", it's
more than you can afford. Have a nice day, and don't let the door hit
you in the arse as you leave." materials.

---
Cyro makes the stuff, and sells it through distribution, so you may
want to check with one of your local plasic suppliers to see if they
can help you out. Also, Cyro has a list of their distributors on
their web site, so you may want to check that out.
---

Still, now that I know the stuff exists, I might be able to find
someplace that sells it in reasonable quantities, at reasonable prices.
More investigation is in order, obviously...

---
I have a small quantity on hand and, depending on how much you need,
might be able to help you out at my cost plus freight. (Or a straight
swap for a bottle of a decent Chardonnay?-)

Email me if you're interested.

We might just get something going, though it will likely be cash, since
I wouldn't know a decent chardonnay from vinegar if it walked up and
introduced itself to me. I'm basically a teetotaller - the "non
preaching" kind - mainly due to lack of any interest. By my own personal
drinking habits, buying a six-pack of Guinness, or, in a pinch, Bud
long-necks, and killing it off inside of six months qualifies as a
"major bender".

Keep an eye on your in-box...

--
Don Bruder - dakidd@sonic.net - New Email policy in effect as of Feb. 21, 2004.
Short form: I'm trashing EVERY E-mail that doesn't contain a password in the
subject unless it comes from a "whitelisted" (pre-approved by me) address.
See <http://www.sonic.net/~dakidd/main/contact.html> for full details.

 

[Chris Hodges]

Don Bruder <dakidd@sonic.net> wrote in message news:<vFrSc.6885$54.106708@typhoon.sonic.net>...

Hmmm... maybe it's just me and my misinformation, but I've always been
under the impression that gels are the "cheap to buy this one, but
expensive as hell in the long term due to needing frequent replacement"
solution. My limited time "on the boards" (credited in the program as
"Soldier with a line" - <chuckle&gt in a 6 week run of Jesus Christ
Superstar at a local playhouse showed me a lighting guy *CONSTANTLY*
griping about needing to chase up into the flys to replace gels -
sometimes before each run of the show, and particularly the reds. From
that, I reached the conclusion that gels are, at best, a "make-do",
rather than a permanent solution. And the prices... <choke> At one
point, I overheard him saying something like "There goes another hundred
bucks" while he was working on cutting a blue one to shape.

He was probably chucking approx 0.5-2kW at the gel, which was
transmitting <10% of the visible light (and not much IR in many
cases). As far as his prices, I don't know - he'd probably just
finished a roll. You should be fine so long as you avoid those linear
halogen "security" type floodlights - they burn all but the high temp
gel.
See
http://www.leefiltersusa.com/LightPrice/LightPriceSheet.html#
for pricing (US)
Looking at the transmission curves in the swatch book, which go up to
800nm, the following 2 combinations could work
141+027
172+198+027

The 027 is a red with ~2% visible transmission.

I don't know about getting hold of some, but $14 at list price doens't
seem too bad - with plenty to spare.

I tried both with a mini maglite, but my digital camera can hardly see
any IR (spot from a recmote control in a darkened room is faint even
if pointed straight at the camera) so I couldn't see anything. Both
combinations appeared dull red - but then so does "invisible" 785nm
laser light.

Chris