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StefanMunteanu
02-24-2009, 10:30 AM
Hello,

I've allmost finished my diy diva kitt. Worked a loat for it(since I want to build it as good as I can).
My next diy project would be a led based light source - for inside a car type of shooting. I've found so far:
Osram:
LED,OSTAR,hexagon,5600K- 18w and 27 w (uau!)

their only problem is their realtively low CRI : 80.

and this:
http://www.seoulsemicon.com/en/product/prd/topviewLED.asp

I don't know what power, I don't know the exact colour temp but they have two led models with 91 CRI (Thats what they say) .

This being said. What would you recomend? Will the Osram do? Will I be able to shoot on film with them(and not have problems with green)?
Do you know other types of led? (and care to tell 'em)

Thank you,
Stefan

P.S.: Maybe this has been talked before, sorry (hey on dvxuser by now everything has been talked before)

NoNoob
02-24-2009, 02:55 PM
I use the OSRAM products- nice quality.
I also use a handful of 'stick up' type 3 LED/3AAA powered lamps for a variety of purposes.
They work just fine and I don't care about CRI so much- they're just little fill ins.
Usually cover them with a diffuser of some kind or opaque white.

Shot an HOUR long piece with just four of the 'stick up' units, because I couldn't use any AC in the location and it was a temple.
They were perfect for the scene.
Any mild adjustment required to pull it back from a tint (mine were a slight blue cast), just ran it through COLOR one time and it was like it never happened.
Maybe .7 degree adjustment, if that. Tiny steps brought it right in line.
Thankfully I didn't have to mix it with any daylight or other light sources.

Looked fine- was very effective, and the monks didn't mind the mild intrusion.

I recently built a bank of OSRAM 12V 35W 'little' bulbs (quartz).
Run it off a cigarette plug for car shots.
Put a little switch on each of the five bulbs- and 'pick' my illumination for the setting that way.
Excellent results.

Idea being- you want (need) the extra light- but you don't want it to look like you're using any.
Balance between the two.

Good luck.
YES- everything has been talked about, and it's coming 'round again. No worries!

StefanMunteanu
02-24-2009, 04:13 PM
I also find Osram the best option. I was just wondering if the CRI of 80 will affect the ability of mixing it with daylight. I plan to use them during the day (nights also...) in a car in order to have proper exposure on the exterior on the window (dunno if what I said makes sense). Anyway the question is, will the Osrams do it? Their quite pricey and I wouldnt wanna throw that cash on the window :)(an overexposed car window). I would go Osram myself, I just don't really trust no name companyes. I might be wrong but I would spend the extra cash if it works - I can trust that the technical specs Osram give are accurate.
Nevertheless thank you for your answer I apreciate it.
Problem is I'm located in Romania and the Osram dealer doesnt have them , and I cannot buy just one and do a test. I have to know if they work before spending 250 euros.

Thanks again,
Stefan

NoNoob
02-24-2009, 09:03 PM
Yow! 250E for one of the OSRAM 12V items? That seems way too steep.

Perhaps we're 'speaking' of different items here?

The ones I use are very small, with two prongs for power leads.
About the size of your little finger nail? Same items??

Every day I use a pair of them to shoot a time lapse sequence i've been working on for about eight months.
They produce a wonderfully clean and bright light that is perfectly fine for all kinds of shooting.
(of course, my application is in a controlled, indoor environment- and not like shooting in the automobile like you plan.)

Romania- a wonderful place with excellent food! You're lucky!!
And, of course, the women are beautiful!!

If you have an interest in these 12V bulbs- let me know- I could always send you one to test with.
No problem.

StefanMunteanu
02-25-2009, 07:25 AM
So,

We romanians have the most healthy distroing food - but man its tasty:)
We romanians have the most easy women - but man their beautifull :)

There's a saying around here:
Romania is such a beautifull country, too bad romanians live in it...

Back to the subject. Here it is:
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=6491373

Its not 250 euros, but our dealer wont bring from uk less then 10 pcs. So If I buy I have to drop some cash for it. Is it the same one you use? You think they wont make it in such a situation - in a car by day?
Maybe you could post some grabs or maybe footage with what you use them for, If that is possible ofcourse.

Thank you again for the answer,
Stefan

NoNoob
02-25-2009, 02:21 PM
No, different item altogether- Sorry.

Here's a link to the item I'm speaking of:

http://www.elightbulbs.com/catalog_product.cfm?source=GoogleBaseCSE&prod=QQ64432

I build the mounting board, do all the wiring, and make the plugs for the power supply to it.
I have these little SPDT switches I put in the circuit so I can flip on one or more at a time.
I've considered putting in a small potentiometer so I can ramp the voltage up or down (with all on).
I fashioned a diffusion cover out of a busted bathroom light lens- opaque white.
It provides a nice, diffused glow.

I'll try to dig up a shot or two and post it here.

Sorry we're on different wave lengths here.
Not much help in the final analysis I guess.

Yes, I've heard that saying as a matter of fact... from a Romanian woman I dated for a short while.

StefanMunteanu
02-25-2009, 03:37 PM
Hello again,

Yes we are talking about a different item here. Thats not a Light emiting diode(led) its an incandescent light... Very much different.
I''l keep on searching the net. I'll find that answer. Thank you annyway.
Stefan