12 Volt LED recommendations?

[Paul Deitch]

I've been posting in the Super8 forum but my question is now specific to scanning/photographing films.
The projector is a Bauer 170 Sound with a 12 volt AC bulb supply.
For testing I am using a 12 volt, 30 Watt equivalent LED that I had lying around.
The original bulb is rated 70 watt.
From those that have done this before, is there a recommended 12 volt LED bulb I should be using or is it not important?
Thanks.

[Nantawat Kittiwarakul]

One thing for sure - your 30w LED would be more than likely to be wayyyyy overkill for the work.

I'm using just 3w LED for my setup, but still have to find ways to attenuate its light output without causing any other collateral issues. 30w would be more than enough to blind your whatever camera you're using I guess.

[Winbert Hutahaean]

One thing for sure - your 30w LED would be more than likely to be wayyyyy overkill for the work.

I think what OP meant was 30w equivalent to incandescent bulb as he wrote "equivalent" in his original post

As this page says a 3W LED = 45W incandescent

https://learn.eartheasy.com/guides/l...20incandescent.

[Orestes Roumeliotis]

As this page says a 3W LED = 45W incandescent

https://learn.eartheasy.com/guides/l...20incandescent.

Yes, but the point being made was that using the wrong type of light would potentially over expose or even complete ruin anything you were using to copy the frames you were copying.

[Nantawat Kittiwarakul]

just realized I've made a goof in my previous post.



What I though to be 3w lamp, is actually 5w ones. No wonder why I got overly excessive light after changing the old LED panel out.

So unless there's a specific reason I think you'd generally need no more than 1-3w LED light source in most setup.

[Paul Deitch]

Great, thanks for all the feedback. I'm enjoying this project. I've been experimenting with a 100mm macro lens on a Canon 5d3 direct into the gate and while the the pic is beautiful it is not filling the frame. What's the recommended next step for this setup to magnify or should I be looking at a different possibility?

[Stan Jelavic]

Is the lens F/2.8? Is so that is a great macro lens with 1:1 magnification.
So here is a simple calculation for you.
Full frame sensor dim 36x24mm
S8 frame size 5.79x4.01mm
Since the magnification is 1:1 you will cover only 5.79x4.01mm out of 36x24.
The resolution then is
length pixels = (5.79/36)*(5760 pixels) = 926
width pixels = (4.01/24)*(3840 pixels) = 641
That is on a shy side and you would need at least 2x optical magnification.
So perhaps the best way for you is to add the extender for 2X.
Also I am not familiar with the Mark3 model (I have Mark2 and use it for telecine) but
double check to make sure that you can run with the mechanical shutter open and what the max resolution is in
that mode.
Anyways have fun with your project.