One P7 Led or 3 x P4 Leds ?

[Mark1982]

Hi guys,
I've a fuzzy question...

Which is the better situation between the two one listed below ?

I'm looking for the best solution in order to obtain an highly penetrating luminous narrow beam...



Case A)

One Seoul P7 Led, driven at 2800 mA costant current,
together with this 12° reflektor
(see the .pdf test report at the end of the page, but notice that test may have not been made with a P7 led):

http://www.optomarket.com/jsp/index.jsp?p_gadgetURL=pagemapping.jsp%3Fid%3Dcatalog_list&p_contentTopic=0000114354&pocs_bnav=yes&p_containerTopic=0000114353




Case B)

3 x Seoul P4 Leds,
each one driven at 930 mA costant current,
together with this 10° triple lens
(see the .pdf test report at the end of the page, but notice that test has been made with P4 leds at only 350 mA ):

http://www.optomarket.com/jsp/index.jsp?p_gadgetURL=pagemapping.jsp%3Fid%3Dcatalog_list&p_contentTopic=0000545864&pocs_bnav=yes&p_containerTopic=0000545863



:twothumbs

 

[yellow]

if the higher mounting effort makes no difference, then the three P4s,
same brightness than the quad but less current (ist just three emitters instead of four),
better focusing with the single emitters.

 

[Wiggle]

Why P4? It's an old bin with not as good efficiency. Perhaps 3 x R2?

 

[rantanplan]

Why P4? It's an old bin with not as good efficiency. Perhaps 3 x R2?

Because he was talking about a SEOUL P4 LED, probably a U2 bin ... and not about a CREE XR-E P4 bin


A triple P4 setup can offer a better beam. A P7 setup may have a small advantage in terms of total output, but the beam would be more floody.

I´m using IMS20 reflectors for the P4 and don´t know how good a triple optics will perform with them. A triple optics is probably cheaper, but (IMHO) single reflectors like the IMS20 (or the Khatod ones) will produce a nicer beam ...

 

[yellow]

A triple optics is probably cheaper, but (IMHO) single reflectors like the IMS20 (or the Khatod ones) will produce a nicer beam ...

with the reflectors considerably better.

 

[Wiggle]

Because he was talking about a SEOUL P4 LED, probably a U2 bin ... and not about a CREE XR-E P4 bin

Oops. brain malfunction

 

[Mark1982]

Great replies,
thank You!

I've alredy bought some Seoul P4 and P7 leds...
I've got them (leds+drivers) here and I only have to buy the lens or the reflektor... so I wouldn't like to buy other led types...

The total price of a P7+driver is quite similar to the price of 3 x P4 + driver...


I'll use the led(s) for a scuba underwatar torch with 3 NiMh batteries in series (2500 mAh for each battery).
I'll switch on the torch only for some minutes in order to have the most penetrating beam...


I don't understand which solution can be better for me (using the Kathod devices)...

Not a matter if the better solution could be the most expensive one...

I've read that 3 x P4 with lens is cheaper and can make a better beam, but I've also read that a P7+reflektor could be more penetrating.. is it right?

 

[yellow]

As far as I understand it, as a diver, You would need a light that is, on the surface, extremely focused and does not offer any spill.

I dont like such lights and thus am not well informed on them, but what You "need" were an aspheric.

With anything else the wider beam + bright spill will reflect on any "things" in the water back on You.
So a P7 light were much worse than the triple.
If You could find some optics, even more focused than Your triple version, that would not hurt.

 

[Mark1982]

Hi yellow,
thank for Your exhaustive reply!

My english isn't so good...
Can You explain me what do You mean with:

...extremely focused and does not offer any spill...

... the wider beam + bright spill will reflect on any "things" in the water back on You...

I've got some underwater torches (in different beam and lenses) for a good global vision and illumination.

Now I'm building a very small torch I'd like to use during my daylight leke immersion (not in night diving) in order to light up small holes I can find into rocks and ravines...

I prefer an highly penetrating and powerful luminous beam, even if it could dazzle back me...

So, with a triple P4 configuration, can I obtain a better vision and a more penetrating flux when I'll go and light up ravines?