b&m lighting article

[strmrdr]

The part that caught my eye was: "The three lighting options over showcases include Par-38 for recessed fixtures. For higher ceilings try MR-16 halogens from suspended pendants. Metal halides are the more powerful alternative. “Remember, showcase light should be, on average, 10 times more powerful than ambient lighting,” Peterson said."

http://www.jckonline.com/article/CA6661802.html

 

[Serg]

Karl, Thanks for link

re:“A 70 watt ceramic metal halide with a CRI [Color Rendering Index] over 90 and a temperature of 4,000K to 4,200K is perfect for diamonds,” said Peterson. “Anything cooler [over 4,500K] can give diamonds a bluish tint. Anything warmer [less than 4,000K] can give diamonds a yellowish tint.”

It is very strange for me

 

[Garry H (Cut Nut)]

And:

Peterson suggested T-5 or T-8 fluorescent tubes positioned at the top back of the inside showcase. Retailers are moving toward LED technology, but Peterson cautioned that powering such lighting is costly.

That is crazy - LED uses almost no power.

My assisatant decided I should go to a different presentation - she worked out this person did not have deep knowledge

 

[strmrdr]

seemed strange to me too, but 70 or 150 watt ceramic metal halide is the most common spot light I see in jewelery stores.
They are typically CRI 88-92 and 4000k to 4200k
I would hate to work near them all day but they do make frozen spit sparkle.

If they could get them I bet they would use 6000k to help hide the yellow.

 

[oldmancoyote]

Date: 6/1/2009 2:27:59 AM
Author: Garry H (Cut Nut)

And:

Peterson suggested T-5 or T-8 fluorescent tubes positioned at the top back of the inside showcase. Retailers are moving toward LED technology, but Peterson cautioned that powering such lighting is costly.

That is crazy - LED uses almost no power.

My assisatant decided I should go to a different presentation - she worked out this person did not have deep knowledge

Power - yes. Control circuitry - no.

 

[Garry H (Cut Nut)]

Date: 6/1/2009 6:12:37 AM
Author: oldmancoyote

Date: 6/1/2009 2:27:59 AM
Author: Garry H (Cut Nut)

And:

Peterson suggested T-5 or T-8 fluorescent tubes positioned at the top back of the inside showcase. Retailers are moving toward LED technology, but Peterson cautioned that powering such lighting is costly.

That is crazy - LED uses almost no power.

My assisatant decided I should go to a different presentation - she worked out this person did not have deep knowledge

Power - yes. Control circuitry - no.

we use old phone chargers

 

[strmrdr]

Date: 6/2/2009 1:58:29 AM
Author: Garry H (Cut Nut)
we use old phone chargers

yea power supplies are a dime a dozen.

Some of the newer 3W and 5W(and higher) leds require constant current supplies which can be expensive but the common 5mm leds and a few of the higher power ones are cheap and cheap to power.

 

[strmrdr]

Driving this monster would be expensive.
9A constant current at ~3.6V

http://www.luminus.com/stuff/contentmgr/files/0/49fb13dd1ecd06ba454cc7714a96b032/miscdocs/pds_001342_rev_02_sst_90_w_product_datasheet_illumination.pdf

13.5A constant current at ~3.4V
http://www.luminus.com/stuff/contentmgr/files/0/7c8547b3575bcecc577525b80d210ac7/miscdocs/pds_001314_rev_02__cst_90_w_product_datasheet_illumination.pdf