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Lux meter tests


reef

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I set up a flat poly sheet with makings at 20cm from centre to test the lux of some lighting.

Luxmeter model is QM1586 Digitech

test are taken at 25cm from lamp cover.

here are the test results.

Since my first test i note that having the meter steadly makes a dramtic differance and test can vary which way the bulbs are facing.

400w.reeflux 12k bulb.using same type of ballast.

readings are:

... ...... centre. 20cm to right. 20cm to front

light 1 62k 43k 29k

light2 65k 43k 30k

light3 68k 39k 28k

light1.jpglight3.jpg

Will look to redo some of my initial tests as they where taken by hand which gave far inconsistant readings. Will be interesting what the 250w bulb reads and to see if bigger reflectors do give better coverage/light power.

did a test outside on sunlight . reading at 10.45am .85k.

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Did some re testing today on some more metal halides. Funny how most of the readings are the same :D not made up.

The test are on inconsistent as it is not an easy process due to many reasons.

For one it depends which reflector you use as the brightest light is not always under the bulb and can be on the side of the bulb.

Also some bulbs are smaller so the side readings are different and can differ due to the centre reading effecting the side reading.

retested wasps tank.

centre means the brightest part of the bulb not directly under it.

400w, narva 400w se.with hps ballast. taken 20cm from light cover

centre, 20cm to right. 20cm to front.

73k .30k . 34k

54k .28k . 32k taken 25cm from light cover.

250w narve 14k 25cm from bulb

.57k .37k .28k

400w blv, 14k. really bright at 25cm

100k .43k .48k

at 20cm high the bulb was reading over 1250k

400w sps, 20k bulb, at 25cm

75k, 27k, 34k.

To get the best light you have to match the ballast with the bulb and get a geometric reflector to match the bulb.

also read that colour of the bulb can change depending which way the nipple is facing.

The blv 14k bulb was by far the brightest and really shows that bulb selection is important.

Also a 250w can be almost as bright as a 400w if the correct bulb is used.

I believe 250w bulbs actually run at 360w anyway so that explains why they are as bright as some 400w units.

will test a 250de sometime as they can give high readings if used in a correct reflector.

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the narva readings look more consistant to the readings i took.

also read that colour of the bulb can change depending which way the nipple is facing

and intensity. if you screw the bulb in so the nipple (?) is facing horizontal (pointing downwards) you get more intensity in the centre as well as the edges of the reflector. having it point sideways or on an angle light is dispersed more unevenly.

i would be interested to see the difference it makes without the lumen arc reflector at all. obviously a reasonable amount, but just how much?

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see the difference it makes without the lumen arc reflector at all. obviously a reasonable amount, but just how much

It does not seem to make much difference as my reflector which are half the size are putting out more light. however i dont have the same bulbs and better equipment is required.

From what i have read diamond reflectors will give you a even spread of light so you dont get any hot spot. the best light is not always under the bulb but on the side of the bulb.

The best bet is always get decents reflector not just paint the inside of the hood :D

Will also see if i can get a true lumenarc to see how it goes against the copies. however bulb & ballast selection will make a bigger differance.

Looking at the true lemenarc the reflector is much brighter so i would assume you will give more light however if it is say 10% does it really matter due to all the variations.

and intensity. if you screw the bulb in so the nipple (?) is facing horizontal (pointing downwards)

Bit hard to do as you have to rotate the mogul to get the nipple in the correct location. the bulbs have to be screwwed in tight so it a bit hard to place the nipple where you want it.

The blv bulbs rock if you want bright bulbs

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Maybe an opportunity for you to make big bucks. :D

I am aware of quiet a few people who use them and some like them some dont as they are very white.

Stopped using them about six months ago as they where too bright, some corals did very well like the purple and blue acros however green looked very washed out.

So for me yes you can have to much light. but hey they are bright.

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