Another Phil
Member
- Joined
- 1 Jan 2015
- Messages
- 123
Hi folks,
Putting this up here in case anyone finds it useful (and so I have it in one place).
Don't expect any scientific rigour
I replaced a daylight T5 tube with an Arcadia Classica Stretch LED bar
http://www.arcadia-aquatic.com/classica-stretch-led/
and it gives a colder but more realistic feel than the warmer tones of the Realux T5 I had.
I got the camera out and did some tests,
The first images are a colour comparison and the box "lights test" is a brightness test;
https://farm8.staticflickr.com/7641/16589861990_b1bbabbc77_o.png
Colour.
Under-exposed to accentuate colour cast.
As I expected 7 and 8, the 2 domestic household bulbs, are very yellow, but what I didn't expect was how neutral the T5 was; to my eye it seems a welcoming slightly yellow light.
5 is the Arcadia Stretch daylight setting and I'm surprised at the colour cast because to the eye it seems the most neutral/'real'.
6 shows that with the daylight and red both on there is not a big change in red cast and in the tank I can't immediately tell if the red is on or off - only by flicking the switch and looking closely.
Brightness.
All the lights were balanced on chairs above white paper on floor, and camera on tripod.
The surprise here is the Arcadia Stretch LED daylight setting being comparable to the T5+reflector as to the eye it appears a bit dimmer, and with the red on as well it actually shows as brighter, whereas to the eye there is hardly a change.
Provisos;
I appreciate that on my camera 1/24sec registers as 1/20 and 1/26 registers as 1/30, so brightness differences could be less than they appear.
My camera could be overly sensitive to the red spectrum.
I should have used 200iso or higher to be more useful to other cameras doing a brightness comparison.
Conclusions;
The Arcadia Stretch LED gives out more light than it appears. This is sort of confirmed by a Devil's Ivy/Epipremnum aureum which appears as variegated as with the T5.
I couldn't do any other comparison as my tank changed completely between the 2 light systems.
A PAR meter would have made life easier.
I don't have any meaningful growing data except to say that with the bar currently at 18"/450mm above the surface of a 15" deep tank I can grow crypts, anubias and java fern. (After reading Clive's posts about photon torpedoes I almost set the light up in the wardrobe ) I'm starting to lower the light (decrease the height - I think that can cause confusion....), so will see what happens.
And if this post works I'll try and sort out a journal.
cheers phil
Putting this up here in case anyone finds it useful (and so I have it in one place).
Don't expect any scientific rigour
I replaced a daylight T5 tube with an Arcadia Classica Stretch LED bar
http://www.arcadia-aquatic.com/classica-stretch-led/
and it gives a colder but more realistic feel than the warmer tones of the Realux T5 I had.
I got the camera out and did some tests,
The first images are a colour comparison and the box "lights test" is a brightness test;
https://farm8.staticflickr.com/7641/16589861990_b1bbabbc77_o.png
Colour.
Under-exposed to accentuate colour cast.
As I expected 7 and 8, the 2 domestic household bulbs, are very yellow, but what I didn't expect was how neutral the T5 was; to my eye it seems a welcoming slightly yellow light.
5 is the Arcadia Stretch daylight setting and I'm surprised at the colour cast because to the eye it seems the most neutral/'real'.
6 shows that with the daylight and red both on there is not a big change in red cast and in the tank I can't immediately tell if the red is on or off - only by flicking the switch and looking closely.
Brightness.
All the lights were balanced on chairs above white paper on floor, and camera on tripod.
The surprise here is the Arcadia Stretch LED daylight setting being comparable to the T5+reflector as to the eye it appears a bit dimmer, and with the red on as well it actually shows as brighter, whereas to the eye there is hardly a change.
Provisos;
I appreciate that on my camera 1/24sec registers as 1/20 and 1/26 registers as 1/30, so brightness differences could be less than they appear.
My camera could be overly sensitive to the red spectrum.
I should have used 200iso or higher to be more useful to other cameras doing a brightness comparison.
Conclusions;
The Arcadia Stretch LED gives out more light than it appears. This is sort of confirmed by a Devil's Ivy/Epipremnum aureum which appears as variegated as with the T5.
I couldn't do any other comparison as my tank changed completely between the 2 light systems.
A PAR meter would have made life easier.
I don't have any meaningful growing data except to say that with the bar currently at 18"/450mm above the surface of a 15" deep tank I can grow crypts, anubias and java fern. (After reading Clive's posts about photon torpedoes I almost set the light up in the wardrobe
) I'm starting to lower the light (decrease the height - I think that can cause confusion....), so will see what happens.And if this post works I'll try and sort out a journal.
cheers phil
