FlytrapCare Carnivorous Plant Forums

Hi, Just wondering about my lighting situation with my VFT. I see everyone recommends 6500k, which I achieved with some photo filters on a 5000K light bulb.

But what about the strength of the light? I have a light meter. So, I am trying to figure out what the best distance and strength of the light would be.

Where I have it now, I set my meter to ISO 100 and 1/100 Shutter, and it reads Between F/5.6 and F/6.3

Not sure if that's too bright or not enough light.

Any advice?

VFTs grow in full sun, so it's unlikely that it's going to be too much light. Somewhere there's a conversion system (table?) for converting f-stops to foot-candles. If you find it, I can tell you that I always grew mine at around 3500 FC under full-spectrum lights and they colored up nicely.

'Course there's a whole sub-Forum here devoted to lighting...

I will look for it. I must have missed the Lighting Forum... Time to check it out!

Thank you!

Try removing the filter and measure again.
5000K is fine for the plants.
Color is less critical than intensity and all filters give you some light loss.
Full sunlight would give you and exposure of 1/100sec @ f16 for ISO100. ( Sunny 16 Rule )
If measurement is above that, move the lights up a bit further away.
Open shade gives you 1/100sec @ f8 for ISO100.
Your reading is on the low side of adequate, should be fine.

BTW, Incident or Reflected Light meter?

Good growing,
Mike

Shadowtski wrote:Try removing the filter and measure again.
5000K is fine for the plants.
Color is less critical than intensity and all filters give you some light loss.
Full sunlight would give you and exposure of 1/100sec @ f16 for ISO100. ( Sunny 16 Rule )
If measurement is above that, move the lights up a bit further away.
Open shade gives you 1/100sec @ f8 for ISO100.
Your reading is on the low side of adequate, should be fine.

BTW, Incident or Reflected Light meter?

Good growing,
Mike

Hey Mike! Thanks for replying!

The filter takes away about one full stop of light. If 5000k works, then i'll gladly put away my filters and use them for other things.

Completely forgot about the sunny 16 rule, so that was a helpful reminder.

I have a Sekonic Light Meter, It can do either Incident or Reflective, but it's basically the same either way I meter it.
Its also a rainy day here, so no strong light from outside today.

-Shana

Sekonic makes good stuff.
I have an L308 that's 20 - 25 years old.
Still looks and works like brand new.

Good growing,
Mike

Shadowtski wrote:Sekonic makes good stuff.
I have an L308 that's 20 - 25 years old.
Still looks and works like brand new.

Good growing,
Mike

Yeah, I've had this one for over 10 years... I don't remember anymore. Its an L-385. I am a photographer by profession, so it gets very very well used.