Does glass block light?

HydroChron

HydroChron

Well-Known Member
I am using a air cooled hood that has safety glass. I have read that the glass diminishes the light and takes away UVA. I am wondering if anyone thinks that it is a really bad idea to use glass and if i would be better off taking the glass out or if it is not that big of a difference. I have heard both sides but one thing i am noticing now is that the nicer grows that i see never have glass between there lights and plants. I would love to settle this once and for all so PLEASE put in some input and let me know what the true pros out there think!! thanks for your time!
 
D

Dutch1976

Well-Known Member
In one of my "Ask Ed" books he says not to use the glass unless heat is a problem and you are venting out the top of the lamp. I bought a 1000w hps and never used the glass. (the fuses kept blowing in the lamp, fuck digital lamps, unless technology has gotten better)
 
bl33b

bl33b

Well-Known Member
dunno if it blocks any light, but with a homemade cool tube I am able to get the light much closer to my plants than without it. Also, I am able to keep temps down 5-7 degrees F with the tube. I made the cool tube half way thru my first grow so I dont have any thing to compare personally.
 
normlpothead

normlpothead

Well-Known Member
The amount of light blocked is insignificant compared to the heat savings of having a vented hood, or having a red hot bulb explode over you ladies. I'm pretty sure it's a safety issue.
 
kirby

kirby

Well-Known Member
Glass blocks UV(B) light, and the amount of UVB light your plant receives during flowering will have an impact on the resin and THC production. Outdoor plants get more UV light from the sun, so usually they're more potent or resinous... A lot of people will take the glass off their lights when they receive it.. the main reason for that glass is to block harmful UV rays
 
HydroChron

HydroChron

Well-Known Member
bl33b said:
dunno if it blocks any light, but with a homemade cool tube I am able to get the light much closer to my plants than without it. Also, I am able to keep temps down 5-7 degrees F with the tube. I made the cool tube half way thru my first grow so I dont have any thing to compare personally.
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i think your right BL33B. I was having a huge heat issue due to a HPS in a small area and now that i have the glass i can get much much closer then i wold be able to woithout it. soo am I gaining light by being able to get it closer or am i losing light by have the glass. Im not sure which is worth it. Will there be a noticable difference in trichome production if i remove the glass or will i lose production because i will be forced to move the light further away. Its the never ending question that will just kep on circling around. Thanks for everyone thoughts though and please keep them coming! --Thanks
 
massmurda420

massmurda420

Well-Known Member
It could I'm shure, but i dont think light companys would put a light blocker over their lights
thinks about this for a few hours then get back to me Otay?
 
ceestyle

ceestyle

Well-Known Member
Glass blocks much UV light. The effect of this is debatable.

Personally, I think the heat control is worth it.
 
ceestyle

ceestyle

Well-Known Member
massmurda420 said:
It could I'm shure, but i dont think light companys would put a light blocker over their lights
thinks about this for a few hours then get back to me Otay?
Click to expand...
Hey man. Why exactly is your nickname "massmurda"? And what does "massmurda" have to do with "420", smoking, or growing weed?
 
massmurda420

massmurda420

Well-Known Member
ceestyle said:
Hey man. Why exactly is your nickname "massmurda"? And what does "massmurda" have to do with "420", smoking, or growing weed?
Click to expand...
420 has to do with weed smoking of the dope
and massmurda is wut i do
lol nah its insaneclownposse its a hot acc name as well
i use it for any acc i got
yea wtf does ceestyle mean huh huh huh huh huh????????????
 
ceestyle

ceestyle

Well-Known Member
man, since when does asking what someone's nick means invoke such a nasty response? you guys need to smoke some weed ... or put the word "douche" in your nicks.

for the love of god ...

ceestyle was a nick given to me by a friend of mine more than a decade ago. 'cee' is my first initial. the second half is, well, like an apt nickname, like D-funk, or B Real, something like that. It's also a double entendre.
 
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meathook666

meathook666

Well-Known Member
massmurda420 said:
420 has to do with weed smoking of the dope
and massmurda is wut i do
lol nah its insaneclownposse its a hot acc name as well
i use it for any acc i got
yea wtf does ceestyle mean huh huh huh huh huh????????????
Click to expand...
just curious...does acc mean association of christian counsellors?
 
thelastpirate

thelastpirate

Well-Known Member
Clear glass in and of itself is "neutral density". It blocks light equally across the spectrum. Depending on the quality of glass, this light blockage can be as much as 30%. Auto glass (your car windows) tests at 70% visible light transmission, meaning it blocks 30% of the light passing thru it. I would assume that a "protective" piece of glass for an HID fixture will be tempered, and right at that 70% visible light transmission. The benefit of being able to get the lamp closer to the plants will MORE than offset any loss of light.
 
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