SB800 Observation

[ranchjp]

I've used a Nikon amber gel on an SB800 for quite a few shots (100?). I've noticed that the plastic fresnel now has an amber stripe on it now. Presumably the brightness of the strobe vaporizes a bit of the gell, which subsequently exchanges to the plastic?
Jerry

[Nikonfreak]

Actually, it's more like the heat of the strobe firing melts the color off the gel and onto the plastic.

It's discharge is hot enough to burn when the flash fires.

[ranchjp]

Wow
I didn't realize they got that hot
Jerry

[gpf]

Originally Posted by ranchjp

Wow
I didn't realize they got that hot
Jerry

See page 96 of the manual: "Notes on using colored gel filters".

Even warns you not to use gels with repeating flash because of the high temperature.

[ranchjp]

Yep
I did read that once before and now I recall. I was just surprised by the transfer to the fresnel. Isn't physics wonderful ?
Jerry

[sgjimmy]

for those who regularly or in a quick fix use tissue paper to diffuse flash be it hammerhead, hot shoe or pop up, i'd be careful not to let the tissue touch the flash fresnel lens. you will smell a burning smell in a short while if you fire repeatedly.

learned from a long ago experience.

[ranchjp]

Yep, I see what it says in the manual, and I understand, but it truly is impressive the heat that can be generated from 4 AA cells, and capacitor(s), and discharge circuits. Clearly because all that energy is released in < 1/1000 second..Jerry

[LNL Photo]

You also need to be careful with how fast you fire with the batteries. Firing too fast will heat the batteries up and eventually burn out the flash at a cost of $109 plus tax and shipping. LOL.

You can try an experiment fire repeatedly a bunch of times and pop out the batteries and touch them.

Take care, Larz

[Nikonfreak]

Hehe... I'd also not encourage one to try a white sheet as a makeshift diffuser panel in front of hot lights. Learned that one by experience too... and how to use a fire extinguisher.



Julio