UV coated flashtube or non UV?

[photop]

Is there any benefit to one of these for my photogenic powerlights when doing yearbook pictures? I will be bouncing them out of white or silver lined umbrellas.

 

[Derrel]

I HAVE a mix of UV-coated and non-coated tubes, and have mostly used non-coated tubes since 1986...I started with UV coated tubes in 2007...I set my final WB and tint based on appearance in Lightroom.. IF you _have_ coated tubes, feel free to use them.

SOME people swear by mixing non-coated and coated tubes: as I recall, it's non-coated tubes on backgrounds, coated on people in the foreground...

 

[tirediron]

I too have a mix; a while ago I spent a couple of hours in the studio comparing UV and non-UV; I found the difference to be so slight that I don't even think about it any more.

 

[photop]

Thanks all! Then I will stick with the non coated as there is a bit of a price difference.

 

[JBPhotog]

Hang on a mo! Do you shoot fabrics or people wearing clothes?

Although digital sensors are not afflicted by UV like film was, thus the existence of UV filters "back in the day", they can be influenced by fluorescence. This occurs when the light source emits high UV and fabric brighteners and dyes can fluoresce making nearly impossible to represent the actual colour of the subject. Kodak published a white paper on this many years ago and I have witnessed this on occasion when working with uncoated flash tubes. All of my strobes are UV coated and if you have the option it is best to keep them all the same for consistency.

 

[Derrel]

How much of a price difference are we talking about here? Is $10 or $30 difference per tube? Keep in mind that a good flash tube for a high-quality Flash unit will probably last 20 to 40 years. I still have two of three Speedotron m11-style tubes from 1986 in operation, so that gives 33 years. The other tube from the original three was broken when the light stand tipped over and the lamp hit directly on the concrete floor.

As far as fabrics go, it has been my experience that certain shades of purple and certain shades of white can be tricky to record . I have read many times before that phosphorescent brighteners in white
fabrics are the cause of why sometimes something that is supposed to be pure white is rendered as less than pure white,with sometimes a slight bit of bluishness.

I was already under the impression that you already own flash tubes for your light units. If you do not have any flash tubes, I don't see why you don't spend the money and get the UV coated tubes and be done for once and for all

 

[JBPhotog]

I have witnessed neon glow from fabrics that to the eye looked normal, all generated by the UV spectrum from the flash tube.

If you are buying replacement tubes or new flash heads, the cost difference will pencil out to fractions of a penny over the life of the tube.

 

[photop]

Hmmmmm..... y’all are a wealth of information! Well ok then. I’m shooting a few hundred university students against a light grey backdrop for the yearbook. So of course lots of colors. I’ve had these lights and bulbs about 20 yrs now but I hardly use them. Since I’m mostly outside. One bulb is uncoated and the other is coated. The original broke pretty quickly and when ordered another online I got the coated. (I actually called the company to see why it was discolored). Anyway, I’ve used them together very few times. This is the biggest studio type job I’ve ever had coming up so just want to be prepared and have extra everything on hand, including bulbs. There will 2 set ups, 2 photographers, one power light for each setup.

 

[JBPhotog]

If you have some lead time, you could also try a UV gel. Rosco make a Cinegel R3114 which absorbs UV which may be enough, but for consistency, I'd recommend UV coated tubes.