Question about black light blue flourescent tubes?

[jesse7392]

Okay I have a rather odd question and am not sure whether its something to be concerned with or not.
For a couple years now I've been using a bank of (8) 48" 40Watt T12 Flourescent Black Light Blue bulbs in a homemade UV box for my alt process printing.
Last night I had two bulbs go out on me. I found a place locally that sells them, so I bought some replacements.
The question I have is that apparently BLB bulbs come mostly in the T10 diameter as opposed to the T12 diameter.
They are still 40watt bulbs and BLB, but I'm wondering if the UV output will differ greatly if I replace the two burned out bulbs with 2 of the T10 bulbs.
Basically having a bank of 8 bulbs where 6 are T12 and 2 are T10. My thought is to put the T10 bulbs on the outside edges of the full 8 bank of bulbs.
Apparently most manufacturers are going to the T10 diameter because its more efficient and they still work in the same ballasts/fixtures as T12 bulbs.

May not be a big deal and the smaller T10 diameter might just make it easier to put the bulbs in

 

[Rick A]

It shouldn't be a deal at all, 4o watts is 40 watts regardless of tube diameter. However, spacing may become an issue with a slightly wider gap between them, it may cause banding on the print. All you can do is test it, maybe use the new tubes one on each end of your setup.

 

[Ian Leake]

I have found that tubes from different manufacturers may have different UV output, even though they have the same nominal wattage. The wattage refers to the input power consumption not the UV intensity. As you have 2 replacements in a bank of 8, I would place these on the outer sides where they will least impact on printing.

 

[jesse7392]

It shouldn't be a deal at all, 4o watts is 40 watts regardless of tube diameter. However, spacing may become an issue with a slightly wider gap between them, it may cause banding on the print. All you can do is test it, maybe use the new tubes one on each end of your setup.

Thanks for the tips

 

[koraks]

I have found that tubes from different manufacturers may have different UV output, even though they have the same nominal wattage.

Yes, and furthermore, aging will alter light output.

I agree with the others - put the new tubes at the extremes of the array.

 

[MattKing]

I wonder if the result of that choice will be more density at the sides of your prints.
I guess it will depend on your box.