Difference between Lee No.15 and No.16

[Songyun]

I have two lee filters. when I bought it, the seller claimed they are both orange filter. But one of them has No.15 on it the other one is No.16. I checked robert white's website, it shows No.15 is yellow (darker) No. 16 is yellow orange. But when I have two filter side by side, I can not tell the difference. Is that because the two color are really close, or it might be marked wrong?

[Ron Marshall]

I have two lee filters. when I bought it, the seller claimed they are both orange filter. But one of them has No.15 on it the other one is No.16. I checked robert white's website, it shows No.15 is yellow (darker) No. 16 is yellow orange. But when I have two filter side by side, I can not tell the difference. Is that because the two color are really close, or it might be marked wrong?

If those designations are Wratten # then they are very close; no need for both.

I have #12 and #16 and they are very close, but easy to tell apart.

The following chart doesn't have a #16, but it gives you an idea how close some of the filters are in absorption spectra. The colours displayed for the various filters are not accurate, but the cutoff wavelengths are:

http://photo.net/learn/optics/edscott/cf000010

[Songyun]

Thanks, Ron.

[Helen Bach]

As Ron says, the Wratten 15 and 16 are very close. The 15 has a transmittance of 50% at just under 530 nm and for the 16 it is at just over 540 nm.

Best,
Helen