View Full Version : Coated Filter on Uncoated lens=Coated?

5-Feb-2010, 23:42
Hello, I am a beginner at LF photography, just received a wista field camera and started to assemble a LF kit, still finding my way and learning at the moment.

While surfing the market for lens, I came across many bargain lens, mostly uncoated. Experience told me lens coating reduce internal light reflection, lens flare, and increase contrast, more favorable for color than B/W (I do both). Lens with coating is definitely a plus (on the price as well!) but not essential.

However, I wonder will a coated UV filter like B+W MRC filter over the uncoated lens give the same effect as a coated lens?

Lucas Kao

Jack Dahlgren
6-Feb-2010, 00:07
No, the lens coating minimizes internal reflections so your filter will do nothing - in fact it will just add another reflective surface so will make things worse.

Steve Hamley
7-Feb-2010, 10:41
Jack's right. You should be looking at adding a good lens hood, preferably a compendium if you're really serious. A good lens hood will get you a lot closer to coated lens performance.

Cheers, Steve

Arne Croell
7-Feb-2010, 11:02
What Jack and Steve said.

Each uncoated air-glass interface reflects at least 4% of the light, a single coated one about 1%, and multicoated somewhere below 1%. So for a 4-group lens = 8 surfaces about 28% gets reflected [1-0.96^8=0.2786]. If you add a single coated filter it is slightly over 29% [1-(0.96^8)*(0.99^2)=0.293].

7-Feb-2010, 23:34
Thanks guys for the answer, I will be looking for a good lens hood now! :)