Weird green flare in spectacles... anyone seen it before

[markstennett]

<p>I'm sure its a simple answer but twice now I have gotten this green flare when photographing someone with glasses... What makes it weird (to me anyway) is the first time (the corporate guy) was indoors with a mix of speedlights and natural lighting through a window. Almost every shot had it so I figured it was some stray lighting in the room... although there were no flouros which would have been my first guess<br>

Anyway...I just got back from Thailand where I shot this old guy's image outside, no flash, under cover of a veranda and there it was again...similar anyway<br>

Someone posted something similar here about 4 years ago but it was never answered...<br>

Be interested to know if anyone has had this happen..I'm sure I can't be the only one..<br>

Both shot with Canon 5D<br>

corporate guy with 24-105 f4 @ 1/125 f5.6 iso 100 and the old guy with the 70-200 f2.8 @ 1/125 f5.0 iso 200</p>

<p>Cheers<br>

Mark </p>

<p> </p>

[scrivyscriv]

<p>You got any samples to put up?</p>

 

[scott_murphy_photography]

<p>Are you sure his glasses were not multi-coated? That could account for the greenish tint and what you may be construing as flare might just be a broad (non-specular) reflection in the glasses.</p>

[markstennett]

<p>Hi .. you guys too quick.. and I'm too new at this.. here are the images... I couldn't tell you anything about the glasses themself.</p><div></div>

[matthew_newton]

<p>Most modern glasses are coated and I tend to see green type reflections in a number of them (mine have it and are not anti-glate coated). I don't see or do to many pictures of people with glasses though.</p>

[SCL]

<p>Looks like multi-coating on the lenses.</p>

[lex_jenkins]

<p>My coated no-line bifocals do the same thing. I can see multi-colored ghosting flare spots through them when driving at night. It was a little distracting at first but not bad.</p>

[scrivyscriv]

<p>Yeah, probably glare from the coating on the glasses lens.</p>

[markstennett]

<p>

 

<p>Thanks for the quick responses.. <br>

so next question is what can be done.. I didn't get it in every single shot of the corporate guy so I'm assuming you would adjust the angle of the light that strikes the glasses until you don't get it (or take the glasses off I guess ). With the old bloke it was one shot only, then he was gone...</p>

 

 

</p>

[steven_p]

<p>That's glare from "anti reflection" multi-coating. Different brands of coating cast different colors. The last I was in the biz. you could get green, orangeish, or gold.</p>

<p>You will have to change the angle of your lighting source, or possibly use the select tool in your graphics program and change the color cast of the unwanted reflection.</p>

[Alan Marcus]

<p >Lens coating:</p>

<p >In 1892 an optician, Harold Taylor, noted that older lenses transmitted approximately 5% more light energy than newer lenses with the same specifications. Seems older lenses are “bloomed”. Atmospheric pollution, particularly in industrial areas, naturally over-coats glass. This transparent film is often called tarnish. Now the thickness of the over coat is important. Normally light, encountering the polished surface of glass, suffers a loss because about 5% is reflected away due to reflection from the lens’s shinny surface. These reflected rays are lost however if a transparent coating exists on the surface of the lens, the departing rays, hitting the coat-to-air junction forward of the glass, are re-reflected backwards thus they add their energy to the next light wave. The coating is most effective if it is 1/4 wave length.</p>

<p > </p>

<p >Now this small improvement in transmission is seemly inconsequential however in a complex optical system with many elements, the gain can be quit high. More importantly, each lens-to-air junction reflects away some rays. These are misdirected rays that hit the next lens forward. Much of this energy will arrive at the image plane. These misdirected rays are scrambled rays, they bathe the image and produce an effect we call flare. Flare is devastating; it causes a horrific loss in contrast.</p>

<p > </p>

<p >By 1935 the optical industry was artificially ageing lenses by vacuum coating magnesium fluoride or silicon dioxide. Modern lenses are coated with an average of 7 ~ 11 coats of different thicknesses to control various wavelengths. Some specialized optics can sport as many as 25 coats. </p>

<p > </p>

<p >A coated lens still reflects away some light rays. If you see blue, you should know that its complement, yellow (red + green) has improved transmission. If you see green than the coating thickness targets green’s complement which is magenta. Now the lens allows a higher percentage of red + blue to transverse.</p>

<p > </p>

<p >Coatings a single element eyeglass lens is common practice. However, in my option this provides little benefit except it surely lines the pockets of eyeglass makers and dispensers. </p>

[tony_leinster]

<p>Change position slightly or use a polarising filter, although this will lose you a couple of stops. You should be able to handle that with speedlights though.</p>

[rod_sainty2]

<p>I'm surprised that any modern photographer would find the green reflection puzzling, given that our camera lenses are multicoated. In the 1950s and '60s, blue and pale yellow reflections were most common, but with the SMC multicoating introduced by Pentax in 1971 and the similar T* coating introduced later by Zeiss, magenta, crimson, deep green and orange reflections became common, with several colours reflected by different elements within the one lens. Green is a common reflection.</p>

<p>"<em>in my option this provides little benefit except it surely lines the pockets of eyeglass makers and dispensers</em>" I disagree; I've seen a big difference between multicoated and non-coated lenses of my prescription (for myopia). The benefit is of one's appearance to others, not the wearer's vision. In my experience, the multicoating dramatically cuts down the appearance of white "glassiness" to others.</p>

[jnina]

<p>Since you already took the pictures you can retouch them in photoshop with the Stamp Tool. Set opacity to 100% and the flow to 50%. Then set the tool size to a small circle and make a duplicate of the layer before you start retouching. You need to be careful as not to make it to evident that that part was retouch. Also if you have a similar photograph of this person and with the face in the same angle and no flare you can copy the lens part and paste to the other picture. There is a article on how to this at :<br>

<a href="http://www.thinkcamera.com/news/article/mps/uan/735">http://www.thinkcamera.com/news/article/mps/uan/735</a> and <a href="http://www.thinkcamera.com/news/article/mps/uan/719">http://www.thinkcamera.com/news/article/mps/uan/719</a><br>

Hope this helped!</p>

[garypeck]

<p>You'll have to isolate the green areas in photoshop - convert or desaturate to allow you to plug in a skin tone. Then adjust density to match - might be easier with a rubber stamp tool.<br>

gary</p>

[markstennett]

<p>Thanks again everyone for taking the time.... for me, everything is puzzling when you see it for the first time.. that's what makes these forums so great... <br>

cheers<br>

Mark</p>