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by DChan on Tue Dec 12, 2017 1:18 am
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Just received my Breakthrough filters tonight and took a couple of test shots with the X4 6 stop circular ND filter and here's what I found:


Full shot:
Image
100% cropped:
Image
Photo taken hand-held using Olympus EM-1 Mk 2 with 12-40 f2.8. ISO 400, f2.8 1/20 sec. No post-processing just cropped and resized for posting purpose. Photo shown is under-exposed by one stop using camera suggested exposure settings in aperture-priority mode with the 6-stop filter attached. I took a couple more shots pointing the camera away from the light source and found those "rings" are in each of them. They're more noticeable when the shots are under-exposed.

I'm wondering what could have caused those rings.
 

by E.J. Peiker on Tue Dec 12, 2017 7:46 am
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The light is AC at 50 or 60Hz (depending on where in the world you took the shot) so it is basically a sine wave so you recorded 3 cycles which likely set up that pattern. Slow the shutter speed and it will reduce or shoot it at at least 1/60 and have the camera's AC flicker detection set to on (assuming it has such a setting) and the camera will time it's exposure to prevent shooting during an off cycle.
 

by Dave Kocher on Tue Dec 12, 2017 1:53 pm
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Interesting. My first thought was Newton's Rings.
Not familiar with the flicker explanation.  Can you explain just how flicker can produce the rings, E.J.?
DChan, when the camera was pointed away from the lamp, are you saying the rings still appeared in the same place on the lamp, or were they in the same place in the frame?
Are the rings visible to the eye when looking at the lamp?
For Newton's rings to form with continuous spectrum white light, there must be two pieces of glass or whatever (almost) in contact because the coherence length is so short.  But for the new semiconductor lamps, the coherence length might be longer, don't really know.  Do you know what kind of bulb is in the lamp?
Just some ideas...
 

by E.J. Peiker on Tue Dec 12, 2017 2:27 pm
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Dave, your explanation sounds plausible. I was thinking the rings were due to the lamp being lit by a filament in the center of the bulb.
 

by Scott B on Tue Dec 12, 2017 7:38 pm
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Interesting the rings are centered dead center on the full shot. That would lead me to believe that the rings are created by the camera or filter not the light.
 

by DChan on Wed Dec 13, 2017 1:57 am
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Thank you for the responses guys !

That ceiling light has three 23 W energy saving twisted compact fluorescent bulbs inside. The camera itself has no A-A filter if that means anything.

As pointed out by Scott B, the rings appear in the center of the shot. At this point, I'm blaming the filter. The reason being I can see the rings with my naked eyes by holding the filter up to the light at certain angles. Take a look at the shots below.

full shot
Image
cropped:
Image
Full shot with another light:
Image
cropped:
Image
Ceiling light between me and the folded boxes and you can still see the ring in the centre of the photo:
Image


No 6 stop filter attached, flicker reduction set to either auto or 60 hz. No rings. Full shot
Image
Cropped. No rings. So, not my camera's fault :-)
Image
Another fluorescent light found somewhere else. With filter. The rings are there:
Image
There're no rings when pointed at LED light. I also went out taking photos here and there in town today with the filter on and I don't notice any rings except when pointing my camera at fluorescent lights.

So far, I guess it's the coating on the filter and the fluorescent lights. If you have filters from Breakthrough, may be you can try it with yours and see you get the same results.
 

by John Labrenz on Wed Dec 13, 2017 2:55 am
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What you are seeing is "Newton's Rings"
I have encountered the same effect while taking Aurora photos.

Do a quick Google search for Newton's rings & Aurora...you will see the same effect you have produced here.
As the light produced from the flourescent fixture is quite similar to that produced by the Aurora, you are seeing them when pointed at that light source.
To avoid them...remove the filter when photographing similar wavelength light sources.
 

by E.J. Peiker on Wed Dec 13, 2017 7:50 am
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Very interesting and great sleuthing.  I just put this to the test in my laundry room with a fluorescent light.  I also happen to have 5/6 stop filters from Breakthrough, Lee, Heliopan, B&W, Hoya, Singh-Ray, and Tiffen.  The only one that has these rings is the Breakthrough Filters one.  That said, in outdoor situations I still opt for the Breakthrough as they impart the least amount of color in long exposures.  I have an article on this with comparisons in my next newsletter due out early next week.
 

by John Labrenz on Wed Dec 13, 2017 8:28 pm
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Green Aurora emissions occur at a wavelength of 558 nanometers.
Interestingly, a typical cool white flourescent lighting fixture emits two spikes...one at about 540 nanometers, the other at about 615 nanometers.

EJ; can you try your test using a normal UV or "skylight" filter made by the different manufacturers. I'd be curious to see the results.
 

by E.J. Peiker on Wed Dec 13, 2017 11:22 pm
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John Labrenz wrote:Green Aurora emissions occur at a wavelength of 558 nanometers.
Interestingly, a typical cool white flourescent lighting fixture emits two spikes...one at about 540 nanometers, the other at about 615 nanometers.

EJ; can you try your test using a normal UV or "skylight" filter made by the different manufacturers.  I'd be curious to see the results.
I don't own any UV or Skylight filters, sorry!
 

by DChan on Thu Dec 14, 2017 9:23 am
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E.J. Peiker wrote:... I just put this to the test in my laundry room with a fluorescent light.  I also happen to have 5/6 stop filters from Breakthrough, Lee, Heliopan, B&W, Hoya, Singh-Ray, and Tiffen.  The only one that has these rings is the Breakthrough Filters one. ...
Question then is: is it a defect of Breakthrough's filters??
 

by E.J. Peiker on Thu Dec 14, 2017 10:08 am
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DChan wrote:
E.J. Peiker wrote:... I just put this to the test in my laundry room with a fluorescent light.  I also happen to have 5/6 stop filters from Breakthrough, Lee, Heliopan, B&W, Hoya, Singh-Ray, and Tiffen.  The only one that has these rings is the Breakthrough Filters one. ...
Question then is: is it a defect of Breakthrough's filters??
Not at all, IMHO - these are primarily designed for and marketed for daylight use to reduce shutter speed.  The only conditions you would see this is when shooting a fluorescent light as in the example.  The fact that they impart much less color cast than many of the others is way more of a benefit than Newton rings when shooting fluorescent bulbs - at least for nature photographers.  Not sure why you would use one shooting fluorescent lighting fixtures, and if so, then these aren't the filters for you but for the rest of us, the lack of a color cast is wau more important.

Here's an excerpt from my next newsletter comparing 10 stop filters:
Image
 

by Justin C on Thu Dec 14, 2017 2:06 pm
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The loss of sharpness when using the Cokin filter is severe, even on these small jpegs. Certainly one to avoid IMO.
Justin
 

by DChan on Thu Dec 14, 2017 3:10 pm
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Here's another company that supposedly make quality filters. Well, at least it seems to be using the same type of glass that Breakthrough uses for its X4 filters:

http://www.winecountry.camera/

I watched a video last night and its filter holder looks pretty good.
 

by Scott B on Thu Dec 14, 2017 4:43 pm
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E.J. That is an incredible visual. The bottom row does a great job of capturing the color in the filter the colored tiles mask it to some degree but it is still noticeable.. I would have to say the Newton rings are a weakness of the breakthrough filter but not a defect. I tried to think of all the times I have used neutral density filters and I can't think of one that had an artificial light or an aurora in it. That is a weakness I would live with. And based on my budget I will need to live with my filters but if I were shopping the breakthrough filter would be high on my list.
 

by E.J. Peiker on Thu Dec 14, 2017 7:20 pm
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Justin C wrote:The loss of sharpness when using the Cokin filter is severe, even on these small jpegs. Certainly one to avoid IMO.
Yeah I address that in the article.  It was specific to that Cokin.  I have a different one with different thread size that doesn't do that but the color shift is identical.
 

by Mike in O on Fri Dec 15, 2017 10:18 am
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EJ, I am thinking that I would like to get into the great unknown, video. Specifically with the rx10IV, what would you use as neutral density filter to slow shutter down? I guess the earlier models had a ND built in but not so with the IV. That break through sure seems to be the most neutral.
 

by E.J. Peiker on Fri Dec 15, 2017 4:24 pm
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Mike in O wrote:EJ, I am thinking that I would like to get into the great unknown, video.  Specifically with the rx10IV, what would you use as neutral density filter to slow shutter down?  I guess the earlier models had a ND built in but not so with the IV.  That break through sure seems to be the most neutral.
For video, I think getting a 3 stop and a 6 stop should get you through any situation.
 

by Mike in O on Fri Dec 15, 2017 4:42 pm
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Thanks
 

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