Amazing New AR Coated IR Filters from KolariVision.com


Kolari Vision introduces a NEW Anti Reflective IR coating for their conversion filters!

Fuji X100s, 850nm Kolari AR conversion - Under Foley Pier

Fuji X100s, 850nm Kolari AR conversion – Under Foley Pier

I LOVE shooting IR and have a long history with it in both Film and Digital.   I have had over 25 conversions from ALL of the big conversion companies around the country!   But, once in a while I would get a camera that no mater how hard I tried, I will get a hot spot with it or the lenses I used.   You learn how to deal with this by selective use of the aperture but once in a while you would just not be able to get around the problem and loose the shot….  

Fuji X100s, 850nm Kolari AR conversion - Shrimp Boat

Fuji X100s, 850nm Kolari AR conversion – Shrimp Boat

Well about 3 weeks ago Ilija from Kolari (http://www.kolarivision.com ) sent me a note telling me about a new coating process for his conversion filters.   I have a long history with Kolari, LDP and Lifepixel but I have never heard of this till now.  Ilija offered to do a free conversion with this newl IR AR coating for me in return for evaluating it in the real shooting world! So I told him that I would send the X100s off as a test camera and that I needed it back fast in order to allow others to play with the camera also!   Off it went on Tuesday.  Imagine my surprise when I got it back in hand the following Wednesday!

Here is what Kolari says about this new AR IR coating:

  • Uncoated glass has a reflection of around 4-5% at all wavelengths, and we found that this reflection off the sensor filter was bouncing off the glass and reflecting back from the lens housing and aperture blades to cause the hotspots.  We developed this anti-reflective coating that is centered around the IR wavelengths that cause hotspots, and reduced the 5% reflection down to <0.5% (see the attached graph for reflection % by wavelength scan, and the picture of the IR filters for the visual difference of IR reflection).
Unknown

  • The coating does not reduce visible light reflections as much, and does not reduce blue reflections at all. This gives the glass we use a blue shine, since that is the only range that is fully reflected still (see picture of black filters). 
AR coating test on Visible Light

AR coating test on Visible Light

AR coating tests on BLUE light

AR coating tests on BLUE light

  • I am getting ready with a new website which I hope to launch in 1-2 weeks, so I have not put the coated version of the conversions online yet, but they will be offered on our Full spectrum, two spectrum, 590, 665, 720, 850, and Blue IR/NDVI conversions. There will be a $50 optional upgrade on all of our conversions at this point.

 

  • I plan on offering only the coated version eventually, but the batch runs are expensive and I cannot coat our full inventory at once. I’m not sure if you are aware, but we stock custom made custom thickness filters for all our camera/filter combinations so that each conversion gets a piece of glass that maintains the original optical distance (refractive index x physical thickness) as closely as possible, which changes for each filter material. Other companies use a few general size pieces of glass, glue them directly to each sensor, and calibrate the focus for an arbitrary lens, which reduces what they have in inventory. Our design choice means that we have around 200 unique pieces of glass in inventory for DSLR and mirrorless cameras, and another 200 for point and shoot models, so you can imagine the challenge in getting them all coated. – Ilija

Fuji X100s, 850nm Kolari AR conversion - Thru The Door

Fuji X100s, 850nm Kolari AR conversion – Thru The Door

So as you can see they are up and almost ready to start filling orders for these new filters.   

Fuji X100s, 850nm Kolari AR conversion - McClellanville Fleet

Fuji X100s, 850nm Kolari AR conversion – McClellanville Fleet

I have to tell you that with my test conversion on the Fuji X100s to AR 850nm that ALL of my hot spot issues simply went away.  This camera has always had a tendency for IR hot spots.   I have converted, tried and sold so many IR systems in the past that I have lost count.  I could not, would not sell this one as it is one of my most prized IR systems.  To say that I am pleased with the results of the Kolari IR AR Coating is the understatement of the year!

Remember, if you decide to order from Kolari, give them my name for a $15 discount!

 

Advertisements

17 comments on “Amazing New AR Coated IR Filters from KolariVision.com

  1. very interesting. So, does this mean the original infrared blocking filters that are in all cameras have a similar coating? I’m wondering about this since the cameras/lenses don’t hot spot until they’ve been converted and that glass is replaced. Also, is this a similar coating to what goes on the outside of lenses? So, what Ilija and you are saying is a lens that used to hotspot in infrared at say any stop beyond f8 will now be good. Is that correct?

    • Not at all. The chances of a hot spot are greatly reduced. There are no coatings like this on normal cameras and lenses because the hot mirror blocked all ir even hot spots and only allowed visible to pass. With an ir conversion all sort on new players are affecting your image like lens coatings and Barrell paints, things that never affected color.

      • Ah, I see. Well it is all fascinating. I wish Ilija had created this coating before I did my most recent conversion there a year or so ago. Every one of my lenses behaves differently. It’d be nice to have uniformity. Well, there’s always the next one.

  2. Mark, great post. This got me thinking about converting an X-Pro2 to IR. I do a lot of street stuff and have had this idea of using IR at night on the street. With that in mind, you know of anyone making an IR flash? I know I could just filter a normal flash but I would think it still would make some visible light. Thanks

  3. Mark, this is exciting news. I see it as a goundbreaker for the IR community. Potential to open up an entire suite of previously unusable lenses is or will be revolutionary. I can’t help but question image quality, however. Is there any degradation, even at close pixel-peeking level noted with the coating?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s