Leica KAF-18500 CCD used in the M9 and M Monochrom is discontinued, Sensor replacement no longer possible

TraamisVOS

Hall of Famer
Nov 29, 2010
Melbourne, Australia
Hello, I saw this and registered just to reply. I am technician in Portland Oregon I’m actually working on a way to replace the cover glass with a glass that I believe is what was used on the “new sensors” just trying to find a good way on removing the original cover glass in a more efficient way...
Apologies if I'm a little slow on the uptake but are you saying you're able to 'fix' the corroded CCD sensors in the M9s?
 

BrianS

Legend
Jul 7, 2010

I see that Advance Camera in Portland, OR offers an IR conversion for cameras. The S8612 is cemented in place on the KAF-18500, I'll be very interested if it can be replaced. Back in 2009 I called Kodak and asked if they could do a full-spectrum/Monochrome version of the M9. At least they did a Monochrome version. The engineer at Kodak told me that they had wanted to do a Monochrome version of the M8 when it first came out. I still have the very first full-spectrum camera sold by Kodak, DCS200ir.
 

Jadon.Rosado

Regular
Sep 11, 2020

I see that Advance Camera in Portland, OR offers an IR conversion for cameras. The S8612 is cemented in place on the KAF-18500, I'll be very interested if it can be replaced. Back in 2009 I called Kodak and asked if they could do a full-spectrum/Monochrome version of the M9. At least they did a Monochrome version. The engineer at Kodak told me that they had wanted to do a Monochrome version of the M8 when it first came out. I still have the very first full-spectrum camera sold by Kodak, DCS200ir.
I know, I’m their Leica tech. I have the old filter removed and I have the replacement glass on the way. Unfortunately kolari vision beat me to it this afternoon. I had high hopes of being the first person to pick up the torch but most of R&D has been on my own time with limited resources I suppose second place will have to do...
 

Jadon.Rosado

Regular
Sep 11, 2020
I know, I’m their Leica tech. I have the old filter removed and I have the replacement glass on the way. Unfortunately kolari vision beat me to it this afternoon. I had high hopes of being the first person to pick up the torch but most of R&D has been on my own time with limited resources I suppose second place will have to do...
Sorry to double reply... kinda new to forums. This is what o currently have apart. As stated before I have the replacement glass on the way, near identical refractive indexes so white balance shouldn’t be an issue.
 

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Jadon.Rosado

Regular
Sep 11, 2020
Maybe Jason can contact Leica rumors to post there also for exposure... I saw the Kolari ccd repair in Leicarumors:
Kolari Vision is now repairing corroded Leica M9 CCD sensors for $1,000 - Leica Rumors
yeah they announced this just a day after I made my first post, what a coincidence! I’m still working out a few kinks in the process (mostly the do’s and donts of handling a raw ccd) the new glass should be here next week so I’ll certainly report my findings and then reach out to leica rumors. $1000 is still nearly half the value of the M9, my initial thoughts were about $700 for the replacement. It takes a lot of work to remove the filter but I want to make this a more realistic option for M9 owner
 

BrianS

Legend
Jul 7, 2010
Maybe Jason can contact Leica rumors to post there also for exposure... I saw the Kolari ccd repair in Leicarumors:
Kolari Vision is now repairing corroded Leica M9 CCD sensors for $1,000 - Leica Rumors

Also, Leica M9 Sensor 'Corrosion' Due to Dumb Design Decision, Report Claims
The IR absorbing glass used for the M8 does not corrode. It also has a 5% transmission in IR.
Schott S8612 glass was used in the original M9 sensor, not a BG glass. The S8612 transmits about 0.1% in the IR, and has higher transmission in visible than other IR absorbing glass. From an optical point of view, it is optimal for the intended function. Kodak thought that the coating would sufficiently rpotect the glass from humidity. They were wrong, it happens. My M9 went 7 years before the first sings of corrosion appeared. I had the sensor replaced at the very first sign or a problem.
 

Jadon.Rosado

Regular
Sep 11, 2020
The IR absorbing glass used for the M8 does not corrode. It also has a 5% transmission in IR.
Schott S8612 glass was used in the original M9 sensor, not a BG glass. The S8612 transmits about 0.1% in the IR, and has higher transmission in visible than other IR absorbing glass. From an optical point of view, it is optimal for the intended function. Kodak thought that the coating would sufficiently rpotect the glass from humidity. They were wrong, it happens. My M9 went 7 years before the first sings of corrosion appeared. I had the sensor replaced at the very first sign or a problem.
I spent quite a bit of time looking at charts and asking around different glass suppliers and the closest glass to the schott s8612 is the schott BG40. That’s what I’ll be using. The BG38 and 55 may work but the ref reactive indexes are different leading to a loss in light transmission. Leica has to reflash the firmware to compensate for the change in sensitivity. In theory the BG40 is the closest to the s8612 without compromising the IQ as well as changing the thickness of the glass. Using thicker glass will lead to a focus shift. I’m hoping that the method I’m using will be the least invasive and simply be a replacement rather than a modification as I’d like to preserve the look and specifications as much as i can.
 

BrianS

Legend
Jul 7, 2010


When the problem was first announced, before the new sensor was available- I looked at a number of different Schott data sheets as well. I remember BG40 and some others. The BG55 looked like the same index of refraction, the data sheet has more precision than the S8612 sheet.


I also remember that BG55 was "re-released" around the time of the new sensor.

If I'm right about the "mystery part number" found on the ONSEMI web site, BG55 was used for the replacement and the color dye was also changed.
" kaf-18500-fxa-jh-aa-bg55 "- no one else has references to this part number. DigiKey used to sell the original KAF-18500 with S8612 glass as found on the M9. They never sold the replacement.

Looking at the transmission curves of the S8612 vs BG55, it's easy to see why Kodak engineers wanted to use it. The glass is typically used in a sandwiched stack, glass used to protect it from humidity. The geometry of the M-Mount prevented that arrangement. They thought coating it would be enough protection, they were wrong. I've had some optical engineers working for me- years ago. Several times had to point out that some really cool optical designs were not viable.

(found the discussion from over 5 years ago:

BG-18 looked like the same refractive index, and did not have the warning for corrosion. BG55 was re-introduced to the market areoind the time of the discussion.
I was posting as "Lenshacker". for obvious reasons...)
 
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TraamisVOS

Hall of Famer
Nov 29, 2010
Melbourne, Australia
Yes you got that right
I've been seeing some news pop up in my social media about repairing the M9s, is that you?

I have an M9-P which hasn't corroded yet but I was really disappointed when Leica announced they were going to end their sensor replacement program. I'm a lot happier knowing that it will remain fixable whenever it starts to corrode.
 
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rayvonn

Hall of Famer
Jan 19, 2015
I've been seeing some news pop up in my social media about repairing the M9s, is that you?

I have an M9-P which hasn't corroded yet but I was really disappointed when Leica announced they weren't going to end their sensor replacement program. I'm a lot happier knowing that it will be remain fixable whenever it starts to corrode.
You can say that again!
 

BrianS

Legend
Jul 7, 2010
My oldest working Digital camera is from 1992.
It cost $4000 more than a standard DCS200 to have made with clear cover glass, $12,400 for the body. 1992 dollars. Kodak made it for me. The sensors I worked on before it were really expensive.

So $1000 in the year 2020 to have a new cover glass put on an M9 and M Monochrom seems like a deal.
 

BrianS

Legend
Jul 7, 2010
That sounds nuts! Even the M10 today is cheaper than that.



What exactly do you mean by that? Custom/bespoke?
I called up the Kodak Sensor Division, spoke with the engineers, and told them I wanted a Kodak DCS200 with a clear cover glass. I looked at the data sheet for the KAF-1600 and noted it was sensitive in the IR region, out to 1.1uM. I wanted the full spectral response for the camera. The engineer laughed, told me I wanted them to undo years of work to make digital sensors look like film. They called a few weeks later, told me they were going to do a special run of 50 CCD's with the cover glass I wanted, an extra $4K each. I have the very first one.

In 2009 I called the same group and asked how much a monochrome version of the KAF-18500 would cost. We had a great conversation, he remembered me from years before.
 

BrianS

Legend
Jul 7, 2010
What was the story there? Why a special run, what did they do with the 49 remaining glass?
I was the first person to call Kodak and ask for an Infrared (actually full-spectrum) version of the camera. I worked with infrared sensors since 1981, so more than 10 years at the time I called. When Kodak called back, they told me after I called that the Army Night Vision labs also called them and asked for the same thing. Kodak realized that an IR version of the camera was a viable product. I got the first one- being the first to ask for it.

All these years later- IR and Full spectrum cameras are still "a thing", with conversions being offered by a few specialty shops like Jadon's.
THANKYOU FOR THIS SERVICE!

I have a full-spectrum Olympus EP2. And still have the Kodak DCS200ir. Some years ago I purchased a "Sensors Unlimited" near-IR camera, sensitive past 1.5uM. It used C-Mount. My optical engineer was disappointed with the lens on it, I loaned him my Canon 50/0.95 with the C-Mount adapter on it. Greatly improved the performance.
 

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