Something funky going on here... (sensor artifacts on P65+ ?)

[Paul2660]

Calibration file?
I guess you don't mean the LCC file?

I doubt I'm able to redo the sensor calibration data, that's not something I would feel comfortable to do and I wouldn't even know how to.

Each Phase back, has a unique calibration file that works to help remove things like tiling, but can also help take out other abnormalities.   On the IQ backs, I know the dealer can help with replacing the file, not sure if this can be done with the P+ backs.  But from looking at the issue, I don't feel this will help. 

As Jeffery said, something has gotten under the IR filter that sits on top of the actual sensor and has dried, leaving the crystal like formations. 

Phase can remove/replace that filter and clean the actual sensor, and the back should be good as new.  Might be a good time to have the back serviced anyway as Phase can run several different checks on the the sensor as they clean it.

Paul C

[Christoph B.]

Yeah I guess that's the way to go - and I'm just glad the back still works and looks like it's something that's fixable!

Good thing I'm currently selling the rest of my analog stuff, that might actually pay for the CLA

[Bart_van_der_Wolf]

So I just noticed something weird. Something that's not really visible under normal conditions and has never shown up until I 'tortured' my raw files in CaptureOne.

Those strange pentagonal shapes show up on my P65+ sensor (always on the same spot) but the sensor itself shows no signs of damage and works without any problems what so ever.

They are not related to the lenses I use, they are the same every time, at every aperture setting and exposure.

Hi,

If the patterns do not change (get sharper or blurrier) when you change the aperture, then it must be something in the sensor, and requires a service calibration. If there is a difference in sharpness when you vary the aperture, then it is something in front of the sensor itself, casting a sort of shadow (sharper with narrower apertures).

From your description it seems to be sensor calibration related and not something that cleaning could solve. It's a strange pattern for a calibration issue though, I would have guessed it was something that needs cleaning, but that's apparently not the cause.

Cheers,
Bart

[Christoph B.]

Hi,

If the patterns do not change (get sharper or blurrier) when you change the aperture, then it must be something in the sensor, and requires a service calibration. If there is a difference in sharpness when you vary the aperture, then it is something in front of the sensor itself, casting a sort of shadow (sharper with narrower apertures).

From your description it seems to be sensor calibration related and not something that cleaning could solve. It's a strange pattern for a calibration issue though, I would have guessed it was something that needs cleaning, but that's apparently not the cause.

Cheers,
Bart

I think that applies to smaller individual particles but not a collection of dust/debris/residue which covers a bigger area. It's not such a singular, clear, dark spot but more of a smudge in a pentagonal shape.

[Christoph B.]

Okay so I went over the files once more and it seems that it is somewhat related to the aperture Setting - it becomes much more visible when you stop down (f8-16) and less visible when you use a bigger aperture (2.8-5.6).

I think it has to be something either between the sensor and the IR filter OR maybe the IR filter itself. Could it be that there's some stress in the IR-glass? Something like stretching and compression in the glass itself?

Anyway I contacted the dealer from whom I bought the back (in EU we have 2 years of warranty on used items) to sort it out. A crumb of comfort.

[Graham Welland]

1) Have your Phase One Dealer clean the sensor, possibly using the detergent and then the typical cleaner afterwards.

if (1) doesn't work, and I'd ask your dealer to fully test the cleaning before you do, get your dealer to send it to Phase One or take their fix suggestions.

[Christoph B.]

1. My P1 dealer has already seen the back and didn't see any dirt or smudges or anything else on the surface, it's superclean - even took a loupe to it and didn't find anything out of the ordinary. He cleaned it himself.

2. Phase One already told me and him separately to send it in, I seriously doubt it's something that can be solved by cleaning the sensor over and over again.

[Graham Welland]

In discussion with my tech at Capture Integration he shared that they'd seen aggressive cleaning / fluid remove some of the IR/UV coating. Maybe your issue?

[Christoph B.]

I think that would be visible from certain angles, but the surface looks very even and the coating seems intact - but another possibility. I still have to shoot with the back on Monday but the very next day I'll try to send it in.

[Christoph B.]

Alright so today (after a month! - yikes!) I got the P65+ back from PhaseOne, they did some recalibration (the files look much cleaner than they did before) and exchanged a few bits and pieces.
They also said they replaced the IR-Filter which cost a whopping 990€.

Now the strange shapes have disappeared (mostly, some tiny variations are still here but it's much better. However I did notice that the small scratches that were present before are still there - and some marks also line up with the scratches. But if PhaseOne really did exchange the IR Filter they would have to be gone, right?

I'm asking myself whether they actually replaced the filter or just cleaned the old one and re-used it, thinking it would be alright.

Here's a comparison, left before and right after the service:


edit: according to my PhaseOne dealer those aren't scratches, they are actually minor flaws in the sensor coating - under normal circumstances they aren't visible anyway

[Bart_van_der_Wolf]

edit: according to my PhaseOne dealer those aren't scratches, they are actually minor flaws in the sensor coating - under normal circumstances they aren't visible anyway

Hi,

Much better, so it was a(n odd) cleaning(?) issue with some sort of crystal deposit. However, I don't buy the sensor coating story. Maybe they meant sensor cover-glass AR coating?

Sensor chips are usually sealed with (non-replaceable) cover-glass in the same chip-assembly. The IR filter(stack) is a separate (replaceable) component. Maybe the sensor cover-glass (AR coating?) has a few minute scratches, but as you say, it wouldn't show under normal conditions.

Cheers,
Bart

[Christoph B.]

Yeah I think you're right, he meant the sensor cover glass coating - anyway I'm glad it's sorted out and because I bought the back from a 2nd hand dealer it didnt cost me a cent (well technically not true, I had to postpone a lot of shoots and some were cancelled because of this - but I didn't have to pay anything on top of that).

It seems that those strange artefacts were due to dirt behind the IR-Filter and some calibration-issues. As I said the noise is noticeably reduced.

The only thing that I find a bit annoying is that somehow they changed the standard sharpening preset on the back, which I now have to correct after every shoot until I find out how to change it back to my previous setting

But as I shoot tethered 90% of the time it's no big deal at all.