Spots on CCD sensor glass

[ghoonk]

So, I'm back from a trip to the Swiss Alps, and during the process of cleaning the sensor glass, I notice this:

When the sensor glass is clean and dry, it's pristine.
When I breathe onto the glass, I can see spots. Given that the moisture is on the surface of the glass, I'm guessing that these spots exist ON the surface facing out (if the spots were on the underside of the glass, the moisture from my breath shouldn't reveal it)

Is this something I should be concerned about? Is there a way to clean this? These spots do not show up on any of my images.

 

[Thierry]

dear ghoonk,

As long as you don't notice the spots in your images I would say to not bother too much.

You can try to clean it though, by using what is usually used to clean the protecting cover/glass of sensors: use first a/the cleaning agent by wetting a non-woven fabric and wipe it in one direction over the glass. Do this a few times but always in the same direction. After that you must use a specific alcohol (purified ethanol) with another clean fabric and wipe it over a few times to get a uniform clean surface.

That should get rid of any dust, saliva or other spots on the external surface of the glass protection.

Best regards
Thierry

So, I'm back from a trip to the Swiss Alps, and during the process of cleaning the sensor glass, I notice this:

When the sensor glass is clean and dry, it's pristine.
When I breathe onto the glass, I can see spots. Given that the moisture is on the surface of the glass, I'm guessing that these spots exist ON the surface facing out (if the spots were on the underside of the glass, the moisture from my breath shouldn't reveal it)

Is this something I should be concerned about? Is there a way to clean this? These spots do not show up on any of my images.

 

[Christopher]

This is a good place to ask a question which bugged me a long time. I always clean my IQ180 and the P65/P45 before that with the cleaning solution from Phase one.

However, a few weeks ago i was shooting with a friend how owned a IQ160 and was a little shocked and surprised. Before going out, he took the back off, took a fine micro fiber cloth and just cleaned it like that. (Kinda how I clean a lens) I asked him why he did it like that and he told me he used the cleaning solutions only for spots which won't come off easily, for all other things he used the micro fiber cloth. The main argument was, that the cover glass is actual glass and like glass there is no way you could scratch it with such a fine cloth.

So what would you say ? Is that possible or is it something you would never do? I mean what was impressive is that it took him only a hugely small amount of time to clean it perfectly.

 

[MaxKißler]

I suggest not to do it this way or at least not on a daily basis. Since I'm wearing glasses, I clean them with a micro fiber cloth at least once a day and after app. one year I'm having tiny scratches in the glass or in the coating. They don't bother me on my glasses but thinking of having them in my back isn't too convenient.

I recommend using a blower for quick cleaning. Anything that isn't coming off easily will only damage your back when using a cloth. That is what the cleaning solution is for.

 

[Thierry]

Christopher,

I would never do this. This glass is not a simple glass, it is a IR filter in front of the sensor and it costs about Euro 800,- to 1'000,- to replace.

Even if glass it can be scratched, for example if there is a tiny grain of sand or something similar and hard on it. You will definitively scratch it sooner or later by doing so.

And before using the cleaning agents one should use a blower to blow away all possible dust and other dirt on it.

Best regards
Thierry

This is a good place to ask a question which bugged me a long time. I always clean my IQ180 and the P65/P45 before that with the cleaning solution from Phase one.

However, a few weeks ago i was shooting with a friend how owned a IQ160 and was a little shocked and surprised. Before going out, he took the back off, took a fine micro fiber cloth and just cleaned it like that. (Kinda how I clean a lens) I asked him why he did it like that and he told me he used the cleaning solutions only for spots which won't come off easily, for all other things he used the micro fiber cloth. The main argument was, that the cover glass is actual glass and like glass there is no way you could scratch it with such a fine cloth.

So what would you say ? Is that possible or is it something you would never do? I mean what was impressive is that it took him only a hugely small amount of time to clean it perfectly.

 

[GrahamWelland]

P2500 sandpaper works well - not too rough and guaranteed to remove spots although the downside is that the glass gets a little opaque over time.

(just kidding btw - NOT serious )

 

[Shashin]

Well, that is the advantage of MFD backs--you can just lick the sensor clean. I just can't get my tongue anywhere near the sensor in the 645D.

 

[jcoffin]

Well, that is the advantage of MFD backs--you can just lick the sensor clean. I just can't get my tongue anywhere near the sensor in the 645D.

A little spit and a quick swipe with the tail of a T-shirt should work nicely. If you're shooting B&W, a selection of colored T-shirts can save lots on filters too (Robin Trower "This was now, 1999" T-shirt = #25 filter).

 

[Steve Hendrix]

This is a good place to ask a question which bugged me a long time. I always clean my IQ180 and the P65/P45 before that with the cleaning solution from Phase one.

However, a few weeks ago i was shooting with a friend how owned a IQ160 and was a little shocked and surprised. Before going out, he took the back off, took a fine micro fiber cloth and just cleaned it like that. (Kinda how I clean a lens) I asked him why he did it like that and he told me he used the cleaning solutions only for spots which won't come off easily, for all other things he used the micro fiber cloth. The main argument was, that the cover glass is actual glass and like glass there is no way you could scratch it with such a fine cloth.

So what would you say ? Is that possible or is it something you would never do? I mean what was impressive is that it took him only a hugely small amount of time to clean it perfectly.

I would generally not recommend cleaning any glass surface that is valued with a dry cloth, no matter how "soft" the cloth may appear to be. And when utilizing a cleaning solution, a fresh wipe should always be used, you should avoid re-using a wipe.


Steve Hendrix

 

[Guy Mancuso]

BTW Leaf cleaning cloths are the best around. They are actually called Clear Clean
Microweb UD-G CC 133d-115. They are made in Germany and we need to thank Mr Hendrix for getting me these a long time ago but they are outstanding wipes. Its all I use. I agree with Thierry and Steve here don't screw around with that sensor glass. Clean it with wet solution

 

[Guy Mancuso]

BTW Steve i still need another pack if you would put that down for me. I think they are backordered not sure

 

[Steve Hendrix]

BTW Leaf cleaning cloths are the best around. They are actually called Clear Clean
Microweb UD-G CC 133d-115. They are made in Germany and we need to thanks Mr Hendrix for getting me these a long time ago but they are outstanding wipes. Its all use

The ironic thing is that when we sell a Phase One system, we almost always sell a pack of cleaning wipes from Leaf (and recommend they toss the wipes that come with the Phase One cleaning kit).

When we sell a Leaf digital system (which comes with wipes, but no solution), we almost always sell a Phase One cleaning kit with it to use the solution from the kits with the Leaf cleaning wipes.




Steve Hendrix

 

[Guy Mancuso]

That is pretty funny. Seriously these really are fantastic cleaning cloths . Not cheap mind you but worth it.

 

[Steve Hendrix]

That is pretty funny. Seriously these really are fantastic cleaning cloths . Not cheap mind you but worth it.

True that on the price ($30 for a pack of, I think it is 25 or so). But really, they should last a reasonable amount of time. Most of the time I am using a dust brush. It is not that frequently that I have something on an IR Filter that needs to be removed with solution/wipes, though I don't have the time to shoot on a full time schedule, and I realize it is different with full time use. For me, usually it is dust, and airborne stufficles.

We have invested a considerable amount of time trying to find less expensive alternatives, and are still in the process of doing so, but typically what we're trying out is somewhere between the Phase wipes and the Leaf wipes in terms of effectiveness, so we'll continue to sample and test.


Steve Hendrix

 

[ghoonk]

Hey guys, thanks for the replies. The sandpaper did the trick!

just kidding.

I've been cleaning the sensor as Thierry and Steve suggested using the Phase One Cleaning Kit, exactly as described, thanks to siebel who showed me how to do it correctly.

My cleaning procedure is as such:

1. Use blower to clear off any loose particles. This usually works, unless there are spots, in which case, I go to Step 2
2. With the Phase One Cleaning Kit, I fold the cleaning fabric in half, wrap it around the white squeegee, dab Solution A across the entire edge and wait a couple of seconds for the solution to spread evenly across the fabric
3. One swipe, smoothly across one edge of the sensor to the other. Take approx 2 seconds to go end to end
4. Remove 1st wipe, clean squeegee, wrap 2nd fabric wipe around squeegee, dab Solution B across the wipe, and swipe across sensor before Solution A dries out.

Result: Perfectly clean sensor. However, if i fog the sensor glass gently with my breath, some spots appear that look like someone sneezed on the sensor. Still no clue what's caused it, but someone mentioned that I shouldn't be breathing on the sensor as it would introduce moisture anyway. I was under the impression that these backs were a lot tougher than that - I step out of an air-conditioned environment into the heat of Dubai, and would pretty much expect some condensation from the transition, and I don't shoot till I'm out there for awhile anyway.

 

[goesbang]

Hey guys, thanks for the replies. The sandpaper did the trick!

just kidding.

I've been cleaning the sensor as Thierry and Steve suggested using the Phase One Cleaning Kit, exactly as described, thanks to siebel who showed me how to do it correctly.

My cleaning procedure is as such:

1. Use blower to clear off any loose particles. This usually works, unless there are spots, in which case, I go to Step 2
2. With the Phase One Cleaning Kit, I fold the cleaning fabric in half, wrap it around the white squeegee, dab Solution A across the entire edge and wait a couple of seconds for the solution to spread evenly across the fabric
3. One swipe, smoothly across one edge of the sensor to the other. Take approx 2 seconds to go end to end
4. Remove 1st wipe, clean squeegee, wrap 2nd fabric wipe around squeegee, dab Solution B across the wipe, and swipe across sensor before Solution A dries out.

Result: Perfectly clean sensor. However, if i fog the sensor glass gently with my breath, some spots appear that look like someone sneezed on the sensor. Still no clue what's caused it, but someone mentioned that I shouldn't be breathing on the sensor as it would introduce moisture anyway. I was under the impression that these backs were a lot tougher than that - I step out of an air-conditioned environment into the heat of Dubai, and would pretty much expect some condensation from the transition, and I don't shoot till I'm out there for awhile anyway.

It seems that you were paying attention, Grasshopper.
Please do the following test - Shoot a frame with the LCC filter over the lens, any lens. Get your exposure to sit in the middle of the histogram. Then, pull your black point and your white point on your curves much closer together, so that you now have a very steep curve. If your "invisible" spots are having any impact on your images, you will now see it as plainly as the logo on the front of your camera.....

 

[ghoonk]

I shot the LCC, loaded into PS, set up lens corrections, tweaked exposure so that it sits in the middle of the histogram. Pulled BP and WP in much closer, and......

nothing. It's a nice shade of blue.

Nothing to worry about then?

 

[MGrayson]

As long as you did the test at the highest f-number (smallest aperture) you ever plan to use, then yes.

--Matt

 

[ghoonk]

Right, thanks for the reminder! Time to shoot again at f32 and see what happens!

 

[MGrayson]

Just don't panic when you see the results. In the absence of a perfectly uniform image, you can always set the levels so that the resulting image looks terrible.
Just be reasonable.

-- Matt