Annother F200 EXR Hotpixel nightmare

EmmeBi said:

Hi all

I recently bought a F200exr. I am very happy with it, but now I have found a very annoying white dot which comes out in most of my 6M shots (P mode): I can see it in about the 90% of my shots, and it is ALWAYS in the same position.

The very strange thing is that such dot (about 2 x 2 white pixels surrounded by a dark edge) is NEVER there when I shot at 12 M.>

EmmeBi

Click to expand...

The "dark edge" could be a result of the "film type" you have set. I always use "standard", but the F200exr can be set to a "more vivid" type - do you use that?
--
Russell
Galleries at http://www.pbase.com/russ

I always use the "standard" color setting, and the problem occurs even at the 1st shot (and so with no camera heating).

Regards,
EmmeBi

EmmeBi said:

Any idea or suggestion?

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Looks like a "stuckpixel" aka deadpixel (=defective pixel)

Every image sensor has some defective pixels, but they should be mapped out from the image-processor.

It seems that on your cameras sensor one additional photosite got defect after the manufacturing, so it´s position isn´t stored in the camera.

Unfortunately there is no way to update the map for the defective pixels on your own on the F200, but this shouldn´t be a problem for a Fuji servicecenter.

It´s strange, that this only happens in 6MP-mode, actually it should be more visible in 12MP. Maybe the stronger NR in 12MP detects this as noise and removes it.

EXR said:

EmmeBi said:

Any idea or suggestion?

Click to expand...

Looks like a "stuckpixel" aka deadpixel (=defective pixel)

Every image sensor has some defective pixels, but they should be mapped out from the image-processor.

It seems that on your cameras sensor one additional photosite got defect after the manufacturing, so it´s position isn´t stored in the camera.

Click to expand...

I'm glad to see you"re looking into this, EXR; you seem to be very aware of how the Fuji cameras work. If you read the other items in the thread (and visit my gallery on the subject), you'll see they deal with a multiplicity of "hot pixels"; EmmeBi showed just one, as an example. I hope you have time to go into this deeper.

EXR said:

Unfortunately there is no way to update the map for the defective pixels on your own on the F200, but this shouldn´t be a problem for a Fuji servicecenter.

It´s strange, that this only happens in 6MP-mode, actually it should be more visible in 12MP. Maybe the stronger NR in 12MP detects this as noise and removes it.

Click to expand...

--
Russell
Galleries at http://www.pbase.com/russ

Dear EXR

Thank you very much for your detailed explanation: this makes sense to me!

Anyhow I did not find this white dot in the early shots I took with this camera, so I am wondering: is it possible that this problem came with the firmware updating I did some weeks ago?

Regards,
Emmebi

Russ Yost said:

I'm glad to see you"re looking into this, EXR; you seem to be very aware of how the Fuji cameras work. If you read the other items in the thread (and visit my gallery on the subject), you'll see they deal with a multiplicity of "hot pixels"; EmmeBi showed just one, as an example. I hope you have time to go into this deeper.

Click to expand...

You have to distinguish between stuckpixel/deadpixel and hotpixel.

Stuckpixels/Deadpixels are photosites which are broken and are either always fully charged (=white) or not at all (=black). This is similar to a pixelerror on a LCD.

Every sensor has some broken pixels which are detected after manufacturing and stored in the camera to be removed during image processing. Some cameras also allow to update this map of broken pixels in their settings.

Hotpixels are a different story. They work usually just normal.

But with long exposures there are always some photosites that "overload" (=become white) even though no/not many photons hit them.

The positions and number of hotpixels change over time and depending on temperature, exposure time etc.

Therefore you can´t remove them directely, but you can take a darkframe with the same exposure-settings to get the positions of the hotpixels and remove them.

Some cameras do this automatically, some optionally, and others (like the F200 not at all)

I also don´t think the hotpixels in the first image are that bad, certainly above average but not that uncommon for a 8s exposure.

EmmeBi said:

Hi all

I recently bought a F200exr. I am very happy with it, but now I have found a very annoying white dot which comes out in most of my 6M shots (P mode): I can see it in about the 90% of my shots, and it is ALWAYS in the same position.

The very strange thing is that such dot (about 2 x 2 white pixels surrounded by a dark edge) is NEVER there when I shot at 12 M.

Click to expand...

Go again to http://upload.pbase.com/edit_gallery/russ/f200exrhotpiixels

to see my results at 12MN; I see the problem iis still there, very similar to IQ 6MN.

--
Russell
Galleries at http://www.pbase.com/russ

EXR said:

I also don´t think the hotpixels in the first image are that bad, certainly above average but not that uncommon for a 8s exposure.

Click to expand...

Glad to see you again...ok for 8s but you said you have no such situation till 3s or 4s...how is it possible when all our results instead give this problem evident!?

In my pics from 1,3s or 1,6s at ISO100 and from 1\2s at ISO200....

Russ Yost said:

EmmeBi said:

Hi all

I recently bought a F200exr. I am very happy with it, but now I have found a very annoying white dot which comes out in most of my 6M shots (P mode): I can see it in about the 90% of my shots, and it is ALWAYS in the same position.

The very strange thing is that such dot (about 2 x 2 white pixels surrounded by a dark edge) is NEVER there when I shot at 12 M.

Click to expand...

Go again to http://upload.pbase.com/edit_gallery/russ/f200exrhotpiixels

to see my results at 12MN; I see the problem iis still there, very similar to IQ 6MN.

--
Russell
Galleries at http://www.pbase.com/russ

Click to expand...

My shots say more...at 12Mp white dots are worst than at 6Mp! and in M mode (or else) it is better to use only DR100% at night....or these stars come out :-(

jobocam said:

Glad to see you again...

Click to expand...

I was on holiday last week and invited to a wedding over last weekend so I couldn´t be here on the forum.

jobocam said:

ok for 8s but you said you have no such situation till 3s or 4s...how is it possible when all our results instead give this problem evident!?

Click to expand...

I don´t know that´s the thing about hotpixels, they are always different.

I also don´t see how ALL your results have big problems with hotpixels. I have seen yours and I think there was someone else, but I have seen many nightshots of the F200 with only a few or no hotpixels at all.

As I said I also dont´t think the first picture in this thread is that bad for 8s, I´m used to see less hotpixels with my F200, but I wouldn´t say that under some circumstances my cam would produce a similar amount of hotpixels.

Here a picture at 5s I shot last week.



Unfortunately I had no tripod and there is obvously a lot of shake in this picture.

EXR said:

I was on holiday last week and invited to a wedding over last weekend so I couldn´t be here on the forum.

EXR said:

ok for 8s but you said you have no such situation till 3s or 4s...how is it possible when all our results instead give this problem evident!?

Click to expand...

I don´t know that´s the thing about hotpixels, they are always different.

I also don´t see how ALL your results have big problems with hotpixels. I have seen yours and I think there was someone else, but I have seen many nightshots of the F200 with only a few or no hotpixels at all.

As I said I also dont´t think the first picture in this thread is that bad for 8s, I´m used to see less hotpixels with my F200, but I wouldn´t say that under some circumstances my cam would produce a similar amount of hotpixels.

Click to expand...

Really appreciate your time and pic about this problem.
Seems to me not, but...Is there any kind of PP (like hotpixel eliminator)?

I think your 5s shot is quite a pearl towards mine (ours)...seems my 3s or 2s (ISO100) is similar to your shot.

I know that conditions\situation may be various but it seems that ours F200exr are more prone to fall in such white dots problem (at minus "s" shutter speed)...of this digicam, you have the "jewel" and we have the "rings" ?!?! :-o