HELP How clean, erase or remap sensor for HOT PIXELS?? HELP!

[Jowe-79]

Hi people, I have had the EOS R7 for 2 months and yesterday while taking a long exposure of 2sc 25 sec 30 sec 15 sec... at night I noticed that green and red hot pixels appear in some areas of the frame, even at ISO 100... They are always in the same place... if I expose for more seconds they are more visible, but the strange thing is that if I raise the ISO 3200 or 6400 those bright spots (hot pixels) disappear... how can this be? Or am I not right? Are these hot pixels normal? I should say that the ambient temperature in my area yesterday was 29 degrees at 9:00 p.m. (Barcelona) does it influence? Should I use the warranty? Maybe at 30 sec iso 100 I saw about 10 or 12 bright pixels... (hot)... Obviously if I activate the LENR they all disappear due to the black photo that the camera takes but it takes twice as long... and I want to make circumpolars of stars at night and I'm afraid of the damn hot pixels... Is there any way to eliminate or remap the sensor to eliminate those hot pixels? In the EOS R7 does cleaning the sensor manually for 1 minute with the lens cap on and repeating it 2 or 3 times work? Any software that detects the hot pixels in the frame and eliminates them? Are hot pixels inevitable? How do you do it? Well I hope for help from the sensor gurus here... I've heard of software like DARKFRAME for Windows that works with a click and is very effective... is that so? Thanks

 

[charlyw64]

Obviously if I activate the LENR they all disappear due to the black photo that the camera takes but it takes twice as long... and I want to make circumpolars of stars at night and I'm afraid of the damn hot pixels... Is there any way to eliminate or remap the sensor to eliminate those hot pixels?

You would botch your output considerably for normal photography if that would be possible.

In the EOS R7 does cleaning the sensor manually for 1 minute with the lens cap on and repeating it 2 or 3 times work?

Nope! It luckily won't!

Any software that detects the hot pixels in the frame and eliminates them?

There is plenty of software that can apply a dark frame afterwards, that's equivalent to the LENR. You should take a dark frame at the beginning and the end of your series of shots, then that software can do it's work...

Are hot pixels inevitable?

Yes!

Have a go with StarStax for example - with some manually taken darkframes. It should be available for your flavor of operating system.

 

[Jowe-79]

Obviously if I activate the LENR they all disappear due to the black photo that the camera takes but it takes twice as long... and I want to make circumpolars of stars at night and I'm afraid of the damn hot pixels... Is there any way to eliminate or remap the sensor to eliminate those hot pixels?

You would botch your output considerably for normal photography if that would be possible.

In the EOS R7 does cleaning the sensor manually for 1 minute with the lens cap on and repeating it 2 or 3 times work?

Nope! It luckily won't!

It's Strange i read a lot of posts that is anunnofficial methode, but works...apart of clean sensor of dust, remaps the hot pixels too... it's really false???? All people lies about this???

Anybody knows if is a tested method?

Any software that detects the hot pixels in the frame and eliminates them?

There is plenty of software that can apply a dark frame afterwards, that's equivalent to the LENR. You should take a dark frame at the beginning and the end of your series of shots, then that software can do it's work...

Are hot pixels inevitable?

Yes!

Have a go with StarStax for example - with some manually taken darkframes. It should be available for your flavor of operating system.

 

[charlyw64]

It's Strange i read a lot of posts that is anunnofficial methode, but works...apart of clean sensor of dust, remaps the hot pixels too... it's really false???? All people lies about this???

If anything that method only maps out hot pixels that show up in short exposures. Never ever those that come up in long exposures. It possibly is a case of placebo effect (I have been around since the 10D and this rumored "fix" has been around for as long as I use a DSLR)...

Edit: I have written numerous books, been technical editor for some more camera books on Canon DSLR in the past, I had contact to technical support both in the EU and US and no one there ever confirmed that the cleaning did anything to the hot pixels in short exposures either.

 

[JohnMoyer]

Obviously if I activate the LENR they all disappear due to the black photo that the camera takes but it takes twice as long... and I want to make circumpolars of stars at night and I'm afraid of the damn hot pixels... Is there any way to eliminate or remap the sensor to eliminate those hot pixels?

You would botch your output considerably for normal photography if that would be possible.

In the EOS R7 does cleaning the sensor manually for 1 minute with the lens cap on and repeating it 2 or 3 times work?

Nope! It luckily won't!

It's Strange i read a lot of posts that is anunnofficial methode, but works...apart of clean sensor of dust, remaps the hot pixels too... it's really false???? All people lies about this???

Anybody knows if is a tested method?

Any software that detects the hot pixels in the frame and eliminates them?

There is plenty of software that can apply a dark frame afterwards, that's equivalent to the LENR. You should take a dark frame at the beginning and the end of your series of shots, then that software can do it's work...

Are hot pixels inevitable?

Yes!

Have a go with StarStax for example - with some manually taken darkframes. It should be available for your flavor of operating system.

To me, the clean sensor now from the camera menu does hide some of the hot pixels.

Also, one may make a dark frame by keeping exactly the same camera settings and making a photo with the lens cap on.

I know little of astro photography and have been trying to teach myself. But, I do have some experience with image processing.

Recently, I tried to get some photos of a meteor shower. None ended up good enough to publish. But, I used graphicsMagick command line program to subtract a dark frame and it did eliminate the hot pixels.

It was as simple as saving 16 TIFF files from Canon DPP software and

<pre>

/opt/local/bin/gm composite -verbose -compose minus IMG_1192c.TIF IMG_1183c.TIF IMG_1192c_minus_IMG_1183c.TIF

</pre>

I used macPorts to build graphicsMagick on my iMac, but I usually use it on my Debian machine. ImageMagick works the same way. Both are free software.

 

[Kameratrollet]

As JohnMoyer wrote, "Clean Now" is what removes bad pixels. It will not remove those at long exposures, so go for the dark frame. RawTherapee and ART have that feature.

The reason why your bad pixels are gone at higher ISO may be due to your raw converter.

With R5/R6/R3 it seems like bad pixels are removed in camera at ISO 12800 and above.

 

[Le Kilt]

It's Strange i read a lot of posts that is anunnofficial methode, but works...apart of clean sensor of dust, remaps the hot pixels too... it's really false???? All people lies about this???

If anything that method only maps out hot pixels that show up in short exposures. Never ever those that come up in long exposures. It possibly is a case of placebo effect (I have been around since the 10D and this rumored "fix" has been around for as long as I use a DSLR)...

Edit: I have written numerous books, been technical editor for some more camera books on Canon DSLR in the past, I had contact to technical support both in the EU and US and no one there ever confirmed that the cleaning did anything to the hot pixels in short exposures either.

And yet the method works. Tried and tested personnally on several EOS cameras, and many here have reported it workin also.

 

[charlyw64]

It's Strange i read a lot of posts that is anunnofficial methode, but works...apart of clean sensor of dust, remaps the hot pixels too... it's really false???? All people lies about this???

If anything that method only maps out hot pixels that show up in short exposures. Never ever those that come up in long exposures. It possibly is a case of placebo effect (I have been around since the 10D and this rumored "fix" has been around for as long as I use a DSLR)...

Edit: I have written numerous books, been technical editor for some more camera books on Canon DSLR in the past, I had contact to technical support both in the EU and US and no one there ever confirmed that the cleaning did anything to the hot pixels in short exposures either.

And yet the method works. Tried and tested personnally on several EOS cameras, and many here have reported it workin also.

I haven't seen any indications that it truly works, in many cases the reports are down to not using the camera for a few hours which reduced the temperature and in consequence apparently fixed the problem - and I have been around this for 25 years and none of my high ranking Canon contacts ever indicated it would work.

 

[EJ Fudd]

Hot pixels or effect with long exposures you can try sending the camera in and see if Canon can remount the sensor. I’m not sure if they do that most likely there will be a charge.

 

[charlyw64]

Hot pixels or effect with long exposures you can try sending the camera in and see if Canon can remount the sensor. I’m not sure if they do that most likely there will be a charge.

Hot pixels in long exposures are a fact of life in digital photography - Canon will not do anything about them because the camera has the means to deal with them.

Edit: The only times ever that Canon did anything because of noise were a few cases where a D60 (yes, I mean D60, not a 60D) lost its calibration data and the CMOS sensor output looked like a work by Jackson Pollock - in these rare cases the camera got a new mainboard and sensor IIRC...