Strange purple blotch from M8 pictures

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sakkapop

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Hi all, I am a new M8 owner. I am very curious about pictures I took. I found one strange purple blotch at the same position taken by all lenses I have. What make me very curious it is that it is pale purple, not black. How's this possible. It is more visible when shooting wide open. What is really my problem? Should I clean the sensor and hope it will disappear? Many thanks for your inputs.
 
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If its more intrusive when shooting with smaller apertures its most likely dust on the sensor. Stop down to f16 and take a picture of a uniform subject, e.g. and area of blue sky without clouds, and you should show up all dust specs on the sensor.
 
Thank you very much for your input. Ezzie. I just edited my typo. In fact, it is more visible shooting wide open. That is why I am so curious about it. At F16, it's hardly been noticed. It looks like strain, but it is purple!
 
sakkapop said:
Hi all, I am a new M8 owner. I am very curious about pictures I took. I found one strange purple blotch at the same position taken by all lenses I have. What make me very curious it is that it is pale purple, not black. How's this possible. It is more visible when shooting wide open. What is really my problem? Should I clean the sensor and hope it will disappear? Many thanks for your inputs.
Click to expand...

http://www.luminous-landscape.com/reviews/cameras/m8-solution.shtml
 
A fault that is uniform in size and location no matter the lens or subject would seem to suggest dust on the sensor, would it not? Excessive CA and other faults would not manifest themselves uniformly.
 
Agree to Ezzie and others that this should be dust or oil, or even worse sometime wrong with the sensor. Can it be pale purple if it is actually dust or oil strain? From my own experience, I've seen only gray or black strain. I will try to use blower first and see how it works. Many thanks.

A fault that is uniform in size and location no matter the lens or subject would seem to suggest dust on the sensor, would it not? Excessive CA and other faults would not manifest themselves uniformly.
Click to expand...
 
sakkapop, do you have a sample shot with one of these splotches? I'm having the same issue. A small splotch in the same part of the frame regardless of which lens I use. Is that what you're seeing? My guess is it's something on the sensor... dust or oil.
 
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robklurfield: I will try to post its picture soon. You have the same problem? Once I zoomed in, I saw splotches (irregular coloured purple strains for each pixels). Have you tried a blower?

sakkapop, do you have a sample shot with one of these splotches? I'm having the same issue. A small splotch in the same part of the frame regardless of which lens I use. Is that what you're seeing? My guess is it's something on the sensor... dust or oil.
Click to expand...
 
I have one very small dot. I ran my M8 in sensor cleaning mode and think there's something on the sensor. Before I try cleaning it, I want to be sure if the right stuff (there's a thread or two on the site about this topic; didn't have time to find them today).

Here's a sample (see the small dot above the roofline):
4027267037_2d2be0c143_b.jpg

I think this is an easy fix. Is this the problem you're having (but, I assume, in color, of course)?
Rob

sakkapop said:
robklurfield: I will try to post its picture soon. You have the same problem? Once I zoomed in, I saw splotches (irregular coloured purple strains for each pixels). Have you tried a blower?
Click to expand...
 
This is the picture with that strange purple spot. I took this underexposured picture at ISO2500. It is the center of the picture. It happens in every pictures (same position). Hope you can find it 😀 In fact, it does not practically affect picture. But I am very curious to know what is it.
I tried to use a blower, but it is still there. My best guess is that it is oil (like nikonhs said).


iso2500b.jpg
 
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In Rob´s case it definitely is something on the sensor. Either dust or oil. My R-D1 had a few of these. Light cleaning with a nylon static brush got rid of all but one, which I think must be oil.
 
I´ve not yet tried to remove the last stubborn piece of dirt. It may be oil, it may not. From what I´ve heard, lubrication oil on the shutter mechanism can transfer to the sensor.
 
British yes, but Triumph not

British yes, but Triumph not

Benjamin said:
Probably a Triumph!
Click to expand...

A Land Rover. They leak copiously, My two alone keep the Norwegian oil industry in business. Seriously, I wouldn´t fool around when cleaning the sensor. Rich Cutler has covered all aspects of Epson R-D1 sensor cleaning on his pages and I suspect that can be applied to the M8 as well. If you haven´t done it before look up his pages here
 
ezzie, thanks for the link to rich culter's site.
Ezzie said:
A Land Rover. They leak copiously, My two alone keep the Norwegian oil industry in business. Seriously, I wouldn´t fool around when cleaning the sensor. Rich Cutler has covered all aspects of Epson R-D1 sensor cleaning on his pages and I suspect that can be applied to the M8 as well. If you haven´t done it before look up his pages here
Click to expand...
 
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