Black smudges on screen when taking exposure

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Mirrorgirl Great Britain
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Black smudges on screen when taking exposure

#1

Post by Mirrorgirl »


Hi there

When I take an exposure, on screen there appears to be like dark smudges on the image and it ruins my image when processing does anybody know what it is and what's causing it?

Thank you for your help.


Rhoda
Eqm35 Skywatcher mount..Skywatcher 80 ed telescope, 71 W/O GT ...bunch of eye pieces 25,mm 32mm etc...Nexter 4,se...385 mc Zwo camera, Zwo 183 colour cooled pro camera... Orion 80 ed...two compass...
Sky fi wireless telescope controller.. Rebel t3i.. light pollution L XTREME, Idas light pollution filter and Antlia 3nm gold, Antlia h alpha filter filter..other filters .. pixinsight .. startools..

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chris_g United States of America
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Re: Black smudges on screen when taking exposure

#2

Post by chris_g »


Mirrorgirl wrote: Fri Nov 04, 2022 12:40 pm Hi there

When I take an exposure, on screen there appears to be like dark smudges on the image and it ruins my image when processing does anybody know what it is and what's causing it?

Thank you for your help.


Rhoda
You're talking about the T3i? They are dust motes inside the body. Is your camera modified and had the cleaning function removed? If so, the only way to get it out is to hold it upside down and shake it loose or with a compressed can of air. I had a T2i that was modified full spectrum, it does the same thing. My 6D does it too but the cleaning function is still in place, so when I notice it, I pause my imaging plan and go out to the scope and run the cleaning routine manually, then delete any affected images. If I don't catch the issue until the end, I don't clean the sensor until after I've taken a good set of flats which should remove any anomalies like that. However, sometimes that doesn't work, and I have to handle the defect in post processing. I use PS and use its content aware fill function to blend the area.

Clear Skies,
Chris
Image Cam: Canon 6D (Ha mod), 600D (Stock), SVBony SV405CC
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EP: Baader Hyperion Modular Set
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Juno16 United States of America
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Re: Black smudges on screen when taking exposure

#3

Post by Juno16 »


Can you attach a stretched image?

If they are dust motes as Chris mentioned, flats should take care of them
Jim

Scopes: Explore Scientific ED102 APO, Sharpstar 61 EDPH II APO, Samyang 135 F2 (still on the Nikon).
Mount: Skywatcher HEQ5 Pro with Rowan Belt Mod
Stuff: ASI EAF Focus Motor (x2), Orion 50mm Guide Scope, ZWO 30 mm Guide Scope, ASI 220mm min, ASI 120mm mini, Stellarview 0.8 FR/FF, Sharpstar 0.8 FR/FF, Mele Overloock 3C.
Camera/Filters/Software: ASI 533 mc pro, ASI 120mm mini, Orion SSAG, IDAS LPS D-1, Optolong L-Enhance, ZWO UV/IR Cut, N.I.N.A., Green Swamp Server, PHD2, Adobe Photoshop CC, Pixinsight.
Dog and best bud: Jack
Sky: Bortle 6-7
My Astrobin: https://www.astrobin.com/users/Juno16/
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Mirrorgirl Great Britain
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Re: Black smudges on screen when taking exposure

#4

Post by Mirrorgirl »


Juno16 wrote: Fri Nov 04, 2022 6:55 pm Can you attach a stretched image?

If they are dust motes as Chris mentioned, flats should take care of them
when I got them, I never put my dew heaters on the telescope I'm out now with dew heaters on and also before I came out, I cleaned the optics and it seems to have made the problem much better, thank you.

I will still send an image when I come in so you can see.

Thanks

Rhoda.
Eqm35 Skywatcher mount..Skywatcher 80 ed telescope, 71 W/O GT ...bunch of eye pieces 25,mm 32mm etc...Nexter 4,se...385 mc Zwo camera, Zwo 183 colour cooled pro camera... Orion 80 ed...two compass...
Sky fi wireless telescope controller.. Rebel t3i.. light pollution L XTREME, Idas light pollution filter and Antlia 3nm gold, Antlia h alpha filter filter..other filters .. pixinsight .. startools..

:observatory: NONE :observatory:
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JayTee United States of America
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Re: Black smudges on screen when taking exposure

#5

Post by JayTee »


This Thread is more appropriate in this forum. Thanks for playing our home game.
∞ Primary Scopes: #1: Celestron CPC1100 #2: 8" f/7.5 Dob #3: CR150HD f/8 6" frac
∞ AP Scopes: #1: TPO 6" f/9 RC #2: ES 102 f/7 APO #3: ES 80mm f/6 APO
∞ G&G Scopes: #1: Meade 102mm f/7.8 #2: Bresser 102mm f/4.5
∞ Guide Scopes: 70 & 80mm fracs -- The El Cheapo Bros.
∞ Mounts: iOptron CEM70AG, SW EQ6, Celestron AVX, SLT & GT (Alt-Az), Meade DS2000
∞ Cameras: #1: ZWO ASI294MC Pro #2: 662MC #3: 120MC, Canon T3i, Orion SSAG, WYZE Cam3
∞ Binos: 10X50,11X70,15X70, 25X100
∞ EPs: ES 2": 21mm 100° & 30mm 82° Pentax XW: 7, 10, 14, & 20mm 70°

Searching the skies since 1966. "I never met a scope I didn't want to keep."

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Juno16 United States of America
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Re: Black smudges on screen when taking exposure

#6

Post by Juno16 »


Excellent! The dreaded dust mote!

No matter how much you clean, they always come back!

Flats!

Good luck tonight!
Jim

Scopes: Explore Scientific ED102 APO, Sharpstar 61 EDPH II APO, Samyang 135 F2 (still on the Nikon).
Mount: Skywatcher HEQ5 Pro with Rowan Belt Mod
Stuff: ASI EAF Focus Motor (x2), Orion 50mm Guide Scope, ZWO 30 mm Guide Scope, ASI 220mm min, ASI 120mm mini, Stellarview 0.8 FR/FF, Sharpstar 0.8 FR/FF, Mele Overloock 3C.
Camera/Filters/Software: ASI 533 mc pro, ASI 120mm mini, Orion SSAG, IDAS LPS D-1, Optolong L-Enhance, ZWO UV/IR Cut, N.I.N.A., Green Swamp Server, PHD2, Adobe Photoshop CC, Pixinsight.
Dog and best bud: Jack
Sky: Bortle 6-7
My Astrobin: https://www.astrobin.com/users/Juno16/
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JayTee United States of America
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Re: Black smudges on screen when taking exposure

#7

Post by JayTee »


I did an in-depth investigation of the dreaded dust motes. I inspected, then cleaned, then inspected again every optical surface in the image train. They were still there! I was too timid to inspect let alone touch my camera's sensor. But those motes turned me into a wild man and I said "damn the timidity, deal with that sensor." So I took a 10X loupe and inspected the sensor on my ZWO ASI 120MC and lo and behold that's where those pesky dust particles were living.

I then read about cleaning your camera sensor, followed the advice and magically the dust particles were gone and so were those malicious motes!
∞ Primary Scopes: #1: Celestron CPC1100 #2: 8" f/7.5 Dob #3: CR150HD f/8 6" frac
∞ AP Scopes: #1: TPO 6" f/9 RC #2: ES 102 f/7 APO #3: ES 80mm f/6 APO
∞ G&G Scopes: #1: Meade 102mm f/7.8 #2: Bresser 102mm f/4.5
∞ Guide Scopes: 70 & 80mm fracs -- The El Cheapo Bros.
∞ Mounts: iOptron CEM70AG, SW EQ6, Celestron AVX, SLT & GT (Alt-Az), Meade DS2000
∞ Cameras: #1: ZWO ASI294MC Pro #2: 662MC #3: 120MC, Canon T3i, Orion SSAG, WYZE Cam3
∞ Binos: 10X50,11X70,15X70, 25X100
∞ EPs: ES 2": 21mm 100° & 30mm 82° Pentax XW: 7, 10, 14, & 20mm 70°

Searching the skies since 1966. "I never met a scope I didn't want to keep."

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