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Strange image in Skywatcher Evostar 150 ED mirror

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#1 bluesilver

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Posted 14 August 2020 - 11:47 PM

 Hi, I am hoping someone on here might be able to help or advise what this image is that i am seeing through my scope.

I have just got a delivery of a brand new Skywatcher Evostar 150 ED
I was just going about a few things checking it out.
I am completely new to these scope as i have always been using a Dobsonian.

I put a diagonal on and had a quick look through it and found what i thought was a smudge mark,
Thinking it was in the diagonal i tool it off but that was clear.
Then just looking straight through the scope i could still see it.
Thinking it was something on the front of the lens, had a look but all clear.
It appears to be inside of the scope.
I have attached a photo of it in the hope someone might be able to tell me what it is before i contact the company i purchased it off in Australia.
( Sorry first time at trying to attach an image on here )

To help explain the image a bit, the grey is just a background to help show the defect in question.
What i am asking about is the triangles that you can see,
What are they?
Is this normal?
Is there an issue with the scope that i need to send it back?Capture.JPG



#2 clusterbuster

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Posted 15 August 2020 - 12:35 AM

Hi,

 Is it just a REFLECTION of something on the lens ?

Mark



#3 bluesilver

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Posted 15 August 2020 - 12:57 AM

Hi, thanks for the reply,

I don't think it is,  I have moved the scope around inside my shed and that image appears to stay there all the time.

It just shows up easier with the grey background.

Wasn't too sure if there was something wrong and i have to send it back.



#4 Stellar1

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Posted 15 August 2020 - 01:15 AM

that's strange, that pattern seems to be too uniform to be anything remotely resembling a smudge of any kind. It looks like a company logo or something, i would shine a flashlight into the front end, down the tube and see if you can spot something. Is that image looking into the front of the scope? that is the strangest thing i have ever run across regarding scope anomalies. 


Edited by Stellar1, 15 August 2020 - 01:15 AM.


#5 bluesilver

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Posted 15 August 2020 - 02:04 AM

That image is looking straight into where the diagonal goes.

Took a bit to get a photo of it.

The scope didn't come with any operation/ instruction manual,  so not sure if i can remove the dew shield or even extend the dew shield to see if that makes any difference.

I should of mentioned earlier it is the Deluxe version,  so it is the Skywatcher Evostar 150 ED Deluxe,  not that that will make any difference.



#6 ASTERON

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Posted 15 August 2020 - 03:01 AM

It seems like there may be something inside the scope tube that reflects light ( sticker maybe) - like stellar1 said, try to shine a flashlight into the front end ( lens) and look inside the tube ( from the same side you are shining the flashlight into) to see if there is something reflective attached to the inside of the tube.

if the tube is just blackened, it may be a region on the inner tube surface where the blackening failed to catch or was masked and remained white.  If there are baffles try to look at them sideways to see if there is anything unusual.

If after all the checks you find nothing  it might be something in the lens coating, consider sending the photo to the seller and/or demand another scope free of problems.

 

BTW, Have you tried using the scope at night to see if the star test is OK ? 



#7 TOMDEY

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Posted 15 August 2020 - 03:04 AM

Almost positive there is nothing wrong with your scope. The two images, identical, radially displaced, different mags, different colorations are simple ghost images of something in the environment. Take your scope and look through it at a neutral wall, from both ends, no Star Diagonal involved. You will notice that the optics are entirely clean. I'm guessing either a corner of your shed window or open door or possibly your camera. This kinda stuff comes under the heading of optical narcissus and optical ghosting.    Tom

 

[I was often called in to do optical imaging forensics. Very few people are into this arcane optical kinda stuff... especially "skilled observers" like pilots, police, astronomers, marine biologists, etc. --- who get comically fooled often, regarding the location and identity of ~bogies~. Most UFOs turn out to be meh optical things; and all the other UFOs are meh other stuff, or hysteria... not Martians.]

Attached Thumbnails

  • 08 ghost examples.jpg


#8 ASTERON

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Posted 15 August 2020 - 03:05 AM

Hi,

I just noticed that the upper left small triangle is very similar to the lower right bigger   triangle, which strengthens the assumption that both may be multiple reflections of the same thing.confused1.gif



#9 TOMDEY

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Posted 15 August 2020 - 03:21 AM

I added some more construction lines (the red ones). Notice that the ghosts radiate from a common ~vanishing point~ at the center of the pupil, and displaced in the off-axis direction of the camera used to document them. Yep --- ghosts --- corner of your shed window or door.    Tom

Attached Thumbnails

  • 09 ghost examples.jpg


#10 bluesilver

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Posted 15 August 2020 - 04:25 AM

Hi,  Appreciate all the advice and information.

I did think the same thing that it was a reflection,  But even rotating the scope around 90 degrees, 180 degrees i still get the same linage.

 

I will try a star test,  not sure yet what to expect from this type of scope as i am use to doing star tests with Dobsonians,  but will have to wait a few days as we are in the middle of stormy weather here for a few days.

 

Will also shine a torch into it tomorrow when it gets daylight again to see if anything odd is going on there.



#11 Asbytec

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Posted 15 August 2020 - 05:03 AM

It shows colors that likely result from the coatings used on the glass. It really appears to be a reflection, and most likely is. As mentioned, if it keeps it's orientation, check inside the scope. If it shows up in the star test, pics please! :)

Edited by Asbytec, 15 August 2020 - 05:06 AM.



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