Advice please

[sterec]

Recently I have started to notice some kind of aberration when I look through the eyepiece and on the images.

I enclose a sample but would be grateful for any advice on how to eradicate it rather than remove it in photoshop.

It is the circular arcs of light coming from the peripheral stars in the image.

[Thalestris24]

Hi

I can see what you mean but would need info on your equipment including camera, field flattener and any filters used. If the reflections move as the mount tracks the reflections should disappear with kappa-sigma stacking.

Do you have a dew shield / lens hood?

Louise

 

[sterec]

Louise

Thank you for your interest.  The telescope is a Celestron 6SE and I have attached a Nikon DSLR to capture the problem.  As I slew the size of the reflection changes and disappears when the object gets into the centre of the field.  I have used a field reducer sometimes and this makes no difference and the aberration is present right at the beginning and doesn't change in magnitude throughout the session.  I have made a dew shield and I am positive that there is no dew or other smears on the front of the telescope at the end of the session.  

I look forward to any further ideas you may have.

Stephen

[Thalestris24]

Hi

I asked about the dew shield since it can help prevent picking up external light sources such as street lights etc. It's most likely an internal reflection. The problem of halo loops/rings with some sct's has been reported before. Looks like flocking may solve it though the precise cause seems unclear.

[sterec]

Once again thank  you, all rather frustrating.  May have to tolerate it since my concern is disassembling the telescope tube may create more problems than it solves!

[happy-kat]

Could take a read of this thread. There are some great images shared before and after.

Link here

[Thalestris24]

From CN:

"After following this thread, and a couple of others, I decided to check my C6 on Jupiter and Vega last night.
Holy *bleep*...a terrible flare/ring when the bright target was moved off axis. I changed eyepieces and diagonal, as someone suggested, with no change. I then inspected the main baffle with a flashlight and found that the first inch or so (corrector end) had what looked like high gloss paint or shiny glue smeared on it. 
Tonight, I took the corrector off (marked it first, of course) and lined the shiny portion in the baffle with black felt.
I then took it out for another test...
  
No more flare/ring and the background seemed to be darker.
A definite improvement!!
This is one nice little scope and is an absolute joy to use on my Vixen PortaMount.
Thanks to all for contributing to this thread and bringing the (possible) problem to my attention. " 

[sterec]

Thank you for doing all this research on my behalf.  Will therefore address the problem since there is a definite answer.

Once again many thanks.