Strange star flares - Forums

Topic starter

Dec 16, 2023

iv been using my 10" f4 newt for quite sometime now with no hassles, last night i fired it up to image and iv got these odd V-shaped flares. my colimation is slightly off but its never caused odd looking v-shaped flare stars before.

any idears?

andrea tasselli

Frequent contributor

Dec 17, 2023

Something extraneous is in the light path.

James Ross

Dec 17, 2023

Common culprits are the mirror clips although that usually looks symmetrical. If your collimation has slipped far enough (secondary mirror rotation?) it might be making the effect from the clips worse. Focus tube protruding into the light path can also cause something similar but I expect you'd have seen that before now.

If you can't find any obstruction to the light path I'd check for condensation on a coma corrector face if you have one. Warm air rising from the ground or from within the tube is another option - you can easily check this by looking at the orientation of the artefact with respect to the ground, if it is a thermal effect the artefact should usually be pointing vertically up.

Helpful Insightful

Jordan Morley

Topic starter

Dec 17, 2023

spent the afternoon patching up my focuser internal area with sticky flock I remembered that I moved to a new compression ring for my correctors. I believe the colprit may of been the rack slide as it's quite shiny. I cut a 2" circle in a quare piece of flock to hide it. Its worked and I'm back to regular stars in my images! Thanks for the input it helped (:

Jord

Alejandro Navarro

Dec 17, 2023

Hi, you just need an aperture mask
greets!

Jordan Morley

Topic starter

Dec 18, 2023

Alejandro Navarro:
Hi, you just need an aperture mask
greets!

*** iv got one, very important to have on a skywatcher newt***

merrill love

Dec 18, 2023 · Edited: Dec 18, 2023

Is there a smudge near one of the clips? something similar happened to me and the got a closer look and it was when I tried to clean a hair off the primary. It could also be the focuser tube.

Nikola Antonov

Dec 19, 2023

Jordan Morley:
spent the afternoon patching up my focuser internal area with sticky flock I remembered that I moved to a new compression ring for my correctors. I believe the colprit may of been the rack slide as it's quite shiny. I cut a 2" circle in a quare piece of flock to hide it. Its worked and I'm back to regular stars in my images! Thanks for the input it helped (:

Jord

Hi Jordan, could you please explain in more detail what you did and what was the cause of the issue? I think I have the same problem with the same model telescope.

Well Written

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