Strange Wipe Behaviour

[Davo]

I just came back to deep sky work after a few years. I tried my usual workflow of Autodev>Wipe> etc on some DSS fits and got results like shown in the attached screenshot. Images were shot on a Canon 1100D with a 300mm lens at f11 and iso 1600, 11 shots at 180s each. The camera was guided with PHD2 so I don't think it was a tracking artefact. Any ideas on what is causing the letterboxing effect which I have never seen before?

[admin]

It bears all the hallmarks of stacking artifacts. I think I can indeed see some near the borders. Zoom into the edges and see if you can see any. Cropping a couple of pixels and trying Wipe again, will also help determine whether you are dealing with stacking artifacts.

[Davo]

It bears all the hallmarks of stacking artifacts. I think I can indeed see some near the borders. Zoom into the edges and see if you can see any. Cropping a couple of pixels and trying Wipe again, will also help determine whether you are dealing with stacking artifacts.

Great call, Ivo. I cropped 50 pixels all round and StarTools is now working as it used to. I should have read the artifacts warning that came up when I loaded the image. My workflow is now Load>Crop>Autodev>Wipe>etc...

Changes since I last used ST is that I now have a guide camera, new primary lens and the 64bit version of DSS. Maybe one of these upset my workflow? Anyhoos, problem solved

Many thanks
Dave

[admin]

Good to hear! Congrats on the guidecam and primary - hoping you're getting plenty of clear skies!