fine horizontal lines when using ASI cameras with LS80 -help

jeffp

I got a LS80 and am trying to use my ASI174MM and ASI120MM-S

I haven't had that much time to play with the LS80 yet, it has been in the low 20's and winds 20-30 mph, if it is cloudy it is warm and no wind, clear cold and windy!!

Anyhow i threw a Meade shorty 3x Barlow on the B1800 with the ASI 174mm I get NR but they are large, I had 5 on this shot, but what bothers me is the very fine lines, almost like I printed it on textured paper or it was the noise pattern on a TV

Some said it is a Bayer Matrix but it is a mono camera. You cannot see the lines until you process the AVI

Since it is on both camera's I can't see how it is the cameras, I used the same cable on them, could it be the cable that ZWO provides with the camera, but they have been working well with other HA scopes

for examples of the good captures see https://www.flickr.com/photos/jmpadell/

https://www.flickr.com/photos/jmpadell/

Sam@ZWO

sorry, seems I cannot see it in your image

@solarastronomer

Hey Jeff, I might be able to offer a bit of insight here as I have they same setup, exactly. I'm not sure if you're on Instagram but all (save for a couple of Quark shots) of my Hα images here https://www.instagram.com/solarastronomer/ were taken with the LS80 and 174MM. Additionally, the closeups are using an Explore Scientific 3X, so we really are doing very close to the same thing here.

The issue you're having with Newton rings is very common when you bring these semi-reflective surfaces close together. '>https://en.wikipedia.org/wiki/Newton's_rings

Here's the weird bit. . . it seems no two LS80/174MM combinations are the same, some people are affected more than others. I don't, and never have had any problems with this when using only my 174 and B1800, full disk stuff. I DO however get the identical dark bands when using the 3X. I process them out using flats and Photoshop, this is a good thread on the topic. https://solarchatforum.com/viewtopic.php?f=4&t=2590 There's also a mechanical method to mitigate the effect. Using a tilt adapter, you can disrupt the interference pattern slightly and usually correct the majority of it. https://astronomy-imaging-camera.com/products/accessories/t2-tilter/

Those are pretty much the only options for fixing something that we all have to deal with in some way.

This is the sticky about it from this forum http://zwoug.org/viewtopic.php?f=21&t=1408

merlin66

I'm also using the ASI 174MM on a spectroheliograph and Ha solar applications.....

Yes, there are Newton Rings.....

I've just ordered a tilter from ZWO

Hopefully that will resolve the problem.