This is a really lovely first image. Is this a single exposure or a stack? Does the whole disc fit on the sensor of the 120MM.

I can't help with the Barlow / camera question but maybe try the forum or ask Lyn Smith to put the request in the next Solar Section newsletter.

Hi James,  This is an excellent result for a first image: well done!

Unfortunately I can't help with your Barlow issue: I have the opposite problem with my PST, namely it won't reach focus without a Barlow.

To deal with your Newton's rings, which aren't at all obtrusive, what you should try is flat-fielding the data. The illumination of these solar telescopes is often quite non-uniform, and your image has a rather bright centre which is probably due to that. You can capture a flat-field AVI with a piece of diffusing material over the front of the telescope. Materials like tracing paper or greaseproof paper generally make the field too dim; I use a piece of textured plastic cut from an A4 document sleeve which seems to work pretty well. It's best to aim the telescope at the centre of the Sun while acquiring the data. There is a Create Flat-field option in Registax (under the Flat/Dark/Reference tab at the top) which simply stacks all the frames, then you can save the result and use it when processing your solar data.

Good luck.

Chris