Imaging Help

[eliot]

Help!

I have been trying to do some Ha imaging with a PST + QHY5v (mono), and to be quite frank my results are rubbish. The camera will go either side of focus but getting accurate focus seems to be impossible.

With the QHY5v on its minimum exposure settings the disk surface is over exposed, but I can get pick out some prominences. I used a #56 Wratton Filter to reduce the amount of light, but it made the camera nose piece is too long and pushed the camera out of the focus range of the telescope.

I realise that my unmodified PST only has a 40mm objective and I won't get the same performance as a larger scope. It really frustrates me that I can't image anywhere near as well as what I can see visually. I'm sure that it is user error and not the equipment.

Does anyone have tips for getting focus? Even though it is a Ha scope do I need to use an IR/UV cut filter to help focus? If so why?

I’ll get a shorter nose piece so I can add filters to reduce the amount of light on the chip. Should I stick with the #56 Wratton or get a neutral density filter?

[markt]

Get a shorter nosepeice and use a neutral density filter...

[JamieW]

Hi Eliot, I use a QHY5 mono which is similar to yours and use QGVideo capturing at ~7ms with the gain at zero. It also helps a lot to have as much shade as possible to be able to pick out the detail on your monitor. HTH.

[eliot]

Thanks Guys,

Hmmm. Shade could be my issue. I was sitting in side the Patio doors in the shade of the house with the PST outside. However that probably wasn't enough I'll try putting the laptop in a cardboard box next time.

I'll also get a neutral density filter and a stubby nose piece.

[eliot]

Quick update.

I've finally managed to get the PST and my QHY5v working. I found that even a stubby nose piece pushed the camera away from the maximum focus point. In the end I had to screw in a 0.3 and 0.6 ND filters directly into the camera. And then tighten the PST thumb screw to them.

The image below is my first attempt with this set up from the 26th May.

2012-05-26 (2) - Sun PST Ha.tif

[PeterW]

There you go... nice image!!

PeterW

[tjensen]

Hi Eliot,

Nice image. Glad you got the issues worked out. I use a big box that I i stick my computer, and head, into while imaging. I had to make a short nose piece to get my camera (Flea3) to focus on the PST.

Good luck with the transit.

Cheers