I had another shot at Centaurus A this week. Imaging went ok this time but post processing still has a long way to go. If anyone has the "all you need to know about astrophoto image processing" handbook please post a link here.
Anyway here is my latest attempt to get a reasonable colour image of Centaurus A.
You might want to try: re-registering the RGB frames so you can't see a rainbow fringe or RGB dots instead of single stars. Some gamma scaling to reveal both high-light and shadow detail, also play with the colour balance a tad more..still looks a little too yellow.
I'm not sure how to register to align properly because there appears to be a bit of rotation. I have been re-combining the RGB in PS using Carboni actions so they end up in a single layer (background) in different channels. I've worked out how to shift the individual channels relative to the other two but have not worked out how to rotate one channel. Is this possible?
Also does the histogram reveal whether it is too yellow or is this obvious from how the image appears?
Thanks for the re-work. It looks much better. I'm using PS but can't work out how to rotate a single channel. Anyone know how to do this?
Eric, I'm using the DSI II pro with a Baader UV/IR filter on the front of the CCD. For RGB I'm using the Meade filters that came with the camera in addition to the Baader UV/IR. I'm not aware of an internal filter?
Eric, I'm using the DSI II pro with a Baader UV/IR filter on the front of the CCD. For RGB I'm using the Meade filters that came with the camera in addition to the Baader UV/IR. I'm not aware of an internal filter?
Peter
Peter, there is a standard IR filter in the DSI II. You wouldn't need the Baader UV/IR filter as well. Either take the standard filter out and use the baader one but not both.
The nosepiece can be screwed out and the filter is being held down via a plastic rubber. you unscrew the nosepeice and the filter should just come out. place it somewhere safe then put the baader uv/ir filter in the end of the noisepiece barrel.
Eric. I'm posting two pictures with and without the UV/IR filter attached - If there is another filter it must be inside the housing of my DSI. Is this what yours looks like?
That's the filter im talking about. the standard IR filter. Since you are using the pro version, im not sure if this filter comes standard. Maybe other guys like Ric could tell you if it comes with the IR filter as standard in the pro version. Looking at your images, it doesnt look like you have one.
Hi Peter and Eric, I have the Pro II and filters and the IR filter is standard. That is it in Peters picture, I have swapped mine for an Astronomiks UV/IR. I woudn't worry about using the Meade one and just use the Baader only.
Some of the earlier models had the filter as a glass IR plate covering the chip but the Pro and Pro II changed to a clear glass plate over the chip and the IR filter separate, which meant that any of the Meade RGB filters have to be between the IR filter and the chip.
Peter does this model have the bridge and filter bar?
Thanks for the info. This camera originally had the filter bar but I removed it and the holder (bridge) and replaced it with a ScopeStuff adaptor plate (in the picture). I have a Baader UV/IR filter attached to the ScopeStuff adaptor (LH picture) and the Meade filters in front of this in the filter wheel. I have the Meade IR filter in the wheel with the RGB ones so I can do LRGB without changing the focus.
I didn't realise the CCD chip had a clear glass plate over it - that might explain why I can't blow the dust off. How do you clean dust out if it is between the glass and the CCD?
Hi Peter, I have not experienced dust between the glass and the CCD and I would expect that the only way would be to dismantle the camera again something I have never done.
I can't see how it could get in except from the manufacturer if it has never been opened. Are you sure it's on the CCD and not on one of the filters.
