Switch to mono?

[Bikingbill]

This might seem like a ridiculous question because the answer is going to be yes but...

I've been using a ZWO ASI 533mc with an l-extreme filter for about 18 months now. I'm looking to improve my image quality. Will the switch to mono do this? I would also switch to a larger format like asi2600. Are there any draw backs to mono? Would I see an step up in my image quality? I attach a image I've taken of the Soul Nebula this month.

[Elp]

From that result I'd question why you'd want to change. Changing your post processing will make more difference I think.

Mono does give a slight detail increase, it's very minute, the noise is slightly cleaner (or more fine I think because it doesn't look as blotchy as RGB colour noise as it's in monochrome but it comes back when you RGB composite the layers), technically mono is faster as you're using all pixels (more on this in a bit). The best bit is being able to image in whatever filter bandpass you want, moon being out presents little problem when imaging in ha or S2 (o3 is affected), but the OSC narrowband filters have closed that margin considerably. The data is easier to work with and background extraction in particular works very well with narrowband data.

Mono will be more expensive as you'll need to invest in the filters, even more so if you use fast systems. In terms of speed, this is where it becomes a bit of a grey area, technically on a pixel level you're gathering data quicker than via a Bayer matrix OSC sensor, but I find I usually image one filter per session. So minimum I need three sessions to complete an image (or two if you do a close to RGB HOO composite), it all depends on your expectations on what you want to achieve. I've done complete mono images in 3 hours or less, some 20-30 hours.

[Elp]

If I had less LP, I'd likely do RGB OSC more as you won't capture reflection nebulae in particular in narrowband (you'd do it with LRGB filters in mono). My LP kind of forces me toward mono. Galaxies I tend to use OSC with just a UV/IR or luminance filter, but I have to be mindful of the targets altitude and location in the sky. Mono narrowband I've imaged low altitude and also in the same quadrant as the moon.

[ollypenrice]

That's an exceptionally good Soul nebula. For me its most obvious shortcoming is in star colour, which you could easily catch in a short run without the filter.

Although the 4 pixel array of the Bayer Matrix captures less first hand resolution than mono, the de-bayering algorithms are so good that they restore it. In the real world you will notice no difference.

The advantages of mono are diminished 1) by the CMOS chips because CMOS OSC is, for some reason, far more convincing than CCD OSC. This is based on first hand experience of both. 2) by the arrival of the various NB filters for OSC.

However, mono can be used for fairly moonlit Ha sessions and will allow you to go deeper on faint signal by concentrating on luminance.

Olly

[Bikingbill]

Thank you, these replies have really helped.