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hobsey

Full Spectrum mod for widefield

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I'm still undecided which mod to go for.

I will only be using the camera with camera lenses and will not be using it for normal as I have another camera for this.

Is it worth getting a full spectrum mod if I only intend to do widefield?

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I assume we're talking about the 1100D

Removing the colour correction filter at the CCD chip will greatly enhance the red response. Nebula etc will be much better recorded.

To maintain the use (focus) of the standard camera lenses you need to replace the filter with a suitable clear or UV/IR filter.

(A FULL full spectrum mod usually infers both the colour correcting and the front anti-alias/ dust filter are removed.

OK for spectroscopy, but again needs replacement UV/IR filters for AP work)

Hope this helps.

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I assume we're talking about the 1100D

We are, sorry I should have said.

That is a great help, thank you.

Astronomiser charges the same for both the filter removal and full spectrum mod so I was just wondering if it was worth it.

Can I just ask, what is the point of having it modified if you are going to put a UV/IR filter back on? or would that just be for normal photography and use a clear one for astro?

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The filter removed is a colour balancing filter and supresses red light.

It also has a UV/IR cut effect.

The front dust filter also acts as a UV/IR cut, but some AP users have indicated with long exposures there can be some leakage.

So, to minimise star "bloat" and IR halos the colour balance filter is usually replaced with a UV/IR filter. This also retains the focus on standard lenses.

The UV/IR filter has no effect on the red colour response.....

HTH

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Right, gotcha.

So would a clip in uv/ir filter be ok to use?

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Thank you very much for your help.

I will be going full spectrum with a clip in uv/ir filter then.

Thanks again.

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There probably isn't any advantage to getting a full-spectrum mod for widefield. I had one done on mine because I wanted the option of imaging in IR. But that needs an IR pass filter which I haven't acquired yet. Hutech do a hard to get hold of BGR filter set which facilitate imaging in different IR bands. If only the skies were always clear and I had unlimited funds...

Louise

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Thank you very much for your help.

I will be going full spectrum with a clip in uv/ir filter then.

Thanks again.

If youre going for the clip in, just remember that it will limit your choice of lens.

EF will work EF-S wont.

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That's cool, I knew that.

Don't think I have any ef-s lens I intend to use anyway.

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