H beta and O III filter by software

[elpajare]

Would it be possible to imitate these filters by software?

May be possible to create a pattern of light that reproduces them by eliminating unnecessary colors by software.

Could it be very interesting to also create a filter for the light of the moon or street lamps by this method?

This will be very interesting for EAA and a very important complement for the Infinity.

[Chris]

No you can't reproduce the effect of narrow band filters with software.  The filters built into the colour CCDs are far too wide to be able to do this.

Chris

[elpajare]

Thanks for the reply, Chris.

When using Saturation bar ( Orange) I can modify and quite eliminate the yellowish tone of the moonlight or the orange of the street lights by lowering the RED channel tone.

Could it be done automatically by creating user-selectable previous filters?

[bwa]

You can split any color image to red, green and blue.  You can then approximate a narrowband image by assigning Ha to Red, Oiii to Green and Sii to Blue, or any combination you want, such as the Hubble palette.  Poor man's narrowbanding!

[elpajare]

Thanks BWA.

Filters use is a taboo in astronomy. Anyone doubts in his efficiency

My experience with this is no so good, a lot of light is lost and for EAA light is essential.

I think too that assigning different values to the RGB channels we can improve and minimize light pollution effects and make satisfactorily approaching a HII narrowband filters.

My question was if Attik can make this combinations for us and create a pattern to have a good approach by clicking a button to do:

Moon light pollution

Orange street light pollution

Approach to H II narrowband

Minimize chromatism in cheap refractors


etc...

[Chris]

The point with narrow band filters is that they let through almost all of the light that you want while eliminating the light that you don't want.  If you want Ha that's what you get and nothing else, if OIII then that's all you get.  Broad band filters don't do this and no amount of belief will change this.

Chris R

[JimH123]

I think a point is being missed here in the way OSC vs mono CCD cameras work.

If you are using OSC, the use of filters is questionable.  For instance, in using an HA type filter, only 1/4 of the pixels (red) will record anything and 3/4 of the pixels (Blue and Green) record noise.

With a mono CCD, all pixels record, no matter what filter is being used.  And then the results from the separate filters can be combined into a composite image with far better results.

OSC is used when you are looking for an easy way to capture.  Mono is used when you want the best capture.

I use OSC when I do youth groups where they have no patience for capturing separate colors and combining.  Certainly the mono results would be better, but in this case, quick results are what is needed.

[elpajare]

Jim, I'm agree with you. Thanks for your clear explanation.

I have a color camera I do video astronomy and I verified there was not improvement using filters. On the contrary, there was less detail and less light.

We will leave the filters for the mono cameras.