Filter Questions for Modded DSLR

[Michael Keo]

Hi,

im looking into getting a  light pollution filter for my modded 100D,

ive read some things on here saying that I’m best going for a UHC clip in filter and then others advising getting a CLS CCD filter?

also says that I want one with an IR cut?

The IR cut one confuses me though because why have a modded a camera to then get a clip in filter that cuts the IR again?

 

Thanks in advance for clearing it up for me!!

[wormix]

Following, as I have the exact same questions!

[ollypenrice]

6 minutes ago, Michael Keo said:

Hi,

 

The IR cut one confuses me though because why have a modded a camera to then get a clip in filter that cuts the IR again?

 

Thanks in advance for clearing it up for me!!

Ha is well short of IR. Ha is around 656nm and IR begins at 700nm.

Olly

[bobro]

Refractor telescopes bend light depending on wavelength. IR wavelengths can result in slightly out of focus images with refractors, hence the need for IR cut filters. Reflectors don't have this issue, hence an IR cut filter isn't so necessary to stop this.

A CLS filter attempts to cut light wavelengths from local light pollution, so can be used for imaging galaxies where colour reproduction is important.

UHC filters (not all are the same)  limit wavelengths to the blue and red part of the spectrum. This is good for imaging emission nebulae as these produce mainly red and blue wavelengths, but not so good for galaxies where the wider wavelengths/colours are not passed.

Hope this helps.

[Michael Keo]

51 minutes ago, bobro said:

Refractor telescopes bend light depending on wavelength. IR wavelengths can result in slightly out of focus images with refractors, hence the need for IR cut filters. Reflectors don't have this issue, hence an IR cut filter isn't so necessary to stop this.

A CLS filter attempts to cut light wavelengths from local light pollution, so can be used for imaging galaxies where colour reproduction is important.

UHC filters (not all are the same)  limit wavelengths to the blue and red part of the spectrum. This is good for imaging emission nebulae as these produce mainly red and blue wavelengths, but not so good for galaxies where the wider wavelengths/colours are not passed.

Hope this helps.

Cheers.

at the moment I’m using a 50mm lens and I’ve got a 200mm Takumar Pentax lens so I don’t really know if I could get any decent galaxy’s at that focal length so I think I’ll go for a CLS?

I do have a 150pl reflector but I only have to look at it on my eq3-2 mount and it starts wobbling ha.