Light Pollution Filters

Greets,

I am in a large So. California suburb area where light pollution
rules. It's probably not as bad as Washington DC but you can rarely
see the Milky Way around here. Last night, I could't even see the M42
nebula, though this was more due to the moon than city lights.

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Anyone in the So. Cal metropolis using one of these filters? There
are H-Beta, O-III, broad band, narrow band, and I'm sure more. $100
would pay for several trips to the desert, but if these filters are
really effective, then I'd be all for it.

Thanks,
Matt

"MW" wrote in message
om...
Greets,

I am in a large So. California suburb area where light pollution
rules. It's probably not as bad as Washington DC but you can rarely
see the Milky Way around here. Last night, I could't even see the M42
nebula, though this was more due to the moon than city lights.

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Anyone in the So. Cal metropolis using one of these filters? There
are H-Beta, O-III, broad band, narrow band, and I'm sure more. $100
would pay for several trips to the desert, but if these filters are
really effective, then I'd be all for it.

Thanks,
Matt
The first two filters, are not 'light pollution' filters as such. These are
narrow band filters, letting through one part of the spectrum only. The
rejection of human light pollution by these is a 'side effect' of their
narrow band pass (though a good one). They are only useful, if you want to
look at objects that radiate on the specific band.
Most 'LPR' filters, work the other way, and are typically 'band cut'
filters, designed to reject a number of fairly specific light colours.
Normally, the main lines from mercury vapour, and the high/low pressure
sodium lights. Some are quite effective at reducing the effect of these
lights.
The 'narrow band'/'wide band', then refers normally to the widths of the
actual pass/block bands involved. Narrow band filters generally have a
'better' effect, but at the cost of throwing away some light that may be
useable.
LPR filters, will not reduce the light from car headlights, and household
incandescent lights significantly, but fortunately, these are often
relatively small contributors to 'skyglow'.
The Lumicon UHC, and the Orion 'Ultrablocks', both work quite effectively,
in reducing the effects of street lamps in particular.
Most photographic filters, are just coloured glass, when these filters use
interference coatings to give the narrow bands involved.
A 'trip to the desert', will _allways_ be more effective than the filters.

Best Wishes

"MW" wrote in message
om...
Greets,

I am in a large So. California suburb area where light pollution
rules. It's probably not as bad as Washington DC but you can rarely
see the Milky Way around here. Last night, I could't even see the M42
nebula, though this was more due to the moon than city lights.

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Anyone in the So. Cal metropolis using one of these filters? There
are H-Beta, O-III, broad band, narrow band, and I'm sure more. $100
would pay for several trips to the desert, but if these filters are
really effective, then I'd be all for it.

Thanks,
Matt
The first two filters, are not 'light pollution' filters as such. These are
narrow band filters, letting through one part of the spectrum only. The
rejection of human light pollution by these is a 'side effect' of their
narrow band pass (though a good one). They are only useful, if you want to
look at objects that radiate on the specific band.
Most 'LPR' filters, work the other way, and are typically 'band cut'
filters, designed to reject a number of fairly specific light colours.
Normally, the main lines from mercury vapour, and the high/low pressure
sodium lights. Some are quite effective at reducing the effect of these
lights.
The 'narrow band'/'wide band', then refers normally to the widths of the
actual pass/block bands involved. Narrow band filters generally have a
'better' effect, but at the cost of throwing away some light that may be
useable.
LPR filters, will not reduce the light from car headlights, and household
incandescent lights significantly, but fortunately, these are often
relatively small contributors to 'skyglow'.
The Lumicon UHC, and the Orion 'Ultrablocks', both work quite effectively,
in reducing the effects of street lamps in particular.
Most photographic filters, are just coloured glass, when these filters use
interference coatings to give the narrow bands involved.
A 'trip to the desert', will _allways_ be more effective than the filters.

Best Wishes

"MW" wrote in message
om...
Greets,

I am in a large So. California suburb area where light pollution
rules. It's probably not as bad as Washington DC but you can rarely
see the Milky Way around here. Last night, I could't even see the M42
nebula, though this was more due to the moon than city lights.

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Anyone in the So. Cal metropolis using one of these filters? There
are H-Beta, O-III, broad band, narrow band, and I'm sure more. $100
would pay for several trips to the desert, but if these filters are
really effective, then I'd be all for it.

Thanks,
Matt
The first two filters, are not 'light pollution' filters as such. These are
narrow band filters, letting through one part of the spectrum only. The
rejection of human light pollution by these is a 'side effect' of their
narrow band pass (though a good one). They are only useful, if you want to
look at objects that radiate on the specific band.
Most 'LPR' filters, work the other way, and are typically 'band cut'
filters, designed to reject a number of fairly specific light colours.
Normally, the main lines from mercury vapour, and the high/low pressure
sodium lights. Some are quite effective at reducing the effect of these
lights.
The 'narrow band'/'wide band', then refers normally to the widths of the
actual pass/block bands involved. Narrow band filters generally have a
'better' effect, but at the cost of throwing away some light that may be
useable.
LPR filters, will not reduce the light from car headlights, and household
incandescent lights significantly, but fortunately, these are often
relatively small contributors to 'skyglow'.
The Lumicon UHC, and the Orion 'Ultrablocks', both work quite effectively,
in reducing the effects of street lamps in particular.
Most photographic filters, are just coloured glass, when these filters use
interference coatings to give the narrow bands involved.
A 'trip to the desert', will _allways_ be more effective than the filters.

Best Wishes

MW wrote:

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Michael A. Covington writes of at least one filter you may already have:

http://www.covingtoninnovations.com/....html#didymium

He also mentions another on the same page: IDAS (formerly Tokai) Light
Pollution Suppression Filter

I found a didymium on ebay for very little money a few weeks ago, I
might have my own report on it's abilities but unfortunately it doesn't
filter rain and clouds. As for telescopic use, I've been happy with my
celestron filter, but no filter is like a trip to the desert! Be glad
you're so fairly close, I travel 2500 miles to get there.

Clear Skies,
Rudie

MW wrote:

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Michael A. Covington writes of at least one filter you may already have:

http://www.covingtoninnovations.com/....html#didymium

He also mentions another on the same page: IDAS (formerly Tokai) Light
Pollution Suppression Filter

I found a didymium on ebay for very little money a few weeks ago, I
might have my own report on it's abilities but unfortunately it doesn't
filter rain and clouds. As for telescopic use, I've been happy with my
celestron filter, but no filter is like a trip to the desert! Be glad
you're so fairly close, I travel 2500 miles to get there.

Clear Skies,
Rudie

MW wrote:

Will these light pollution filters make a huge difference? These
things cost from $60-100, so it's one purchase of a piece of glass
that I can't take lightly. As a photographer, I have a passel of
filters. Are there any that might perform the work of a light
pollution filter to an extent? IOW, I would rather use something I
already have rather than buy a glorified skylight ;-)

Michael A. Covington writes of at least one filter you may already have:

http://www.covingtoninnovations.com/....html#didymium

He also mentions another on the same page: IDAS (formerly Tokai) Light
Pollution Suppression Filter

I found a didymium on ebay for very little money a few weeks ago, I
might have my own report on it's abilities but unfortunately it doesn't
filter rain and clouds. As for telescopic use, I've been happy with my
celestron filter, but no filter is like a trip to the desert! Be glad
you're so fairly close, I travel 2500 miles to get there.

Clear Skies,
Rudie

A didymium glass "color enhancer" ("Tiffen color enhancer") will work like a
weak broadband nebula filter and will give you some idea of what to expect.

A didymium glass "color enhancer" ("Tiffen color enhancer") will work like a
weak broadband nebula filter and will give you some idea of what to expect.

A didymium glass "color enhancer" ("Tiffen color enhancer") will work like a
weak broadband nebula filter and will give you some idea of what to expect.