Yep...have used those too and they are okay for imaging, but your exposures will have to increase to make up for the blocking capacity of the filter itself.
Now, that being said, and after looking at the fine images from Cloudy Nights (warning:  never, ever believe everything that you read on Cloudy Nights.....), you reallly cannot judge the improvement of the filter use because NO photo without the filter is presented to compare to.  That is the only way to judge:  1) loss of sky contrast; 2) loss of magnitude or brightness; 3) loss of contrast.

That being said, this particularly filter is pretty good, as good as any.  But you still will lose some contrast and brightness by its use.....again no such thing as somewith without giving up something else.

Doc

I actually did an independent testing on this filter for a publication; there are advantages and disadvantages.....the main drawback is the loss of light which is actually more significant than I would have thought with no more blocking across the spectrum than this filter does.  Also it will not work well at all for imaging, producing false reflections and distortions, again something that I was rather disappointed in.

In filters, you never get something for nothing and there are always tradeoffs.  For blocking lunar glare, it does work, but you lose about a magnitude of star limiting mag. with it and there is a very un-natural contrast between sky and object on deep sky objects such as bright nebulae and galaxies.

As conditions grow worse in and around cities these filters are filling the marketplace, but they simply do not work as advertised.  I would put the money back and use it for gas to a dark sky site where the filter would not be needed if I had to make the choice.

Doc

Indeed....if the general public does not like what they see or hear, they will strive to make up what makes them happy.
And the media is typically all-to-happy to oblige; after all, ratings is the most important factor, not accuracy.

Doc

COMETS OF 2013:  Filtering through Fact vs. Hype

There is much starting to appear in "the press" concerning the upcoming
appearances of Comets 2011 L4 (PanStarrs) and 2012 S1 ISON.  Thus far there has
been no glaring suggestion that we are in any danger from these two objects, but
as time grows near (PanStarrs in March and ISON in December, 2013) we can rest
assured that there will be some "cult attraction to the possible human influence
of these two celestial visitors.

Recently, professional comet astronomers have been discussing just this point
and how to approach the dissemination of useful and meaningful information about
the comet to the public; after all, these two objects should be something of a
showcase event, with curving tails and ISON even possibly visible during
daylight hours.  Sometimes "getting out" information results in
misinterpretations particularly when it involves comets....it has been this way
since ancient times when comets were seen as precursors of doom, disease,
droughts and famines.

In 1972 the now infamous comet Kohoutek was inbound toward Earth and its
encounter with the sun, and since it was discovered at so great a distance and
appeared so bright in that early part of its path, it had been erroneously
predicted to be "The Comet of the Century" by some astronomers and some
predictions put the brightness and size of this orb into full tilt mode; the
result was predictions of doom and gloom for Earthlings and thus began the 20th
century comet cult, culminating in the mass suicides of dozens of people by the
time that Comet Hale-Bopp entered out skies in 1995.

I have been in the "comet business" for 48 years and have seen the great ones of
the 20th century come and go and those not-so-great that were anticipated to be
great fizzle in front of high expectations of both scientists and the general
public.

The public, we have to understand, "wants" things like bright comets.  It is a
wonderful alternative to what has become mundane in society; they want something
different, and they want something exciting and even "dangerous" (i.e., the
hazards of Cyanide gas in Halley's of 1910).  It makes life exciting and more
appreciable.

I can tell you from experience writing for both AP and UPI and several public
science magazines for decades that no matter WHAT you give the public, it is
going to be altered or misconstrued into what their appetites crave.  An
incredibly accurate example was comet Hale-Bopp which was safely covered in
terms of press from the astronomy community, only one decade after the Kohoutek
frenzy.  One report of something spotted with similar proper motion in the wake
of the comet was enough to set of the type of temporary hysteria that we are all
familiar with.  We have good "press" and we have very bad press and readers will
always choose to read the edition that is going to satisfy their craving for the
spice of excitement if they are in that mind-frame.

Getting the "correct information" out to the press is of course a good idea and
I think that is what we all strive to do.  What "The Press" decides to do with
that information after it is disseminated is entirely out of our hands.

By the time that ISON makes its way into northern skies after late November,
comet hysteria will be back in the dark ages once again for a great percentage
of the public.

It is not that we are dealing with an uneducated public, it is that they are
choosing the form of education that they get.
Did you know that the "Dying Queen" has already enthroned William as King of
England?  It is true....I saw it at the checkout line at the grocery store.  It
was printed, so it must be true.

Good luck to you all keeping your local areas informed.  Should be a fun year!

Clay
_____
Dr. P. Clay Sherrod
Arkansas Sky Observatories
MPC H45 - Petit Jean Mountain South
MPC H41 - Petit Jean Mountain
MPC H43 - Conway West
http://www.arksky.org/

Congrats on a prosperous Christmas to you gentlemen and a very Happy New Year.

Doc

Just wait until next fall (2013) when Comet Ison starts getting TV and newspaper fanfare....you will not be able to FIND a telescope in stock anywhere in the world....then, the next three months you will be able to buy a "low mileage" scope fokr next to nothing.  This happened with Comet Kohoutek in 1973 and later with Halley's Comet in 1985-86.

So, if you want a wide field telescope, now is the time to buy it.  Otherwise wait until 2014 and beyond because they will not be found.

Doc

See?  It works....
Today we have freezing rain, sleet and heavy snow forecast.
High Tech:  Native American Style.

Doc

I have watched this phenomenon over the years and indeed it is very, very accurate.  Fun to keep up with too!

Everyone have a wonderful Christmas!

Doc

Off the topic of the photographic aspect, there is an interesting and accurate story that the Native Americans would look for the circle around the moon; when seen, you count the number of bright stars visible within the ring and that is the number of days until rain or snow.

Interestingly this is meteorologically correct:  the high ice crytals in stratospheric clouds will reflect moonlight that is passing through them and many times refract it into the circle that you see; the higher the ice crystals the larger the ring, and the farther the front that is bringing rain or typically more often snow....thus more stars visible within a larger ring; as the front gets close, the ice layer that the moonlight passes through sinks closer to the ground and narrows up the ring for your line of sight, and the number of bright stars diminishes, and hence less days until snowfall.

If you ever have the combination of winter cold front and a full moon....try this as an experiment.  Bet it works to within one day every time.

Doc

What a wonderful greeting card for ASO....much thanks both Dave and Ron.
Have a wonderful holiday and may bright comets reward you in 2013!

Doc

Yes....so much for "Free Trade"....remember that agreement?
I deal with this every day with astronomy equipment and it is a travesty; not only is it difficult and lengthy to get things across, but costly too.  The tariffs and taxes are horrible and applied for no reason and without any guidelines whatsoever.

Also, in terms of astro equipment, all the big manufacturers have set up exclusive dealerships with folks in Cananda with the agreement that NO U.S. dealer can sell to you direct or they are in violation with their contract with these "Made in China" companies.  You have to buy from a Canadian dealer or put another dealer out of business.

The way around it is to have a relative or friend buy for you in the US and then send to you as a gift.

Don't you love our politicians and fat cat representatives who are getting rich off of making life hard for us all?

Doc

Not getting too many encouraging reports thus far on the Geminid shower.  A few at best per hour being reported, some higher numbers in random clusters it appears.
Hopefully we will hear from a few others on this.  Thanks for the reports.

Doc

Well, you had better hurry up.....the world ends, rememer, in only 7 days.
I am working on my bucket list this week but still cannot decide between the Gray or the Red Ferrari.

Congrats and thanks for being our "century lurker" and always keeping me up to date on issues that need to be addressed!

Doc

GEMINID METEORS PEAK DECEMBER 13 !! 100 per hour possible this year....
The title says it all.....
Be sure and mark Thursday night-Friday morning on your calendars when the clear and moonless (yes, a NEW moon this year) night may yield as many as 100 bright Geminid meteors per hour after 11 p.m. local time and into the following morning dark hours.

The later you stay up, the more that you will be rewarded and this year is particularly favored for this meteor shower (See December Sky Events Calendar for details).

Dr. Clay

They also appear often which may suggest that they are not as optimum for some equipment as the ads might imply.
They really require a huge amount of back focus too, so keep that in mind.
But, I think the big rule is simple:  if the price is cheap, so is the product......when it comes to binoviewers.

Also remember that you will need TWO of each set of eyepieces for varying powers and those eyepieces need to be very closely matched and fairly high end to be parfocal.

Costs run up quickly, as does weight and loss of back focus.

Doc