[Tamtarn]

Last night I had a good chance to test the GCE filter in light polluted skies.

We normally don't observe in the Western sky glow at all because we have such good skies in every other direction.

The test was done from 10.30pm to Midnight looking west. The target was NGC253 Silver Coin Galaxy which we normally would view in much darker conditions when the galaxy is in the SE or at zenith.

Firstly I used the 27mm Panoptic to find the galaxy. Then used the Pentax 10mm XW ( which has very good contrast already ) with the GCE 1.25" filter and without it. I noticed only a very slight difference with the filter. Using averted vision there was a little more of the galaxy to be seen but nothing very noticeable.

I then put our Meade 15mm QX 1.25" ( which we don't use now because we have our Nagler 17mm T4 ). Without the filter the galaxy was faint and the contrast washed out.

With the filter there was a noticeable difference. More contrast and with averted vision definately more detail appeared showing more of the outer edge of the galaxy more clearly than without the filter.

By testing the filter in the western light polluted glow we realized that this is what the filter is designed for. Using it with the Meade 15mm QX there was a marked difference with the filter because of the added contrast gained and it would be a good all round LPR filter as well for using on other objects.

Because we're lucky enough to have a good site to observe from we hadn't seen a great benefit using the filter with our two Pentax XW's because they already give us great contrast for seeing galaxies in good conditions.

After doing this test we have decided in our situation we have decided that we really don't need this type of filter in our darker sky site. The filter would be very useful in light polluted skies and as the Omega site states the GCE filter rejects the light pollution wavelengths. I found last night that it did the job.

So if anyone in a light polluted site is interested we will be selling our GCE filter on buy and sell ........ or PM us.

Barb