Reviewer: Don Spain

The Mars filter is a great accessory for enhanced viewing of the Red Planet. I have observed Mars since 1958 in various types and sizes of telescopes. The apparition of 2007-2008 I used mainly a 100mm F/6 achromatic with a 2X Barlow. I used the usual selection of red, orange, yellow, green and blue filters to enhance the view of Mars. With the acquisition of the Orion Mars filter I found that I did not need the others. The albedo marking were much easier to see, the Northern Polar Hood was no problem and in January and February the small Northern Polar Cap became visible. I could see most of the classical marking on Mars with this relative small scope and can honestly say I saw more detail this apparition than at any other of my 50 years of observing the red planet. The filter does introduce a pinkish cast to the disk of the planet, but you will quickly get used to it and enjoy seeing so much on Mars with just a single filter. I highly recommend this filter. Don S. Planetary And Lunar Section Chair, Louisville Astronomical Society

Reviewer: Dennis Stefl

I am pleased with the performance of the Mars filter. It shows more detail and resolution. It is easy to adapt to eyepieces.

Reviewer: Michael Carter

I found the Orion Mars Filter to do a Great job in Enhancing the subtle edges of the dark areas against the red background. The level of Contrast was also improved and allowed for sharper areas of distinction on the smallish red disc. Instead of the white and dark areas blending into the redness of Mars.The edges of these colored areas appeared with a sharper edge of distinction then without the filter. The filter is an asset to Mars Observing and the bigger the scope the bigger the impact. Now it will be interesting to see if this filter will be of any use on either Jupiter or Saturn. Either way I plan on having an Orion Mars Filter ready during the next Mars Opposition. Now if Orion would just carry a 2inch Version of the Filter it would be Awesome!

Reviewer: Don

Tested out my Orion Mars Filter tonight, November 9th, 2007 The atmosphere was really steady, but the transparency was poor. Since Mars is so bright the poor transparency was not a serious factor. All observations were made with a 6 inch, f/8 achromatic refractor. I tested it out on Jupiter a little after sunset. It turned Jupiter to a rather pinkish color. However, it did enhance the belts better than no filter or a blue filter. Started observing Mars around 11:00PM at low power (120X) and no filter. Only a hint of very subtle surface markings and just a suggestion of the North Polar Cap. At 11:30PM added a 2X Barlow to the 10mm Radian eyepiece, making the power 240X. The markings were somewhat better, though the Polar Cap was indistinct. Added a #21 Orange filter, which increased the visibility of the surface markings, but did little for the Polar Cap. Removed the #21 and put in a #80A Blue, which slightly increased the contast of the Polar Cap. Finally I put on the Orion Mars Filter. This made the surface a sort of reddish-pink, but substantially increased the surface marking and the Polar Cap. I could easily identify part of Syrtis Major, Sinus Sabaeus, Sinus Merdian, Hellas, Niliacus Lacus and the small North Polar Cap. I must issue a warning to the inexperienced Martian Observer. These marking are indeed subtle and if you are not used to observing Mars you may not see much of an increase in the performance of your telescope on Mars. However, as you observe Mars more and more you will appreciated this filter...I do recommend it to any serious Mars observer. A side note. After I was done with observing Mars, I dropped down to 120X and observed the Orion Nebula with the Mars filter. It did not change the color of the nebula, but did seem to enhance it somewhat. The stars were pinkish, making the Trapezium a peculiar sight.