Filter wheels are an essential component of any astrophotography setup. They allow you to quickly and easily change between different filters without having to manually switch them out. However, when installing unmounted filters onto a filter wheel, it can be tricky to know which side is the correct one to face towards the camera or telescope. In this article, we’ll explain how to determine the correct side of an unmounted filter when installing it onto a filter wheel.
Step 1: Check the Filter’s Coating
The first step to determine the correct side of an unmounted filter is to check its coating. Most filters are coated with an anti-reflection material on one side, and this is the side that should face towards the camera or telescope. The coating helps to reduce glare and reflections, which can cause unwanted artifacts in your astrophotography images.
Step 2: Look for a Label
Some unmounted filters may have a label on one side indicating which side should face towards the camera or telescope. Look for any markings or text on the filter that might give you a clue as to which side is the correct one. If there are no markings, move on to the next step.
Step 3: Perform a Test
If you’re still unsure which side is the correct one, you can perform a simple test. Hold the filter up to a bright light source, such as a flashlight or lamp, and look through it from both sides. The side that appears to have less glare and reflections is the side that should face towards the camera or telescope. If you’re still not sure, try rotating the filter and repeating the test to see if one side consistently appears to have less glare than the other.
Step 4: Mark the Correct Side
Once you’ve determined which side of the filter is the correct one, it’s a good idea to mark it so that you don’t accidentally install it the wrong way around in the future. You can use a permanent marker or a small sticker to indicate which side should face towards the camera or telescope.
In conclusion, determining the correct side of an unmounted filter when installing it onto a filter wheel is an important step in achieving high-quality astrophotography images. By following the steps outlined in this article, you should be able to easily determine which side of the filter is the correct one and avoid any unwanted artifacts in your images.