Field Flattener f/5 to f/7 92-series-eyepieces 25" H-Beta Range from 478nm

25" H-Beta Range from 478nm to 496nm with peak at 489nm

Meets the Transmission Requirements of AS/NZS 1338

(Notified Body No

the National Geographic 300x-1200x Microscope offers powerful tools to examine specimens in detail

EMD-coated optics

Field Flattener f/5 to f/7 92-series-eyepieces 25" H-Beta Range from 478nmWhen doing astrophotography with refractor type telescopes, the faster the focal ratio the more field curvature becomes a problem. Field curvature will appear in the corners of astrophotographs, making the stars smear perpendicular to the axis of the image. This is called coma coma is Latin for comet, because the stars look like comets. The more the curvature, the closer to the center the coma appears. The larger the sensor, the worse the coma.