For the use in front of a CCD- camera we offer you the Astronomik IR- cut off filter. CCD sensors are very sensitive not only in the visual spectral range, but even far into the infrared. On pictures, taken without IR- cut off filter, some objects look totally different, as one knows them from photographs or from visual observation. The IR- radiation produces at all optical systems, where lenses are (also) used for the image (also at eyepiece projection, Barlow- and Shapley- lenses), a more or less big glare around the image of the visual light. You will see this glare also at the best apochromats, if they are not specially calculated for CCD use. The glare will disappear by using an IR- cut off filter in front of the chip.
The Astronomik IR- cut off filter can be used at all focal ratios. It will produce its full performance also at a 1:1.2 photo lens as well as with a 1:20 refractor. Because the glass substrate has a very high optical quality, the use in front of the lens without any loss in the image performance is possible. Due to the extreme robust coats the filter can be used as a protection of sensitive optics.
One word concerning the comparison with other IR- cut off filters: You can get IR- cut off filters from many different manufactures for very different prizes. Please, compare the transmission values and ask for information on the optical quality and about the mechanical capacity. We regularly receive from customers, who made these comparison, the response, that the Astronomik IR- cut off filter is worldwide the best IR- filter.
Transmission of more than 97% in the visual range.
Extrem steep cuttoff at 675nm.
Full H-alpha (656nm) transmission.
IR-blocking up to 1200nm.
Completly resistant against high humidity and scratches.
Highest optical quality on the market.
Please, ask for availability before placing your order. Thank you in advance.