Coatings are professionally applied in Germany by the most sophisticated equipment available today, ensuring high consistency for bandpass cutoffs, transmission, and out of band blocking. The anti-reflection coatings are evenly balanced on both sides of the filters to reduce surface stresses and prevent deformation of the substrates. The ultra-hard ionbeam deposition ensures the coatings will never degrade from use or normal cleaning. Unlike many competing filters Baader coats each filter individually. Though more costly, this process avoids the coating failures that can result when filters are mass produced.
Through an extensive coating stack design and testing program, Baader has partnered with the world's leading thin film coating company to produce the unique transmission curves. Their ultra steep cutoffs and high transmission (95%) allowed Baader to do something to a degree no other RGB filter set can manage - they are able to effectively separate the important H-Beta and O-III lines. The Baader Blue filter passes virtually all of the H-Beta and O-III lines, while the Green filter is able to capture all of the O-III line, without encroaching into the H-Beta line. None of the light is wasted by either filter so the O-III is represented as it should be, a teal (blue-green) colour, and H-Beta is captured solely in the blue. Never before has this degree of separation been achieved, and with such high transmission of both lines.
In addition, the Green and Red filter passbands nearly touch, leaving only a sharp notch to block out the primary Mercury/Sodium light pollution line at 580nm. The high transmission everywhere else delivers the shortest combined exposures possible.
In addition to their special transmission properties, the Baader coatings were developed with another key goal in mind to eliminate reflections. To achieve this freedom from reflections required careful balancing of the coating stacks and further extensive testing.
Contrary to former RGB-designs, with the Baader RGBs the G- and R-filters form a very narrow gap but
do not overlap almost at all, in order to transmit the R-channel in sufficient width to work for Full-Frameand
Interline-Chips with equal effectivity, but to sharply exclude the spectral area around 580 nanometer
which carries the main light polluting emission lines of Mercury and Sodium street lamps. Baader RGBs
will produce a darker sky background.
Please order by December 18th at the latest for xmas - our offices close on Friday 20th December and we re-open on thursday January 2nd 2020. Our delivery charge for most of the UK is £2.95. All orders are shipped promptly, lower value items are sent Royal Mail 1st class and higher value or larger goods are shipped via reputable courier. All goods are shipped fully insured with FEDEX, UPS, DPD, DHL and Royal Mail, we do not use budget courier services, we can only ship to UK mainland addresses and are not able to ship to forwarding agents or PO boxes.
Our Order Lookup system (see very top of each page for the icon and link) updates the order status in real time for you - simply by entering your order number and postcode..
We ship each business day, orders received before lunch are normally shipped that business day. We also direct ship from our UK suppliers, this means we have access to thousands of products that can ship fast to our customers.
Deliveries to UK mainland addresses are all shipped with fully insured premium services for £2.95, *some exceptions apply including many AB, FK, HS, IV, KA, KW, PA, PH, ZE postcodes. We will quote delivery charges to these areas where applicable prior to shipping (this does not normally affect lower value items shipped by Royal Mail).
You must inform us within one working day if the goods are lost or damaged in transit so that we can make a prompt claim against the delivery company and correct the problem. Please ensure all address details are accurate, we cannot be responsible for failed deliveries or losses arising from incorrect delivery addresses.
You agree that proof of delivery supplied by our delivery company is sufficient evidence to establish that goods have been received.
If your product is sent by Courier they will attempt delivery twice and a signature will be required. If they are unable to deliver because you are not available and after 5 days you have not contacted them to re-arrange. the goods will be returned to us and the return delivery costs may be charged to you