Optolong City Light Supression / Light Pollution Reduction CLS Filter - 2"

Description

Optolong City Light Supression / Light Pollution Reduction CLS Filter - 2"
Description
Ordering Info
USA Shipping
International Orders
Returns
Our eBay Store
1. PRODUCT DESCRIPTION
A. About Optolong's CLS FIlter
The Optolong CLS (City Light Suppression) filter is a broadband light pollution reduction filter that is designed to improve the visibility of various deep sky objects. It does this by:
Selectively reducing the transmission of wavelengths of light pollutants, specifically those produced by artificial lighting (including mercury vapor lamps, both high & low pressure sodium vapor lights, and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow)).
Being highly transparent to the main nebula emission lines at OIII (496nm and 500nm), H-beta (486nm), NII (654nm and 658nm), H-alpha(656nm) as well as SII (672nm).
B. Main Uses and Performance
Suitable for enhancing the contrast and details for both visual and photograghic purpose.
Suitable for color CCD cameras and unmodified DSLRs.
CLS has a wider passband than a UHC filter and is thus preferred when observing under mild to moderate light pollution from rural or suburban areas.
C. Spectral Curve Transmission Characteristics
95% transmission of main nebula emission lines:
H-beta 486.1nm, OIII 495.9nm and 500.7nm, H-alpha 656.3nm, and SII 672nm.
0.1% transmission of major transmission lines of artificial light pollution:
Hg (Mercury) at 435.8nm, 546.1nm, 577nm, and 578.1nm.
Na (Sodium) at 598nm, 589.6nm, 615.4nm, and 616.1nm.
D. Technical Specifications
Both surfaces are fine optically polished, accurate to 1/4 wavelength or better, and parallel to within 30 seconds or arc.
2mm thick Schott B270 optical glass substrate material.
Very high surface quality of 60/40 or better (US Military Spec MIL-O-13830).
E. Optical Coating Specifications
Multi layer anti-reflection coated.
Non-cementing optical substrate coating.
Electron-beam gun evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL (central wavelength) so that there is no deviation due to temperature changes during use.
Precise and homogeneous coatings ensure high values of desired passband and blocking of unwanted offband.
Every single filter is tested and passed by Optolong before shipping to dealers.
F. Other
2" astronomy filter with standard M48x0.75 male filter thread (no female thread, so it cannot be stacked with other filters).
Ultra-thin filter cell to minimize vignetting; clear optical aperture of 45mm.
Precision CNC-machined metal filter cell with sand blasted black anodized finish, anti-reflection treatment, and laser engraving.
High quality protective plastic storage case.
WARNING:
Optolong filters are not designed for direct solar observation. NEVER use these filters for observing the Sun, or permanent eye and equipment damage will result.
Note:
Occasionally, the product you receive might have a slightly different cosmetic appearance or labeling than what is shown. This can often change from batch to batch according to the whims of the manufacturer. However, you will always receive a brand new, original product as described above.
Description copyright: Agena AstroProducts - Reproduction without permission prohibited.
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2. ORDERING INFORMATION
Payment:
We only accept Paypal and major credit cards through Paypal.
Shipping Method:
United States Postal Service (USPS), unless otherwise specified.
Checkout:
Please pay for the item(s) within 3 days from your account on eBay or by using the link in the email you receive from eBay.
Shipping Discount:
We offer shipping discounts if you order multiple quantities/items. eBay will automatically show you the correct, discounted shipping costs when you check-out.
Combining Purchases:
You can combine shipping for items purchased from us on eBay within 3 days. Buy the items individually, and check out together for all items. eBay will combine the shipping weights and show you the discounted shipping cost. You must check out for all items together via eBay for this. We cannot combine shipping costs after you check out individually for your purchases.
Sales Tax:
8.5% sales tax added if your Ship-To address is in California.
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3. US SHIPPING
Delivery Time:
Most orders ship within 1 business day of receiving payment. First Class shipments will take 3-5 days to arrive after we ship it. Priority Mail shipments will take 2-3 days. However, these delivery times are NOT guaranteed by the USPS. Delays of up to 2 weeks can occur in about 5% of the shipments.
Tracking/Delivery Confirmation:
eBay will update you once your order ships. You can see the order status or tracking information from your eBay account at any time.
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4. INTERNATIONAL ORDERING / SHIPPING
Shipping Cost:
Click on the "Shipping and Payments" tab above and select your country to see your shipping choices and cost. If you need a shipping cost estimate for multiple items, please contact us.
Delivery Time:
1) USPS First Class International:
Delivery takes about 3-4 weeks after we ship your package.
This can frequently take 4-6 weeks or more for several countries (8 weeks for Italy, Argentina, and South Africa; 8-12 weeks for Brazil)
.
THERE IS NO TRACKING FOR FIRST CLASS SHIPMENTS. The information shown in your eBay account is just a customs form number - it is NOT a tracking number as incorrectly indicated by eBay.
Once your package ships, we can do nothing but wait until your package arrives. Please do not become impatient and contact us in 2-3 weeks if your package has not arrived. If you don't receive the package in 6 weeks, contact us and we will work with you to resolve the issue. If you don't want to take the risk of this delay, then DO NOT USE First Class mail - use Priority or Express shipping instead.
(2) USPS Priority Mail International:
Delivery takes 1 - 2 weeks after we ship your package. This can sometimes take 3-4 weeks to several countries. The USPS provides some basic tracking information for Priority shipping.
(3) USPS Express Mail International:
Delivery usually takes 5-10 business days after we ship your package. You will receive a tracking number with which you can track your shipment from USPS.com. Note: If you use this option, you must send us your phone number when you check-out or else your shipment will be delayed. This is required for international postal forms.
Again, these delivery times are NOT guaranteed by the US Postal Service. The most common reason for delays is slow customs inspection and clearance in your country, and can be very long, even for Express mail packages. Upon shipping your order, delivery delays are beyond our control, so do not leave us negative feedback or file a Paypal claim if your package is delayed. Delays are quite common but losses are very rare, so your patience/cooperation will be greatly appreciated.
Customs and Duties:
You are responsible for any duties and taxes that may be levied in your country. These are not included in the item price or shipping cost. We have no control over these charges and cannot predict what they may be or if they will be levied upon delivery. Customs policies vary widely from country to country (Some countries such as UK are strict about imposing hefty customs duties). It is your responsibility to check with your country's customs office to determine what these additional costs will be prior to bidding or buying. Customs fees are normally charged by the delivery company or your country's postal service, or collected when you pick the item up. These fees are NOT additional shipping charges.
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5. RETURN/EXCHANGE POLICY
US Orders:
Returns must be shipped back
within 30 days
. All returned items must be in brand new, resalable condition with original manufacturer’s packaging. A minimum restocking fee of 10% will be deducted if there is any evidence of use or wear, dirt, scratches, missing packaging/parts, etc. We may levy a larger restocking fee if the condition warrants it, or even refuse returns entirely if returned in heavily used/abused condition. Shipping fees are non-refundable (for items with free or discounted fixed shipping, the actual outbound S&H cost we incurred will be deducted) and you are responsible for all return shipping costs. Please contact us first before returning an item.
International Orders:
No returns/exchanges accepted unless the item we shipped is defective. Please research the product and ask us any questions BEFORE you purchase to make sure you are buying the correct item for your needs.
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