Daystar Filters Flat Cap Imaging Diffuser - Available in 12 Sizes
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Warning: The Daystar Flat Cap is NOT a solar filter. Not for use in a concentrated beam. Eye or equipment damage will result unless used in combination with a safe solar filter or solar telescope. FlatCap must be the first component to encounter light.
The DayStar FlatCap is a Gaussian diffuser that is temporarily installed over the front of your telescope when taking flat field reference images. By strongly blurring the Sun, the only details you will see in the reference image are from defects in your imaging train that can be removed in software.
FlatCap is sold by inside diameter of the mounting cap. Measure the outside diameter (OD) of the frontmost component of your telescope or ERF, and then round up to the next larger size. For example, a telescope with a 160mm front should use model FC170, and then optionally install the included felt pads for a secure fit. Do not buy based on the aperture of your telescope. Measure the front of the tube/dewshield/ERF very carefully before purchase to select the correct size.
Specifications:
- Construction: Spun Aluminum mounting ring with polymer diffuser
- Intensity distribution: Gaussian
- Divergence angle: 4 degrees FWHM
- Exposure time adjustment factor: 100x longer
- Maximum field of view: 1 degree with Sun backlight
- Wavelength transmission range: 350-800nm
- Operating temperature: -10 to 100°C (14-212°F)
Size Table:
- FC90 FlatCap: fits 80-89mm tube/dewshield OD or 63mm ERF
- FC100 FlatCap: fits 90-99mm tube/dewshield OD
- FC110 FlatCap: fits 100-109mm tube/dewshield OD or 80mm ERF
- FC120 FlatCap: fits 110-119mm tube/dewshield OD or 90mm ERF
- FC130 FlatCap: fits 120-129mm tube/dewshield OD or 100mm ERF
- FC140 FlatCap: fits 130-139mm tube/dewshield OD
- FC150 FlatCap: fits 140-149mm tube/dewshield OD
- FC160 FlatCap: fits 150-159mm tube/dewshield OD or 130mm ERF
- FC170 FlatCap: fits 160-169mm tube/dewshield OD
- FC180 FlatCap: fits 170-179mm tube/dewshield OD or 150mm ERF
- FC190 FlatCap: fits 180-189mm tube/dewshield OD
- FC210 FlatCap: fits 190-209mm tube/dewshield OD
Note: Newton’s Rings or intereference fringes will not be corrected by flat fields; use Daystar's Interference Eliminator adapter to remove these before performing flat field correction.
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| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
Warning: The Daystar Flat Cap is NOT a solar filter. Not for use in a concentrated beam. Eye or equipment damage will result unless used in combination with a safe solar filter or solar telescope. FlatCap must be the first component to encounter light.
The DayStar FlatCap is a Gaussian diffuser that is temporarily installed over the front of your telescope when taking flat field reference images. By strongly blurring the Sun, the only details you will see in the reference image are from defects in your imaging train that can be removed in software.
FlatCap is sold by inside diameter of the mounting cap. Measure the outside diameter (OD) of the frontmost component of your telescope or ERF, and then round up to the next larger size. For example, a telescope with a 160mm front should use model FC170, and then optionally install the included felt pads for a secure fit. Do not buy based on the aperture of your telescope. Measure the front of the tube/dewshield/ERF very carefully before purchase to select the correct size.
Specifications:
- Construction: Spun Aluminum mounting ring with polymer diffuser
- Intensity distribution: Gaussian
- Divergence angle: 4 degrees FWHM
- Exposure time adjustment factor: 100x longer
- Maximum field of view: 1 degree with Sun backlight
- Wavelength transmission range: 350-800nm
- Operating temperature: -10 to 100°C (14-212°F)
Size Table:
- FC90 FlatCap: fits 80-89mm tube/dewshield OD or 63mm ERF
- FC100 FlatCap: fits 90-99mm tube/dewshield OD
- FC110 FlatCap: fits 100-109mm tube/dewshield OD or 80mm ERF
- FC120 FlatCap: fits 110-119mm tube/dewshield OD or 90mm ERF
- FC130 FlatCap: fits 120-129mm tube/dewshield OD or 100mm ERF
- FC140 FlatCap: fits 130-139mm tube/dewshield OD
- FC150 FlatCap: fits 140-149mm tube/dewshield OD
- FC160 FlatCap: fits 150-159mm tube/dewshield OD or 130mm ERF
- FC170 FlatCap: fits 160-169mm tube/dewshield OD
- FC180 FlatCap: fits 170-179mm tube/dewshield OD or 150mm ERF
- FC190 FlatCap: fits 180-189mm tube/dewshield OD
- FC210 FlatCap: fits 190-209mm tube/dewshield OD
Note: Newton’s Rings or intereference fringes will not be corrected by flat fields; use Daystar's Interference Eliminator adapter to remove these before performing flat field correction.
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
Daystar Filters Flat Cap Imaging Diffuser - Available in 12 Sizes