ND Foil for Aurora Flat Field Panels

To obtain the correct brightness level from the Aurora flat field with certain telescopes it may be necessary to add a neutral density foil. This will reduce the light level from the panel to a point where the correct flat field can be obtained. Foils of different values can be combined.

Our recommendation is that telescopes with a focal ratio of approx F6 will require an ND1.2 foil. For telescopes with a focal ratio of F4 then we suggest adding an ND0.9 to the ND1.2.

If foils are ordered with an Aurora Flat Field, then we will fit the foil to the filter before delivery. If this is not required, please notify us.

ND Foil for Aurora Flat Field Panels

To obtain the correct brightness level from the Aurora flat field with certain telescopes it may be necessary to add a neutral density foil. This will reduce the light level from the panel to a point where the correct flat field can be obtained. Foils of different values can be combined.

Our recommendation is that telescopes with a focal ratio of approx F6 will require an ND1.2 foil. For telescopes with a focal ratio of F4 then we suggest adding an ND0.9 to the ND1.2.

If foils are ordered with an Aurora Flat Field, then we will fit the foil to the filter before delivery. If this is not required, please notify us.

ND Foil for Aurora Flat Field Panels

To obtain the correct brightness level from the Aurora flat field with certain telescopes it may be necessary to add a neutral density foil. This will reduce the light level from the panel to a point where the correct flat field can be obtained. Foils of different values can be combined.

Our recommendation is that telescopes with a focal ratio of approx F6 will require an ND1.2 foil. For telescopes with a focal ratio of F4 then we suggest adding an ND0.9 to the ND1.2.

If foils are ordered with an Aurora Flat Field, then we will fit the foil to the filter before delivery. If this is not required, please notify us.

ND Foil for Aurora Flat Field Panels

To obtain the correct brightness level from the Aurora flat field with certain telescopes it may be necessary to add a neutral density foil. This will reduce the light level from the panel to a point where the correct flat field can be obtained. Foils of different values can be combined.

Our recommendation is that telescopes with a focal ratio of approx F6 will require an ND1.2 foil. For telescopes with a focal ratio of F4 then we suggest adding an ND0.9 to the ND1.2.

If foils are ordered with an Aurora Flat Field, then we will fit the foil to the filter before delivery. If this is not required, please notify us.

ND Foil for Aurora Flat Field Panels

To obtain the correct brightness level from the Aurora flat field with certain telescopes it may be necessary to add a neutral density foil. This will reduce the light level from the panel to a point where the correct flat field can be obtained. Foils of different values can be combined.

Our recommendation is that telescopes with a focal ratio of approx F6 will require an ND1.2 foil. For telescopes with a focal ratio of F4 then we suggest adding an ND0.9 to the ND1.2.

If foils are ordered with an Aurora Flat Field, then we will fit the foil to the filter before delivery. If this is not required, please notify us.

A Bahtinov Mask is a focusing aid. When fitted over a lens, it creates a 6 pronged diffraction pattern. As you adjust the focus, the middle spikes will move. When exactly in the middle, perfect focus has been achieved.

This small 49mm Mask is designed for use with camera lenses. It is mounted to a filter holder with an M49 thread allowing it to be screwed directly into a camera lens.

A Bahtinov Mask is a focusing aid. When fitted over a lens, it creates a 6 pronged diffraction pattern. As you adjust the focus, the middle spikes will move. When exactly in the middle, perfect focus has been achieved.

This small 52mm Mask is designed for use with camera lenses. It is mounted to a filter holder with an M52 thread allowing it to be screwed directly into a camera lens.

A Bahtinov Mask is a focusing aid. When fitted over a lens, it creates a 6 pronged diffraction pattern. As you adjust the focus, the middle spikes will move. When exactly in the middle, perfect focus has been achieved.

This small 55mm Mask is designed for use with camera lenses. It is mounted to a filter holder with an M55 thread allowing it to be screwed directly into a camera lens.

A Bahtinov Mask is a focusing aid. When fitted over a lens, it creates a 6 pronged diffraction pattern. As you adjust the focus, the middle spikes will move. When exactly in the middle, perfect focus has been achieved.

This small 67mm Mask is designed for use with camera lenses. It is mounted to a filter holder with a M67 thread allowing it to be screwed directly into a camera lens.

A Bahtinov Mask is a focusing aid. When fitted over a lens, it creates a 6 pronged diffraction pattern. As you adjust the focus, the middle spikes will move. When exactly in the middle, perfect focus has been achieved.

This Mask is made to fit the 83mm x 83mm format used by the popular Cokin P filter system (and its clones) for camera lenses. Rather than having a specific screw in mask for each lens, you can use the Cokin system with adapters to fit a variety of lens filter threads. The Mask is laser cut with a fine mask and so will work well with lenses of short focal length and above.