National Photocolor标准框架、NPC标准薄膜框架、National Photocolor薄膜分光镜、National Photocolor滤光片和窗口
National Photocolor标准框架
NPC标准薄膜框架备有1英寸、2英寸、3英寸、4英寸、5英寸和6英寸的圆形环,以及5英寸×7英寸的矩形框。顶面采用倒角处理。框架经黑色阳极氧化处理后,在内缘处进行研磨以形成平整面。然后将薄膜膜片张紧覆盖于平整面之上,并牢固粘合于倒角区域。机加工铝制框架背面设有两个带螺纹的安装孔。

| Size | ID | OD | Height | Mounting Holes |
|---|---|---|---|---|
| 1″ | 1″(25.4mm) | 1 3/8″(34.9mm) | 3/16″(4.8mm) | #2-56thd.x1/8″dp. |
| 2″ | 2″(50.8mm) | 2 3/8″(60.3mm) | 3/16″(4.8mm) | #2-56thd.x1/8″dp. |
| 3″ | 3″(76.2mm) | 3 1/2″(88.9mm) | 1/4″(6.4mm) | #6-32thd.x1/8″dp. |
| 4″ | 4″(101.6mm) | 4 1/2″(114.3mm) | 1/4″(6.4mm) | #6-32thd.x1/8″dp. |
| 5″ | 5″(127.0mm) | 5 1/2″(139.7mm) | 5/16″(7.9mm) | #6-32thd.x1/8″dp. |
| 6″ | 6″(152.4mm) | 6 1/2″(165.1mm) | 3/8″(9.5mm) | #6-32thd.x3/16″dp. |

| Nominal Dimensions | ||
|---|---|---|
| Inches | Millimeters | |
| A | 5 | 127.0 |
| B | 7 | 177.8 |
| C | 6 5/8 | 168.3 |
| D | 8 3/8 | 212.7 |
| E | 5/16 | 7.9 |
| F | 7/16 | 11.1 |

