C4 Blue Cooling

Balance Out Any Reddish Orange Hues
Available Sizes (mm)
49 52 55 58 62 67 72 77 82
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Description

TRANSMISSION CURVES

Our blue cooling filters are used to balance out any reddish orange hues. These filters raise the overall color temperature value and are generally used to adjust the white balance when shooting in tungsten or fluorescent lighting. The -120 mired value raises in color temperature is now referred to as the C12 filter.

There are 4 incremental variations in cooling filters offered: -20, -40, -80 and -120 mired values.

※Mired:
Contracted from the term micro reciprocal degree, the mired is a unit of measurement used to express color temperature. It is given by the formula: M (Mired) = 1000000/T (kelvin: Color Temperature) The increase and decrease by color temperature and the mired value become the opposite direction since the formula is a reciprocal.

Attention: Be aware of counterfeit filters

Attention: Be aware of counterfeit filters

In order to avoid purchasing one of those counterfeit filters we highly recommend to purchase only from official retailers that are recognized by HOYA's official global distributors. Prior the purchase kindly inquire and verify whether a retailer is authorized by HOYA global distributors. You may find the contact in the HOYA global distributors list.

Blue Cooling Filter

-20

82A (218)

C2

1.2

1/4

-30

82B (203)

1.4

1/2

-40

C4

1.4

1/2

-50

82C

1.5

3/5

-60

( C4 + C2 )

1.9

1

-80

(202)

C8

2.0

1

-90

80C

1.9

1

-100

( C8 + C2 )

2.4

1 1/4

-110

80B (281)

2.0

1

-120

C12

3.0

1 2/3

-130

80A

2.4

1 1/4

-140

(201)

( C12 + C2 )

3.6

1 4/5

-160

( C12 + C4 )

4.8

2 1/4

Hue

Mired Shift (ability for color conversion)

Filter Type

New Filter (combination)

Filter Factor

f-stops

Specifications
General Info
Model
HOYA C4 Blue Cooling
Type
COLORED
Available Sizes
49, 52, 55, 58, 62, 67, 72, 77, 82
Main Characteristics
ND Number (Filter Factor)
1.4
f-stops
0.5
Additional Info
Frame Material
Aluminum
Gallery
Associated
Ambassadors
Description
Specifications
Gallery
Associated
Ambassadors