How to test filters for a colour cast?

[ian-83]

Is there an easy way at home I can test a filter for a colour cast before using it when out? ND and grad filters.

Am I right in thinking filter on the camera then take a picture of some white paper?

 

[redsnappa]

Take a photo, if the picture it looks ok continue using the filter.

 

[chris malcolm]

Is there an easy way at home I can test a filter for a colour cast before using it when out? ND and grad filters.

Am I right in thinking filter on the camera then take a picture of some white paper?

Auto WB will take care of most colour casts, as will setting WB manually with a white or grey reference with the filter on. The only problem is that strong colour casts may seriously reduce the dynamic range of the filtered out colours, much as tungsten light seriously restricts blue dynamic range. To check for any colour cast, set WB manually without the filter, take a photograph, put filter on, take photograph. That will reveal the colour cast. Next you should test if auto WB or manual WB calibration will easily remove it.

 

[ian-83]

Auto WB will take care of most colour casts, as will setting WB manually with a white or grey reference with the filter on. The only problem is that strong colour casts may seriously reduce the dynamic range of the filtered out colours, much as tungsten light seriously restricts blue dynamic range. To check for any colour cast, set WB manually without the filter, take a photograph, put filter on, take photograph. That will reveal the colour cast. Next you should test if auto WB or manual WB calibration will easily remove it.

Can I do the testing against a white background to see if a colour cast is present?

Trying to think of a way to do it inside one evening as the only chance to get outside in daylight is at the weekend.

Is this the best way to deal with it out shooting

View: https://youtu.be/UfppLBzQuoc

 

[Jim_Tod]

Use a reference card and consistent lighting. See attached. If you do a shot with and without filter(s) then you can see difference in WB/ tint. Don;t know if you can simply transfer under other lighting conditions but it should give you a starter for 10 as to which way and by roughly how much to alter it if needed using filters. Link attached which hopefully helps.

http://lightroomkillertips.com/using-gray-card-setting-white-balance-lightroom/

 

[Nod]

Full NDs should be compensated for by the camera's WB - or should be consistent enough to be corrected in PP. Grads can be a bit trickier...

 

[ian-83]

Use a reference card and consistent lighting. See attached. If you do a shot with and without filter(s) then you can see difference in WB/ tint. Don;t know if you can simply transfer under other lighting conditions but it should give you a starter for 10 as to which way and by roughly how much to alter it if needed using filters. Link attached which hopefully helps.

http://lightroomkillertips.com/using-gray-card-setting-white-balance-lightroom/

Cheers seems fairly straightforward. seen grey cards on eBay for not much might pick one up, they seem to do a 3in1 kit with a grey, white and black cards which are credit card size

 

[Canon Bob]

Simply take a shot without the filter and then repeat with the filter (at the increased exposure time) and compare the two images....check the RGB histogram and they should be the same.

Bob