Hi Renaat and Aileen,
First of all thank you for unselfishly producing your filters and sharing them with us.
My filters arrived the end of the week and as is every one else , I am impressed and wish to extend my gratitude.I can't wait to get these babies in the air.
I wasn't able to get in any flying but did spend some time tonight doing some tests that may not be terribly technical but I felt that it was a good starting point for a discussion on Color temperature and exposure compensation. Below are some results that I would like to share with our members.
First off I dusted off my old Color Temperature meter and in a darkened room as to not get any extraneous color pollution , I top lit the color meter with one of my shooting lights . I did however notice that the color temperature readings fluctuated ( only about 30 to 40 Kelvin but different) so that explains why I did a reading immediately before I added each Neutral Density.
You will see that prior to the ND 8 and ND 16 test the Meter was reading 5180K
Prior to the ND 32 the meter read 5170K
Prior to the ND 64 the meter read 5160K
Again not a big difference but a difference never the less.
However I think what is important is the shift is read as a difference from each individual reading immediately prior to covering the meter with each ND filter.
Next , I did a similar test with an exposure meter.
I set the meter to 640 ASA and 1/60th exposure time. For no reason , other than with the light I had above the meter , that would give me enough latitude to allow for more stops variation without having to make changes along the way, most likely making me more confused.
Prior to adding each Filter the Light reading was T16.
The only concern I had was that the ND 64 should be ( and correct me if I am wrong)a 6 stop filter.
I read it several times , at different settings with both my light and my meter and in each case my readings were 7 stops. Starting at T16. and ending in T1.4.
16 - 11- 8 - 5.6 - 4 - 2.8 - 2 - 1.4. ( 7 stops) All full stops so that was my only cause to gather opinions.
I don't profess to be any sort of expert and am in no way trying to demean this product.
I am, as it seems most members also are a huge fan of what you have done and been able to achieve in such a short period.
I would hope that this little test contributes in some way and is seen as nothing more than a starting point for further discussions.
Best regards
Tony
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