How Much Light?
I wondered how much light we actually need or want for camera scanning. The more the merrier - but let’s give it a few thoughts and measurements before getting out the big guns.
As I wrote a few posts up, I use a Kaiser slimlite plano 2454, which, according to its operating instructions, has a light density of 600 cd/m2. I ran all my tests using it as backlight but I’d like to use it as a light table to check the film strips rather than using it as an oversized backlight. Which brought up the question of how much light I actually needed. I’m not overly fond of flashes, so I had a look at a few LED panels that promised good light quality as well as a reasonable price.
According to what I see on this page, and based on what I can easily get where I live, I had a look at the specs of the Aputure AL-M9 and -MX panels. They looked good and the prices are okay. Both panels promise a CRI of > 95. Now, the question arose if the M9 had enough power or if I needed the MX.
Here is what I found
- Aputure AL-M9, 5x8 cm, LUX at 0,3m: ≥ 900
- Aputure AL-MX, 6x9 cm, LUX at 0.3m: ≥ 2400
- Kaiser slimlite, 22x32cm. LUX at 0,3m: ca. 350 (measured, Lux in usual use at 2 cm: 1400)
If I’m not mistaken, this would mean that the M9 has plenty of light if I put it 0.1-0.2 m away from the negative. Other than having more power, the MX can vary colour temperature and looks more robust.
I’d appreciate comments or corrections if my calculations are wrong or if anyone uses one of the mentioned AL-Ms. Thanks in advance.