|
I have been using a Hoya R72 (89b) for shooting infrared photographs for both with film and now, with digital. I recently discovered the new Cokin 0007 (89b) filter. After purchasing one of these new Cokin filters, I was excited to try it. I discovered that the raw image from each was different. It appeared to me that the Cokin allowed more visible light through than the Hoya. This was even though both filters are rated as having 50% transmission at 720nm. Below are comparisons of these two filters that were only resized, along with a black and white version that was resized, desaturated, and auto-leveled. This was done with Photoshop 7. |
 |
 |
| Hoya 89b straight from the camera |
After adjustments in Photoshop |
 |
 |
| Cokin 89b straight from the camera |
After adjustments in Photoshop |
|
| |
| Notice the difference between the raw images. The Cokin obviously has more visible light passing to the sensor. I don't know what the actual transmission curve looks like. While the transmission curve for the Hoya filter is readily available, according to Cokin, the transmission curve for their filter is not. |
| Back |