I have been comparing my Pentax Takumar 28mm f3.5 lens (via an adapter) to my Canon 18-55mm 3.5-5.6 IS lens.
When I have them both set to the exact same f-stop, the exposure meter of the camera is a few ticks lower when the Takumar lens is being used than it is when the Canon lens is being used.
What could be contributing factors to this? Is it the lens coating? I have read that t-stop takes into account the actual transmitted light, as opposed to the theoretical based f-stop. So my question still sort of remains that same. Why does my one lens have a different t-stop to my other lens, when both are at the same f-stop?
What are the contributing factors to t-stop?
No comments:
Post a Comment