While reading the latest reviews, there have been reports of the new Live Photo feature having a negative effect on the image quality in low light conditions.
The explanation for this: For the video recording (with about 15 fps) to capture the live effect, images must be taken very quickly, hence the exposure time must be kept short (max. 1/15”). To achieve this, the ISO is increased, resulting in more noise and thus lower image quality. Sounds obvious.
However, we could not imagine that Apple would accept such compromises in the photo quality. This would mean that the maximum exposure time would be around 1/15”. If this was the case, there would be no advantage in using the iPhone 6s Plus optical image stabilizer (longer exposure time instead of using a higher ISO value).
After reviewing some of our in-house test pictures, we can reassure you: The new Live feature has no negative impact on the image quality! Images are still captured with a maximum shutter speed of 1/4” for the 6s Plus. (i.e. 1/17” for the 6s) The difference in maximum exposure times is due to the presence of the optical image stabilizer in the 6s Plus.
So rest assured, there is no impact to the image quality while using the new Live feature!