[coloseu]

1 -Relate AF to AE (AF/AE)

What is the advantage of having, in Matrix metering, the exposure related to the focus point?
Correct me if I’m wrong but it works as spot metering with the advantage of having eleven different spot metering points depending on what AF point you choose.
Also, the focus point are very small, does the meter operates only in that tiny focus point, or is it like the central spot metering when the area considered for exposure is a circle around the focus point?
I guess this is useful when you need to have a small subject well exposed and don’t want to focus and reframe (by using spot metering), correct?

2 – AE-L with AF locked

I don´t understand very well the purpose of this option. The exposure will be locked aslong as the AF will – when do you find this useful?

[Wheatfield]

1) It biases the exposure towards the meter segment encompassing the focus point. It does not work as spot metering.

2) I don't understand the usefulness of this either, perhaps others will.

[Canada_Rockies]

1) It biases the exposure towards the meter segment encompassing the focus point. It does not work as spot metering.

2) I don't understand the usefulness of this either, perhaps others will.

The function #2 does the equivalent of pressing the AE-L button at the same time as it locks focus. This could be useful under specific circumstances, where the subject is lit differently from the majority of the frame, but you want to have the subject elsewhere than the center of the frame.

[RiceHigh]

1 -Relate AF to AE (AF/AE)

When multi-point AF is activated, exposure at metering segment with AF point which achieved focus will have more weight in the evaluation of the metering.

However, since the (11) AF points distribution is not exactly aligned with the 16 segments of the light meter cells, I doubt the usefulness and practicality of this feature.

2 – AE-L with AF locked

This should be enabled for most of the time IMO. A quick check to the multi-segment metering of Pentax DSLRs by any user should reveal that the multi-pattern/segment logics tend to put *heavy* weight and emphasis on the centre segment.

It is therefore if the user uses only the central AF point only and then recompose more often, this features is a must for multi-segment metering or even centre-weighted average. Otherwise, metering will not be weighted on the subject where you focused. You have to push AE-L separately for precise metering anyway if this custom option is not enabled.

As for Spot metering, it is useful but for maximum flexibility and precise metering, I would still leave this option to "Off".

All other DSLRs of other brands actually lock AE with AF as default in green mode and in evaluative/multi-pattern/segment metering mode. In fact, only Pentax have to do it differently by default.