Power use of the E-510

While perhaps a bit esoteric for some, knowing how much power your camera actually uses in different configurations can be essential in stuations where you need to get the most out of your battery. Minimizing power usage can also speed up focussing with some lenses.

While this article is about the E-510, many of the observations can be carried over to other Olympus cameras.

Setting up a baseline

The baseline is the starting point used in comparisons. It is a configuration with most options turned off. During this article if I say that a certain power usage is +20% of base it means that the camera is using 20% more power in that configuration than it did in the baseline configuration.

The baseline configuration is as follows:

• Shooting mode: P(rogram)
• LCD info: off
• Live view: off
• AF mode: S-AF
• Lens: ZD14-54mm II at 14mm

Note that these settings result in about the lowest power usage available. If you really need to save batteries, this is the configuration for you.

Conclusions

These are the detailed conclusions that I have reached based on this testing. If you just want teh spicy bits there's a summary below. For the data these conclusions are derived from, look even further down.

Influence of autofocus mode

Focus mode matters considerably for power drain. The MF modes (AF-S+MF, AF-C+MF and MF) use from 20 to 25% more power than the baseline. This means that if battery life is an issue you should not leave the camera on these modes unless you have a good reason.

This MF difference did NOT apply to my Sigma 135-400mm. Presumably this is due to the mechanical coupling of the AF ring. This makes me believe the same will be true for ZD lenses with direct coupling.It is theorized that this may be due to the body having to continually poll the lens's focus-by-wire mechanism.

In ready state after a restart, S-AF and C-AF use the same power. However during a half-press S-AF will go to 25% over baseline (208 mA) and C-AF will go to 50% over baseline (248 mA). After the half-press, S-AF will return to the baseline but C-AF will go to a state that's still 19% over baseline! It will stay there until you restart the camera or switch to S-AF and back.

Interestingly there is no difference between S-AF+M and C-AF+M during a half-press

Influence of IS mode

Having IS on in ready state uses an extra 3-7% of power, depending on the lens. However taking an actual picture with IS on makes this difference a lot bigger, see the live view section for some examples.

Noteworthy is that turning IS on and then off again sometimes leaves the current drain slightly higher than before until you restart.
Both IS modes use the same amount of current in ready state.

Live view

Live view yielded some interesting results.

For Most lenses, live view uses about 190% more power than the baseline (484 mA, that's about 3 times as much power).

This was true for my 14-42mm, my 135-400mm and my 9-18mm. It was not, however, true for my ZD 14-54mm II, which used the regular 484 mA at 54mm but used a whopping 590 mA at 14mm. This focal length dependant effect could not be replicated with any of the other lenses I listed, including the 14-42mm which has an otherwise similar view.

Using the x7 blowup in live view increases current drain to 213% over baseline (520 mA). This was true on both ends of the 14-54mm II, meaning that at 54mm (and for most lenses over their entire range) using this function increases power requirements, but at 14mm for this lens it decreases them. Yeah I don't get that either 

Live view power drain is independent of the amount of light in the scene. Bright lights and a closed lens-cap produced the same results.

Live view + IS

Just turning IS on during live view does not significantly increase power drain (just a few mA difference). However using the IS preview function (keeping the IS button pressed) gives us some interesting data on the IS usage.

Here it becomes clear that IS1 uses a LOT more power than IS2. There was a consistant difference of 80-90 mA between the two modes. For most lenses this meant a current drain of about 690-720 mA total for LV+IS1 and 600-620 mA for LV+IS2.

The outlier was again the 14-54mm at 14mm, which required a respective 792 and 711mA for the two modes. In one test it even reached 815mA, the highest value by far that I recorded.

Other findings

• Changing settings can make the baseline current drain go up. Turning the camera off and on again resets this.
• P/A/S/M has no effect on baseline
• Different Metering patterns (spot, highlight, ...) have no effect on baseline
• Baseline mostly independent of lens (difference of +-5%)
• Sleep mode (the one that triggers after about five minutes) lowers power drain to less than 10 mA, which is off for most practical purposes.
• Picture review in S-AF+M mode used no more power than just having the camera in ready state. I forgot to test this in the other focus modes.

Summary of findings

For those who don't want to read through all the text before, here's a  summary of the more interesting findings.

• AF-S+MF, AF-C+MF, MF modes use 20-25% more power than the baseline (ca 50mA)
• The above was not true for my Sigma lens, possibly cause it has mechanical coupling
• Half-press uses about 25% more power than baseline for AF-S, 50% more than baseline for all others.
• After Half-press on AF-C power useage remains higher than before
• IS modes use about 3-7% more power in ready state (not taking a picture) than the baseline. This was the same for both modes
• Power usage remains higher even after turning IS off, until restart.
• Live view uses about 3 times as much power as the baseline for most lenses and most focal lengths
• The 14-54mm II uses a lot more power in live view at 14mm than any of my other lenses. At 54mm it uses the same as the others. Difference between 14mm and 54mm: 20% power.
• All other lenses use more or less the same independent of focal range
• Live view power usage is independent of the amount of light in the scene: Brightly lit or lenscapped made no difference.
• using the 7x blowup in live view increases the power drain by about 8% for most lenses.
• For the 14-54 II at 14mm the above actually decreases power drain, to the same value (520mA)
• IS1 uses a lot more power when active than IS2 (about 90mA more)
• Highest power drain measured was 815 mA, this was using IS1 preview in live view on the 14-54mm at 14mm. Same operation on other lenses (or at 54mm) used about 710mA
• Changing settings can make the baseline current drain go up. Turning the camera off and on again resets this.
• Even with that, power drain creeps up over time, presumably as things heat up

Measured Data

This is (a subset of) the data as measured. Generally every line is the average of 5 or more measurements. If you want you can skip to the conclusions below.

 Columns

• #: Line number
• IS: Image Stabilizer setting used. Can be Off, IS1, IS2 or IS1/2 (meaning same resulst for both modes)
• LV: Live View: can be on or off
• Display: What was being displayed on the back LCD. Can be Off, Info bright, Info dim (when the LCD is in lowpower mode) or LV (live view)
• FL: Focal Length
• Current is the power drain in milli ampères( mA)
• delta is the difference with the baseline. Note: +100% means power use was twice that of baseline.
• Half-press: current whiel the shutter is half-pressed, in mA