View Full Version : HLD-4 and focus speed with the E-5

4th March 2011, 10:53 AM
Has anyone noticed any benefit in having two batteries in the grip rather than one concerning focus speed.

I was asked this by a hire customer this morning and I couldn't really answer the question, but promised to experiment.

I tried the E-5 with a Mark 1 50-200 and couldn't notice any difference in AF speed between on or two batteries fitted. In fact when I did the single battery test that battery started to warn it was about to expire.

My suspicion is that the HLD-4 uses each battery individually and switches to the second if the first is low.


Ross the fiddler
4th March 2011, 11:25 AM
Maybe a confirming clarification of the HLD-4 battery function (parallel or controlled sequence) might help with this perception. I know I enjoy long usage from the batteries, even the generic ones & maybe there is less slowing of the motor on 70-300 lens, but then again, it might be just because it has been hinted, that we want to believe it makes a difference. If the batteries are directly in parallel, it has to minimise voltage drop & maintain voltage to the motor circuit & that would be noticable in the heavier lenses perhaps where there is a greater chance of a laboured motor drive.

A lab styled test would be useful if someone had the patience & time to conduct it well & scientifically (that thinking comes from being married to a science teacher). I'm interested to see what other responses will be.

David Morison
4th March 2011, 11:34 AM
I would certainly be interested in the results of such a study as I am considering buying an HLD-4. Normally I am happy without a battery grip and a couple of spares in my pocket but with the ZD 300mm f2.8 a lot of metal and glass is moved around during AF and it does tend to use batteries faster than normal so an HLD-4 could be useful.


4th March 2011, 01:11 PM
When the E-1 was launched (all those years ago) Olympus stated that continous focus was improved when the grip was attached, I assumed that was because of the bigger battery used.

I remember a discussion a year or two ago (maybe on another site) discussiong focus speed and battery power with the E-3, I believe that concluded that the standard single battery was on the low side for lenses like the 14-35 (Alright to start with but soon fell off). Some improvement was seen with the grip although some thought it was because your power didn't fall off as fast so it was in an acceptable range for longer.


5th March 2011, 07:09 AM
My suspicion is that the HLD-4 uses each battery individually and switches to the second if the first is low.


Ian, the translation is a little odd in places, but this site (http://translate.google.co.uk/translate?u=http%3A%2F%2Fwww.four-thirds.cn%2Fforum%2Fthread-76109-1-1.html&sl=zh-CN&tl=en&hl=en&ie=UTF-8) is pretty informative.

Essentially, it seems that the two batteries run in parallel with decoupling diodes.
Also changing these diodes to ones with a higher spec can help alleviate the premature low battery warning that has been reported by some users.

5th March 2011, 08:09 AM
Ian, the translation is a little odd in places, but this site (http://translate.google.co.uk/translate?u=http%3A%2F%2Fwww.four-thirds.cn%2Fforum%2Fthread-76109-1-1.html&sl=zh-CN&tl=en&hl=en&ie=UTF-8) is pretty informative.

I don't think I really understand it but I'm intrigued to know how the tiger skin gets in there. :confused:

Ross the fiddler
5th March 2011, 12:20 PM
Thanks peak4 for the link.

Well, now I've got my answer. The batteries are in parrallel operation but with the protection of double Schottky Diodes (doubling the current capacity of each diode) from each battery (& they are not zener diodes). Diodes have a forward voltage drop across them, but the Schottky diodes have a very small voltage drop compared to other diodes plus they are known for their very fast switching capability (used in switch mode power supplies).

Out of this information, I would suggest that unless each battery is exactly at the same charge, then there is a chance the batteries could switch from one to both etc. to share a light load, but under a heavy load, it would be more likely that both (pairs) are conducting. Well that's my theory anyhow. :D Fully charged batteries will maintain optimum drive for the lens motors for (in theory) double the length of time that a single battery would.

5th March 2011, 04:51 PM
Ross, I suspect it may not just be about doubling the current capacity of each diode, but more about minimising the forward voltage drop. If they share the load then the voltage drop will be lower. I wonder if this is why some users report misleading battery warnings. Either some of the diodes aren't the best spec, or one has gone open circuit; the current through the remaining diode increases, but so does the forward voltage drop,thus misleading the voltage sensor in the camera.

3rd February 2013, 09:08 PM
Hello Everybody!

I’ve the same problem with E3+HLD4.
1) I’ve put new battery ENERGIZER HIGTECH in the loader AAH1 : Voltage is about 9.68V. I’ve displayed about 50 pictures et the battery logo appears in read. I’ve check then the voltage 9.53V
2) I’ve put 6 batteries (NiMh) full loaded in the loader AAH1. Voltage is 8.23V, I’ve displayed 10 pictures and I’ve got the « Battery Empty »Message. [8.23/6 =1.35V per battery …). So I’ve check the voltage of the battery: 8.1 which is higher than the specification….
3) I’ve loaded my HLD4 with 2 compatible BLM5 for 8.3V each. I’ve displayed 20/30 and the battery logo went to read (in the left up corner).
4) Remove HLD4 and took 60/70 photos with flash with 100 displayed pictures, everything is fine.
5) Check with voltmeter and ampmeter , the drop at the Schottky diode is about 0.32V with 177mA getting out the 6 pack battery holder. [Just remember that with the AAH1 , « + » if from the « right battery position » and the « -« from the left battery position. I don’t know the standard current for the E3 ? With 96mA the 6 pack Battery drops 0.28V in the Schottky diode.
6) We went in Cambodia in August, the HLD4 was not so frustrating but with Two compatible BLM5 the max shoot was about 150 pictures. Now it is just 10 pictures and the voltage of the battery is always high.