Can someone tell me the difference between the Compact Battery Pack E and Transistor Pack E. If it helps, I use a Canon Elan 7E and a 550EX flash.

-- Michael Ray (jmray@vallnet.com), May 29, 2001

Answers

According to Canon's advertising literature, the Compact Battery Pack CP-E2 is a "modified version of the original Compact Battery Pack E". The new version accepts AA-size lithium batteries. Weight: 5.5 oz (doesn't say if this is with batteries or not, I assume without)

The Transistor Pack E can be used with a choice of power supplies including Battery Magazine TP (sold separately - holds 6 C-size alkaline manganese batteries and NiCd pack TP, rechargeable sealed battery pack). Includes Battery Magazine TP and Connecting Cord ET according to their literature.

Both will work with 550EX flash according to Canon literature.

I hope this helps.

Sue

-- Susan Butler (sbutler2@ameritech.net), May 29, 2001.

I have the transistor pack, which I use with 6 C size alkalines (I don't have the charger for the NiCd). Used last with an EOS3 + 540EZ.

Flash recharge is nearly instant with fill-flash. A full flash requires a little longer, but nothing like the time required without the pack. It will also retain this fast recharge for many rolls of film. The 4 batteries in the flash DO run down though, so have some spares handy for a long day.

I use it very often, as the fast recharge is worth the extra bulk.

However, I notice from my 540 manual and my new 550 manual that the compact battery pack gives nearly the same statistics of recharge and number of flashes. The compact pack is much smaller, so if you have the choice between the two then the compact pack seems like the logical choice - unless you need to use the rechargeable battery in the transistor pack.

-- Paul McSweeney (paulmcs@clear.net.nz), May 31, 2001.

Besides using C cell, instead of AA batteries, I believe the transistor pack is a high voltage pack. This enables faster recharge times than just batteries alone. Even though the voltage of the batteries is the same, it is stepped up by the transistor pack. Sort of like Canon's version of a Quantum Turbo, Jackrabbit, etc.

-- Brad Hutcheson (bhutcheson@iname.com), May 31, 2001.

I would have expected statistics like Brad has indicated. Oddly enough, the recharge time in the Canon literature indicates that the compact pack is as fast as the Transistor pack.

-- Paul McSweeney (paulmcs@clear.net.nz), May 31, 2001.

I find the statistics to be a bit strange too. The 550EX manual does confirm (in a round about way) that the transistor pack is high voltage, but the chart claims it doesn't recycle faster. What is even stranger is that the C batteries don't last any longer than the AA batteries, at least not when alkalines are compared. NiCd AA vs. NiCd pack TP is a different story though. By the way, the 550EX manual refers to the high voltage pack E315, which can only be the Transistor Pack E, since the manual says only two external power sources are available. My guess would be that the pack puts out 315 volts, but it is just a guess.

-- Brad Hutcheson (bhutcheson@iname.com), June 01, 2001.

From my own testing - 550EX recycle times in seconds for a full power manual flash: Alkaline NiCd Transistor Pack-E 4 <2 Compact Battery Pack-E 6 2 550EX 4xAA 20 5

BTW, both the Transistor Pack-E and the Compact Battery Pack-E are high-voltage power packs. I've measured the Compact Battery Pack-E output at 270 VDC.

Dave Herzstein dherzstein@juno.com http://www.kjsl.com/~dave

-- Dave Herzstein (dherzstein@juno.com), June 01, 2001.

Dave, could you clarify your stats a bit? Maybe it is lack of sleep on my part, but they seem to be running together. I knew 270 volts had stuck in my head from somewhere, but I thought that it was for a Quantum Turbo. Is the Transistor Pack E the same voltage as the Compact Battery Pack E?

-- Brad Hutcheson (bhutcheson@iname.com), June 02, 2001.

Sorry, my table got mangled...

I didn't measure the voltage from the Transistor Pack E, but I'd assume its the same.

	Alkaline	NiCd
Transistor Pack-E	4	<2
Compact Battery Pack-E	6	2
550EX 4xAA	20	5

-- Dave Herzstein (dherzstein@juno.com), June 02, 2001.