Canon EOS 400d

tThanks for the links to the sites selling the ac adapter. I've now ordered one from Adorama. No more charging batteries etc. One permanent solution for the observatory as far as I'm concerned.

Cheers,

Hi Anthony,
8-9 hours,!?!?, this is very interesting, is this 8-9 hours of long exposures, how on average is that 9 hours spent?

Hi Dave,

I am waiting for an opportunity to do some illegal work at one of the archaeological grounds about 2.5 hrs west of Athens. My objective is a 9-10 hr star trail photo involving the grounds at Ancient Delphi and the primary reason I picked up these batteries is because of this project.

I have experimented with them and I can easily pursue a nine-hr star trail photo (10-min subs) using these two batteries in my power pack. I purposely have reset the LCD to never display when a photo is taken so as to minimize power consumption as much as possible (this is the greatest source of power consumption since each and every photo we take normally displays for two seconds). Another reason for having the display off is not to alert anyone that I am on the grounds illegally after hours.

Your secret is safe with us Anthony, or atleast it will be until the pic shows up on the cover of sky&telescope. :lol:

Looks like you've got a good set of batteries, it will be interesting to see how they age.

It is claimed that the AC adapter redices noise :shock:

From the digitalastro forum:
AC adapter reduces noise
Posted by: "bradgregley10" bradgregley10@yahoo.com bradgregley10
Thu Nov 30, 2006 12:04 am (PST)
I have taken a 10 minute dark using the regular battery and using the
ac adapter in place of the battery.

I am surprised at how much lower the noise is. It is almost the same
reduction as cooling the chip for a 20D.

tinyurl.com/y78xyn

Presumably this gain is available to all the EOS Canon cameras.

The battery must really heat up when used for long exposure imaging
and the ac adpater does not.

Keith..

Keith,
I have a theory touching on this subject and is part of the reason I went with an adapter in the first place, its not exactly what you posted about.

The longer the camera is on, the warmer it gets, as heat affects the image noise, then if you image during the night the camera heat goes up as you go on so dark frames from earlier on are not true dark frames for later on, BUT, if you have an AC adapter and turn the camera on a number hours before you use it, it gets time to warm up so by the time you use it it has reached some sort of thermal plateau, so dark frames will be more accurate. it only an idea.

If someone with a crap batter like mine is comparing their images against a time when they're using an AC adapter, this might account for the behaviour, simply because the camera is able to stay on longer and get time to become thermally stable when using an adapter.

I have never noticed the battery even been warm, nevermind hot.