Battery life on auto scopes

[solarwallace]

Hi all

Apologies if this has been asked before but I'm basically in the midst of replacing my existing scopes and thinking about which new scope to got for.

Possibilities are the usual ones really:

SW 200P EQ5 or the SW 200 Flex Auto (usual suspects)

I've ruled out the 200 Skyliner Dob (maybe wrongly) because I want to use a webcam with which ever scope I buy for a bit of planetary imaging as well as mainly visual stuff. However, my actual question is (at last)

How do you find battery life when using a tracking scope?

I know this will largely depend on which scope and which power source but some generalities would be great

I know the 200P EQ5 doesn't come with tracking but it could be upgraded with motors later on. I had an EQ3-2 mount and once I got to grips with it (first scope), I really liked it. However, you do pay more for the mount and maybe an auto dob would be the way to go.

Of course I'm still tempted by the plain old dobs. I didn't understand aperture fever until I started thinking seriously about a new scope But then there's the size of the thing to consider as well.

It's mainly the battery life I'm curious about. I don't like the idea of being stuck because my batteries have gone flat:(

Thanks

Steve

[reddoss]

The cheapest option is get a car jump starter battery from somewhere like Maplin.

They range in price from £40 - 25 and are 17 Amp hour batteries. When fully charged they will last for many hours powering a mount. They only run out of power if people use them for several observing sessions and forget to charge them in between times.

[WayBig]

I use the smaller 7ah powertank with a 250 auto dob, It lasts fine for me. I normally recharge it avery 3 or 4 sessions (each session being 2-3 hours) just to make sure, but I think there's still plenty of juice in it when I plug it in to charge it as the recharge needed light rarely comes on.

I dont have anything but the dob plugged into it and do most of my long range slewing by pushing it as it's quicker and quieter.

[West End Wendy]

I also have the 7ah power tank. I use it for tracking on my equatorial mount. I think the RA drive draws about 250mA, so in theory a 7ah battery will last 28 hours!

In practice though, those lead acid batteries don't like being run down too much which is why people tend to buy larger batteries than they should need.

Tim.

[solarwallace]

Thanks for your replies it's put my mind at rest. Just gotta pick a scope now