D. GPS unit. Dawn Technologies, di-GPS

[Carrie]

With news of a new GPS unit available ( here ) I thought it might be timely to post a review of a (different) GPS unit that I've had for around 6 months now.

Summary.
Good - ease of use; accuracy; signal pick up (other than from cold)
Not so good - signal lock on time from cold; battery life; cost.
Am I glad it was bought for me? YES

Ease of Use
The di-GPS adds the GPS data to the camera EXIF files in the camera (a lot of GPS units need to be downloaded to the computer and software then links the GPS time and the photo time to attach the right GPS data to the right photo).

Accuracy
I use adobe lightroom, which automatically picks this EXIF information up, and with one click takes me through to google maps. I've done a test walking along the local prom, and the positioning is pretty much spot on. One reading had me on the wrong side of a breakwater, and one looked as if I was in the shallows (both around 10 yards wrong). I'd say its accurate enough to pinpoint the location for someone to revisit the spot.

Signal pick up
Once locked on the unit copes well with quite dense trees, valleys etc. I like waterfalls which can involve quite steep and deep river valleys, and it hasn't let me down yet. I do make sure I'm locked on before I move into an area that might have a poor signal.

Time to lock onto signal
The manufacture's web site says Acquisition Time (Open sky, stationary requirements)
Reacquisition 0.1 sec., average
Hot start 1 sec., average
Warm start 38 sec., average
Cold start 42 sec., average
I seldom achieve anything under a minute from cold (i.e. the first time I turn the camera on). The quickest way is to stand still and wait, but can take 3 or 4 minutes. Usually I start shooting and wait for it to catch up which, if I'm moving around, can slow it down even more.
Once its locked on its fine, if I do turn the camera off it locks on again almost instantaneously, even if I've walked some distance.

Battery life
The unit uses the camera battery, there's 3 settings, on, off and auto. Off speaks for itself. On stays on permanently whilst auto turns the unit on only when the camera is on. I tend to leave it in auto. The battery definitely drains quicker when I have the unit attached, but I always carry a spare battery and haven't drained both on a single day's outing yet.

Cost
When I bought my unit there was only one model available, there's now 2 on the website, the basic and the pro. Mine looks like the basic, which is currently listed on the website at $243.00 (US) including shipping. The firm is in Hong Kong, and my order was received very quickly, in good packaging.

As far as I know its only available from the Dawn Technologies website

The di-GPS is available for:
Nikon D2Hs, D2X, D2Xs, D200, D3, D300 & Fujifilm S5Pro
Canon 40D with WFT-E3 and 1D/Ds Mark III with WFT-E2

[huwevans]

Thanks for that, Carrie. I have a hand-held GPS for when I'm out walking, and I use that to simply make a record of position when I want to be sure of finding a location again, but it doesn't tag the image files themselves, of course. I can see the attraction though, if you've not already invested in a separate unit.

[daft_biker]

Thanks for the info Carrie.

Am getting more tempted by a GPS unit for my camera as the bug experts like to know the distribution of different species and they ID things for me.

Although I rarely go more than a few miles so not too difficult to remember what I found where. Within a mile or two is fine for my purposes as these experts are in Belguim and Austria and they just want a dot on a map (and my pics for their websites ).