on Site Tether issue with Canon EOS 70D

[redged01]

I have set up a long term time lapse project that will run for several years, with the aim of visiting the camera every couple of weeks to collect the images.  I'm using an 'onSite' Tether to power the EOS 70D, which in turn is connected to the mains power supply via a USB adaptor.

The issue is that despite the sustained power being on to the EOS 70D, over a couple of days the battery power indicator on the camera decreases, and eventually the camera shuts down.  Is there a way in which I can avoid this?  Setting in the camera?

Many in advance

redged01

[redged01]

There i no time lapse feature on the 70D. I'll be collecting images every 10 minutes for several years. A remote shutter release, I think, will get around the problem of waking up the camera between shots so the battery will recharge.  It may be that the battery cannot charge if there is a constant drain on it.  

[ebiggs1]

There are two of us that believe it is your power source. Now that's not proof but it does make a strong case for it being the issue.

[redged01]

Thanks very much for your comments.  The plot thickens, as they say.  I have plugged a USB voltmeter and ammeter into the circuit so I can monitor the volts and current supplied to the Tether.  It's rather interesting.  Volts to the Tether stays around 5.05 volts, but the current jumps between 0 and just over 1A transiently.  Almost like a trickle charger.  If I was running low on battery power you might expect the charger to have a sustained delivery of current.  

The next step, I think, is to disconnect the Tether from the USB charger and run the camera just on the built in battery (1200mA) for 30-45 minutes, then plug it back into the USB supply.  I would anticipate that the ammeter would show a sustained current draw.  If its behaviour doesn't change then it is probably the power supply.

[Tronhard]

One point of note.  I just got a chance to check your lens specs and it is designed for crop sensor (APS-C) cameras.  Previously, you could not have attached this lens to a Canon Full Frame body, but the R-series bodies, with the adapter will accommodate an APS-C lens.   I am not sure what body  you are planning to connect this lens to, but if you are hoping to use this with the EOS R7 or R10, the cameras will generate their full sensor capacity.

If you decided to use the lens with a full-frame body like the R, RP, R3, 5 or 6 the lens will connect and work OK but because it projects a narrower area onto the sensor, the sensors will automatically crop the image to that of an APS-C sensor.  That reduces THOSE FF sensors capacity down by a factor of 2.5.  So the FF sensor of the R6 will only produce about an 8MP image.

Again, if you are going to use the lens with a F7 or R10, it will generate the full sensor potential.

[redged01]

Thanks Trevor.  I'm using a EOS 70D which is a crop sensor camera.  I'm not sure how it relates to the current issue.  Perhaps posted on the wrong thread

[ebiggs1]

"One point of note."

Trevor, sorry, but what does that have to do with power loss?

[Waddizzle]

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@ebiggs1 wrote:

"One point of note."

Trevor, sorry, but what does that have to do with power loss?

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Nothing.  I think he simply posted on the wrong thread.  “EF to RF lens adspters”

[normadel]

So your Tether is supplying 5.05 volts. Does that not provide the answer to your problem?

ANY USB power supply only provides 5 volts. Plain and simple. A Canon LP-E6(NH) battery is 7.2 volts, and Canon's and other AC-powered battery replacers provide more. My Wasabi unit says 8.4 volts.

What is it you don't see about your problem? Stop beating a dead horse.

[redged01]

No, you are not correct.  There is a boost converter in the tether relay which will lift the voltage to 7.2V .  If I tried run the camera on 5.05 V the camera would not start never mind go for 2-3 days.  

[ebiggs1]

"No, you are not correct."

Actually he is. 😉 If the voltage goes up, the amperage has to go down. Ohm’s Law says voltage and amperage are inversely proportionally.  The voltage goes up the amperage goes down because you are going to get the same amount of work out if it. It may supply enough for a short, or some period of time, but soon it will catch up with the inadequate output.