This is an extension of the former post about the OTG https://www.nikoncafe.com//forums/viewtopic.php?t=4252&highlight= I wanted to test the OTG, so I charged the OTG and let it sit for a few days. With a 1GB CF Card full (RAW+JPG) I connected the OTG directly to the D70 and started the copying. At an 1h:50m the battery in the OTG was depleted and the unit shut down. I put the AC adapter into the OTG to charge and run on A/C. Then I connected my SanDisk Imagemate CF reader to the OTG and started the copying. Copying was finished in something over 5 hours. There were 314 files copied. I did not repeat the test copying directly from the D70 with the OTG AC power connected. It seems that it takes as much time whether directly connected to the D70 or a Card Reader. That means that the speed of copying is determined by the speed of the OTG. I know from my other mini-hard drive, that these do run a lot slower than standard PC HDs. My computer copied the images to my PC's HD in just a few minutes..... So, the OTG works, but it is slow.