Using camera USB to DL images - why the hate?

[charleski]

Ok, it's a slightly jocular title, but it expresses a feeling I've had for a while. There seems to be a general consensus that downloading images through your camera's USB connection is evil (I remember chuckling at the way Michael and Jeff munched garlic and made cross signs concerning this on the LL LR tutorial).

I can appreciate that if you come back from a shoot with a brace of cards to download then your best option is a dedicated reader (ideally a FW800 one such as the Sandisk, Rob Galbraith's site shows very little difference in general between ExpressCard solutions and USB2 [edit: Jeff: ExpressCard is definitely *not* faster than FW, and *definitely* not 'bus speed', sorry, but I had to say that]). But if I've only taken 200 pics or so I don't see that I'm losing anything by simply fishing the USB cord out of my camera bag (where it lives in case I ever want to tether on location) and dling through the camera's interface.

It runs the battery down? Big deal, my Canon has gone 1500+ on a single battery and I always rotate batteries and recharge the used one(s) after a shoot anyway, LiIon bats like to be full. I can't think of any other coherent reason not to use the camera as a dl interface (apart from accessory manufacturers wanting to sell you more gear).

If I've missed anything important, please instruct, but this looks to me like a balloon that needs to be punctured.

[dalethorn]

Depending on what year your camera manufacture is might determine how fast it is.  I've seen plenty of "USB-2" interfaces that weren't. With CF cards, there's no risk pulling them and DL'ing from a card reader, as long as you're careful putting the card back into the camera so you don't bend the pins. With SD cards, I wouldn't recommmend pulling them ever, since the contacts are exposed.

[DarkPenguin]

The card slot is a point of wear.  So you run 10 cards through your camera and then have to run them through the camera again to download them.  That's pretty much doubling the wear.  Card readers tend to be cheap so it doesn't really matter if you destroy them.

Edit: Added the word "again".

[Luis Argerich]

What?

The card slot is a point of wear.  So you run 10 cards through your camera and then have to run them through the camera again to download them.  That's pretty much doubling the wear.  Card readers tend to be cheap so it doesn't really matter if you destroy them.

Edit: Added the word "again".

[charleski]

The card slot is a point of wear.  So you run 10 cards through your camera and then have to run them through the camera again to download them.  That's pretty much doubling the wear.  Card readers tend to be cheap so it doesn't really matter if you destroy them.

Yes, very good point, though it works both ways.

If you have a shoot where you run through multiple cards, then once those cards are out of the camera, it's best to DL them through a different interface. But in these days of 8, 16, 32GB cards, I find it very often that I get back to base without needing to change the card (maybe I should shoot more pics to fill it up:) ). In that case, removing the card to insert it in a different reader for DL and then reinserting it in the camera is needlessly increasing the wear on the camera's CF connection, far better just to leave the card in-camera and DL the pics through the camera's own USB interface.

I'd absolutely agree that those who need to use multiple cards (and there are some situations where this is the best strategy, though those mostly relate to photojournalism) should ingest those cards to their PC via a separate reader. But a 32GB card goes a long way on a high-res fullframe dSLR, why incur ejection/insertion wear on the camera's CF connection instead of just DLing the images through the camera's own USB interface?

[DarkPenguin]

I have a broken battery holder on my G9.  So I always download through the camera so I don't wear out the door.  (Which is the only thing holding the battery in.)  Otherwise I tend to pull the card, put a fresh one in the camera and then wipe the first one only after I've downloaded it and the Mozy backup has run.  Until the backup has run the card itself is the backup.

Another thing comes to mind.  In the winter I tend to pull the CF cards while I'm still outside.  Then while the camera gear is slowly returning to room temperature in the house I can download my pics without worry of condensation on the equipment.

Also if you are going to be dumping the images to a laptop and an image tank you'll likely pull the card, put it in the tank and pull the images down from the tank to the laptop.  You can go the other way but I like the data verification on my image tank.

Just some thoughts.  I don't think it matters one way or the other but there are a few reasons why one would want to use a card reader.

[Jonathan Wienke]

Yes, very good point, though it works both ways.

If you have a shoot where you run through multiple cards, then once those cards are out of the camera, it's best to DL them through a different interface. But in these days of 8, 16, 32GB cards, I find it very often that I get back to base without needing to change the card (maybe I should shoot more pics to fill it up:) ). In that case, removing the card to insert it in a different reader for DL and then reinserting it in the camera is needlessly increasing the wear on the camera's CF connection, far better just to leave the card in-camera and DL the pics through the camera's own USB interface.

Actually, you're just trading wear on the card interface for wear on the USB interface. You aren't gaining any real advantage. The card interface wear issue is way overblown though. I've shot close to 150,000 images with my 1Ds and 1D-II bodies with zero problems in that department.

Using a card reader is faster, more reliable, and doesn't tie up the camera while the transfer is taking place. If you shoot enough to fill more than one card, a card reader is a much better option. If not, it's no worse than downloading direct from the camera.

[charleski]

Actually, you're just trading wear on the card interface for wear on the USB interface. You aren't gaining any real advantage. The card interface wear issue is way overblown though. I've shot close to 150,000 images with my 1Ds and 1D-II bodies with zero problems in that department.

It is actually true that the durability spec for USB connectors is far lower than CF (1500 insertion/ejections compared to 10000), though the failure of a camera's CF connector is a catastrophic event whereas failure of the USB2 connector would merely be a nuisance. The CF interface is dependent on having properly robust keying channels, and most of the problems with bent pins are a result of the card not being lined up correctly before contact. I agree, however, that with properly-engineered interfaces the issue of wear should not be a problem in either case.

Using a card reader is faster, more reliable

Faster? Only if you're using the Sandisk FW800 interface. Rob Galbraith's tests on USB2 CF readers show a wide variation in speed for the same card, with the best of them peaking at around 35MB/s. While I've been unable to find any tests of in-camera CF read speeds, a modern camera with a UDMA interface is capable of writing to CF at up to 33MB/s, so it's difficult to imagine the read speed being lower. If you're using an older camera then you may see a benefit in using a separate USB2 reader, but that is dependent on using a card that's over-specified for your camera.

As far as reliability goes, if we've discounted the issues of connection wear and battery life then there are no other points of failure which would would discriminate between the two methods.

So if you have a large-capacity card that holds all the images from a shoot, then you gain no benefit by using a separate USB2 card reader and might as well just hook up your camera to download from there.

[jjj]

I've had so many isues with card readers that this thread has prompted me to consider using the Camera USB, which I'd forgotten about.
CRs seem to either be pathetically slow to start with or slow down for no real reason. Or simply stop working. It's not the computer being slow as if I stick another CR in, it works fine. Then one will be fast with the Mac and slow with the PC and then slow with the Mac !?!
The worst I've ever experienced was a SanDisk PMCIA CR which was slower than dial up and which only showed it's slowness once I was on location, where finding another CR was challenging!

[JeffKohn]

Faster? Only if you're using the Sandisk FW800 interface. Rob Galbraith's tests on USB2 CF readers show a wide variation in speed for the same card, with the best of them peaking at around 35MB/s. While I've been unable to find any tests of in-camera CF read speeds, a modern camera with a UDMA interface is capable of writing to CF at up to 33MB/s, so it's difficult to imagine the read speed being lower. If you're using an older camera then you may see a benefit in using a separate USB2 reader, but that is dependent on using a card that's over-specified for your camera.

I wouldn't make any assumptions about the read speed of the USB interface based on how fast the camera can write images to the card. Directly reading/writing to the card while shooting is not the same thing as using the USB mass storage interface.

[Jonathan Wienke]

I wouldn't make any assumptions about the read speed of the USB interface based on how fast the camera can write images to the card. Directly reading/writing to the card while shooting is not the same thing as using the USB mass storage interface.

The only way to know is to test with your card, reader, and camera. My experience is that a good card reader is generally faster than downloading from the camera. YMMV depending on your exact combination of hardware.

[adam z]

I lost my card reader and since I haven't been shooting a lot in the last few months I have been using the camera usb cord. I find it much slower than the fairly cheap card reader. I will certainly be buying a new card reader soon.

[seangirard]

No need to pull the camera out of the bag, find a spot on the desk, etc.

[Jack Flesher]

Wow.  Camera connection is a PITA, usually have to load the camera software and the camera connection is almost always slower than a dedicated reader.  Readers are 1) CHEAP and 2) fast, and 3) did I mention cheap?   I even have one by IOGear that is a essentially a USB hub with built-in universal reader slots for every card that is pretty fast.  My Lexar dedicated for SD and CF is a tad faster and the one I normally use unless I have so many cards I want to DL in parallel...

[Paul Sumi]

Wow.  Camera connection is a PITA, usually have to load the camera software and the camera connection is almost always slower than a dedicated reader.

Agree 100%.  Also, up until recently, most camera USB connections were USB 1.1 so were molasses-slow to begin with.  Okay for small JPGs, but forget it for RAW.

Paul

[charleski]

I wouldn't make any assumptions about the read speed of the USB interface based on how fast the camera can write images to the card. Directly reading/writing to the card while shooting is not the same thing as using the USB mass storage interface.

The interface is limited by its write speed. All flash memory is subject to the same constraints. The read speed will always be greater than the write speed. 'Directly reading/writing to the card' is using the same interface exposed via the USB port, the difference will be minimal and you certainly won't see a difference between using a modern camera's USB interface compared to that provided by an independent card-reader that's running on the same CPU.

Sure, if you have an ageing camera with an old interface, then a more modern USB CF reader may beat it. But for a modern camera there's very little point.

Camera connection is a PITA, usually have to load the camera software

Really??? I just plug in my Canon and the software automatically loads. I just have to click one button and the RAW files are automatically sorted and downloaded to the correct directories. In terms of ease-of-use the Canon Utility far surpasses downloading from a card-reader.

The notion that separate CF readers are somehow superior is based on old technology that doesn't take into account the current situation.