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Sunday, 15 July 2007

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I been using ImageIngester Pro since last August when I switched to the Mac platform and could no longer use BreezeSystems Downloader Pro.

I've found ImageIngester Pro to be an exceptional product that is very well supported and frequently updated by Marc. He is quick to address problems and his website is set up to gather user feedback on future enhancements.

Marc has specifically aimed this product at those interested in Digital Asset Management, and in particular, those practices laid out in Peter Krogh's book, "DAM: Digital Asset Management For Photographer". The program supports workflows from the simple (for which the free version is adequate) to the very complex, including support for multiple cameras used on assignment.

I would change items 1 and 2 to say the following:
"Use the camera's format command to delete all previous images. Do not delete any images from the card in any other way."

For item 3:
"Do not make any changes to the card while it's connected to your computer. Let the camera be the only device that makes changes to the card.

Re: ImageIngester: Note that Lightroom can convert and make back up copies of images when importing them from a camera.

Hi MIke:

I used to use ImageIngester all the time and found it to be a very nice piece of software. I switched from iView Media Pro to Lightroom and now I don't need to use ImageIngester at all since the functionality of ImageIngester is in Lightroom. My personal preference would be to go with Lightroom though ImageIngester works fine for bringing images into the computer.

I hope you are feeling better. BTW, your photo of the street light is hanging over my wife's bureau in our bedroom. It looks great!

Cheers,

Richard Ripley

These rules are good to follow. :) It's always nice to be reminded though. As far as that software goes, I think Adobe's lightroom essentially does the same thing, plus includes the ability to make the various corrections most photographers would be using (as PhotoShop is nice, but almost too powerful for basic editing for production purposes).

I've never really understood these suggestions. Any normal card is formatted as FAT32, which has been around for more than a decade and is supported by any device a normal person is going to use. Yes, it's prone to fragmentation, but otherwise, it's about as simple as you can get. Format it once in a while to clean up the fragmentation, but every time? And only from the camera? Pffft.

These rules are superstition. Yes, cards fail. But there are far more rational explanations than "I deleted pictures from my computer, not the camera!"

How about these rules:

1) protect the cards from static electricity. Store in an anti-static bag.

2) protect from heat. don't leave your camera bag in the car on a hot day.

3) protect from humidity. particularly, taking cold-and-dry cards from your air conditioned car out into hot-and-humid environments to shoot seagulls or whatever.

I bet breaking *those* three rules have caused more card failures than anything else.

Apropos number 3 and not writing to the card from the computer - what about writing to the card when doing a firmware update on Nikon cameras (maybe others as well)?

And clearly, FredW's comments were about making pictures easy to *recover* if there's a problem. But I've heard them as general suggestions for *preventing* failures, which is pretty crazy.

And even for dealing with failures, they don't make a lot of sense. 2, maybe, but even that's unlikely.

One ImageIngester feature that's relevant to this discussion is that it can automatically verify the integrity of ingested images at ingestion time, while the card is still at hand. If there's any problem, the card is still available for various rescue attempts.

--Marc

If you delete files on a windows machine , they get moved to an invisible directory that some cameras can't see or delete and you end up having to reformat anyway. Likewise , Macs create resource forks and the like which some some cameras choke on. Lots of cameras really aren't expecting anything other than what they wrote themselves.
Another thing is that formating is far faster than erasing the files in the camera. Who has time to erase files? Reformatting regularly is good for the longevity of the flash memory.

See

www.embeddedfreebsd.org/Documents/WPaperWearLevelv1.0.pdf

worst case analysis

"In the worst-case application, data will be written as single sectors to random addresses across the card. These single sector writes will exercise the erase pool more rapidly, requiring the system to perform a “garbage collection” operation to free up new blocks for subsequent write operations. At the extreme, each single sector write would cause one block to be programmed and erased. As a typical block size is 16kB or 32 sectors, the amount of wear is increased by a factor of 31 since 32 physical sectors are written and erased for each sector the host writes.
Spreading this wear across the erase pool results in an effective 1/30 usable lifetime. This case is an extreme example and is only included to show the range of application dependence. This result is comparable to other vendor’s cards based on memory with a 16kB erase block"

The main reason for not writing to the card while it's connected to the computer is that, until you've offloaded and archived the images elsewhere, it's your authoritative source in case of screwup.

What I disagree more with is the idea that one should just shoot through a card without deletion at source. Hey, if you want to chimp, go for it. If a shot looks bad enough to be objectionable on that LCD it'll probably look even worse on the proper screen, so save yourself the first level of image-selection earlier if you want.

i would really like to get a better sense of where these rules come from. fwiw, i do almost always reformat in the camera; for some reason that seems to make sense to me, after all the first priority is to make sure the camera has a good relationship with the card. but, while i don't delete individual shots a lot as i go in camera (as a rule i figure that i might learn something from even the bad ones by examining them later on the computer, and besides, you just don't know what you really have looking at the camera screen), i do sometimes--some of them are just embarrassing, and besides i am constantly firing off exposure tests where i have no interest in the image itself whatsoever. it makes no sense to me that deleting individual shots is going to pose a risk to the card integrity (although for the purposes of data recovery, perhaps it could make a difference).

as to not making changes from the computer--sometimes i use my cf cards as portable hard drives with my macs. so far so good--and i don't see why reformatting the card subsequently in the camera wouldn't solve any issues those files might otherwise cause.

but the point is, this is a case where i would like to get info from someone who really knows what is going on. mike or ctein, would you be willing to do a bit of reporting on this, maybe email the makers of the various file recovery utilities and ask the programmers what constitutes best practices? no offense to any who've posted so far, but the originating comment was quite up-front about being no expert. this sounds like a case where expert opinions really trump rumors circulating on the internet.

On ImageIngester: I bought it mainly because it can read a GPS tracklog, and write Latitude, Longitude and Altitude information to the image files in the process of copying them from card to computer. At the moment this capability is only in beta but, in my tests so far, it has worked well. It works with Canon raw files (unlike RoboGeo), and installs and works painlessly on Windows (unlike gpsPhoto.pl, which I could not get to work).

Since we're entering into the territory of unsubstantiated folklore, I'd like to offer my own:

1. Follow the instructions that came with the camera. The manual for mine says to format the card in-camera.

2. Use larger cards to minimize card swaps. Flash memory cards are pretty robust but not immune to problems from continual handling.

3. If the camera supports USB2 transfer speeds, use the provided cable to transfer files to your computer. Depending on what/how you shoot, you may find you rarely have to remove the card.

4. Flash memory supports a finite number of writes so if the card has been heavily used, get rid of it and buy a new one ... even if it's working fine. Contrary to popular belief, each image written to the card doesn't just update it sequentially, it also updates the directory and file allocation tables (which are roughly in the same area). It's the continual writes to these that are likely to cause the card to fail.

5. If the camera has reliable firmware there's no impediment to deleting in-camera ... but be mindful of the point above as deletes are writes as well. Checking the image's histogram and re-shooting (if possible) will avoid disappointment later. The best you can hope for from automated exposure is something in the ballpark.

6. Don't worry and enjoy your camera.

The filesystem used - fat32 - is in fact not standardized. There are many corner cases in the available descriptions, and so not all implementations act the same way in all cases. But any one implementation, like the one written for your camera by the developers, is probably pretty well tested with itself and so limiting yourself to using one device for all writing to the card will avoid a lot of problems. This is probably the main reason for the rules above.

I would state the rules as:

* only write files, delete files and reformat the card with the camera. Don't let any other application write to the card - and that includes things like not using an image viewer on the mounted card since they tend to want to write thumbnail data and other stuff.

* Format the card once in a while - once every 20-30 times you've filled it, say - but not every time, since you risk end up rewriting the same area on the card with filesystem data every time, which shortens the lifetime of the card.

* Most important is Mike's suggestions: cards may be hard and plastic and have no moving parts, but that does not mean they're indestructible, Don't abuse them.

............ I have been breaking all those rules for yonks it is not even unknown for me to have a word file, images from other cameras, procedded photoshop images etc,,,,,,,,,,,,,, never had a problem

Don't understand why there should be a problem with deleting files in-camera. I routinely do this when on a trip - for example, over lunch or on public transport. It means less work sorting thru the images in Lightroom when I get home.

Could someone explain to me why this would cause a problem?

A good app to use will be PhotoMechanic, http://www.camerabits.com/pages/PM4.html

Sorry folks, if it will save me a precious few minutes of being in the office at all hours of the night I'll happily start getting rid of bad shots in camera. I'll take the risk, as you say: cards are cheap.

I delete photos which I know are bad in camera if I have a free moment. Importing, converting and then removing photos I know I won't be keeping seems an unnecessary waste of time. Especially if the photo was bad due to carelessness or inexperience -- "oh yeah, that's where I took ten shots in a row with the camera accidentally set to manual" -- meditating on missed shots can really bring down the high of the great ones.

"Macs create resource forks" on FAT32-based cards? That is doubly false. First, Macs don't create resource forks any more, though they will still read them if present. Second, FAT32 is a single-fork filesystem -- there's simply no way to create a resource fork on it, even if a program tried.

The cautions to:

1) Always format in-camera
2) Never delete anything in-camera until downloaded

...are really in direct conflict with each other. If the camera is the safer file system manipulator, then what possible harm could there be in deleting flubs on the fly? Possibly a good rule for avoiding photographer screw ups but technically unnecessary.

Also: when you use the computer to tell the camera to delete images, the CAMERA deletes the images, not the computer! So erasing the card through software that issues commands to the camera is no different than doing it through the camera interface.

HOWEVER...I don't think it's ever wise to perform file system changes through a card reader. The only time I've had problems is when I've done that.

While Lifetime Warranty can just mean that it's cheap for them to replace it, it does seem that the life of these cards is longer than I thought so I'd like to retract my statement that one should ditch old but working cards. In practical terms though, cards are cheap and at current capacities offer nearly limitless shooting so maintaining the same electrical and logical environment is a safe and practical measure ... for many but obviously not all users.

Stephen

I know this will sound nuts: But with memory prices as low as they are now, the idea might actually have some merit. I have one friend that never deletes or formats a card. When it is filled up, she labels it with a date, stores it away, and starts another card. When she had a hard drive crash recently, it actually proved to be an adequate backup system. :-)

Dear CJ,

It's not nuts as a short-term 'belt-and-suspenders' policy, but flash RAM data is not long-term stable the way hard drive and CD/DVD data is. Your friend should not rely on this for multi-year storage.

pax / Ctein

Dear Paul,

You misunderstood the admonition to not delete in-camera. The import was one should not delete individual files AT ALL, not even in-camera, where the software and hardware can be presumed to be most compatible.

I don't know that I believe that, but it's not at all in conflict with recommending formatting in camera.

Also, most people are using card readers and not moving files directly from the camera to the computer. So your point about the computer telling the camera what to do (even if correct, which I have some questions about) is not the situation most workers are dealing with.

pax / Ctein

I don't understand. From the three suggestions above, I only do the first one. And I do that because my camera has shortcut for doing just that by pressing two button simultaneously. So it is easier than having to go into menu and deleting the images.

I delete image (file) in camera regularly.

I write the card from my computer regularly.

It never failed. If in the future the card fail, I am pretty sure it will not have anything to do with
deleting image (file) from camera and writing the card from computer.

Damn sure.


The one time I had card corruption, I discovered it was still readable by the camera, but not in a card reader. So I dumped the card filesystem to a big file using dd, and kept it in the hope that one day I'd be able to rescue the pictures. Four years later, I discovered recoverjpeg, and was able to extract all the images. The card still works fine; perhaps I'd had a bad write due to a battery glitch?

Much fuss over nothing. Sorry but the card is never formatted, all that happens is the divice sends a format command to the card and it clears the file lisings and space used to 0. Simple and safe :)

Where you delete files is your own personal choice...

Enjoy

Victor

I have been in the computer business since 1981. I have fixed computers, retrieved data from hard drives after the data was thought to be lost. This conversation is a lot of do about nothing.

1. Formatting does not remove data. Hence why we can retrieve data after it has been deleted. Why we can unformat storage devices and retrieve information that was supposedly lost.

2. Writing to a storage device from two separate sources, ie. camera and computer should have no effect on the data in the device. You might run into issues where the camera assumes there is more space available than there actually is, but that would be unusual. The camera or computer should be able to tabulate the free space without any issues. Keep in mind also, that you can store data from the computer in a different folder than the one used by the camera, in which case the camera would not get "confused" by the extra data.

3. The tech support people at ontrack.com have the following advice:

"Other than not removing the card when the device using it is powered on, not letting the device use the card get low on power and following the manufacturer's instructions while using the card, the divide which uses the card and any card readers (and of course the backup guide above), we don't have a best practices guide for digital media storage."

Relax. Use your common sense. Take your pictures. Enjoy.

Interesting how myths get propagated so quickly these days. Remember how we have been told for years that camera exposure meters are calibrated to 18% gray? Of course no such calibration ever existed.

I always format my cards in my pc. That way I can give each a different name so that, when I am working with a lot of files after an event (3x 4GB cards and a couple of 2GB cards) I don't get lost on which card is which while I have 3 plugged in at the same time.

Modern cameras work with the FAT file system. FAT16 for cards up to 2GB and FAT32 for cards bigger than 2GB. If you format your card in your computer you can perform a full format which can repair some card problems whereas in camera formatting will not.

Why don't we create a list of cameras that refuse to work with cards that have been properly formatted in a computer. Then we will know which cameras to avoid.

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