Memory cards

[NorthernFocus]

...Remind me again who delete the photos one by one instead of inserting it on our laptops to filter which is a great shot and which is not?...

One of the biggest challenges we all face is realizing that not everyone operates in the same context as ourselves.

[george013]

Paul,

I remember that behaviour of deleting files as you describe. Not exactly but roughly.
But what is the difference between "delete all" and "format". With the exception of special files. I mean the format to clean the disk, not the one to prepare the disk for a first use.



By the way, nobody will empty a disk by deleting individual files on the camera. It takes a long time and a lot of button hits: one for select, one for deleting and one or two for confirming. It's a difference between 1 second and a lot of minutes. I don't know a way to select more than 1 file on the camera.

George

[pnodrog]

Paul,

I remember that behaviour of deleting files as you describe. Not exactly but roughly.
But what is the difference between "delete all" and "format". With the exception of special files. I mean the format to clean the disk, not the one to prepare the disk for a first use.



By the way, nobody will empty a disk by deleting individual files on the camera. It takes a long time and a lot of button hits: one for select, one for deleting and one or two for confirming. It's a difference between 1 second and a lot of minutes. I don't know a way to select more than 1 file on the camera.

George

Hi George. A "Delete all" simply goes to the directory and changes the first character of every file name to Hex F5 to indicate the file is no longer in use. The rest of the name, the date it was made, etc and the link to the FAT record remain. This means so long as it has not been overwritten it should be pretty easy to recover.

A "fast" format clears the directory completely destroying all the pointers to the FAT record so the original file although still on the disk/card is effectively lost. Additionally this format also sets all the links and EOF data in the FAT records to zero's to indicate the block(s) they point to is available. However this means that the mapping of which blocks the file was written to and where it ends has been completely lost. I have not found any specific reference to it but I assume a Hex FFF7? entry to a FAT file that indicates a faulty block is left unchanged. (most articles indicate the FAT file is set to zero but if that were the case some of the benefits of the low level or factory format would be lost.) If the disk/card is read and the start block of a contiguous file can be identified the file is possibly recoverable. A non-contiguous file may be scattered across the disk/card and recovering it will be like trying to solve a jigsaw puzzle with no reference picture. Simple text files would probably have the best chance of recovery.

[pnodrog]

An interesting thought. If a camera manufacture (great if it were Nikon) offered a file RAW file save option that kept all files the same length you could force the mapping into blocks to be constant and contiguous provided no other file types were sharing the memory card. If you deleted a file it would just leave a space the right size for it's replacement. Would certainly simplify recovery is ever needed.

[MrB]

I don't know a way to select more than 1 file on the camera.
George

Presumably it depends on the make and model of camera, George.

I have used only Pentax DSLRs and, when I review the images on the rear screen, I can delete the one image being viewed, or mark for deletion those that I don't want and the delete option then removes just those files. Alternatively, in the camera I can chose to delete from the card a complete folder of images in one go.

These are all options for deleting that I use almost daily during my photography after reviewing on the LCD. I keep on the card those images that I want, and transfer them to a PC and backup USB drives when I get home. After transfer and back up, when a card gets more than half-full of images, I format the card in the camera.

I have been working this way for over six years, using Sandisk and Lexar cards without any problems. Perhaps it is naive to think that if the 'delete' option is given in the camera, it should be safe to use. Perhaps I have just been lucky. But I have no intention of changing my ways in this regard.

Philip

[george013]

An interesting thought. If a camera manufacture (great if it were Nikon) offered a file RAW file save option that kept all files the same length you could force the mapping into blocks to be constant and contiguous provided no other file types were sharing the memory card. If you deleted a file it would just leave a space the right size for it's replacement. Would certainly simplify recovery is ever needed.

I looked at some RAW files of mine. They're all about 19MB, D700. What surprised me was that the used disk space was flexible to. Something has changed.
What you want is to put a fixed output from the camera and store that in a predefined array.

George

[pnodrog]

I looked at some RAW files of mine. They're all about 19MB, D700. What surprised me was that the used disk space was flexible to. Something has changed.
What you want is to put a fixed output from the camera and store that in a predefined array.

George

Yep, basically an array but within a FAT structure for maximum compatibility. If the memory card and camera manufactures put their heads together they should be able to figure something out.

P.S. Actually the failure rate is so low they are probably never going to worry about it.

[george013]

Presumably it depends on the make and model of camera, George.

I have used only Pentax DSLRs and, when I review the images on the rear screen, I can delete the one image being viewed, or mark for deletion those that I don't want and the delete option then removes just those files. Alternatively, in the camera I can chose to delete from the card a complete folder of images in one go.

These are all options for deleting that I use almost daily during my photography after reviewing on the LCD. I keep on the card those images that I want, and transfer them to a PC and backup USB drives when I get home. After transfer and back up, when a card gets more than half-full of images, I format the card in the camera.

I have been working this way for over six years, using Sandisk and Lexar cards without any problems. Perhaps it is naive to think that if the 'delete' option is given in the camera, it should be safe to use. Perhaps I have just been lucky. But I have no intention of changing my ways in this regard.

Philip

It shouldn't make any difference if you delete in the camera or on the pc. My workflow is about the same. With using the card reader. I don't trust those small connectors to be used frequently. Risk management

George

[pnodrog]

It shouldn't make any difference if you delete in the camera or on the pc. My workflow is about the same. With using the card reader. I don't trust those small connectors to be used frequently. Risk management

George

The small connector only has 4 or 5 pins that can go wrong vs 50 pins on a CF card...

[Shadowman]

Paul,

By the way, nobody will empty a disk by deleting individual files on the camera. It takes a long time and a lot of button hits: one for select, one for deleting and one or two for confirming. It's a difference between 1 second and a lot of minutes. I don't know a way to select more than 1 file on the camera.

George

Check your manual, you should have a method to delete all images. On my D750 I simply select the Playback Menu key, select the zoom out button until the images show as a tile and then finally calendar, select that date, select the delete button. You can also select a series of photos and delete only those. Also, you can protect images in the series that won't be deleted when you use the batch method. Usually takes a few seconds to delete hundreds of images. For the D750 method is on page 260.

[george013]

The small connector only has 4 or 5 pins that can go wrong vs 50 pins on a CF card...

That's why I mentioned the statement in Manfred's link to keep the cards just in your pocket wouldn't be harmful as the worst advise, special for CF cards. I already had the in-camera card reader replaced, about 160.00E. It's not only the pins, it's the size too.

George

[loosecanon]

He should have added - know which way round the card has to be inserted. Most damage is caused by trying to force a card in incorrectly.
I never delete in camera unless i run out of space - which happens rarely.
I do write to both cards - raw to cf and jpeg to sd. I then copy both to a SS hard drive so raw and jpegs are in the directory for simultanous import into lightroom.
I never delete until i have viewed the image on full screen.

I tried copying from camera, but find it very slow, and the lexar card reader is very fast.

[Manfred M]

I don't trust those small connectors to be used frequently. Risk management

Yet you have to trust those small connectors to record the image your camera has taken on the memory card. I see no difference in the wear and tear on the connectors if you reformat the card in camera or record pictures.

Mechanical damage to the connector pins is going to happen when you install the card in the camera and some level of force is applied.

[george013]

Yet you have to trust those small connectors to record the image your camera has taken on the memory card. I see no difference in the wear and tear on the connectors if you reformat the card in camera or record pictures.

Mechanical damage to the connector pins is going to happen when you install the card in the camera and some level of force is applied.

With those small connectors I mean the usb connectors on the camera. Those I never use. They are small and fixed to a cable. When you want to download directly from the camera, you've to use them.
The CF cards are female. When filthiness is coming in them, you can't get it out anymore. Your CF-connectors in the camera might damage if you try to use such a card. That's why I can't believe he's serious saying one can keep them in the pocket without protection. Not in my pocket. SD cards have slide contacts.

George

[Mike Buckley]

Using USB cables is not limited to downloading images from the memory card, as many accessory items are connected to the camera only by those USB cables. I've never had any trouble using them with my camera or using them with my computer to recharge related devices. I've also never heard of any industry-wide problems connecting USB cables assuming typical precaution and care are exercised.

[george013]

Using USB cables is not limited to downloading images from the memory card, as many accessory items are connected to the camera only by those USB cables. I've never had any trouble using them with my camera or using them with my computer to recharge related devices. I've also never heard of any industry-wide problems connecting USB cables assuming typical precaution and care are exercised.

I just don't trust those little connectors. They work but I'm just afraid when an external force comes up the cable it will have an impact on the camera. Just based on a general experience with them,not specific these.
Google on "micro usb vs mini usb". The mechanical lifetime is an item, even when well used. New for me too.
Beside that, every time finding out the differences between HDMI and USB, or how to plug in the USB-connector in the PC. For me card readers are easier and faster.

Everybody his own workflow and thoughts.

George

[xpatUSA]

The mechanical lifetime is an item, even when well used. New for me too.

Everybody his own workflow and thoughts.

George

Quite right. As an electronic engineer in the past, one of my tasks was to specify connectors for gas turbine control panels. Some of those connectors may still be near you, George, here.

Commercial connectors back then either lacked a coating on the pins or just had a minimal "gold flash" about 0.2um. On the other hand, the British Post Office specified 4um hard gold plating - most impressive.

[george013]

Quite right. As an electronic engineer in the past, one of my tasks was to specify connectors for gas turbine control panels. Some of those connectors may still be near you, George, here.

Commercial connectors back either lacked a coating on the pins or just had a minimal "gold flash" about 0.2um. On the other hand, the British Post Office specified 4um hard gold plating -most impressive.

I don't understand that Facebook link. It's about cows(milk)
For what company did you work?

George

[xpatUSA]

I don't understand that Facebook link. It's about cows(milk)
For what company did you work?

George

I worked an industrial gas turbine manufacturer know then as Ruston Gas Turbines Ltd.

We sold a 3.7 MW turbine-generator to that milk factory - a Ruston TB5000. I think it was a combined heat and power where the turbine exhaust heat was used by the factory. I went to Beilen twice - once with the Sales guys and once to fix a speed governor problem.

Probably my control panels have been replaced by now . . .

[Manfred M]

With those small connectors I mean the usb connectors on the camera. Those I never use. They are small and fixed to a cable. When you want to download directly from the camera, you've to use them.
The CF cards are female. When filthiness is coming in them, you can't get it out anymore. Your CF-connectors in the camera might damage if you try to use such a card. That's why I can't believe he's serious saying one can keep them in the pocket without protection. Not in my pocket. SD cards have slide contacts.

George

Thanks for clarifying. I did not understand this is what you were referring to.

I agree with the need to keep the contacts of the CF cards clean; storing them loose in a pocket or bag is not going to be inherently clean. I suspect that they can be cleaned with compressed air / gas jets, but avoiding contaminants seems to be a much simpler solution.

When it comes to the small USB connectors, I have them on a lot of electronics; phones, tablets, etc. From what I can tell they are quite robust, but would agree that a bit of caution makes sense. I do shoot tethered; either either with a cable connection to the camera or with my CamRanger. These both plug in to the USB 3 port. I either use the strain relief that Nikon ships with the cameras or use a TetherTools strain relief to prevent the cable from pulling out and damaging the port.