[allewellin]

Just wondering how many photos a 64gb memory card would hold when using it in a 14mp camera??
Thanks

[DanBrwn]

There are too many variables to say. File sizes range greatly due to details, highlights, colours and noise. I could get a closer guess if I new what camera you were using, though.

64Gb will be more than enough for most people. I couldn't think of a situation where I would use more

[Happy-Turtle]

I have a 14MP camera too and my 16gb card holds around 2300 pictures, so 64gb could hold around 9200.
Yeah, but it does depend on the file size and etc...

[TheSownRose]

(Original post by Happy-Turtle)
I have a 14MP camera too and my 16gb card holds around 2300 pictures, so 64gb could hold around 9200.
Yeah, but it does depend on the file size and etc...

It's not a direct relationship though, because a 64GB card won't actually have 64GB of space, and nor will a 16GB ... but the 64GB will have lost more than the 16GB.

(Original post by DanBrwn)
There are too many variables to say. File sizes range greatly due to details, highlights, colours and noise. I could get a closer guess if I new what camera you were using, though.

64Gb will be more than enough for most people. I couldn't think of a situation where I would use more

I once had a very large capacity memory card. I got rid of it, it's too easy to not bother with back ups.

[ray-chill]

64GB seems like loads. I have a 8GB card and my camera, on the settings I have, takes 12MB photos and can have around 600 photos. I would assume that as long as you put the photos onto your computer or CDs every so often a smaller, cheaper card may be better.

[alex_hk90]

Back of the envelope calculations:
64GB = 64,000,000,000 bytes = 62,500,000 kiB = 61,035 MiB = 59.6 GiB
In RAW (uncompressed) format (assumes 24 bits per pixel):
14MP = 14,000,000 pixels = 14,000,000 * 3 bytes = 42,000,000 bytes = 40.0 MiB
Therefore, (minimum) number of photos:
64,000,000,000 / 42,000,000 = (approx.) 1,500 photos

But if you use JPEG (compressed) format, then it might be more like 4 MiB per photo, so it will probably be closer to 15,000 photos.

Of course you might want to reduce the estimates by at least 10% to account for unknowns like partition space on the card, extra data produced/saved by the camera, etc.

[DanBrwn]

(Original post by TheSownRose)
I once had a very large capacity memory card. I got rid of it, it's too easy to not bother with back ups.

Same, I use 8Gb for wondering and 16gb for actual shoots. Never fill the 16

[evening sunrise]

(Original post by alex_hk90)
Back of the envelope calculations:
64GB = 64,000,000,000 bytes = 62,500,000 kiB = 61,035 MiB = 59.6 GiB
In RAW (uncompressed) format (assumes 24 bits per pixel):
14MP = 14,000,000 pixels = 14,000,000 * 3 bytes = 42,000,000 bytes = 40.0 MiB
Therefore, (minimum) number of photos:
64,000,000,000 / 42,000,000 = (approx.) 1,500 photos

But if you use JPEG (compressed) format, then it might be more like 4 MiB per photo, so it will probably be closer to 15,000 photos.

Of course you might want to reduce the estimates by at least 10% to account for unknowns like partition space on the card, extra data produced/saved by the camera, etc.

40MP sounds a bit over the top.


12MP RAW uncompressed 12 bit gives 19mb
12MP RAW uncompressed 14 bit gives 25mb

The 16mp files are a bit larger peaking at around 33Mb.

The reason the simple calculations give an over estimate is that the raw files have not been demosaiced. So there is only one colour value per pixel, once demosaiced there are three colours per pixel.

I don't use uncompressed RAW my self. It beats me why my cameras have uncompressed and lossless compressed as well as compressed recording modes for RAW.

For most shooting I use 14 bit lossless compressed RAW. For sports/wildlife action I use compressed RAW 12 bit, to maximise the buffer capacity.

Cameras such as the D90, D5000, D3n00 record compressed RAW.

[Tootles]

(Original post by allewellin)
Just wondering how many photos a 64gb memory card would hold when using it in a 14mp camera??
Thanks

About 18,000 or so I think, given an average size of 3.5MB per image and the (admittedly unformatted) size of 65,536MB of the card. Definitely more than 15,000 anyway.

[alex_hk90]

(Original post by evening sunrise)
40MP sounds a bit over the top.


12MP RAW uncompressed 12 bit gives 19mb
12MP RAW uncompressed 14 bit gives 25mb

The 16mp files are a bit larger peaking at around 33Mb.

The reason the simple calculations give an over estimate is that the raw files have not been demosaiced. So there is only one colour value per pixel, once demosaiced there are three colours per pixel.

Won't using those kind of formats (12 bit, 14 bit) lose some of the original information (the reconstruction won't be perfect)? I always thought it was 8 bits per colour so 24 bits per pixel in uncompressed RAW format.

[TheSownRose]

(Original post by alex_hk90)
Back of the envelope calculations:
64GB = 64,000,000,000 bytes = 62,500,000 kiB = 61,035 MiB = 59.6 GiB
In RAW (uncompressed) format (assumes 24 bits per pixel):
14MP = 14,000,000 pixels = 14,000,000 * 3 bytes = 42,000,000 bytes = 40.0 MiB
Therefore, (minimum) number of photos:
64,000,000,000 / 42,000,000 = (approx.) 1,500 photos

But if you use JPEG (compressed) format, then it might be more like 4 MiB per photo, so it will probably be closer to 15,000 photos.

Of course you might want to reduce the estimates by at least 10% to account for unknowns like partition space on the card, extra data produced/saved by the camera, etc.

I'm not sure that's right... The raw files from my 21.1MP camera are peaking at about 33MiB.

[alex_hk90]

(Original post by TheSownRose)
I'm not sure that's right... The raw files from my 21.1MP camera are peaking at about 33MiB.

That assumes 24 bits per pixel and no compression (not even lossless compression).

[evening sunrise]

(Original post by alex_hk90)
Won't using those kind of formats (12 bit, 14 bit) lose some of the original information (the reconstruction won't be perfect)? I always thought it was 8 bits per colour so 24 bits per pixel in uncompressed RAW format.

I am afraid you have been totally mislead.

12 bit raw results in 36 bits per pixel not 24, and 14 bit results in 42 bits per pixel. But every camera sensor is a Bayer array (actually has a bayer array filter infront of the sensor), there are not equal numbers of photoreceptors dealing with the three colours. Demosiacing is able to generate the missing two colours (three on a Sony F828 which has a 4 colour sensor) for each pixel based upon the values in the photo receptors.

After demosiacing a 12 bit raw file has 36 bits for each pixel, 12 bits per colour, a 14 bit raw 42 bits per pixel, 14 bits per colour. If you then save as a 16 bit TIFF all this is recorded along with a couple of extra bits of information per pixel. If you generate a jpeg or 8 bit TIFF then all that extra information above is lost as afterwards you only have 24 bits per pixel (8 bits per colour).

The reason your "common sense" calculation over estimates the size of raw files, despite the fact you mistakenly assumed only JPEG levels of colour detail, is because of the nature of a bayr array and the demosiacing that takes place.

As I mentioned before RAW on lower end models is compressed as well. On more expensive models you get the choice of uncompressed, lossless compressed and compressed, and 12 or 14 bit. uncompressed is just about redundant these days as the in camera processors are so powerful, the little bit of extra effort to apply the lossless compression does not matter even in burst mode shooting, file size for reasons of buffer capacity is far more of a consideration. Which is why for sports / wildlife action I switch both bodies to 12 bit compressed RAW, where as I normally shoot 14 bit lossless compressed, and never use uncompressed.

I hope that helps.

[alex_hk90]

(Original post by evening sunrise)
I am afraid you have been totally mislead.

12 bit raw results in 36 bits per pixel not 24, and 14 bit results in 42 bits per pixel. But every camera sensor is a Bayer array (actually has a bayer array filter infront of the sensor), there are not equal numbers of photoreceptors dealing with the three colours. Demosiacing is able to generate the missing two colours (three on a Sony F828 which has a 4 colour sensor) for each pixel based upon the values in the photo receptors.

After demosiacing a 12 bit raw file has 36 bits for each pixel, 12 bits per colour, a 14 bit raw 42 bits per pixel, 14 bits per colour. If you then save as a 16 bit TIFF all this is recorded along with a couple of extra bits of information per pixel. If you generate a jpeg or 8 bit TIFF then all that extra information above is lost as afterwards you only have 24 bits per pixel (8 bits per colour).

The reason your "common sense" calculation over estimates the size of raw files, despite the fact you mistakenly assumed only JPEG levels of colour detail, is because of the nature of a bayr array and the demosiacing that takes place.

As I mentioned before RAW on lower end models is compressed as well. On more expensive models you get the choice of uncompressed, lossless compressed and compressed, and 12 or 14 bit. uncompressed is just about redundant these days as the in camera processors are so powerful, the little bit of extra effort to apply the lossless compression does not matter even in burst mode shooting, file size for reasons of buffer capacity is far more of a consideration. Which is why for sports / wildlife action I switch both bodies to 12 bit compressed RAW, where as I normally shoot 14 bit lossless compressed, and never use uncompressed.

I hope that helps.

Thanks for the info. But unless I've misread the Wikipedia article, it seems that demosaicing is not a lossless process (i.e. it does lose some information compared to capturing in the full 36 bits or 42 bits per pixel). So do high-end cameras have an option of capturing in these full bitrates or do you have to go through the demosaicing process and lose some information as a result?

EDIT: More Wikipedia suggests very few cameras do this. Thanks again.

[evening sunrise]

(Original post by alex_hk90)
Thanks for the info. But unless I've misread the Wikipedia article, it seems that demosaicing is not a lossless process (i.e. it does lose some information compared to capturing in the full 36 bits or 42 bits per pixel). So do high-end cameras have an option of capturing in these full bitrates or do you have to go through the demosaicing process and lose some information as a result?

EDIT: More Wikipedia suggests very few cameras do this. Thanks again.

I am not sure the term lossless or not is applicable as the process is one of creation, one might consider it to be an imperfect creation process. It cannot lose what it never captured.

The point is that all modern digital sensors demosiac, certainly every Nikon, Fuji, Panasonic, Pentax, Sony, Canon whether you pay 100 quid for it or 4.5K. But my mates medium format (needs a truck to move it) does actually capture three complete images for every frame, one for each colour, but a new digital back for it cost him 30K, but it is his livelihood so that is Ok.

How you concluded that not many camera's demosiac is a mystery, I had to check the article because I never use the wiki as an authoritive source or reference.

But we are digressing, the point is your calculations for the size of raw files are both theoretically wrong and do not match the actual size of uncompressed raw files obtained by those of us actually shooting in uncompressed RAW and I pointed out why the calcuation is wrong and why it does not match the real world results.

So there we are the OP now knows the reality and the correct sizes and why.

[alex_hk90]

(Original post by evening sunrise)
I am not sure the term lossless or not is applicable as the process is one of creation, one might consider it to be an imperfect creation process. It cannot lose what it never captured.

The point is that all modern digital sensors demosiac, certainly every Nikon, Fuji, Panasonic, Pentax, Sony, Canon whether you pay 100 quid for it or 4.5K. But my mates medium format (needs a truck to move it) does actually capture three complete images for every frame, one for each colour, but a new digital back for it cost him 30K, but it is his livelihood so that is Ok.

How you concluded that not many camera's demosiac is a mystery, I had to check the article because I never use the wiki as an authoritive source or reference.

Sorry, I was unclear - I meant that not many current popular cameras do not use this process.

(Original post by evening sunrise)
But we are digressing, the point is your calculations for the size of raw files are both theoretically wrong and do not match the actual size of uncompressed raw files obtained by those of us actually shooting in uncompressed RAW and I pointed out why the calcuation is wrong and why it does not match the real world results.

So there we are the OP now knows the reality and the correct sizes and why.

Indeed. Though in reality I would expect that they would use JPEG instead of RAW anyway, but it does at least raise the minimum number they should expect to be able to store on their memory card.

[evening sunrise]

(Original post by alex_hk90)
Indeed. Though in reality I would expect that they would use JPEG instead of RAW anyway, but it does at least raise the minimum number they should expect to be able to store on their memory card.

Indeed, 14mp could be anything from a D3100 to a S2960.

[HughTFall]

I agree with @ray-chill here! I stored my fresh photos in my computer in order to minimize getting in the memory's maximum capacity. 12 Mb is equivalent to 600 photos.

[DanBrwn]

(Original post by HughTFall)
12 Mb is equivalent to 600 photos.

Not necessarily

[HughTFall]

@DanBrwn, yes it could be not necessary to have 600 photos on a 12mb memory, but I have calculated it same as @ray-chill. What are your thoughts about this?