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StephenL
2nd September 2009, 09:16 AM
I've just bought two identical new Kingston 8Gb CF cards from Picstop (a reputable source) for my E-3 and E-620.
Both cameras are at present set to shoot Raw only, and I have formatted each card in its respective camera.
Now, the E-3 shows a potential number of shots available on the card as 462, whilst the E-620, which has a greater pixel count, shows more at 535. I would naiively have expected the reported available shots to be the other way round. I realise that these figures are never anywhere near accurate, but has anyone any thoughts as to why such a large discrepancy?
Has the E-620 a better algorythm for calculating shots left? Does it compress the Raw files better/differently/at all? :confused:

theMusicMan
2nd September 2009, 01:13 PM
I see where you are coming from here Stephen, but I am not sure that RAW image size is proportional to the number of pixels in the image. RAW format is all about data... and not image size. Yes, of course, the larger the image size in pixels, the more data there is about that image, but not perhaps in a direct proportion.

I am unsure if the sensors in the E-3 and E-620 are the same, but I'd hazard a guess that the E-3 will possibly yield more RAW data than the E-620, hence the slightly larger file size?

Just a thought...

EH1
2nd September 2009, 01:17 PM
Just out of interest what do the camera`s display if you set them both to jpeg ?

theMusicMan
2nd September 2009, 01:18 PM
Just out of interest what do the camera`s display if you set them both to jpeg ?
Oooh, great question! I must try this with my E-3 and E-520 later too!

StephenL
2nd September 2009, 01:32 PM
Set to Large Superfine, the E-3 yields 1010 (or 999 on the top plate as that LCD can only display 3 characters in that field!), and the E-620 is 837. Now that's more like the sort of ratio I would expect, not that from previous experience I expect any of those figures to bear anything close to reality!!

Just out of interest what do the camera`s display if you set them both to jpeg ?

theMusicMan
2nd September 2009, 01:35 PM
Set to Large Superfine, the E-3 yields 1010 (or 999 on the top plate as that LCD can only display 3 characters in that field!), and the E-620 is 837. Now that's more like the sort of ratio I would expect, not that from previous experience I expect any of those figures to bear anything close to reality!!
But given the E-620 has a larger pixel count than the E-3, would you not have expected the ratio to be the other way around Stephen?

StephenL
2nd September 2009, 01:44 PM
I was naively going on the relative sizes of the sensor - 10 million pixels versus 12. Or thereabouts. But of course if, as you say, the density of the sensor is different that would affect the amount of data which is actually captured. :confused:

But given the E-620 has a larger pixel count than the E-3, would you not have expected the ratio to be the other way around Stephen?

stevednp3
2nd September 2009, 07:27 PM
Strange fact i found out that when I got my e-30 it would hold more jpeg and raw than my 410 did on the same 2gb and thats 12.3mp vs 10mp - strange :confused:

Rod Souter
2nd September 2009, 08:24 PM
I recall reading that the E-3 compresses RAW files and the amount of compression varies with the nature of the picture and the quoted number is only an estimate. As files are added the number available can increase!

I of course may be talking complete b****cks.

Rod

Steambuff
2nd September 2009, 09:32 PM
Nope ... you are correct ......

I've just looked at my E3 RAW files, and they do vary in size (in my case) from about 9Mb to just under 12Mb each.

Dave

JohnGG
2nd September 2009, 09:42 PM
I recall reading that the E-3 compresses RAW files and the amount of compression varies with the nature of the picture and the quoted number is only an estimate. As files are added the number available can increase!

I of course may be talking complete b****cks.

Rod

No, I don't think you are :)

I've kept an eye on the counter of my E-3 when getting close to filling a card and I've noticed that the number doesn't always decrement when taking a shot. The compression ratio must vary as E-3 raw files vary in size (E-1 raws do not so I guess that camera doesn't compress them). Given the larger sensor of the E-620, I surmise that the newer camera has a more powerful compression algorithm. Either that or the E-3 is a "glass half empty" camera and takes a pessimistic view of how many shots will fit whereas the E-620 is a "glass half full" sort :)

Cheers,

JohnGG

Zuiko
2nd September 2009, 10:20 PM
Why can't digital life be simple for once? :confused:

Never had this issue with a roll of 36 - except that if you were careful how you loaded it you could sometimes squeeze an extra one on the end. :D

Nick Temple-Fry
2nd September 2009, 10:30 PM
On a blank 8Gb card my E-3 shows 472 available images, now that must mean Olympus reckon an E-3 raw file is just under 17mb. But on a recent nearly full card the range of sizes was between 8mb and 12mb and the card held 786 images.

Can't help but wonder if Olympus used the uncompressed size of an E-3 raw file (whatever that is) in writing the algolrithm, as even the suggested size for a raw file (11mb) would give over 700 images.

Now a number of review sites quote the raw compression as being by 65%, if that was to (rather than by) 65% and we assume the average 'intended' size was 11mb - then that also gives about 17mb.

Of course this may all well be rubbish, as it's a bit late at night to be doing sums.

Nick

Dick Bowman
3rd September 2009, 06:16 AM
As I understand it - the algorithm used by the E-3 is pessimistic, so you can be pretty sure that you can actually save more images than it predicts. Also the estimation gets more accurate as the card fills up. Actual file sizes depend on the complexity of each image. The E-1 does not compress - hence all files the same size.

snaarman
3rd September 2009, 07:27 AM
Why can't digital life be simple for once? :confused:

Never had this issue with a roll of 36 - except that if you were careful how you loaded it you could sometimes squeeze an extra one on the end. :D

In an attempt to squeeze more shots out of a Provia 36 years ago, I loaded it in the dark - then went out on an early morning photo search the next day and used the first possible shots on the film. I forgot that my old Nikon started on default 1/250th second until you had wound forwards twice. Net result was a sunrise and tree scene about 5 stops underexposed.

It actually turned out to be a spectacular shot :-)

We don't make that kind of mistake these days. Anyone accidentally loaded a monochrome CF card when they intended to shoot colour?

Pete

andym
3rd September 2009, 01:58 PM
As far as I'm aware all E series cameras since the E400 used compressed Raw.

That why the 10 megapixel E400 has very large Raw file sizes and why the E1's files are all 10412kb.