Storage discrepancy between M10P and M10M

[AceVentura1986]

Advertisement (gone after registration)

Hello, all. I own an M10M and an M10P. The M10M is loaded with a 256gig card while the M10P is loaded with a 128gig card, 50% less capacity. However, I would think that the two cards would show the same capacity given that the M10P’s files are also 50% the size of the M10M’s files. However, this is not the case. The M10P’’s card shows roughly 3,000 photo capacity while the M10M’s card shows roughly 6,000 photo capacity. I actually don’t care if it’s 3,000 or 6,000 because I’ll never even come close to filling the lower capacity. Still, it does seem a conundrum. If the card is 1/2 size but the files are also 1/2 size, I would think the total storage should be approximately equal. 

Any thoughts on this? 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[dugby]

Does changing the image file settings alter the numbers ?

eg DNG only, JPEG only, etc

[dynaerik]

You are comparing black & white with color pictures. Black & white pictures need less bytes. I think that’s why there is the difference. 

[adan]

1 hour ago, dynaerik said:

You are comparing black & white with color pictures. Black & white pictures need less bytes. I think that’s why there is the difference. 

Not quite that simple.

M10 Monochrom as a 40Mp sensor, and file sizes of ~52-60 megabytes. M10-P has a 24Mp sensor and file sizes of ~25-32M pixels. (from my own file archives)

However, note the wide variation in file sizes for either camera, which can be due to the following.

A .DNG file includes a place-holder preview .jpg image in the file (otherwise there would be nothing to see on the camera screen).

That placeholder jpeg can vary in size depending on how well it can be compressed. That depends on how much of the image is sharp and focused - blurry backgrounds can be .jpg-compressed a lot, while areas of continuous sharp detail cannot. And "noise speckles" count as "sharp detail" as well, so the ISO in use will affect compressability and capacity also.

Key Point for AceVentura1986: because no two .DNG files will actually be the same size, even from the same camera, what the camera tells you is only an approximate prediction of remaining capacity, for an "average" picture.

You'd amazed at how often, as I fill up a card, the "remaining space" the camera reports after each shot does not decrease linearly. Sometimes, I see "21 shots remaining," and after taking 20 shots, it reads "13 shots remaining."

It is also true that the M10M - being newer and more advanced and with quite different firmware - may simply use (or expect to use) the space on the card more efficiently, or have other differences, or make other assumptions about "average" file sizes.

And for certain the metadata needs per image will be different - e.g. the Monochrom does not have to store "white balance as shot" metadata. 😆

Finally, note that the stated capacity of the card is not the full capacity of the card (Your "128gb" card only has 118gb actually free, even whe there are no pictures yet). The rest of the space, in either card, is for "housekeeping" - image index, assigning slots in the silicon memory, etc.

I guess the short version for all that would be "comparing apples to coconuts."

 

Edited July 7, 2024 by adan

[mujk]

What happens after one or a few pictures have been taken with both cameras? Will the indicated capacities still have approx. the same ratio?

[AceVentura1986]

20 hours ago, mujk said:

What happens after one or a few pictures have been taken with both cameras? Will the indicated capacities still have approx. the same ratio?

Good question. I’ll check and post result. 

[AceVentura1986]

Advertisement (gone after registration)

On 7/10/2024 at 7:26 AM, AceVentura1986 said:

Good question. I’ll check and post result. 

Sorry for the delay, but I've been pretty bogged down recently. To restate the issue, my M10M is loaded with a 256gig card while the M10P is loaded with a 128 gig card, 50% less capacity. However, I would think that the two cards would show the same capacity given that the M10P’s files are also 50% the size of the M10M’s files. However, this is not the case. The M10P’’s card shows roughly 3,000 photo capacity while the M10M’s card shows roughly 6,000 photo capacity." This is the case even though the M10M files are approximately 50MB and the M10P's are approximately 25MB.

@mujk then asked what happens if I shoot off a series of photos. Excellent question. I set both cameras to ISO 200, 1/60 shutter, formatted both cards and photographed the same closet door 25 times on each camera. I snapped photos with my phone of the rear screens after the formatting and then immediately after shooting 25 photos. 

• M10M after formatting but before 25 photos: 6102
• M10M calculated theoretical photos remaining: 6077
• M10M actual figure after 25 photos: 6079, or 99.62% remaining
• M10P after formatting but before 25 photos: 3045
• M10P calculated theoretical photos remaining: 3020
• M10P actual figure after 25 photos: 3031, or 99.54% remaining

So, obviously, the ratios are slightly different but still within the expected range. At present, the discrepancy between the two memory cards still remains a mystery, especially given that the files are roughly 50MB vs. 25MB. I've attached the photos below for reference.

 

 

 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[jaapv]

Nominal storage space is not actual storage space. When the card is initially formatted after production, bad sectors on the card will be blocked. This varies per card. 

[AceVentura1986]

21 minutes ago, jaapv said:

Nominal storage space is not actual storage space. When the card is initially formatted after production, bad sectors on the card will be blocked. This varies per card. 

Yes, I'm sure that's correct but I still doubt it accounts for such a large disparity. Perhaps, but IMHO the disparity seems too large.

[Al Brown]

It is like comparing gas mileage of two different car models of the same make with different fuel tank sizes and different MPG under different driving conditions, citing manufacturer specs. Impossible.

[pop]

It appears that one camera assumes the average (or max) image size to be 38.83MB while the other thinks it's 38,75MB, i.o.W. both assume the same size per image. They didn't change the constant from one camera to the other one, I'd think.