How does overflow work with dual cards? (Nikon D500)

L

LukeC

Suspended / Banned
Messages
282
Edit My Images
Yes
A bit of a strange question, but I googled and couldn't find the answer i'm looking for...
How does the overflow option work with dual cards? Specifically; does the camera write to the primary card until it's full, and then start writing images directly to the secondary card? Or does it always write to the primary card, and shunt pictures from primary to secondary in the mean time?
I'm asking because i'm looking at options for my D500, but XQD cards are much more expensive. I was considering a modest 32GB XQD to clear the buffer quickly, and I already have a larger SD card for overflow if I fill the 32GB. The problem is, the SD card isn't particularly fast (in D500 terms) so I don't want to fill the 32GB card and suddenly lose a massive amount of speed.
So, sorry if this is a confusing jumble of questions... does anyone have an answer please?
Many thanks,

Luke
 
My understanding is that it fills the card in Slot A then moves to Slot B.
From my experience with the D500, using a Sandisk Extreme Pro 95Mb/s SD card was more than enough for fast shooting and reasonable bursts ... if machine gunning then probably not but faster cards are available.
 
gramps said:
My understanding is that it fills the card in Slot A then moves to Slot B.
From my experience with the D500, using a Sandisk Extreme Pro 95Mb/s SD card was more than enough for fast shooting and reasonable bursts ... if machine gunning then probably not but faster cards are available.
Click to expand...
Thanks Gramps. I think my card may be exactly that, the Extreme Pro 95Mb/s. If I understand what i'm looking at, bearing in mind i've only had my hands on the camera half a day, then it gives me 29 shots before the buffer is full. I haven't tested how quickly it clears though, as i'm not that keen to fire off huge bursts at nothing just to test it!
 
gramps said:
My understanding is that it fills the card in Slot A then moves to Slot B.
From my experience with the D500, using a Sandisk Extreme Pro 95Mb/s SD card was more than enough for fast shooting and reasonable bursts ... if machine gunning then probably not but faster cards are available.
Click to expand...

Yep, the camera writes to whichever slot you have selected as Primary (usually the XQD) then starts writing to the Secondary slot when the Primary is full (in Overflow mode).

Regarding cards, it really depends on how long a burst rate you need for the type of subject you shoot. I'm using SanDisk Extreme Pro 300MB/s SD cards and I do get a buffer increase over the 92MB/s.

GC
 
Last edited:
170mb/s sd cards are literally pennies now. I would try one and see if it meets your needs and then go from there.

I was in a bit of an xqd quandary for my D850 as I don’t need the speed (at all) but did need the dual card slots for redundancy.
In the end I just bought 3 64gb sd cards and one 64 xqd card (second hand) to be used as an internal back up, I don’t even have an xqd reader. I simply use the sd cards and back up to xqd.
 
LukeC said:
Thanks Gramps. I think my card may be exactly that, the Extreme Pro 95Mb/s. If I understand what i'm looking at, bearing in mind i've only had my hands on the camera half a day, then it gives me 29 shots before the buffer is full. I haven't tested how quickly it clears though, as i'm not that keen to fire off huge bursts at nothing just to test it!
Click to expand...

I think that the greatest number of burst shots I fired off at any one time was 12 and I don't recall any delay just using the SD card, personally I have never needed to fire off more than that, and it has been very rare,
 
gcgraphs said:
Yep, the camera writes to whichever slot you have selected as Primary (usually the XQD) then starts writing to the Secondary slot when the Primary is full (in Overflow mode).

Regarding cards, it really depends on how longer burst rate you need for the type of subject you shoot. I'm using SanDisk Extreme Pro 300MB/s SD cards and I do get a buffer increase over the 92MB/s.

GC
Click to expand...
Thanks GC. I do mostly wildlife, and i'm sure 29 shots would cover most scenarios (near enough 3 seconds at 10fps CH) I can only think of a few times I would've gone past that, and then I could just let off briefly and clear some buffer space. I've noticed that E-Infinity have a 32GB XQD for £67, sold out currently, so i'll probably pick that up then consider my current SD good enough if I fill it.
 
gramps said:
I think that the greatest number of burst shots I fired off at any one time was 12 and I don't recall any delay just using the SD card, personally I have never needed to fire off more than that, and it has been very rare,
Click to expand...

Like I said, it depends how and what you shoot:)

GC
 
Brazo said:
170mb/s sd cards are literally pennies now. I would try one and see if it meets your needs and then go from there.
Click to expand...
Just to check i'm not being thick, is it the read or the write speed that's important in this scenario? I've seen plenty of cards with high read speeds, but still only 95mb/s write speeds like mine.
 
LukeC said:
Just to check i'm not being thick, is it the read or the write speed that's important in this scenario? I've seen plenty of cards with high read speeds, but still only 95mb/s write speeds like mine.
Click to expand...

Write speed is the important factor. Also the minimum average write speed is probably more important that is rated V30, V60, V90 etc.

This might help.

https://www.cameramemoryspeed.com/nikon-d500/sd-and-xqd-card-speed-test/


Cards never work at there advertised speeds.
 
On a dual card Canon you can configure it in different ways - fill one first then the other, as a duplicate of the first, or shoot different formats to different cards. Canon's don't shunt images about from one to the other unless you use the copy image function.

Both my Canon bodies have twin card slots, but one is a CFast + CF, the other an SD + CF. I use mine most of the time to shoot a full res image to the CF, and then a smaller JPG to the other. I start releasing images from the smaller files during the course of a motor racing weekend, leave the full size images until after the event has finished. Quicker to download, quicker to edit, quicker to upload to web via mobile internet whilst on a laptop with finite battery capacity.
 
andrewc said:
you can configure it in different ways - fill one first then the other, as a duplicate of the first, or shoot different formats to different cards.
Click to expand...

Same options on Nikon too(y)

GC
 
LukeC said:
Just to check i'm not being thick, is it the read or the write speed that's important in this scenario? I've seen plenty of cards with high read speeds, but still only 95mb/s write speeds like mine.
Click to expand...
Sorry Luke it’s me not you! Having just checked it would appear I’ve been taken in by the headline figure! Yes the write speeds are around 90mb/s.
 
No worries! I think I've decided to hold off on a new card, unless I spit a mega deal on an XQD. As several have mentioned, there aren't many situations that need more than 29 frames continuously! Specially not in lockdown...
Brazo said:
Sorry Luke it’s me not you! Having just checked it would appear I’ve been taken in by the headline figure! Yes the write speeds are around 90mb/s.
Click to expand...
 
Re: Dual cards in the Canon bodies

My 5D3 has CF and SD cards
I never used the SD slot because it was reported by reviewers who did speed testing that whatever speed CF card used, if there was an SD of slower speed (all were at the time of writing so to speak) in use it would set the lower write speed for both the CF and SD slots!!!! Not a good thing for burst shooters but possibly fine for studio and non-wildlife or aviation togs ???
 
You must log in or register to reply here.
Back
Top