Does using a second SD card slow up a Z8

[Len Shepherd]

Quote from a Nikon interview at digital camera world
"When recording RAW and JPEG at the same time for high-speed continuous shooting, the performance may be degraded if the SD card is a very low-grade one, but there is no significant performance degradation if the customer is using a UHS-II type SD card. So as long as Nikon-recommended cards are used, there will be no significant reduction in performance."

I do not have a Z8 yet - so I cannot test.
"No significant reduction "is not quantified.
jpg are smaller files then NEF.
Perhaps any slight reduction is much smaller than many presume.

 

[John Navitsky]

you should be able to compute it. the “v” rating of the sd card will indicate its sustained write speed, divide by average jpg size and you’ll get how many frames per second it should be able to sustain

 

[Robert S]

Why would it be beneficial to record RAW and JPEG at the same time?

 

[John Navitsky]

Why would it be beneficial to record RAW and JPEG at the same time?

people do this for a variety of reasons:

1) they want to deliver a small, publication ready image to an outlet for immediate publication, but also have a RAW image for subsequent processing for maximum quality.

2) they simply want a "just in case" backup but they don't want to be slowed down by the overhead of writing a second raw file (esp. with an sd card) so they pick the smaller jpg. they may prefer having a raw backup, but they consider the jpg "better than nothing"

 

[pe1125]

people do this for a variety of reasons:

1) they want to deliver a small, publication ready image to an outlet for immediate publication, but also have a RAW image for subsequent processing for maximum quality.

2) they simply want a "just in case" backup but they don't want to be slowed down by the overhead of writing a second raw file (esp. with an sd card) so they pick the smaller jpg. they may prefer having a raw backup, but they consider the jpg "better than nothing"

Or in my case, 95% of my shots are good enough as jpegs (or to put it another way, not worth having a RAW version), and for the 5% that I think are worth the effort I have the RAW file available. When you shoot 500-100 shots in a morning and have only a few "keepers" in the sense of composition/subject/action as well as focus & exposure I find it easier to cull jpegs rather than transfer and cull all those RAW files. Works for me, YMMV.
Peter

 

[Robert S]

people do this for a variety of reasons:

1) they want to deliver a small, publication ready image to an outlet for immediate publication, but also have a RAW image for subsequent processing for maximum quality.

2) they simply want a "just in case" backup but they don't want to be slowed down by the overhead of writing a second raw file (esp. with an sd card) so they pick the smaller jpg. they may prefer having a raw backup, but they consider the jpg "better than nothing"

Seems reasonable.

 

[Robert S]

Or in my case, 95% of my shots are good enough as jpegs (or to put it another way, not worth having a RAW version), and for the 5% that I think are worth the effort I have the RAW file available. When you shoot 500-100 shots in a morning and have only a few "keepers" in the sense of composition/subject/action as well as focus & exposure I find it easier to cull jpegs rather than transfer and cull all those RAW files. Works for me, YMMV.
Peter

Again seems reasonable.

 

[agrumpyoldsod]

Quote from a Nikon interview at digital camera world
"When recording RAW and JPEG at the same time for high-speed continuous shooting, the performance may be degraded if the SD card is a very low-grade one, but there is no significant performance degradation if the customer is using a UHS-II type SD card. So as long as Nikon-recommended cards are used, there will be no significant reduction in performance."

I do not have a Z8 yet - so I cannot test.
"No significant reduction "is not quantified.
jpg are smaller files then NEF.
Perhaps any slight reduction is much smaller than many presume.

Well obviously it all depends. This really only counts when shooting Continuous HIGH (20fps or close) and long bursts. See other threads for details of how the buffer works and so on

I only shoot Lossless RAW and simply will not shoot action writing to both cards. The fastest UHS-II SD cards are rated V90 and the fastest I found is 1/5th the speed of my 650GB Delkin Black CF Express Type B card.

My answer to you is:
YES definitely if using Backup
Yes possibly if saving Raw to CFE and HEIF/JPG to a slow SD
NO if the SD is used for overflow.

 

[John Navitsky]

v90 should do 250MB/s, large fine jpg is about 24.1MB, so you may be able to sustain about 10fps when backing up to a v90.

caveat, it is possible there is a limit to the over-all bandwidth limit that encompasses BOTH cards, and if so, the limit may be even lower

 

[EricBowles]

Quote from a Nikon interview at digital camera world
"When recording RAW and JPEG at the same time for high-speed continuous shooting, the performance may be degraded if the SD card is a very low-grade one, but there is no significant performance degradation if the customer is using a UHS-II type SD card. So as long as Nikon-recommended cards are used, there will be no significant reduction in performance."

I do not have a Z8 yet - so I cannot test.
"No significant reduction "is not quantified.
jpg are smaller files then NEF.
Perhaps any slight reduction is much smaller than many presume.

This makes sense. When you add a JPEG, you have more data. When it is being written to a second, slower card, depending on the size and quality of the JPEG being created, the additional data may or may not be material. I've seen SD cards that only had a write speed of 37 MB/s - and shooting at 15-20 fps even with a medium quality JPEG that's going to take time to write.

If you are writing RAW + JPEG, the fastest approach is to write both files to the CFExpress card and then separate them later if needed. You can easily download small basic JPEG files only using Windows Explorer or the equivalent.

 

[JoelKlein]

Or select all Jpegs in camera and copy to the SD when you have an extra moment