Published: May 30, 2017
The Panasonic GH5 is an advanced, feature-filled interchangeable lens mirrorless digital camera. Incorporating a 20.3MP sensor with in-body stabilization the camera is suited to both still photography and video. It can record 4K video at 60 fps and HD video up to 180 fps. For still photographers it offers up to 12fps continuous shooting at full resolution. The GH5 has dual SD card slots and both slots support the UHS-II interface. Standard SD and UHS-I cards can be used but UHS-II cards offer the best performance.
A total of 119 memory cards were tested in the GH5. The cards tested include both UHS-I and UHS-II. The results are presented in two tables. The first shows the average write speed during continuous shooting of RAW images and the second table shows the number of shots during continuous shooting for 30 seconds using in three images modes (RAW+JPEG, RAW and JPEG modes). An analysis follows with more details observed during the tests. The fastest SD cards for the Panasonic GH5 are provided based on the test results for this camera.
The test is conducted with the GH5 mounted on a tripod. The shutter is operated using a remote release timer. The camera settings are chosen to reduce all internal processing of the images and all manual settings are used to assure consistency. An adapted manual lens is attached to the camera and focus and aperture are set on the lens. The test image is of a detailed scene with controlled lighting that remains constant throughout the test. Write speed is calculated during the buffer-full write condition during extended continuous shooting. The amount of data written to the card in bytes divided by the write time in seconds gives the write speed in MB/s (1 MB = 1,048,576 bytes). Results for write speed are for RAW images because they provide a higher write speed than RAW+JPEG and JPEG modes.
The second table shows a comparison of the number of shots that can be taken in 30 seconds. This time does not include the buffer clearing and is limited by the write speed of the cards. The release mode is continuous high and uses the maximum frame rate provided by the GH5. The image modes tested are RAW+JPEG, RAW and JPEG. The JPEG setting is large, quality priority. The test scene produced 23.1 MB RAW files and 7.9 MB JPEG files.
The Panasonic GH5 offers the best performance when using UHS-II cards. Write speeds averaged up to 91.9MB/s using UHS-II cards. UHS-I cards only reached up to 40MB/s average during continuous shooting. The GH5 does not support the faster UHS-I SDR104 mode, so even UHS-II cards with moderate write speeds such as the Lexar 1000x and Sony M Series offer better performance than the fastest UHS-I cards in the GH5.
The GH5 has a large buffer and captured between 64 to 72 shots at full frame rate in RAW mode. Cards with higher write speed allow more shots because they clear the buffer faster during shooting. Once the buffer reaches capacity the camera prevents further shots until there is enough room in the buffer to continue shooting. With the camera buffer full, shooting was limited to between 0.6 fps using the slowest card and 4fps with the fastest card. These numbers will change with a different image subjects and camera settings. The detailed test scene in this test produced relatively large files. When shooting less detailed subjects the number of shots at full frame rate and frame rate with the buffer full will increase.
When shooting RAW+JPEG the GH5 could shoot between 63 shots at full frame rate with slow cards up to 67 shots with faster cards. The difference between cards was most apparent with the buffer full, where the slowest card only shot 4 additional shots in 24 seconds, or under 0.2 fps. Faster cards shot up to 52 shots with the buffer full during the same time, just over 4 fps.
Fast memory cards allow practically unlimited continuous shooting at full frame rate in JPG mode. The detailed test scene resulted in 242 shots at full frame rate with the fastest card and only slowed slightly for the remainder. A less detailed image could allow unlimited shooting. The slowest card tested captured 107 shots at full frame rate before slowing to 1.4 fps in JPEG mode.
In general, 64GB and larger SDXC cards performed slightly faster than 32GB SDHC versions of the same card in the GH5.
Some UHS-II cards operated in UHS-I mode in the GH5. Older Lexar Professional 1000x and 2000x UHS-II cards with production dates of 12/2015 or earlier were apparently operating in UHS-I mode. This is most likely due to a controller issue in the GH5 and these cards are probably forced into UHS-I mode by the firmware in the GH5. The affected cards function normally in every other camera and card reader test performed to date. Since the GH5 also doesn't support SDR104 mode in UHS-I, these normally fast UHS-II cards were operating well below their speed potential in the camera. Newer production Lexar 2000x and 1000x UHS-II cards performed as expected. Newer cards are noted in the charts above with a revision in the card name (eg. Rev E). This revision code is printed above the bar code on the product packaging.
The GH5 has dual SD card slots and supports UHS-II cards in both slots. There are three ways to use the slots: use one after the other is full (overflow), write the same images to both cards (backup) or write different image formats separately to each card. Performance in overflow mode is the same as when shooting with only one card in the camera.
Writing the same images to both cards (backup) reduces overall performance. With Sony G-Series UHS-II cards in both slots, 103 RAW+JPEG were captured in 30 seconds, versus 119 when writing to only one card. In RAW mode 121 images were captured, which is less than the 163 that just one card alone provided. The write speed averaged 51.4 MB/s writing RAW to both cards compared with the 91.9MB/s average when writing to one card. When shooting JPEG only, 211 images were captured to both cards in 30 seconds, versus 314 for one card. When using cards with diffrent write speeds in backup mode, the speed will be reduced by the speed of the slower card.
Writing RAW to one card and JPEG to the second card provided nearly the same performance as writing both image types to one card, assuming a fast card is used in both slots. Compare the charts below for examples using different card and shooting combinations. The chart below shows the number of shots captured in 30 seconds of continuous shooting. The time does not include buffer clearing.
Mode: Overflow | RAW + JPEG | RAW | JPEG |
---|---|---|---|
Sony SF-G UHS-II 64GB | 119 | 163 | 314 |
Sony SF-G UHS-II 128GB | 119 | 163 | 303 |
SanDisk Extreme Pro UHS-I V30 256GB | 95 | 111 | 214 |
SanDisk Extreme UHS-I V30 256GB | 95 | 111 | 210 |
Mode: Backup Card 1 & Card 2 | RAW + JPEG | RAW | JPEG |
Sony SF-G UHS-II 64GB (Card 1) Sony SF-G UHS-II 128GB (Card 2) | 103 | 121 | 211 |
SanDisk Extreme Pro UHS-I V30 256GB (Card 1) SanDisk Extreme UHS-I V30 256GB (Card 2) | 79 | 87 | 155 | Mode: RAW Card 1 / JPEG Card 2 | RAW & JPEG |
Sony SF-G UHS-II 64GB (RAW) Sony SF-G UHS-II 128GB 64GB (JPEG) | 121 | ||
Sony SF-G UHS-II 128GB (RAW) Sony M Series UHS-II 128GB (JPEG) | 117 | ||
Sony SF-G UHS-II 64GB (RAW) SanDisk Ultra 80MB/s 64GB (JPEG) | 93 |
The fastest card for the GH5 is the Sony SF-G UHS-II 64GB card. The 128GB version of the G Series card performed nearly as fast. Next fastest were Lexar 2000x UHS-II cards, with the Lexar 2000x UHS-II 64GB Rev E SDXC Card operating nearly as fast as the Sony G Series cards. Several other UHS-II trail just behind, with Hoodman Steel 2000x UHS-II, Transcend Ultimate UHS-II and SanDisk Extreme Pro 300MB/s UHS-II cards in various capacities among the top 12 fastest cards for average write speed in the GH5.
The best value SD cards for the GH5 are Sony M Series cards. The M Series UHS-II cards have a lower write speed compared to the G Series, but cost significantly less. Since the GH5 is not able to take advantage of the full write speed of the fastest UHS-II cards, the M Series perform nearly as well as the G Series in the camera. Additionally, the M Series cards offer a very high 260MB/s read speed (with benchmarks reaching above 270MB/s read speed). The GH5 does not support UHS-I SDR104 mode, which limits UHS-I performance. The GH5 requires UHS-II cards to enable higher write speeds.
The fastest UHS-I card in the camera was the SanDisk Extreme Pro 95MB/s U3 V30 256GB and was followed closely by several other size SanDisk Extreme Pro and Extreme Plus cards. With UHS-I cards the highest average write speed measured was 40.0 MB/s.