Nikon D300S Performance

Generally above average speed for a compact-body pro SLR.

Startup time is about average for a semi-pro SLR, but shutdown is slightly slow (probably due to sensor cleaning). Buffer clearing times depend on the image size and quality, burst length and how fast the card can be written to, but are generally pretty fast.

The Nikon D300S supports UDMA data transfers, so can take advantage of very fast cards like the SanDisk Extreme Pro series. Buffer clearing times aren't directly proportional to differences in card speed, but there is still a noticeable improvement. In the above examples, the SanDisk Extreme Pro card is rated at twice the data transfer speed of the Extreme IV model. The clearing time for uncompressed 14-bit RAW files improved from 14.9 to 8.2 seconds, but the buffer depth also increased from 19 to 25 shots, a not-insignificant improvement.

Mode switching is very fast, difficult to measure accurately.

The shutter lag numbers above measure time from shutter button press to image capture, with the lens already set to the correct focal distance. This largely removes the issue of differences in lens focusing speed, and measures how fast the camera can measure and act on focus information. In this metric, the Nikon D300S is a bit slower than average for a compact-body pro SLR. The D300S required 0.225 second for full AF when using Single-point (center) AF mode (our default full AF lag test), almost exactly the same as the time we measured for the D300. The D300S required 0.37 second when using the 51-point Auto-area AF mode, a bit faster than the D300's 0.42 second. When prefocused, shutter lag was only 0.053 second, just slightly faster than the D300's 0.057 second lag. Continuous and Manual focus lag times were 0.155 second and 0.150 second respectively, though, both slower than the D300's 0.056s and 0.054s for those modes.

As expected, the Nikon D300's two Live View modes add considerable delay. The "Hand-Held" mode which uses the same "mirror-down" phase-difference AF method employed when using the optical viewfinder has a full AF shutter lag of 0.47 second in Single-point AF mode, roughly double the optical viewfinder lag, but very similar to this mode on the D300, and quite a bit faster than "quick mode" (phase-detect) AF on competing Canon models in Live View mode. The "Tripod" Live View mode is much slower at 2.5 seconds, but focusing must be triggered using the AF-On button, so there's a little of the photographer's reaction time included in that figure, in pressing the shutter button once he/she hears the focus-confirmation beep. When prefocused, "Hand-Held" mode shutter lag is a very fast 53 milliseconds. (Although it deserves noting that there's little point to shooting prefocused in hand-held mode, as the viewfinder is blacked out as long as the shutter button is held down in readiness. Releasing the shutter button restores the viewfinder display, but you'll then incur the full-AF shutter lag when you go to capture the shot.) In "Tripod" mode, prefocused shooting is quite slow at 0.42 second, probably because the camera must drop and re-open the mirror to take the shot.

To minimize the effect of different lens' focusing speed, we test AF-active shutter lag with the lens already set to the correct focal distance. We also use the same Sigma 70mm f/2.8 macro with every camera (on all platforms except Four Thirds/Micro Four Thirds and Nikon consumer models lacking an in-body focus motor), to further reduce variation, and because our tests showed that focus-determination time with this lens was close to the fastest, across multiple camera bodies from different manufacturers. Being an older design with a non-ultrasonic motor, it wouldn't be the fastest at slewing from one focus setting to another, but that's exactly the reason we measure focus determination speed, which is primarily a function of the camera body, vs focus adjustment speed, which is primarily a function of the lens.

Shot-to-shot cycle times were a little slower than the D300, at 0.48 second for Large/Fine JPEGs or 12-bit lossless compressed RAWs, and 0.47 second for 12-bit lossless compressed RAW + Large/Fine JPEGs, all with a single AF point selected, and the camera set to focus priority. (The D300 managed 0.39 seconds for all three modes.) When set to release priority, times improved to 0.21 - 0.22 second, while in manual focus, the minimum cycle time decreased to 0.19 second. Continuous mode for Large/Fine JPEGs and 12-bit RAWs was very fast though, ranging from 7 to 7.1 frames-per-second, depending on the mode. This is about one frame-per-second faster than the D300 (without the optional battery grip). Like the D300, though, the Nikon D300S slowed significantly in 14-bit RAW mode, dropping to about 2.7 frames per second. Buffer depths were quite good. Some were better than the D300 (14-bit RAW), some worse (LF JPEG), and some about the same (12-bit RAW). The flash takes 1.7 seconds to recharge after a full-power shot, which is pretty fast.

Just prior to publishing this review, we received samples of the SanDisk Extreme Pro Compact Flash card, rated for 90 MB/sec read and write speeds using the UDMA 6 protocol (twice the speed of the Extreme IV model we'd previously been using to measure buffer clearing times). We ran a couple of tests recording uncompressed RAW files, to see what effect the faster card had on clearing times, and were impressed that it improved clearing times by 35-57%. The few seconds difference won't make a lot of difference to many users of the D300S, but anyone concerned about maximum image throughput will definitely find UDMA 6 cards worth the extra cost.

The Nikon D300S has both CF and SD card slots: If you have two cards loaded simultaneously, you can configure them in a variety of different ways, using the SD card as a backup, as an overflow, or just to receive JPEG images. We didn't test all the permutations and combinations of this configuration, but did run a few tests to see how buffer clearing speed varied between the two card types. Here's a little table, comparing results with two different CF cards with those from two different SD cards:

As you can see, CF cards are pretty dramatically faster than SD cards, and new UDMA 6 cards like the SanDisk Extreme Pro line are quite a bit quicker than even very fast cards of the immediately prior generation. On the SD side, we tried both a SanDisk Class 6 card, and a card rated for Class 10 performance from the relatively new vendor Photofast. The Class 10 PhotoFast card came in quite a bit slower than the Class 6 SanDisk Extreme III with this camera. The PhotoFast SD might well be a Class 10 card, but it's important to note that the "Class" rating system refers to minimum guaranteed transfer rate, not peak throughputs. As such, it has more relevance to video recording than flushing still images from a memory buffer. (In separate tests of PhotoFast high-speed CF cards, we've been pleased to see them coming close to the performance of high-end cards from SanDisk and Lexar, yet selling at considerably lower prices: We'll try to do a memory-card roundup at some point, to shed a little light on cost vs performance figures there.)

Connected to a computer or printer with USB 2.0, downloads are quite speedy.

Bottom line, the Nikon D300S is a very responsive camera overall, but autofocus speeds are slightly slow for a compact-body pro-level SLR. While continuous mode speeds when shooting JPEGs or 12-bit RAWs were very fast, switching to 14-bit RAW slows cycle times quite a bit, so you'll need to avoid 14-bit mode for fast action shots.

Battery
Excellent battery life for a lithium-ion design.

The Nikon D300S uses a custom rechargeable lithium-ion battery for power, and ships with a charger. Battery life is excellent with the optical viewfinder, but if you plan to use Live View or shoot movies much, you'll definitely want to have a spare battery to bring along.

The table above shows the number of shots the camera is capable of (on either a fresh set of disposable batteries or a fully-charged rechargeable battery as appropriate), based on CIPA battery-life and/or manufacturer standard test conditions.

(Interested readers can find an English translation of the CIPA DC-002 standards document here. (180K PDF document))

Storage
The Nikon Nikon D300S accepts CompactFlash and SD/SDHC memory cards. No card is included with the camera.

The numbers in the table above reflect using the Optimal Quality setting for the D300S' JPEG compression: Using the Size Priority option will increase the number of images that can be stored, at some cost in image quality. We strongly recommend buying a large capacity CompactFlash or SDHC card. You should probably consider at least a 2GB card, if not a 4GB or 8GB one, to give yourself extra space for extended outings, especially if you plan on doing a lot of RAW or HD movie shooting. (Check the shopping link above, cards are cheap these days, so there's no reason to skimp -- But do consider faster cards for this camera, to reduce buffer clearing times.)