Sony Cyber-shot DSC-F717Sony updates their already-impressive five megapixel F707, with improved user controls, better color, amazing white balance performance, and an external flash hot shoe!<<Optics :(Previous) | (Next): Shutter Lag & Cycle Time Tests>> Page 6:Exposure & FlashReview First Posted: 9/2/2002 |
Exposure
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In the Scene exposure mode, you have the option of shooting in Twilight, Twilight Portrait, Landscape, or Portrait preset modes. Twilight mode sets up the camera for shooting night scenes, using a slower shutter speed to capture more ambient light. (Sony's philosophy is to not offer shutter speeds slower than those that can be handheld reasonably well (1/30 second or faster) in normal exposure modes, so users don't end up with blurry photos because they didn't realize the camera was using a slower shutter speed.) Use Twilight mode in any situation where the lighting is too dim to give a good exposure in normal exposure mode, but be aware that the camera will be using slower shutter speeds. - Mount it on a tripod or otherwise provide stable support. Twilight Portrait operates under the same guidelines, but automatically uses the Slow Sync flash setting, so foreground subjects (people, for instance) are properly illuminated. Landscape mode simply uses a smaller lens aperture to increase the depth of field, keeping the foreground and background in focus. Landscape mode typically uses slower shutter speeds, so a tripod is recommended in all but bright lighting. Portrait mode works in the opposite manner, using a larger aperture to decrease the depth of field. This produces a sharply focused subject in front of a slightly blurred background.
I've quibbled with Sony about their Twilight-mode philosophy, personally preferring a camera that offers a full range of exposure times in its normal exposure mode, but that simply warns me (jiggling hand symbol, etc) when the shutter speeds get slower than some given level. I understand the reasoning behind Sony's normal/twilight dichotomy though, and have to admit that it makes sense. What I really haven't agreed with though, is Sony's recent tendency to automatically add about a -2EV (negative) exposure compensation to twilight mode exposures with most of their line of consumer cameras. The reason for this was most likely to preserve color in brightly-lit objects in night scenes, preventing them from blowing out to pure white. That's well and good, but since you had to use Twilight mode for any dimly lit subject, I found myself very frequently having to dial in as much positive exposure compensation as the camera would allow. I'm very happy to report that the F717 doesn't seem to exhibit this behavior at all. Shots I took in twilight mode came out properly exposed without any heroic exposure compensation on my part.
The F717 employs a Multi-Pattern metering system as its default, dividing the scene into several small sections and taking exposure readings for each section. The readings are then evaluated (not necessarily averaged) to determine the best overall exposure. Center-Weighted and Spot metering options are also available, accessed by pressing the Metering button on the lens barrel. You can increase or decrease the exposure with the F717's Exposure Compensation adjustment, which ranges from -2 to +2 exposure values (EV) in one-third-step increments and which is adjusted by pressing the Exposure Compensation button on the top panel and turning the Command dial. Final determination will have to await my testing of a production model, but the F717's exposure metering system seemed to be quite accurate.
In addition to the F717's NightShot and NightFraming low-light features (discussed in detail in the Viewfinder section earlier), the camera also offers an impressive Noise Reduction system. Activated automatically with shutter speeds of 2.5 seconds and longer, Noise Reduction does an outstanding job of reducing the image noise associated with long exposure times. Judging by the camera's operation, it looks like the F717 is shooting a "dark" frame after each exposure when the noise reduction mode is active, and then subtracting the noise in that dark frame from the captured image. It's obvious that the camera is doing something like this, because it takes roughly twice as long for it to complete a long exposure than the exposure time of the shot itself. The F717 seems to go beyond basic dark-frame subtraction though, in that I saw none of the "dead" pixels you'd normally find in a camera's images using this technique. - With dark frame subtraction, any hot pixel that saturated and went all the way to white ends up black in the final image, since it was pure white in both the actual photo and the dark frame itself. (By way of explanation, "white" means a value of 255. If the hot pixel was white in both the image and dark-noise reference frame, when the subtraction is done, 255-255=0, or black.) The F707 was a superlative low-light performer, and the F717 looks to be every bit as good. This camera can turn out beautiful, full-color images in conditions that will have you reaching for a flashlight to find your way around. (I mean that literally - The test model of the F717 turned out bright, colorful photos under conditions so dark I literally had a hard time seeing well enough to walk around.) Even at ISO 800, low light shots showed surprisingly little noise. (Quite a bit of noise at ISO 800, mind you, but a lot less than I was expecting.) I'll test this capability in greater depth once I receive a production model of the camera.
One suggestion for the Sony engineers, for the next generation of this camera: The 717 is so phenomenally "clean" on very long exposures, why not push the envelope even more, and give us 60 or even 120 second exposure times? (A "bulb" mode would be nice, but that would also require a remote trigger of some sort, to avoid camera shake from holding down the shutter button. - How about a remote trigger option for the F717's successor as well?)
An AE Lock button on the side of the lens lets you lock the exposure reading without also locking the focus. (As happens when you half-press the shutter button.) AE Lock works well with Spot and Center-Weighted metering, as you can base the exposure on a particular area of the subject without also having to lock the focus on that area as well. Simply aim the center of the viewfinder at the portion of the subject you want properly exposed and press the AE Lock button. The exposure will be locked until the Shutter button is fully depressed or until the AE Lock button is pressed again.
ISO can be adjusted to 100, 200, 400, or 800 sensitivity equivalents, or set on Auto. The F717's White Balance adjustment offers six settings: One-Push (manual), Auto, Daylight, Cloudy, Fluorescent, and Incandescent. The One-Push reading is set by placing a white card in front of the lens and pushing the One-Push button on the side of the lens barrel. (This is another advance over the F707, which only offered Auto, Daylight, Incandescent, or One-Push white balance options.)
As I mentioned earlier, the F717's automatic white balance performance is really quite remarkable. The camera didn't seem to care too much whether a room was lit by daylight, fluorescent, incandescent, or a combination of all three light sources. I could just point the camera, snap the shutter, and the 717 gave me back nice looking photos with just enough of the original color cast to remind me what the subject actually looked like. Poor handling of the incandescent lighting that's almost universal in US homes has been a major bugaboo of digicams until now. (Although some individual cameras did fairly well with it in the past, and the entire Kodak EasyShare line deserves favorable mention in this regard.) The F717 seems to set a new standard in this area, a very welcome occurrence. - Hopefully the other digicam manufacturers will take a page from Sony's book, and come up with similar white balance systems for their cameras in the near future.
The 10-second Self-Timer mode is activated by pressing the Down arrow button on the Four Way Arrow pad. Once in Self-Timer mode, a full press of the Shutter button kicks off the timer, which counts down 10 seconds before firing the shutter. The camera beeps and flashes an LED (on the top of the camera, between the microphone and speaker grilles) to mark the countdown interval. (Here's another suggestion for the Sony engineers: How about an option for the self-timer that would permit shorter delays? I've often found it handy to have a 2 or 3-second self-timer delay available when I'm using a digicam on a tripod when snapping a low light shot or a tricky macro setup. - The brief delay between pressing the shutter button and the shutter actually firing helps insure that the jiggle from pressing the shutter button doesn't cause any blurring of the final image.)
The F717 also offers a versatile Picture Effects menu, a standard feature on Sony digicams. The menu offers three creative options: Negative Art, Sepia, and Solarize. Negative Art reverses the color and brightness of the image. Sepia changes the image into brown, monochromatic tones. The Solarize option is really more of a level-slicing function, dividing the image into areas of fairly "flat" color. (Not really a "solarization" effect as old-line film types would understand the term.) These effects are "live" in Record mode, so you get a preview of the effect on the LCD monitor before you record the image. The F717 also offers a Sharpness function, which adjusts the overall image sharpness from -2 to +2 in arbitrary units.
After recording an image, the Quick Review function provides instant playback of the picture. Pressing the Left arrow button also activates the Quick Review mode, giving you the option of deleting the most recently recorded image.
Flash
The pop-up flash on the F717 features true TTL (Through The Lens) metering, for more accurate flash exposures. (This is surprisingly rare in the current digicam market. Many cameras from "camera" companies that you would think surely would have TTL metering do not.) The flash operates in Auto (no icon), Forced, and Suppressed modes, with a Red-Eye Reduction mode that can be enabled through the Setup menu. Auto mode lets the camera decide when to fire the flash, based on existing lighting conditions. Forced means that the flash always fires, regardless of light, and Suppressed simply means that the flash never fires. Red-Eye Reduction mode tells the camera to fire a small pre-flash before firing the full flash to reduce the effect of red-eye. Once enabled through the Setup menu, the Red-Eye Reduction flash fires with both Auto and Forced modes. Flash intensity can be manually controlled via the Record menu with choices of High, Normal, and Low. There is no flash release mechanism, as the camera pops open the flash on its own, once the Shutter button is halfway pressed (in all flash modes except Suppressed).
Sony estimates the F717's internal flash to be effective from 1.6 to 16.4 feet (0.5 to 5 meters) in the normal intensity mode. This agrees well with my own testing, which was limited by the 14 foot depth of our studio. -- I couldn't test to the full 16.4 foot distance, but can safely say that I saw no decrease in flash intensity out to 14 feet. As a marked improvement over the previous F707 model, the F717 features a true hot-shoe external flash connection on top of the camera. This greatly increases the options for connecting an external flash. The F717 also has the ACC Sony accessory flash input socket on the side of the lens. (Note though, that the ACC connection is proprietary to the Sony HVL-F1000 external flash unit.)
Special Recording Modes
Like many Sony digicams, the F717 offers a number of special recording modes, including TIFF, Voice, E-Mail, Exposure Bracketing, and Burst 3. The TIFF option saves a 2,560 x 1.920-pixel uncompressed TIFF version of each image, in addition to the standard JPEG version, at whatever image size you've selected. Voice mode lets you record a five-second sound clip to accompany a still image, with the audio recording starting immediately after the image capture. The E-Mail option records a still image at the 320 x 240-pixel JPEG size for easy e-mail transmission, again in addition to a full-resolution file, at whatever image size you've selected in the menu system. This lets you capture full-resolution images for storage and printing, while at the same time recording smaller versions that you can just drop into an e-mail to share with others. Exposure Bracketing captures three images with one press of the Shutter button (one at the normal exposure, one underexposed, and one overexposed). The amount of variation between exposures is adjustable through the Setup menu, with options of 0.3, 0.7, and 1.0 EV steps. "Burst 3" mode captures a rapid series of three images, at approximately two frames per second. (The actual frame rate and the number of images in the series may be limited by available Memory Stick space, depending on the resolution and quality settings, though.)
Movie Mode
The Movie mode is accessed via the Mode dial on top of the camera, by selecting the film frame icon. You can record moving images with sound at either High Quality (HQX) 320 pixels, or standard quality 320 x 240 and 160 x 112 pixels. MPEG HQX means that you can record for as long as the Memory Stick has space. (The amount of available space varies with the quality setting and resolution.) This is an advance over the F707, which could only record to the limits of card space at its low-quality settings. With the HQX setting, available recording time is reduced somewhat because of the larger file size (just under 6 minutes, even on a 128 MB Memory Stick), but the image quality, frame rate, and audio sampling rate are all significantly increased. Recording begins with a single press of the Shutter button, and ends with a second press. A timer appears in the LCD monitor to let you know how long you've been recording and approximately how much recording time is available.
At the 320 x 240- and 160 x 112-pixel settings, the F717 records in the MPEG EX format, capturing eight frames per second, with audio sampling at 4 KHz. The 320 HQX setting captures 16 frames per second, uses less image compression, and increases the audio sampling rate to 10 KHz. Additionally, movies captured in the 320 HQX setting play back full screen in Playback mode, as opposed to the smaller image displayed for MPEG EX files.
The F717 also provides limited movie editing capabilities. While most digicam users won't be looking for full A/B roll video editing from their cameras, I've often found that I wanted to trim off material from the beginning or end of a video I've recorded, or to extract an interesting bit of action from the middle of a much longer clip. The F717 provides for this via an option on the Playback menu called Divide. As its name suggests, Divide works by dividing movies into two segments. Do this once to trim away spurious material at the front of the clip you're interested in, and do it a second time to remove unwanted footage at the end. Once you've split the movie into parts like this, throw away the segments you don't need, or keep them around to show your viewers how lucky they are that you're only showing them the "interesting" parts. ;-)
After enabling the Divide function through the Playback menu, the F717 starts to play back the movie. You simply press the center of the Four Way Arrow pad to stop the playback where you'd like to make an edit. From there, you can scroll backward or forward frame-by-frame until you find the point where you'd like to divide the movie. You can then either delete the unwanted portion of the movie or keep it on the Memory Stick. As noted, the Divide function is great for "editing" out the best part of a movie file, given that you can make an unlimited number of divides. You just can't put the pieces back together again in the camera. For that, you'll have to use the included MGI VideoWave III SE software, which only runs on Windows computers.
Clip Motion
Through the Setup menu, you can set the movie recording format to "Clip Motion," which turns the F717 into an animation camera, recording up to 10 frames of still images to be played back in succession as an animated GIF. Frames can be captured at any interval, with successive presses of the Shutter button. When you've captured as many photos as you need, you just press the center of the Four Way Arrow pad to tell the camera to finish the sequence. Available image sizes are Normal (160 x 120) and Mobile (120 x 108 - another change from the F707, which recorded Mobile size at 80 x 72), and the number of actual captured frames may vary with image size and available Memory Stick space. (You have a maximum of 10, but could be constrained to fewer if your memory is nearly full.) Files are saved in the GIF format, and are played back with approximately 0.5 second intervals between frames. Unlike Movie mode, the flash is available with Clip Motion. (The shot at right was captured using the Clip Motion feature on Sony's earlier DSC-P1 camera. The function works the same way on the F717.)
Multi Burst
Also accessed through the Movie option under the Setup menu, the F717 features a Multi Burst mode, which captures a rapid burst of 16 images. Once captured, the images are played back as a movie file. Because image capture is so fast, the effect is of a slow-motion sequence. Three frame interval rates are available through the Record menu, 1/7.5, 1/15, and 1/30. You can also set image quality (Fine or Standard), Picture Effects, and Sharpness.
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