JPEG Image Size & Quality
Standard Test Scene
The Optio 550 allows you to select image size and quality separately. For image size you have the following options; 2592 x 1944, 2048 x 1536, 1600 x 1200, 1024 x 768 and 640 x 480. For image quality there are three levels of JPEG compression represented by one, two or three stars (best) plus a TIFF uncompressed option. It's interesting that Pentax has chosen to use a larger-than-the-rest (other 5 mp digital cameras) 2592 x 1944 image size, this pushes the output pixel count to just greater than 5 million (the rest are 4.92 million).
To give an impression of what some of the combinations of image size and quality produce the table below is a cross reference of some of them:
- 2592 x 1944 TIFF
- 2592 x 1944 JPEG
- 2592 x 1944 JPEG
- 2592 x 1944 JPEG
- 1600 x 1200 JPEG
- 1600 x 1200 JPEG
- 1024 x 768 JPEG
Images below are cropped 240 x 100 area of the image magnified
200% (nearest neighbour).
|2592 x 1944|
14,873 KB - not available for download
|2048 x 1536|
|1600 x 1200|
|1024 x 768|
As we normally find highest quality JPEG (three star in the case of the Optio 550) is virtually indistinguishable from the TIFF image. However a three star full resolution image weighs in at 2.7 MB, not a small file by anyone's standards. Most people will opt for the two star quality where there are some very slight artifacts around detail edges, but nothing that would be particularly noticeable at reasonable viewing or print sizes. The Optio 550 appears not to apply any interpolation to downsampled images, hence the jagged appearance of reduced resolution images (such as the 1024 x 768 above).
The Optio 550 allows you to modify the contrast, saturation or sharpness levels which are applied to the image before it is converted to its output format. It provides just three levels of adjustment for each parameter (-1,0,+1) which is a surprise because I would have expected more latitude on a prosumer digital.
Image parameters: Contrast
Image parameters: Saturation
Image parameters: Sharpness
|Sharpness, 100% crop|
Nikon turns 100 years old today, and the company is celebrating with a wacky music video, some tributes to its history, and a new vision presented by president Kazuo Ushida.
Phottix just released the Premio Parabolic Umbrellas series, replacing their Para-Pro line with a stronger, deeper and better made set of parabolic umbrellas.
The Moto Z2 is Motorola's first dual-camera smartphone and, compared to its predecessor, comes with a number of improvements and new camera features.
Researchers at Stanford have revealed a new '4D camera system' built for robots. The system is based on the same light field tech that allowed Lytro cameras to refocus images after they were taken.
If you want 'beautiful rendition' from your lenses, follow this simple rule: only buy classic low-element prime lenses with lead glass elements—everything else is junk.
In an interview with CNBC, Leica Chairman Andreas Kaufmann said he dreams of a 'true Leica phone,' and hinted at what's next for the Leica and Huawei partnership.
Wildlife and nature photographer Peter Mather tells the story behind this exceptional shot of a mama grizzly and her cub searching for salmon in Yukon, Canada.
Popular YouTube channel TastyTuts has put together this 33-video Beginner's Guide to Adobe Photoshop—a godsend for anybody who wants to learn Photoshop from scratch.
The long anticipated replacement for the popular Rode VideoMic Pro is almost ready for shipping. The price of the upgraded VideoMic Pro+ will be £290/$300 when it goes on sale in mid-August.
A new iOS app called Explorest wants to help you find new locations to shoot. It's limited to Singapore for now, but the app is packed full of useful location scouting features.
Nikon's D850 development announcement is extremely light on details, so we assembled a wish list of upgrades and features we'd love to see.
Nikon has announced the development of the long-awaited replacement to its full-frame D810: the D850. Nikon says that the D850 will build on the strengths of its predecessor and offer 'new technologies, features and performance enhancements.'
Lens manufacturer Voigtlander has introduced a 65mm F2 macro lens for Sony E-mount that it says "rates as one of the finest in the history of Voigtländer."
The UK released a preview of their upcoming drone safety regulations, and it looks like drone pilots will have to both register their device and pass safety awareness tests.
National Geographic photographer Bob Holmes talks about light, and why you need to learn how to 'see' and not just 'look' at your subject.
Photographer Alessandro Barteletti shares the story behind his National Geographic Italia cover, shot with a 10-year-old DSLR and an iPhone flashlight.
Fashion catalog photographers in China have some next-level models to work with. In this video, you see one model hitting 30 poses in 15 seconds as the photographer snaps away.
Photographer Paul Adshead breaks down 11 photography-related smartphone apps he couldn't live without—from a pocket light meter to a lighting diagram app.
Fast-growing Chinese flash brand Godox is teasing a brand new flash trigger... for smartphones. The Godox A1 is a 'phone flash system' that can act as both flash and 2.4GHz trigger.
On July 12, Canon opened its newest Technology and Support Center, designed to serve the motion picture industry, in Burbank, CA. DPReview got a sneak peak and takes you behind the scenes.
The Sigma 14mm F1.8 Art is truly one-of-a-kind. It offers the fastest aperture of any lens that shares its focal length, produces beautiful sunstars and is incredibly sharp to boot. If you're in the market for a fast ultrawide prime, this looks to be the one to get.
In this article, expert macro photographer Thomas Shahan shares advice for successful closeup photography of bugs, insects and small animals.
DJI's new firmware makes it difficult to fly in restricted airspace, even when you have proper clearance. Is DJI placing themselves between professionals and the FAA?
Go behind the scenes with National Geographic photographer Renan Ozturk and see what it takes to capture a dangerous, harrowing, stunning Nat Geo photo essay.
Erez Marom tells the story behind this ominous photo of the sand 'reaching up' towards the mountains at Skagsanden beach in Norway. He calls this photo 'Torment.'
DPReview staffer Carey Rose has taken the Panasonic Leica DG 15mm F1.7 along for everything from a city-side boat ride to a bachelor party across the mountains. Find out how the little Leica fared.
Canon just unveiled the largest 12-ink printer on the market. The new imagePROGRAF PRO-6000 printer can make prints from 17 all the way up to 60 inches wide.
"Standing in one of the holiest places on earth, I felt uneasy," writes Wired's Jason Parham. "Most of my fellow visitors, I realized with a brief bloom of nausea, were taking selfies."
Christopher Nolan's Dunkirk has been receiving great reviews, but it's a challenge to see it in its full glory. This handy infographic reveals the aspect ratio chaos that is wrought as the industry retreats from film.
Anti-bullying organization Ditch the Label's Annual Bullying Survey 2017 reveals yet again that Instagram, more so than any other social network, has the worst effect on youth mental health.