Guest curator says: Great colors and I like how the horizon is slightly out of focus, intentional or not.
Guest curator says: Great colors, composition, and shot from a seaplane -- bonus points!
Guest curator says: Unique perspective, good toning and sense of motion.
Guest curator says: Excellent use of shadows.
Guest curator says: Good colors, perfect height for an aerial, maybe 1200 feet up or so.
Guest curator says: Black and white at night -- always a nice combo.
Guest curator says: Amazing colors and composition.
Guest curator says: Love the gritty look and desaturation here. Plus I like the reflections off the glass.
Guest curator says: Love the toning here.
Guest curator says: Great evening shot, nice balance.
Guest curator says: Nice use of minimalism.
Guest curator says: Nice shot from just a few stories up.
Guest curator says: Great use of shadow to help show perspective.
Guest curator says: High altitude shots are sometimes hard to do without losing details, but I like the contours and contrasting colors here.
Guest curator says: Great perspective using foreground volcano and horizon, plus I love the earthy colors.
For this week's round of the Mashable Photo Challenge Guest Series, we wanted to see photos you took from high up in the air. We received more than 600 submissions, ranging from awe-inspiring shots of cities by day and by night, to overhead photographs of blue oceans and high-peak mountains.
"There was a healthy mix of building shots and photos taken from an aircraft," guest curator Adam Senatori said. "I was impressed by the number of submissions and the enthusiasm! This theme definitely resonated with the audience."
See also: Take a 5-Minute Flying Tour of Burning Man
Senatori, a commercial photographer, selected his favorite 15 photographs to be featured in this post. "My selects were based on the key points I mentioned at the outset of the contest: use of shadows, time of day, mixing in buildings and aircraft as vantage points. I was also drawn to a number of submissions that had rich colors, use of window reflections and organic textures."
Check out the rest of the impressive shots here.
Scroll through Senatori's picks above and let us know which ones are your favorites in the comments below. We will announce our next challenge on Thursday.
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Guest curator Adam Senatori, who specializes in aerial photography, makes subtle adjustments to his photos before publishing them. "Adjusting color temperature and contrast are critical to any photo," he says. "But I use most adjustments sparingly, never overdo anything! Subtle is best." He also believes photos taken on an iPhone require different edits than photos taken on a DSLR. "For the iPhone I typically bump up the temp," he says. "I feel that native iPhone shots are on the cool side."
When photographing silhouettes, it can be easy to accidentally overexpose your scene. Guest curator Nicole S. Young uses specific techniques to make sure this doesn't happen. "If your metering mode is set to something such as 'spot metering,' then you'll end up exposing for the subject and overexposing your sky," she said. "So you will need to do one of two things: underexpose your photograph (this will make your subject black and your sky properly exposed), or pre-focus the camera and point it at the sky so it meters for the light in the sky, and not the light from your subject."
Guest curator Alex Koloskov specializes in splash photography. "To get a decent splash shot with only one light source, use clear water (or any other clear liquid) and highlight the background, not the splash itself," he says.
Guest curator Rose Sauquillo takes a lot of shots of walls head-on, but still manages to give them a sense of depth. "Depth can be achieved by adding a vignette, making a colorful subject the focal point, how you compose the shot, or through lighting," she says.
Our guest curator Zak Shelhamer says timing and composition are key elements in good photography. You can use wearable cameras such as the GoPro, the JVC ADIXXION, or the Sony Action Cam to take perfectly timed shots of yourself in action. "Your photos should be able to show viewers what you're seeing and what it feels like to be where you are," Shelhamer says.
Our guest curator Timmy McGurr takes hundreds of photos at a time, but is very selective when choosing his final few to publish. "Just because you shoot a bunch of images from a bunch of different angles doesn't mean you need to post it all," he says. "Learning how to edit and how to decipher what to publish and what not publish is just as important."
Dave Fung and Yena Kim, co-founders of Menswear Dog, use programs and apps like Photoshop, Camera+, Instagram and Hipstamatic regularly. "Effects can make a quirky photo even more whimsical by giving it a vintage feel," they say. "Any number of filters and effects in Camera+ and Photoshop can achieve this."
Guest curator Finn Beales does freelance photography often using just his iPhone. He uses Average Camera Pro and Slow Shutter Cam to take long exposure shots, and then VSCO Cam and AfterLight to add finishing touches to his photos. "Because of the long exposure time, you shouldn't hold your phone in your hands," he says. "Either use a tripod or lean it against something to get sharp results."
Guest curater Dylan Isbell makes sure to steer away from the obvious and capture the things that might be a bit hidden. "Look up, down… all around," he says. "Also look beyond the reflection of yourself to see what play in front and behind you."
Our guest curator Matt Lutton values consistency when he photographs. He uses the same programs each time he edits his photos in order to maintain similar colors and movement. "I try to be as consistent with editing and toning as possible," he says. "These two photos were taken months and hundreds of miles apart, but when next to each other they evoke the same feelings and emotions."
Our Mashable Photo Challenge guest curator Kevin Truong believes light is everything in photography. "Whether it's soft or harsh, from a window or a flash, when used effectively it can beautifully set the mood for the photograph," he says.
Our guest curator Liz Eswein uses two apps to apply filters and text to some of her Instagram photos. Liz says, "One of my favorite editing apps is AfterLight -- it provides such a great array of filters! Also, Over is one of my favorites -- great fonts and steedicons to use on your photos."
Guest curator Brian Difeo uses Snapseed to adjust contrast, sharpness and saturation on his photos before posting them to Instagram. Brian says, "I take photos in the iPhone native app, and I take a LOT of photos so I have many options. In the native app I'll tap the screen to adjust the focus and exposure, and take some photos in HDR too. This way I have variety of photos to choose from before I edit and share on Instagram."
Our Mashable Photo Challenge guest curator Murad Ossmann uses these smartphone photo editing apps to touch up his photos before posting them to Instagram.
Photo courtesy of Murad Ossmann
Murad Ossmann has an Instagram following of almost 270,000, and his feed is full of stunning pictures based on the theme "Follow Me." These photos put a new spin on the traditional travel photo: instead of only photographing landmarks, he features his girlfriend leading him around the world by the hand.
Photo courtesy of Murad Ossmann
One of our guest curators, Santiago PerezGrovas uses natural light to shoot his photos. What began as a limitation (he didn't know how to uses professional flashes) became his signature style.
"In a world of perfection, the production of the photos we see everyday is overwhelming, to the point that everything has to be flawless," says Santiago. "I limit myself to use a simple camera, a model and the available light at the moment."
Image courtesy of Santiago PerezGrovas
Santiago has more than 80,000 followers on Instagram. He posts regular updates around a central theme (shots of models and his friends). His signature style is instantly recognizable.
Image courtesy of Santiago PerezGrovas
The winner of the Photo Challenge Series Dan Evans, Jr., says to use Elements for basic adjustments like cropping, color, contrast and brightness. It is also sophisticated enough to creatively alter a photo without being too complicated.
Image courtesy of Jeremy Cabalona
Homepage image: Instagram, Daz Martin