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Hubble scientists revisit an incredible image of Veil Nebula, showing off new details

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Hubble scientists revisit an incredible image of Veil Nebula, showing off new details

In 2015, the Hubble Space Telescope captured an image of the Veil Nebula. NASA has revisited this image and applied new processing techniques, bringing out even finer details of the nebula.

NASA, ESA/Hubble and Z. Levay have been able to bring out additional details in the ionized gas that makes up the threads and filaments of the nebula. Observations taken by Hubble’s Wide Field Camera 3 instrument using five different filters were combined with new post-processing methods to create the new image. You can see enhanced details of emissions from doubly ionized oxygen (seen in the image as blue colors), ionized hydrogen, ionized sulfur (green) and ionized nitrogen (seen as reds in the photo).

This close-up image of the Veil Nebula was first captured in 2015. It has been reprocessed to show a better view of the nebula and its filaments of ionized gas. The ionized gas is all that remains of a supernova that about 20 times the mass of the Sun. ‘The fast-moving blast wave from the ancient explosion is plowing into a wall of cool, denser interstellar gas, emitting light. The nebula lies along the edge of a large bubble of low-density gas that was blown into space by the dying star prior to its self-detonation.’ Image credit: ESA/Hubble & NASA, Z. Levay

The Veil Nebula is about 2,100 light-years from Earth in the constellation of Cygnus, otherwise known as the ‘Swan.’ As NASA writes, in astronomical terms, Cygnus is a relatively close neighbor.

100% crop of the above image. To download the massive image for yourself

Astronomer William Herschel first identified the Veil Nebula way back in 1784. In 1904, Herschel’s work was followed by Williamina Fleming’s discovery of a fainter portion of the nebula, known as Pickering’s Triangle, named after the director of the Harvard College Observatory where Fleming worked. If you’d like to view the Veil Nebula for yourself, the best observation time is early autumn in the northern hemisphere and early spring in the southern hemisphere. The nebula is not visible to the naked eye, but it can be seen through a telescope or binoculars under dark sky conditions. If you have a nebula filter, it will help brighten the Veil’s appearance and allow you to see additional detail.

The Veil Nebula is a visible portion of the Cygnus Loop, which is the remnant of a supernova formed about 10,000 years ago. The Veil Nebula formed through the death of a massive star, which possessed roughly 20 times the mass of the Sun. Like other stars of that size, it had a relatively short lifespan and died with a massive release of energy. The energy and debris from this supernova form the Veil Nebula’s tendrils of ionized gas.

The 2015 version of the image of the Veil Nebula. Image credit: NASA/ESA/Hubble Heritage Team

The original image and the reprocessed version show only a small section of the Veil Nebula, which is continually expanding. The entire nebula is 110 light-years across, covering about six full moons’ worth of the night sky as viewed from Earth. The section we see in the shot from Hubble, which is a six-image composite, is about two light-years across.

Back in 2015, when showing off its new image of the Veil Nebula, NASA also shared a couple of neat videos. The videos haven’t been redone with the latest processed image, but they’re nonetheless worth checking out again.

You can learn more about the Veil Nebula by visiting Hubble’s Caldwell catalog. For further reading on some of Hubble’s amazing images and discoveries, check out some of our prior coverage:

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Pentax K-1 and K-1 II firmware updates include astrophotography features (depending on where you live)

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Pentax K-1 and K-1 II firmware updates include astrophotography features (depending on where you live)


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Yesterday, Ricoh quietly released firmware 2.50 for its Pentax K-1 and K-1 II DSLRs. However, the features you can expect to gain from this update may depend on your geography.

Ricoh’s English-language firmware pages for the K-1 and K-1 II state that firmware 2.50 delivers “Improved stability for general performance.”

However, astute Pentax users noted that Ricoh’s Japanese-language firmware pages (translation) indicate that the update also includes a limited feature called “Astronomical Photo Assist,” a collection of three new features designed for astrophotography: Star AF, remote control focus fine adjustment, and astronomical image processing.

Star AF is intended to automate focusing on stars when using autofocus lenses. Rather than manually focusing on a bright star and changing your composition, it promises to let you compose your shot and let the camera focus.

Remote control fine adjustment allows users to adjust focus without touching the lens and requires Pentax’s optional O-RC1 remote. Astronomical image processing will enable users to make in-camera adjustments to astrophotography images, including shading correction, fogging correction, background darkness, star brightness, celestial clarity, and fringe correction.

Astronomical image processing on the K-1 and K-1 II will enable users to make in-camera adjustments to astrophotography images, including shading correction, fogging correction, background darkness, star brightness, celestial clarity, and fringe correction.

According to Ricoh, Astronomical Photo Assist is a premium feature that must be purchased and costs ¥11,000 for an activation key (about $70 at current exchange rates).

Although these astrophotography features appear to be Japan-only for now, a Ricoh representative tells us, “Ricoh Imaging Americas confirmed that the premium firmware features for the PENTAX K-1 and PENTAX K-1 Mark II will eventually be available to US customers.”

Firmware update 2.50 for both the K-1 and K-1 II is available for download from Ricoh’s website.



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On this day 2017: Nikon launches D850

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On this day 2017: Nikon launches D850


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As part of our twenty fifth anniversary, we’re looking back at some of the most significant cameras launched and reviewed during that period. Today’s pick was launched seven years ago today* and yet we’re only quite recently stepping out of its shadow.

The Nikon D850 is likely to be remembered as the high watermark of DSLR technology. We may yet still see impressive developments from Ricoh in the future (we’d love to see a significantly upgraded Pentax K-1 III), but the D850 was perhaps the green flash as the sun set on the DSLR as the dominant technology in the market.

Click here to read our Nikon D850 review

Why do we think it was such a big deal? Because it got just about everything right. Its 45MP sensor brought dual conversion gain to high pixel count sensors, meaning excellent dynamic range at base ISO and lower noise at high ISOs. Its autofocus system was one of the best we’ve ever seen on a DSLR: easy to use and highly dependable, with a good level of coverage. And then there was a body and user interface honed by years of iterative refinement, that made it easy to get the most out of the camera.

None of this is meant as a slight towards the other late-period DSLRs but the likes of Canon’s EOS 5DS and 5DSR didn’t present quite such a complete package of AF tracking, daylight DR and low-light quality as the Nikon did. With its ability to shoot at up to 9fps (if you used the optional battery grip), the D850 started to chip away at the idea that high megapixel cameras were specialized landscape and studio tools that would struggle with movement or less-than-perfect lighting. And that’s without even considering its 4K video capabilities.

In the seven years since the D850 was launched, mirrorless cameras have eclipsed most areas in which DSLRs once held the advantage. For example, the Z8 can shoot faster, autofocus more with more accuracy and precision, across a wider area of the frame and do so while shooting at much faster rates.

But, even though it outshines the D850 in most regards, the Z8 is still based around what we believe is a (significant) evolution of the same sensor, and its reputation still looms large enough for Nikon to explicitly market the Z8 as its “true successor.”

Nikon D850 sample gallery

Sample gallery
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*Actually seven years ago yesterday: we had to delay this article for a day to focus on the publishing the Z6III studio scene: the latest cameras taking precedence over our anniversary content.



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Nikon Z6III added to studio scene, making image quality clear

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Nikon Z6III added to studio scene, making image quality clear


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Photo: Richard Butler

We’ve just received a production Nikon Z6III and took it into our studio immediately to get a sense for how the sensor really performs.

Dynamic range tests have already been conducted, but these only give a limited insight into the image quality as a whole. As expected, our Exposure Latitude test – which mimics the effect of reducing exposure to capture a bright sunrise or sunset, then making use of the deep shadows – shows a difference if you use the very deepest shadows, just as the numerical DR tests imply.

Likewise, our ISO Invariance test shows there’s more of a benefit to be had from applying more amplification by raising the ISO setting to overcome the read noise, than there was in the Z6 II. This means there’s a bigger improvement when you move up to the higher gain step of the dual conversion gain sensor but, as with the Z6 II, little more to be gained beyond that.

These are pushing at the extreme of the sensor’s performance though. For most everyday photography, you don’t use the deepest shadows of the Raw files, so differences in read noise between sensors don’t play much of a role. In most of the tones of an image, sensor size plays a huge role, along with any (pretty rare) differences in light capturing efficiency.

Image Comparison
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As expected, the standard exposures look identical to those of the Z6 II. There are similar (or better) levels of detail at low ISO, in both JPEG and Raw. At higher ISO, the Z6III still looks essentially the same as the Z6II. Its fractionally higher level of read noise finally comes back to have an impact at very, very high ISO settings.

Overall, then, there is a read noise price to be paid for the camera’s faster sensor, in a way that slightly blunts the ultimate flexibility of the Raw files at low ISO and that results in fractionally more noise at ultra-high ISOs. But we suspect most people will more than happily pay this small price in return for a big boost in performance.



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