Nikon d810a -- astrophotograhy

[GaryLH]

http://www.dpreview.com/articles/5786202951/nikon-d810a-astrophotography-camera

Interesting specialty item from Nikon. Never would have suspected there was a jacket big enough to release a specialized camera.

Gary

 

[Samouraï]

Pretty cool, no? Is there anyone on the board that would make serious use of a camera like this?

Pretty expensive too. Two (three-ish) near-$4000 bodies from Canon and Nikon in the past week. I wonder what else we'll be seeing at CP+.

 

[crosseyed-cricket]

The Canon 60Da has had some success in the astrophotography community, so I suspect that Nikon is trying to one-up the game with a full-frame version.

There are two (main) issues with using a DSLR for astrophotography

1. Red sensitivity in the ~650nm wavelength range (needed for many emission nebulas)
2. Thermal noise

Both Canon and Nikon have addressed #1, but neither take care of #2. Especially in warmer climates, thermal noise from the sensor on long exposures can overwhelm the gains achieved by the increased red sensitivity.

I've seen some great images from the Canon, so I will be interested to see what people can do with this Nikon.

For the money, I chose to invest in a thermoelectrically (TEC) cooled CCD designed with wide spectrum and specific for astrophotography. The downside, is that camera can't be used for anything else.

 

[pvdhaar]

Cool camera indeed.. pity that it's so expensive, and for the level at which I dabble in astrophotography it's just way too much.

I'll stick to my regular DSLR, and wing it with stacking and dark-frames/flatfield-frames to separate the light from the noise..

By the way, there's still lots of astrophotography that can be done with a regular IR cut filter in your DSLR. For example; the attachment below: 90mm f2.8 ISO3200 64 x 3" stacked

 

[crosseyed-cricket]

You're absolutely right...many objects do not benefit from the increased red sensitivity in these astro modified cameras. It is mainly Hydrogen-rich areas (like the Orion Nebula, etc) that show more detail.

Even in those areas, a non-astro DSLR will still capture red/Hydrogen emission nebulas...but will take longer exposures to do so, and may not show as many subtle details.

Stacking can help reduce the noise in an image, but I have found in the Summer months here in Texas and Oklahoma, that the noise coming from heat from the sensor (and ambient heat) simply cannot be removed completely. So, for me, TEC cooling is absolutely critical.

The following pictures are not especially Hydrogen-rich, and would not benefit much from a camera like the D810a in that regard. These were both with a Sony A7 DSLR (not IR modified).

The Andromeda Galaxy image is actually pretty noisy, since it was taken in August (hot!)...but fortunately, the dense starfield helps reduce the appearance of that noise.



Comet Lovejoy and the Pleiades by crosseyed-cricket, on Flickr


M31 - Andromeda by crosseyed-cricket, on Flickr

 

[noimmunity]

Cool!
Faced with enormously declining sales, camera manufacturers are trying a postfordist business model, making camera that appeal to specific niches.
"Horses for courses" seems to be their rallying cry.

 

[pvdhaar]

Beautiful images David!

I could only wish that my biggest problem would be one of thermal noise. I live in a densely populated area with severe light pollution. Unless the atmosphere is ultra clean (no dust, low humidity) scattered light tends to drown out everything..

 

[crosseyed-cricket]

Thanks Peter,

Dallas, Texas is also severely light polluted...which is why I had to budget the cost of gasoline for a 100 mile drive each way to darker skies in the cost of my camera! 🙂