NGC 7000 - Nikon Z6

[sharkmelley]

This is one of the first images from my new (unmodified) Nikon Z6 mirrorless camera.

Full size version is here: http://www.astrobin.com/422848/

Imaging details:

• Unmodified Nikon Z6 on Takahashi Epsilon 180ED (f/2.8 500mm focal length)
• 60 x 2min dithered exposures at ISO 800 (Total integration time 2 hours)
• Sky quality over imaging period averaged SQM 20.87
• Back-of-camera histogram peak was 1/5 from the left-hand-side

The processing goal was to achieve a natural colour image using a traditional astro-imaging workflow, the main steps being:

• Raw file calibration with darks, bias, flats
• Debayering & stacking
• Apply Nikon Z6 white balance
• Apply Nikon Z6 colour correction matrix (Adobe RGB version)
• Background Subtraction to remove light pollution (but no gradient removal was required)
• Apply gamma 2.2 for AdobeRGB colour space
• Colour preserving ArcsinhStretch
• Convert to sRGB

The blue haze at the top right is glare from the nearby Deneb - one of the perils of imaging near a bright star.

I deliberately chose a well-known subject because it makes comparisons easier - particularly regarding H-alpha response.

Mark

Edited August 30, 2019 by sharkmelley

[Brian28]

That's a cracking shot with a standard DSLR .. all be it and expsive one .. 👍

[Ouroboros]

Lovely image that of one of my favourite objects. 

[davew]

That's come out really well Mark. 

I take it all the calibration files worked ok and there were no surprises ?

I'm also assuming the often mentioned focusing array ( On many mirrorless cameras ) isn't showing up under normal astrophotography ? I went looking for it and it wasn't until  -7EV that it appeared. 

Are you using silent shooting and 14 bit ?

So many questions !

Dave.

 

[Allinthehead]

Well that's a very striking image, great colour and detail. Have you given up on the A7s?

[kirkster501]

A fantastic rendition with superb colours. I love your star colours and the bang-on focus and guiding you have achieved.

Superb though it is, I think there is more detail in here that you could tease out with some subtle sharpening with tools such as deconvolution or Multiscale linear transform.  It would be rude not to with such a cracking data set that you have here.

[ollypenrice]

I'd say, 'Mission clearly accomplished.' I think a little local contrast enhancement would give the image a bit more to say for itself without straying from the data but this has to be a great result, especially in a mere 2 hours! (Yes, the Epsilon is fast but even so...)

Olly

Edited August 31, 2019 by ollypenrice

[sharkmelley]

5 hours ago, davew said:

That's come out really well Mark. 

I take it all the calibration files worked ok and there were no surprises ?

I'm also assuming the often mentioned focusing array ( On many mirrorless cameras ) isn't showing up under normal astrophotography ? I went looking for it and it wasn't until  -7EV that it appeared. 

Are you using silent shooting and 14 bit ?

So many questions !

Dave.

 

Thanks.  The master calibration files do show the PDAF (focusing pixel) banding.  The trick seems to be to use dithering to prevent it becoming a problem in the stacked image.  I'm currently using 14bit lossless compression but experiments with silent shutter look very promising.  There's a lot more info over on my Cloudy Nights thread:  Nikon Z6 Testing

4 hours ago, Allinthehead said:

Well that's a very striking image, great colour and detail. Have you given up on the A7s?

I think the Nikon Z6 will be a better match for my Tak Epsilon and is likely to become my main imaging camera.  But I'll continue to use the A7S on the Celestron C11 - the large pixel size is better suited to a long focal length.

3 hours ago, kirkster501 said:

A fantastic rendition with superb colours. I love your star colours and the bang-on focus and guiding you have achieved.

Superb though it is, I think there is more detail in here that you could tease out with some subtle sharpening with tools such as deconvolution or Multiscale linear transform.  It would be rude not to with such a cracking data set that you have here.

Thanks.  I agree that there are further things I could do to improve it.

[davew]

3 minutes ago, sharkmelley said:

Thanks.  The master calibration files do show the PDAF (focusing pixel) banding.  The trick seems to be to use dithering to prevent it becoming a problem in the stacked image.  I'm currently using 14bit lossless compression but experiments with silent shutter look very promising.  There's a lot more info over on my Cloudy Nights thread:  Nikon Z6 Testing

I'll get over there and take a look. I got a Z6 myself and have to admit it's a peach to use doing Starscapes. I've not yet connected it to a scope.

One thing that has really surprised me is how good the focus peaking is. I don't imagine it would help you though,

Dave.