6 replies to this topic

[james7ca]

I took this picture last night of the conjunction between the planet Mars and Leo's Regulus using a fixed tripod (no tracking) and a Nikon Z50 II with a Voigtländer 50mm APO lens. The total integration time was just under one minute using a series of one second exposures while under Bortle 7 skies. During the processing I had problems with the light pollution gradients since Mars is fairly low in the sky even at the very start of astronomical dusk.

 

The three brightest objects in the picture (starting from the lower left) are Regulus (mag. +1.4), Mars (mag. +1.4), and toward upper center the star Algieba (mag. +2.2). The faintest background stars visible in this cropped and resized reproduction are just below magnitude 11. In the full-scale original it's possible to detect magnitude 12 stars and the galaxy NGC 2903 shows up with two branching spiral arms (small).

 

On Monday and Tuesday night (June 16 and 17) Mars will be making its closest approach to Regulus with a separation of just over 45 arc minutes (one and one half times the apparent diameter of the full moon). In my image the two objects are separated by about 1 degree and 10 arc minutes.

 

Image processing with PixInsight, GraXpert, Photoshop, and Affinity Photo (for StarSpikes Pro, to provide a bit of emphasis to the brightest stars).

 

There are additional capture details in the image captions and if you click on the thumbnail/preview you will be able to see the full-sized image as hosted here on CN (1600 x 1200 pixels).

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Edited by james7ca, 16 June 2025 - 06:36 AM.

[james7ca]

Here is a 2X, CFA drizzle using the same data set. A bit noisy but not bad considering the short exposure and the effective 2X enlargement from the original capture. Once again, the limiting magnitude seems to be around 12 and the image scale here is equivalent to having used a 100mm focal length lens.

 

Image processing with PixInsight and Photoshop. The gradient wasn't too bad on this because of the crop and much smaller field of view.

 

There are additional capture details in the image captions and if you click on the thumbnail/preview you will be able to see the full-sized image as hosted here on CN (1480 x 1114 pixels).

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[Arcane1125]

Hi James,

 

Would you mind sharing what your raw image looked like prior to your post-processing? I’m just starting out and want to see what I am up against.

 

Thanks!

[james7ca]

I have no place that I can post the original, RAW files. But, here is what the master integration looked like after an unlinked ScreenTransferFunction (STF) in PixInsight (a simple HistogramTransformation). The scale and cropping isn't exactly the same as for what I posted earlier since I cropped the image during the post processing. Note that the master integration looked completely black and without enabling the unlinked mode for the STF the image would have looked very green.

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Edited by james7ca, 17 June 2025 - 01:04 AM.

[james7ca]

Here is what a single, 1s exposure looked like when opened in Photoshop. This received the standard processing that Photoshop does for any RAW image that comes from the Nikon Z50 II.

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[primeshooter]

Here is a 2X, CFA drizzle using the same data set. A bit noisy but not bad considering the short exposure and the effective 2X enlargement from the original capture. Once again, the limiting magnitude seems to be around 12 and the image scale here is equivalent to having used a 100mm focal length lens.

 

Image processing with PixInsight and Photoshop. The gradient wasn't too bad on this because of the crop and much smaller field of view.

 

There are additional capture details in the image captions and if you click on the thumbnail/preview you will be able to see the full-sized image as hosted here on CN (1480 x 1114 pixels).

Lovely result. I'd be running it through NoiseXterminator with a light setting to finish it. Got a link that shows it in full size glory? The images here are tiny on a 4K monitor.

Edited by primeshooter, 18 June 2025 - 05:47 AM.

[james7ca]

Steven, thanks for the comments and similarly to everyone else for the likes.

 

That image with the 2X drizzle is full size (1:1) as output from the drizzle in PixInsight. Its scale is already beyond what one should probably attempt with a one-shot-color camera. But, if you are viewing it at something higher than 72 dpi then you should be able to zoom your display/browser to better see the result. It's also been processed with BlurXTerminator and any more noise reduction might make it too "plastic."

 

In any case, I was out again on Monday night and I have a better result that was centered on the conjunction between Regulus and Mars. The above drizzle was done on a series of subs where Regulus and Mars were off toward the corner of the frame and that area has more aberrations than you'll find in the center. Plus, on Monday and Tuesday night Mars was even closer to Regulus.

Edited by james7ca, 18 June 2025 - 09:40 AM.