Starscapes using Topaz Photo Studio and Capture One

I have found that a single photo editor is rarely sufficient for getting the best results. For starscapes, I use a combination of Topaz Photo Studio and Capture One23.

Yosemite Valley night sky

To properly capture the light of the Milky Way, you need a long exposure, but not too long. Let me explain. In the shot above, I wanted the longest exposure I could make that didn’t show star trails. For this shot, I used my Sigma 14-24mm f/2.8 Art lens at 14mm, f/2.8 and 25 seconds at ISO 3200. I always shoot in raw format.

For this 14mm field of view, exposures longer than 25 seconds start to show the star trails, due to the Earth’s rotation. The Topaz Photo Studio (and Topaz Photo AI 4.0.4) has a sharpening feature to rid subject motion. I thought that this feature was the ticket to taking really long starscape exposures, but I thought wrong.

Stars in the night sky move in an arc, and not a straight line. The Topaz programmers that train their AI models give it examples of subjects moving in a straight trajectory. When their program is given photos of a subject moving in an arc, it doesn’t recognize that as being ‘motion’, so no motion blur correction is applied. That sucks.

I hope that at some future date the Topaz people will train their AI motion blur correction with star trails. The following discussion shows you how to process star shots such that motion blur correction would be used, if their AI model gets smarter.

As an aside, I also tried the ON1 Photo RAW editor, including its “Tack Sharp AI” to rid motion blur, but it didn’t rid star motion blur, either.

14mm f/2.8 at 25 seconds, ISO 3200 with no editing

The shot above shows what the stars and landscape look like before editing. I used my Nikon Z9 in ‘manual’ exposure mode. I use a wired remote release and a sturdy tripod.

Launch Topaz Photo Studio from Capture One

Before I do any editing in Capture One, I send the picture to Topaz Photo Studio. Inside the Capture One editor, I right-mouse-click the star shot to get the “Edit With” dialog and select the “Process with Topaz Photo (Studio)”. My Topaz Photo AI works just as well.

Any edits to the raw-format photo will be ignored when you send the picture to Topaz Photo Studio, so don’t bother doing any editing yet. Wait until the photo gets processed in Topaz for more editing back in the Capture One editor later.

The raw (NEF) shot will get converted into another raw format (DNG). Always stick with raw-format for editing, to maintain maximum quality.

Topaz Photo Studio

When Topaz Photo Studio gets launched, it will automatically select the RAW denoise filter when it is given a raw-format photo. For the ISO 3200 shots, the ‘RAW Strong’ denoise strength is preferred. Topaz claims that the RAW denoise filter also automatially removes 'hot' pixels.

It’s possible to add another denoise filter, but usually the ‘RAW denoise’ filter will be sufficient.

Click the ‘100%’ to alter the view magnification

Change the default 100% magnified view, because the selection mask is virtually guaranteed to be WRONG.

Select “Fit” to see the whole shot

Click “Select a filter”

To add another filter, click the “Select a filter”.

Pick the ‘Sharpen’ filter next

Pick the “Motion blur” filter and the “Sky” mask

As I previously mentioned, the above “motion blur” sharpening filter selection is largely wishful thinking. In the future, I hope the Topaz programmers will get some better functionality behind this. It still does sharpen the stars, however.

The AI-generated sky selection mask: pathetic

I’m guessing that the “sky” selection mask is so terrible because it’s a dark nighttime shot. The AI-generated ‘daytime’ selection masks are generally pretty good.

Click on the “Edit selection” to modify the Sky mask

Clean up the Sky mask

As shown above, adjust the mask-selection brush diameter to both add/erase the red ‘sky’ selection mask. When painting the mask is done, click the “Done” button. In theory, the software would then eliminate the star motion trails and leave sharp points of light. The landscape is left untouched by this motion blur mask.

Add another filter (for the landscape)

Add a ‘Sharpen’ filter for the Landscape

Add a sharpening filter for the landscape. With low illumination levels, you probably won’t see too much effect on the landscape. Just like the sky, the landscape AI selection mask will probably be really poor.

Adjust the mask-selection brush

Brush over the entire landscape, then click ‘Done’

It’s possible to remove airplane/satellite tracks…

There is a ‘Remove’ filter option to rid unwanted satellite and airplane light tracks from the sky, but I personally don’t like the results. I save these edits for the Capture One editor, where I use the healing brush to do this operation.

Click “Export to Capture One”

Click the “Export to Capture One” to return to the Capture One editor, where this DNG-format sharpened/noiseless photo will get automatically added to the Capture One catalog.

Now, you’re going to edit the DNG version of the starscape.

Edit the DNG version in Capture One

You can see the edits that I performed in the Capture One editor above, as shown by the red arrows.  I used the healing brush to get rid of the unwanted satellite track.

I left the landscape quite dark, with just a hint of details. You can, of course, lighten the landscape to your liking (mostly increasing the ‘Shadow’ slider).

The sky color temperature (Kelvin) should be adjusted to taste; most people prefer a cooler color temperature.

Star trails close-up with a 60-second exposure

What’s shown above is a star shot after motion-blur removal with Topaz Photo Studio. The trails were unfortunately virtually unaffected by the motion-blur filter. This is why I keep my exposures shorter, and I don’t depend upon software to fix star trails after the fact.

Starscape with editor adjustments to lighten shadows more

I really like how Topaz Photo Studio and Topaz Photo AI rid image noise and also sharpen details. They just don’t work for fixing star trails (yet).