I noticed that you always stop down your 2.8 aperture—does it cause stars to bloom too much at f/2?
I recently tried the Samyang 85mm, and at f/2.8, the red channel is noticeably out of focus compared to the green and blue.
And it expands, and the gap between channels increases, making it harder to focus: the Samyang is extremely sensitive to shifting the focus ring.
The 135mm also has an issue with red halos, which is especially noticeable when using a CLS filter. I've almost developed a strategy of focusing on the red channel (because hydrogen nebulae are the most accessible) and then combining it with the other channels.
At one point, I considered the 85mm for astrophotography, but I realized it's really not suited for that, it seems.
28 Dec, 2025
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I recently tried the Samyang 85mm, and at f/2.8, the red channel is noticeably out of focus compared to the green and blue.
The 135mm also has an issue with red halos, which is especially noticeable when using a CLS filter. I've almost developed a strategy of focusing on the red channel (because hydrogen nebulae are the most accessible) and then combining it with the other channels.
At one point, I considered the 85mm for astrophotography, but I realized it's really not suited for that, it seems.
Comments are available only to registered users. Register or log in to leave a comment.