Went out on a rare clear night to a wetlands near me to take some photos of the stars. As it was so dark, and the stars are so small, I had to rely on the focus peaking function of my camera to tell if the stars were in focus or not.

I’ve got home and started to process the photos, and I’ve found out that despite the camera telling me that they were in focus, they clearly weren’t.

Hey ho, what’s a wasted few hours in the freezing cold between friends…

  • XeroxCool@lemmy.world
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    9 months ago

    Astronomers like using eye patches to minimize the risk of having both eyes getting bleached. I set my dslr to the lowest brightness and swapped it to a red-only color pallete for menus, but the image result can certainly still be blinding while I do some f/2.8 5s ISO 25600 framing shots. If you can’t dim it enough and don’t have a red menu option, maybe some tint film or even sunglasses could help. Maybe red plastic wrap for style points. Red doesn’t bleach your eyes.

    As for focus, even on my crop sensor dslr with a 11-16mm lens, I can use live preview and 10x screen zoom to find some bright stars to hone focus. For this picture, it doesn’t get better than Sirius just to the left and down of this frame. Planets are good for the first attempt at focus if there’s no lens markings or manual focus is still electronic, but any appreciable zoom makes them lose usefulness as they become disks instead of points.

    Phones have come a long way but focus on those is still the most frustrating thing. The native app doesn’t allow manual focus on my pixels but the pro mode apps don’t have the 4 minute astro modes.

    And yes, bleaching is the issue. Your pupils take a few seconds to dilate, but light will bleach the rhodopsin in your receptors. It takes more time to refill rhodopsin stores and dope your receptors again which is where the “dark adaptation takes 20 minutes” comes from.

    I just came back from the grand canyon/arizona and that is a place you don’t want to lose night vision. So much to see, even in winter with the thin side of the Milky way. Happy trails. Pack your red flashlight

    • Tippon@lemmy.dbzer0.comOP
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      8 months ago

      Thanks for replying, sorry about the slow reply :)

      I didn’t know that you could change the colour settings for the screen, other than adjusting the brightness. Unfortunately, it’s not something that’s available on my Sony a6000. I have bought a cheap pair of red sunglasses to see if they help though :)

      The a6000 has a live preview which zooms to 11 (fans of Spinal Tap perhaps? ), and it works fairly well. Using it on planets is difficult, as the planets move out of the small window very quickly, but for the stars it’s usually great. I just didn’t use it this time as the camera said that the focus was correct.

      Never mind, I just need to wait for the next clear night now :)

      • XeroxCool@lemmy.world
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        8 months ago

        Ah, sounds like you’ve got a handle on it then. I use a manual slr nikon lens on a dslr Canon body so I’m used to the focus rating being wrong. I understand the frustration of getting everything set up and the result being less than expected.

        Funny, your last sentence is the reason my go-to forum is named cloudynights. We don’t post on clear nights!