You’re welcome! I happened to have just come back in from gazing a bit. I highly recommend binoculars as an introductory to optics because they’re very portable, very easy to set up, and offer a brighter view for the money than a telescope. The tradeoff is much less magnification.
7x35, 8x42, and 10x50 are the recommended sizes for handheld viewing. If you end up getting a tripod and adapter (the hinge on any of these first 3 will have a threaded receiver too), 16x70s, 20x80s, or similar ones marketed as astro binos are feasible. Leave the 10x25s and 20x50s home for daytime use.
The important thing is the implied 3rd number form those specs. The first number is the magnification, the second number is the outer lens diameter in mm. If you divide the outer lens by the mag, you get the eye-side lens diameter. 35/7=5mm, 42/8=5.25, 50/10=5. This is the real key to night use. Pupils dilate to a maximum of 7mm, shrinking as you age. The bigger the bino aperture, the better use of your pupil aperture. 5mm is where the cost/benefit lines up best in the market, so that’s why those first three are the recommended specs. Meanwhile, the cheap and common 10x25s and 20x50s have just 2.5mm apertures, closer to your daylight pupil size. They’ll be dim. The 16x70s and 20x80s are 4.3 and 4.0mm respectively, so you started losing brightness to cost there as you approach having two telescopes bolted together, but using two eyes is still advantageous.
I’m rusty on the popular model lines, but I was choosing between Nikon Acculon and Nikon Action Extreme years back. Nikon is one of the best lens manufacturers. Binoculars use a prism inside to flip the image right side up and that glass is even more important than the lens, and these two models excel there, too. I paid more for the AE because it has better durability and water resistance. I’m reasonably careful, but I don’t take precautions with mine. I’m often stargazing on a sandy beach somewhere as bodies of water mean no light pollution in that direction. Sand, humidity, salt spray, temperature swings, my AEs don’t care. They’ve been on many plane rides in both my backpack and my suitcase.
But whatever 5mm aperture binos you can find will open up the sky for you. For size, I’ve tried both the 7x35 and 10x50 AEs (so equivalent comparison). I prefer the 10s for notably more zoom, although it’s harder to hold steady. They’re ~50% larger and heavier though. When scouting around for objects like those on the Messier catalogue, they’re all going to be small blobs, so the 40% better mag is worth to me. But either way, the number of stars seen with that brightening effect is magnificent. The 7s let you detect more of our galactic structure though when looking into the Milky Way band. But for that, I built Nikon 2x56s with a 3d printed shell and obsolete ~2003 Nikon 2x camera multipliers from an obsolete 4mp camera model.
I’m northern hemisphere. Andromeda galaxy, Leo cluster, and lagoon nebula are easy targets in the summer. Orion nebula, beehive open cluster, in the winter and I think perseus open cluster. Helix nebula is probably the most defined thing I can spot if the skies are dark (bortle 4 max) in the summer, as an obvious gray disk.
Gonna touch on light real quick. Lightpollutionmap.info is my go-to site. Bortle scale is 1-9. Higher is worse. Class 2/3 is worth my time. That’s the blue regions. I’ll go further for gray class 1/2. Getting to no-color 1 is usually difficult.
Night adaptation. Your pupils dilate in seconds, but your eyes are also doped with “rhodopsin”. It takes 20 minutes for rhodopsin to to fully re-dope your receptors for night vision. This is why indoors seems so dark for a fee minutes when entering and why going outdoors seems so bright for a few minutes. But for this level of dark adaptation, assume you need the full 20 mins. Red light will not affect it, but blue/purple/UV will, which is part of what makes lights and screens white. Phone screen, flashlights, headlights, white street lights will affect it. Avoid all that. Phones with reddish screen settings called various things like low-blue, night shade, f.lux, etc do help. You’ll probably want a phone app to help locate things. SkySafari is my preference
Thanks for sharing! I never thought about using binoculars for stargazing. Which magnification makes a significant difference?
You’re welcome! I happened to have just come back in from gazing a bit. I highly recommend binoculars as an introductory to optics because they’re very portable, very easy to set up, and offer a brighter view for the money than a telescope. The tradeoff is much less magnification.
7x35, 8x42, and 10x50 are the recommended sizes for handheld viewing. If you end up getting a tripod and adapter (the hinge on any of these first 3 will have a threaded receiver too), 16x70s, 20x80s, or similar ones marketed as astro binos are feasible. Leave the 10x25s and 20x50s home for daytime use.
The important thing is the implied 3rd number form those specs. The first number is the magnification, the second number is the outer lens diameter in mm. If you divide the outer lens by the mag, you get the eye-side lens diameter. 35/7=5mm, 42/8=5.25, 50/10=5. This is the real key to night use. Pupils dilate to a maximum of 7mm, shrinking as you age. The bigger the bino aperture, the better use of your pupil aperture. 5mm is where the cost/benefit lines up best in the market, so that’s why those first three are the recommended specs. Meanwhile, the cheap and common 10x25s and 20x50s have just 2.5mm apertures, closer to your daylight pupil size. They’ll be dim. The 16x70s and 20x80s are 4.3 and 4.0mm respectively, so you started losing brightness to cost there as you approach having two telescopes bolted together, but using two eyes is still advantageous.
I’m rusty on the popular model lines, but I was choosing between Nikon Acculon and Nikon Action Extreme years back. Nikon is one of the best lens manufacturers. Binoculars use a prism inside to flip the image right side up and that glass is even more important than the lens, and these two models excel there, too. I paid more for the AE because it has better durability and water resistance. I’m reasonably careful, but I don’t take precautions with mine. I’m often stargazing on a sandy beach somewhere as bodies of water mean no light pollution in that direction. Sand, humidity, salt spray, temperature swings, my AEs don’t care. They’ve been on many plane rides in both my backpack and my suitcase.
But whatever 5mm aperture binos you can find will open up the sky for you. For size, I’ve tried both the 7x35 and 10x50 AEs (so equivalent comparison). I prefer the 10s for notably more zoom, although it’s harder to hold steady. They’re ~50% larger and heavier though. When scouting around for objects like those on the Messier catalogue, they’re all going to be small blobs, so the 40% better mag is worth to me. But either way, the number of stars seen with that brightening effect is magnificent. The 7s let you detect more of our galactic structure though when looking into the Milky Way band. But for that, I built Nikon 2x56s with a 3d printed shell and obsolete ~2003 Nikon 2x camera multipliers from an obsolete 4mp camera model.
I’m northern hemisphere. Andromeda galaxy, Leo cluster, and lagoon nebula are easy targets in the summer. Orion nebula, beehive open cluster, in the winter and I think perseus open cluster. Helix nebula is probably the most defined thing I can spot if the skies are dark (bortle 4 max) in the summer, as an obvious gray disk.
Gonna touch on light real quick. Lightpollutionmap.info is my go-to site. Bortle scale is 1-9. Higher is worse. Class 2/3 is worth my time. That’s the blue regions. I’ll go further for gray class 1/2. Getting to no-color 1 is usually difficult.
Night adaptation. Your pupils dilate in seconds, but your eyes are also doped with “rhodopsin”. It takes 20 minutes for rhodopsin to to fully re-dope your receptors for night vision. This is why indoors seems so dark for a fee minutes when entering and why going outdoors seems so bright for a few minutes. But for this level of dark adaptation, assume you need the full 20 mins. Red light will not affect it, but blue/purple/UV will, which is part of what makes lights and screens white. Phone screen, flashlights, headlights, white street lights will affect it. Avoid all that. Phones with reddish screen settings called various things like low-blue, night shade, f.lux, etc do help. You’ll probably want a phone app to help locate things. SkySafari is my preference