8x42 roofs?

[jjohnson3803]

I have a little extra astro money on hand and I'm seriously considering getting a pair of 8x42 roof prism binos.  I have 15x70 IF - kind of heavy, really need a tripod, Aculon 10x50s - they're ok but a little hard for me to keep steady, and a pair of 7x50 military surplus porros - built like a tank, less bouncy views, but maybe a little low on the mag.

So what says the collective mind?  Would 8x42s be redundant, considering what I have?  There's a good chance I'd sell off one or more of the others if the 8x42s did the trick.

 

[The60mmKid]

I like them very much. Underrated as handheld binoculars for astronomy, in my opinion. I don't think you'd find them redundant. How dark are your skies, out of curiosity?

Are you interested particularly in 8x42 roofs or more broadly in binoculars of this general size/magnification class?

[jjohnson3803]

1 hour ago, The60mmKid said:

How dark are your skies, out of curiosity?

Short answer:  Not.  I'm in a suburban to bright suburban zone.  I do get out to dark sites though, either specifically to observe or when I get a chance while traveling for business.

I'm mainly wondering about the class to cut down the bouncy stars sans tripod, but have a decent amount of aperture.  I've never owned a pair of roofs and I'll be near a store with a boatload of Vortexes on display while traveling in a couple of weeks.  Always nice to bring back a souvenir.  🙂

[The60mmKid]

Nice! I think 8x42 might suit your purposes well. I think I'd part with 7x50 first since the 7mm exit pupil is only fully utilized under dark skies. I, too, don't find 10x50 ideal, preferring either smaller or larger binoculars.

[Louis D]

I've been observing with Meade Safari Pro porro-prism 8x42 bins for over 25 years and still love them.  I managed to snag a second pair off of ebay a couple of years ago as a backup pair.  I like their 65 degree field and 18mm of usable eye relief.

[Second Time Around]

This is what I posted in another topic about 7x50s - although I'm not suggesting you're old! 🙂

"As you said, as you age your maximum pupil size will almost certainly diminish and so you won't benefit from the full 50mm aperture. This would of course need a pupil size of 50 divided by 7, so over 7mm. As I'm sure you know, but others might not, that's more typical of a youngster.

The same applies when you're in towns and cities where the extra lights mean that even a young person's pupils are most unlikely to open to 7mm. 

If in either circumstance your pupil size opens to only say 5mm you might as well buy 7x35 binoculars. These will be smaller and lighter, and also probably have a wider field of view.

Another point to consider is that experiments have shown that magnification is even more important than aperture in seeing faint stars. This has been discussed at length on the Cloudy Nights binocular forum.

However, as you said, if you go up to 10x50s they'll be harder to hold steady.

Short of buying expensive image stabilised binoculars, a good compromise might be 8x40s or 8x42s. Strangely enough, many of these will have a wider field of view than 7x50s. Indeed, in practice, many 10x50s have a wider field of view than 7x50s."

Edited March 4 by Second Time Around

[jjohnson3803]

Last time I had an eye exam, my doc said, "Nah, they're wide open" when I asked about my pupils dilating.  He didn't actually give me a number though, so I guess I should ask specifically.

 

[F15Rules]

I have Vixen pairs at 7x50 (porros) and  8x32 (roofs). Both high quality and made in Japan.

Both are very different animals..the 7x50s are very heavy, and benefit greatly from a tripod (I have mine on a pistol trigger grip and aluminium tripod, on which they are superb). They have a 7.3 degree field, great contrast and pinpoint stars across most of the field.

 

The 8x32s Apex Pro roofs are a handheld delight..compact, solid but quite light and very comfortable to hold for long periods - and also with a nice 7.5 degree fov..but it feels quite a bit wider than the 7x50s.

I think an 8x42 pair of roofs would fit very well with your current pairs..they would be very comfortable, not tiring for extended sessions, and stunning in darker skies on clusters, milky way etc.

And also excellent for bird and wildlife watching.

Good luck with your choice!

Dave

[The60mmKid]

2 hours ago, Second Time Around said:

This is what I posted in another topic - although I'm not suggesting you're old! 🙂

"As you said, as you age your maximum pupil size will almost certainly diminish and so you won't benefit from the full 50mm aperture. This would of course need a pupil size of 50 divided by 7, so over 7mm. As I'm sure you know, but others might not, that's more typical of a youngster.

The same applies when you're in towns and cities where the extra lights mean that even a young person's pupils are most unlikely to open to 7mm. 

If in either circumstance your pupil size opens to only say 5mm you might as well buy 7x35 binoculars. These will be smaller and lighter, and also probably have a wider field of view.

Another point to consider is that experiments have shown that magnification is even more important than aperture in seeing faint stars. This has been discussed at length on the Cloudy Nights binocular forum.

However, as you said, if you go up to 10x50s they'll be harder to hold steady.

Short of buying expensive image stabilised binoculars, a good compromise might be 8x40s or 8x42s. Strangely enough, many of these will have a wider field of view than 7x50s. Indeed, in practice, many 10x50s have a wider field of view than 7x50s."

Important points here. Even if our pupils are capable of dilating to 7mm, they won't do that under light-polluted conditions. That requires darkness, which is why we allow our eyes to dark adapt. Under light-polluted conditions, using binoculars with a smaller exit pupil means that we're not "wasting" light with an exit pupil from the binoculars that is larger than our eyes' not-fully-dilated pupils. @Second Time Around offers a helpful explanation above.

This is why binoculars with a 7mm exit pupil (e.g., 7x50, 10x70) require dark skies to use to their potential. Because dark skies allow our pupils to dilate fully. Under light-polluted conditions, those 8x42s are more able to perform to their fullest than 7x50s.

Edited February 22 by The60mmKid

[Nakedgun]

8 hours ago, jjohnson3803 said:

I have a little extra astro money on hand and I'm seriously considering getting a pair of 8x42 roof prism binos.  I have 15x70 IF - kind of heavy, really need a tripod, Aculon 10x50s - they're ok but a little hard for me to keep steady, and a pair of 7x50 military surplus porros - built like a tank, less bouncy views, but maybe a little low on the mag.

So what says the collective mind?  Would 8x42s be redundant, considering what I have?  There's a good chance I'd sell off one or more of the others if the 8x42s did the trick.

 

~

Since you don't currently have an 8x42 to use for astro work (for daytime use that size checks many observing boxes) I suggest getting them, by all means. However, I prefer 10x50s at night more often than not, and using them attached to a monopod is a great way to stabilize them.  Monopods collapse quite small and are easily packed away for traveling.

Good luck.

 

 

 

. 

[Captain Scarlet]

Having an exit pupil significantly larger than your eye’s pupil is not necessarily a bad thing. It makes eye placement very comfortable, allowing you a range of movement of your eye whilst still “filling up” your own pupil. I’m told that telescopic sights for rifles often deliberately have excessive exit pupils for just that reason. My own 8x56 pair of binos are very comfortable, though of course somewhat heavy.

On topic, I have a pair of old Leica Trinovid 8x42s and they never cease to elicit amazement when I lend them out.

Magnus

Edited February 26 by Captain Scarlet
typo

[NGC 1502]

9 minutes ago, Captain Scarlet said:

Having an exit pupil significantly larger than your eye’s pupil is not necessarily a bad thing. It makes eye placement very comfortable, allowing you a range of movement of your eye whilst still “filling up” your own pupil.

Definitely agree, this is very often overlooked.

[PeterW]

Using the full 7mm pupil can begin to show worse stars as your eye lens has worse figure for larger pupil diameters. I’d get a trigger grip and monopod like this…

https://binocularsky.com/binoc_mount.php

stabilise the 15x70, to improve the view. As others suggest a lighter 8x would be useful, could also be carried around and used in the daytime.

 

peter

 

[ScouseSpaceCadet]

On 22/02/2024 at 15:03, jjohnson3803 said:

I have a little extra astro money on hand and I'm seriously considering getting a pair of 8x42 roof prism binos.  I have 15x70 IF - kind of heavy, really need a tripod, Aculon 10x50s - they're ok but a little hard for me to keep steady, and a pair of 7x50 military surplus porros - built like a tank, less bouncy views, but maybe a little low on the mag.

So what says the collective mind?  Would 8x42s be redundant, considering what I have?  There's a good chance I'd sell off one or more of the others if the 8x42s did the trick.

 

I bought 8x42s for my dad in his 70s. They actually fine for astronomy (compared to my 10x50s). I can hold them much steadier than the 10x50s. Worth a punt for that reason alone.

[jjohnson3803]

I wound up buying a pair of Vortex Crossfire 8x42s.  I considered Vortex Diamondbacks, but didn't want to spend the extra money in case the 8x42s didn't work out.

The weather has been pretty much rubbish (as expected 🤪), but I've been quite happy with them the few times I've had them out.  I have a trip coming up and hope to see what they can do under darker skies.