7x50 binos?

[Alfian]

I'm fortunate to have the opportunity to spend time in a dark sky location and although I have useful collection of binoculars I keep running over the idea of getting some 7x50s. There is the logical (sensible?) part of me that says given my age and diminishing pupil limitations that an 8x42/3 would make much more sense. In short I am looking for good light grasp bino with good optics, but hand holdable for older hands. I'm wondering whether in practice any fellow stargazers of 65+ age find any advantage in using 7x50s. I'll confess to being drawn to the Opticron Marine 3 BIF GA 7x50s at FLO although I am open to other suggestions up to £200 and not too heavy.

[Charic]

This is what I use and favour. https://www.firstlightoptics.com/all-binoculars/helios-naturesport-plus-8x40-wa-binoculars.html

Your dilated and age related eyes may not allow you to get the full use/benefit of a 7mm exit pupil from the 7x50 option. None of your present binoculars provide  you more than a 5 mm exit pupil, so a 7mm exit from 7x50, will bring no real benefit.

I still have some 7x50's but the 8x40s get used all the time, day and night, and with a good field of view of +8° .

Totally hand holdable at this magnification, even better mounted. Everyone has some hand shake, but mounting a binocular is going to improve what you observe due to the static image.

I also use a sturdy tripod and trigger grip giving me plenty of orientation. 
My Helios Naturesport 8x40's were cheaper ( FLO sale) but still worth  the £69 their charging today. Try them, return them if they don't suit!

I note you have Helios 15x70. I'm assuming Apollo's? I had some for a night, but if I go down that route again, I'm aiming for the Oberwerk Ultra (same optics).

My 8x40's get most use, and my 10x50 Strathspey's are buried in a secure case in the boot of the car if I chance upon something when out driving.  

[BinocularSky]

Measure your pupils, then you'll know whether it's worth going to (Mag)x50. Simple method: http://binocularsky.com/binoc_basics.php#2

[Alfian]

4 hours ago, Charic said:

This is what I use and favour. https://www.firstlightoptics.com/all-binoculars/helios-naturesport-plus-8x40-wa-binoculars.html

Your dilated and age related eyes may not allow you to get the full use/benefit of a 7mm exit pupil from the 7x50 option. None of your present binoculars provide  you more than a 5 mm exit pupil, so a 7mm exit from 7x50, will bring no real benefit.

I still have some 7x50's but the 8x40s get used all the time, day and night, and with a good field of view of +8° .

Totally hand holdable at this magnification, even better mounted. Everyone has some hand shake, but mounting a binocular is going to improve what you observe due to the static image.

I also use a sturdy tripod and trigger grip giving me plenty of orientation. 
My Helios Naturesport 8x40's were cheaper ( FLO sale) but still worth  the £69 their charging today. Try them, return them if they don't suit!

I note you have Helios 15x70. I'm assuming Apollo's? I had some for a night, but if I go down that route again, I'm aiming for the Oberwerk Ultra (same optics).

My 8x40's get most use, and my 10x50 Strathspey's are buried in a secure case in the boot of the car if I chance upon something when out driving.  

My Helios binos are the quantum 4s, a very good 2nd hand buy. They were much better than expected. Interesting that the 8x40s are used over the Strathspeys as I understand the latter are nearer 40mm than 50mm. My Opticron 10x42s are very good but not as "bright" as I am hankering for. Maybe that difference in exit pupil is the key. Maybe its my eyes! The WO 10x50 EDs (ba8) I had were superb but heavy and the eye relief was insufficient. Perhaps a pair of 8x40-42 (ed?) would be good.

 

[Alfian]

4 hours ago, BinocularSky said:

Measure your pupils, then you'll know whether it's worth going to (Mag)x50. Simple method: http://binocularsky.com/binoc_basics.php#2

Thanks Steve, yes thats a very sensible idea. I've never properly measured my EP so I'll give it a go.

[djpaul]

I have recently purchased a pair of Hawke 8x43 frontiers and find them perfect for star hopping. 

I find them very well made . light enough and very comfortable on the eye. 

Most retailers are selling these particular binos for approx £240. 

[Alfian]

On 17/10/2018 at 23:49, djpaul said:

I have recently purchased a pair of Hawke 8x43 frontiers and find them perfect for star hopping. 

I find them very well made . light enough and very comfortable on the eye. 

Most retailers are selling these particular binos for approx £240. 

thanks for that recommendation. There is quite number of 8x42 binos on the market and I feel to have window shopped on the net through all of them. The Frontier ED looks good but in the Hawke range I think the Endurance is nearer my budget. Harking back to my Williams Optics binos, they had something of a wow factor every time I used them so, although my various binos are pretty good, its maybe that that I'm looking for and no doubt that will cost.

I've measured my exit pupil (edit -dilated pupil) as well as I can and to my surprise its 5.5 -5.7 so I know where I'm at with it. In theory therefore a 7x will result in a 40mm max aperture. 

[PeterW]

I’d go formapparent field of view and not she sharpness over raw exit pupil. Many 7x50 have a narrow field of view, which can feel restrictive compared to a wide field of tiny stellar points. 

PEter

[BinocularSky]

On 18/10/2018 at 13:37, Alfian said:

I've measured my exit pupil...

ITYM "entry pupil"? ?

[Charic]

On a side note Steve, given the amount of binoculars you have discovered that are internally stopped down? I would assume, for example, that the full 7.14... exit is not always achievable from a full 7x50 binocular.

Therefore  one would need to know the true aperture to get a more accurate measurement of the exit pupil  

Folk could use the torch method you have often described, taking the size of the exit pupil multiplied by the magnification to ascertain the true aperture of their binoculars. 

I know folk have questioned this in the past, but manufacturers can still have 7x50 on the body because it really is 7x and 50mm, but what happens inside remains a mystery, until you dig deeper, as shown quite often in your reports. 

[Alfian]

3 hours ago, BinocularSky said:

ITYM "entry pupil"? ?

Ahem oops er ...yes.

[Alfian]

On 19/10/2018 at 00:43, PeterW said:

I’d go formapparent field of view and not she sharpness over raw exit pupil. Many 7x50 have a narrow field of view, which can feel restrictive compared to a wide field of tiny stellar points. 

PEter

Apologies for tardy response Peter. Although I like wide field views I would prefer a narrower afov if that gives good  sharpness across much of the fov. It costs more to produce a good wide fov EP than something like a 52 degree one so it a lot to expect at a modest price point that a wide afov bino field sharpness isn't going to fall of the cliff. You gets what you pay for ! That said, to pick up on your point, tunnel vision isn't much fun either especially on a low power bino. My Pentax 20x60 has a 2.2 degree fov (a 44 degree afov) but they are a binoculars that has a particular niche use so imo the end justifies the means. I had looked at the Opticron SR GA 8.5x50 which looks a good binoculars but has an afov of only 42.5 degrees. Sadly no. Current thinking is the Hawke Frontier 8x43 if I can push the budget or possibly the Celestron Trailseeker 8x42 which although not "ED" seems to have some impressive endorsements. interestingly both have a wide fov anyway! We will see.

[BinocularSky]

5 hours ago, Charic said:

On a side note Steve, given the amount of binoculars you have discovered that are internally stopped down? I would assume, for example, that the full 7.14... exit is not always achievable from a full 7x50 binocular.

I've never had my grubbies on a stopped down 7x50, but I'm sure they must exist. Almost all the severely stopped down cases I've seen have been 10x50, Nx60 and Nx70. I do know that some Nx80 and Nx90 are afflicted as well.

More importantly, I think, in this regard, I've not seen many stopped down Nx40 or Nx42 either.

[Charic]

5 hours ago, BinocularSky said:

I've never had my grubbies on a stopped down 7x50

Sorry, my bad!

I actually chose 7x50 to stay in-line with the title theme.

My 15x70 Revelations would have been more appropriate!