Thread: A comparison of HD vs non HD high end scopes

I was fortunate to be able to gather together four high end scopes for comparison in diminishing light conditions.
The target was a cypress tree 200 m distant. The basic foliage was dull green with many shadows between branch tufts, branches, major limbs (grey brown) and small foliage leaflets which could enable an assessment of sharpness of definition.
The test scopes included non HD japanese and german lenses and japanese and leupold HD lenses.
The time period ran from mid afternoon through till dark and the four scopes were aligned and supported side by side.
Initially in good light all four scopes performed well. All were set at 10x magnification.
The differences in target definition between them was of no real effect until sunset about 15 minutes before dark.
As dusk fell (Dark-10 minutes (d- 10)) the non HD scope with 44mm objective had lost ability to discern twigs in shadow amongst the foliage and imo was at its effective limit for hunting.
The other non HD scope with German glass remained equally functional with the two HD scopes.
At D-5 the german non HD scope showed slightly less brightness than the HD scopes and was less sharp in definition but still useable. This scope had a 56mm obj and a handy wider field of view as well.
At approx D-3 the non hd became marginal. At this point the two HD scopes also showed differences in brightness and sharpness and contrast between them.
Things changed rapidly in the last moments a couple of minutes before dark. One of the HD scopes was useable for a minute or so later than the other and the non HD German scope remarkably hung in there with those till the final two minutes.
The best clearest brightest and sharpest was a delta HD. The other HD was a Leupold vx5 HD ZL2 and for this test about 1minute short of the Delta.
The german Docter even though not HD was within seconds of the Leupold in terms of usability and had a wide fov. The latter three scopes all had very good centre dot variable illumination. The Docter was a v6 3-15 *56 with 100cm elevation and 80cm widage and wide fov so impressive for a non hd scope.
The Delta value for money and performance is amazing. With the HD being very good I cannot help but wonder just what their ED lens scopes would perform like.
Well this was only a seat of the pants omparison with old eyeballs but interesting all the same, at least to me, so I thought I would pass on my experieces for what its worth. Cheers.

What size objective was the VX5? And the others for that matter.

Docter 3-15*56.
Delta 4-24 * 50
Leupold 2-10 * 42
Bushy elite tactical 3- 12 *44.
The Delta kindly loaned to me by @Sarvo due to international holdups for two new Delta's I have pre ordered from him. The bushy and leupy are b both mine. I also have a NF 2-10*35 but it is not HD either. The clarity and definition of that delta sarvo loaned me are simply impressive.

Yes. I thought about adjusting mag ra ges to compensate for differences in obj lens size but decided that in a hunting situation one would likely use 10x regardless of the scope in hand; so the test was about practical application rather than pedantics. Ultimaty it came down to which of those scopes would give best view of a deer in near dark. The delta sarvo loaned me was very good. The Docter had a wide field of view and would be perhaps better at relocating target after recoil. Those sorts of pluses and minuses usually come down to individual hunter preferences but for me today the delta ticks the boxes and via sarvo seems to me to be best value for money. Others opinions may differ but I ran the test to answer my own curiosity.

Would be interesting to compare a VX5 3-15x44 to a VX5 3-15x56. Apples with apples so to speak. That would show the difference objective lens size makes to light gathering. Personally those big (50mm+) objectives just don't suit the rifles I use.

Comes down to users practical requirements. I could not even consider the cost of a 56mm HD Leupold and even the vx5 you mention are 2k+; so for performance and value
-- pretty clear to me ay.

"HD" glass means High Density glass. Wikipedia says this: "The density of soda glass is 2.4 g/cm3 (39 g/cu in) or below, while typical lead crystal has a density of around 3.1 g/cm3 (51 g/in3) and high-lead glass can be over 4.0 g/cm3 (66 g/in3) or even up to 5.9 g/cm3 (97 g/in3)."

Why use higher density glass? you get better refractive index - which leads to probably sharper image and less CA.

But, it is should not provide better light transmission, which seems to be what you were measuring.

What affects amount of light transmitted are:
1. objective size divided by focal length (also known as magnification)
2. number of glass used. each additional glass will cut light transmission by some degree. more more glass means more/better correction and also more complex design to accommodate more adjustment range.
3. quality of coating.

Generally speaking if you have all scopes set at the same focal length, the scope with largest objective length should pass the most amount of light. But design and coating also affects this.

Perhaps; but i tested and reported on what scopes I had in hand and what I observed as if hunting. End of story. The results satisfied my curiosity and also vindicate my purchasing decision.
One of the delta I have coming from @Sarvo has a 56mm obj and HD. I am looking forward to that !

HD is pretty much a marketing term used these days to suck in buyers.
No point comparing scopes of different magnifications and objective sizes.
Lense coatings play a huge part in various optical qualities.
And please - tube diameter myth has ..no .. relevance.. on ..optical ..performance

Originally Posted by 55six

HD is pretty much a marketing term used these days to suck in buyers.
No point comparing scopes of different magnifications and objective sizes.
Lense coatings play a huge part in various optical qualities.
And please - tube diameter myth has ..no .. relevance.. on ..optical ..performance

This.

FFS! I did not mention tube diameter, lens coatings etc; only comparing sight picture in fading light with scoped all on 10 x.
Nit pickers.

Originally Posted by Tahr

This.

Mimms2 did (tube diameter) and its a theme that keeps reoccurring and that is incorrect.

Your test was great and I enjoyed reading it.
Ya touchy old bugga.

I BELIEVE the old old old rule of devide front lens size by magnification and anything more than 7 is wasted,any less than 7 is less than ideal...the human eye can take 7
why the 6x42mm 4x32mm just WORK.... the balance is there....next time you in that twilight zone,try dropping magnification till you hit that number,its surprising what a difference it makes...I shot two hares right on dark a couple of months back..the leupold scope is a 4.5x15x44 I THINK.....and 6 power worked ok,and more and it was too dark...I shot first hare at 150ish,tracked 2nd hare in scope,couldnt see with naked eye,it stopped at 225ish,could JUST make out darker spot in grass,squeazed off 22-250 with 50grn vmax and was rewarded by vapour cloud and fur,seen at shot impact....my 223 with its 3x9x50mm is very good in poor light BUT the old nikko stirling 3x9x40mm that finnwolf now has beat them all hands down and has better field of view too....

Originally Posted by Woody

FFS! I did not mention tube diameter, lens coatings etc; only comparing sight picture in fading light with scoped all on 10 x.
Nit pickers.

What you saw is what we got, can't ask for more. Lucky you weren't comparing EV's, the jury would be out for a week.

When I was meat hunting I mainly used a 7*61 and had a leupold fixed 4*32 on it. Never failed me and just used holdover. Eyes were younger then.