• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Crystalline clarity of the HT ? (1 Viewer)

henry link said:
I don't think I had anything very bad to say about the optics of the 8x42 HT. The optical design looks to be essentially the same as the FL, but with improved light transmission, color accuracy and glare resistance.

The problem for me with applying an ultimate superlative like "crystalline clarity" to the HTs or 8x30 Habicht is that it seems to suggest an image, at least in the center of the field, that can't be improved upon. How can binoculars with axial aberrations high enough to visibly affect sharpness (even in a small way) be called "crystal clear"?
Click to expand...

Hi Henry

First off, you are dead right that HT is an FL but improved in the characteristics you mention.

With regard to the term 'crystal clear' and how it can be used for bins with less than perfect sharpness, well, it all depends what is meant by crystal clear. I suggest that some people, some of the time, are using the term crystal clear to describe a transparency of view. Remember the old hifi phrase 'it was as if a veil had been lifted and I felt closer to the music'. I am guessing that this feeling of having a slight but noticeable impediment to seeing the view removed is behind 'crystal clear' and has little to do with ultimate sharpness.

Whle I am at it I will come off the fence regarding 8x42 HT vs SF, having had them both long enough and in different conditions to feel able to state that to my eyes, HT has the most brilliant, transparent and, yes, sparkling view. It also has a sweet spot quite big enough for me, but undeniably that of SF is bigger and the SF's FOV is just huge, and it doesn't lag far behind in the brilliance stakes either. In terms of usuability and enjoyment it is hard to put one in front of the other, but they are different.

Lee
 
I don't know how CA sensitive you are, but how do the SF and HT compare in that regard, in your opinion ? Also, on the 10X42 HT, is there enough eye relief to easily see the full FOV while wearing glasses ?

Thanks
Robert


Troubador said:
Hi Henry

First off, you are dead right that HT is an FL but improved in the characteristics you mention.

With regard to the term 'crystal clear' and how it can be used for bins with less than perfect sharpness, well, it all depends what is meant by crystal clear. I suggest that some people, some of the time, are using the term crystal clear to describe a transparency of view. Remember the old hifi phrase 'it was as if a veil had been lifted and I felt closer to the music'. I am guessing that this feeling of having a slight but noticeable impediment to seeing the view removed is behind 'crystal clear' and has little to do with ultimate sharpness.

Whle I am at it I will come off the fence regarding 8x42 HT vs SF, having had them both long enough and in different conditions to feel able to state that to my eyes, HT has the most brilliant, transparent and, yes, sparkling view. It also has a sweet spot quite big enough for me, but undeniably that of SF is bigger and the SF's FOV is just huge, and it doesn't lag far behind in the brilliance stakes either. In terms of usuability and enjoyment it is hard to put one in front of the other, but they are different.

Lee
Click to expand...
 
Last edited:
So the optics of the HT series, outside of minor nitpicking, are basically superb ?

henry link said:
I don't think I had anything very bad to say about the optics of the 8x42 HT. The optical design looks to be essentially the same as the 8x42 FL, but with improved light transmission, color accuracy and glare resistance.

The problem for me with applying an ultimate superlative like "crystalline clarity" to the HTs or 8x30 Habicht is that it seems to suggest an image, at least in the center of the field, that can't be improved upon. How can binoculars with axial aberrations high enough to visibly affect sharpness (even in a small way) be reasonably called "crystal clear"?
Click to expand...
 
Last edited:
SuperDuty said:
I don't know how CA sensitive you are, but how do the SF and HT compare in that regard, in your opinion ? Also, on the 10X42 HT, is there enough eye relief to easily see the full FOV while wearing glasses ?

Thanks
Robert
Click to expand...

The eyeglasses part I can answer... YES...I use my 10X42HT with eyeglasses all the time. IMO Zeiss tends to be conservative with this measurement. I can use my 8X32 T* FLs with eyeglasses TOO. My HT is listed with a eye relief of 16mm and the T* FL at 15.5 I believe. YMMV.
 
SuperDuty said:
So the optics of the HT series, outside of minor nitpicking, are basically superb ?
Click to expand...

In my personal hierarchy of superlatives the 8x42 HT's optics would get an overall "very good+". I'd like to see lower axial and off-axis aberrations and more linear light transmission, since I know those things can be done better. The 8x54 image isn't that good. I was ready to buy that one to replace my 8x56 FL, but quickly changed my mind when I saw it.

I think I'll wait for something that puts it all together before I haul out "superb" or "crystal clear". ;)
 
I have observed delicate noctilucent clouds since the late 1960s, and try to continue to spot them in summer.
They are in the north and my horizon is roofs at 6 to 8 degree elevation.
I need to observe from this horizon upwards, and the NLCs appear to drift with time depending on the solar angle.
Normally they are seen with the Sun 6 to 16 degrees below the horizon. They are 82km high and can be hundreds of kms away, possibly over Scotland from southern England. Binoculars can show exquisite detail. They change form slowly with time.
They are dependent on the 11 year solar cycle and are also thought to be changing with climate change.

Unfortunately there is a street light just below these north facing roofs. The street light has a rear shield but the side light causes ghosting.
Some NLCs are only spotted with binoculars. They can be faint, elusive and the observations are difficult.
Contrails and cirrus can mimic them from towns.

I have had to abandon using the 1987 HR/5 for this work, which has scientific value. I cannot be hampered by poor binoculars. The HR/5 is very good mostly, but in this context 5 out of 10. Inadequate and not usable. 8.26 deg field.

8x30 EII, c.2005. I thought would work but marginal 6.5/10. 8.85 degrees.
10x35 EII, 2006, also marginal 6.5/10. 7.0 degrees.

10x30 Canon IS II 7.0/10 usable but I need better. 2016. 6.0 degrees, rather small field.

However the Conquest 10x42 HD is superb. 8.5/10. Very little ghosting. 6.65 degrees.

I don't know how the top Swaro/Zeiss/Leica would perform. I suspect the Leica would do well.

I understand that these observations are very specialised.
All the binoculars tested are very good in their own way, but only the Conquest 10x42 HD is up to the job so far. All the binoculars are as new or close to as new.
I would prefer an 8 deg plus field, but have to make do with 6.65 degrees. Perhaps the Conquest 8x32 HD would work well for the NLCs.
The four Porroprism binoculars are inadequate in this context.
 
Last edited:
SuperDuty said:
I don't know how CA sensitive you are, but how do the SF and HT compare in that regard, in your opinion ? Also, on the 10X42 HT, is there enough eye relief to easily see the full FOV while wearing glasses ?

Thanks
Robert
Click to expand...

Hi Rob

I am not too sensitive to CA and don't see it with the HT or SF, and can't comment on 10x42 HT as mine is an 8x. Sorry.

Lee
 
Without reopening a can of worms that has long since been picked clean and discarded in the rubbish bin.....I do my own version of resolution / sharpness testing, mostly in line with what I need my binoculars to do in the field - all manner of bird surveys, butterfly and dragonfly surveys etc.

I have good reference binoculars for comparison - many BGAT/P's, FL, HT, Conquest HD. My HT is sharper [can resolve smaller and finer details] than any of the others I have tried - this includes direct testing in a fixed position with various sizes of print. Informally, I perceive greater sharpness from the HT than what I get from an SV - some of this might be transmission and contrast though.

Some of my best field tests [not bench tests] involve insects. Looking for wing scales on butterflies or wing veins and clasper / cerci shapes is extremely demanding in terms of resolving minute details. I know this isn't the same thing as boosted testing but it's what tells me just how sharp an image my binocular forms.

For birds, my tests would be - just how well does the shape of a bird hold-up at distance? Like a Turkey Vulture vs. Eagle sp. at 5 km or trying to ID swallow species at the visual limit, where you need body / tail shape to stand up over distance. Completely unscientific but it's what I need my binoculars to do. With very little effort, I can tell if a binocular can keep the splayed primaries of a raptor crisp, well-resolved and separated - many cannot at any reasonable distance.

Maybe it comes down to my 'average'-level unaided vision, but [to me] the HT is perfectly sharp - that might change with a better reference for comparison but, so far, I haven't found it - and, no, I have not compared the HT to the 8x56 FL either....
It shouldn't be ignored that Tobias thought the HT to be the sharpest compared to the other alphas, tripod mounted. It may just be that none match up to the 8x56 FL
 
Last edited:
That's good to know Chuck.

chill6x6 said:
The eyeglasses part I can answer... YES...I use my 10X42HT with eyeglasses all the time. IMO Zeiss tends to be conservative with this measurement. I can use my 8X32 T* FLs with eyeglasses TOO. My HT is listed with a eye relief of 16mm and the T* FL at 15.5 I believe. YMMV.
Click to expand...
 
Very informative.


james holdsworth said:
Without reopening a can of worms that has long since been picked clean and discarded in the rubbish bin.....I do my own version of resolution / sharpness testing, mostly in line with what I need my binoculars to do in the field - all manner of bird surveys, butterfly and dragonfly surveys etc.

I have good reference binoculars for comparison - many BGAT/P's, FL, HT, Conquest HD. My HT is sharper [can resolve smaller and finer details] than any of the others I have tried - this includes direct testing in a fixed position with various sizes of print. Informally, I perceive greater sharpness from the HT than what I get from an SV - some of this might be transmission and contrast though.

Some of my best field tests [not bench tests] involve insects. Looking for wing scales on butterflies or wing veins and clasper / cerci shapes is extremely demanding in terms of resolving minute details. I know this isn't the same thing as boosted testing but it's what tells me just how sharp an image my binocular forms.

For birds, my tests would be - just how well does the shape of a bird hold-up at distance? Like a Turkey Vulture vs. Eagle sp. at 5 km or trying to ID swallow species at the visual limit, where you need body / tail shape to stand up over distance. Completely unscientific but it's what I need my binoculars to do. With very little effort, I can tell if a binocular can keep the splayed primaries of a raptor crisp, well-resolved and separated - many cannot at any reasonable distance.

Maybe it comes down to my 'average'-level unaided vision, but [to me] the HT is perfectly sharp - that might change with a better reference for comparison but, so far, I haven't found it - and, no, I have not compared the HT to the 8x56 FL either....
It shouldn't be ignored that Tobias thought the HT to be the sharpest compared to the other alphas, tripod mounted. It may just be that none match up to the 8x56 FL
Click to expand...
 
james holdsworth said:
Without reopening a can of worms that has long since been picked clean and discarded in the rubbish bin.....I do my own version of resolution / sharpness testing, mostly in line with what I need my binoculars to do in the field - all manner of bird surveys, butterfly and dragonfly surveys etc.

I have good reference binoculars for comparison - many BGAT/P's, FL, HT, Conquest HD. My HT is sharper [can resolve smaller and finer details] than any of the others I have tried - this includes direct testing in a fixed position with various sizes of print. Informally, I perceive greater sharpness from the HT than what I get from an SV - some of this might be transmission and contrast though.

Some of my best field tests [not bench tests] involve insects. Looking for wing scales on butterflies or wing veins and clasper / cerci shapes is extremely demanding in terms of resolving minute details. I know this isn't the same thing as boosted testing but it's what tells me just how sharp an image my binocular forms.

For birds, my tests would be - just how well does the shape of a bird hold-up at distance? Like a Turkey Vulture vs. Eagle sp. at 5 km or trying to ID swallow species at the visual limit, where you need body / tail shape to stand up over distance. Completely unscientific but it's what I need my binoculars to do. With very little effort, I can tell if a binocular can keep the splayed primaries of a raptor crisp, well-resolved and separated - many cannot at any reasonable distance.

Maybe it comes down to my 'average'-level unaided vision, but [to me] the HT is perfectly sharp - that might change with a better reference for comparison but, so far, I haven't found it - and, no, I have not compared the HT to the 8x56 FL either....
It shouldn't be ignored that Tobias thought the HT to be the sharpest compared to the other alphas, tripod mounted. It may just be that none match up to the 8x56 FL
Click to expand...

Have you considered hand shake as a factor?

While there are exceptions, the effective resolution of most modern binoculars is actually pretty good and in practice eyesight will be limiting even for those with 20/10 vision. Using 6 of my binoculars I worked out the test chart limit of what I could see tripod mounted and hand held. The difference ranged between 25% and 45% worse hand held. For the 45 percenters I could improve the performance by adding weight at some point along the length of the binocular to change the balance. I don't know if this would translate to other users at all but for me weight and balance make around a 20% difference to the level of detail I can see.

Tobias, as a professional photographer is very aware of perceptual sharpness differences between lenses. This is a totally different parameter from acuity or effective resolution limits and while there are 'sharpness' differences between binoculars in my experience is very dependant on the illuminating light unlike resolution. While I had the Kite Bonelli 2.0 for review I was able to compare it to compare it to a Zeiss FL and a HT briefly, amongst many others. Under the light conditions at the time the Kite was clearly 'sharper' than the Zeiss pair (and others I tried) but I could see no difference at all in limiting detail as I would expect. The tables may well have turned in different light, I couldn't say. I've seen no eveidence that perceived sharpness is an intentional part of binocular design, but I could be wrong.

It's not something I've been been able to pin down by testing but I suspect perceived shapness is unaffected by hand shake, unlike limiting resolution.

David
 
james holdsworth said:
I think terms like sparkle, dynamic, lively etc. are [surely] subjective terms but also capture something that dry, technical terms cannot.
Click to expand...
Honestly, the buzzwords (e.g. sparkle, brilliance, etc.) are perfectly fine in individual reviews; however, because they are not even remotely quantifiable (e.g. looking at the transmission tests of the Leica HD+ shows that the so-called "high-transmission sparkle" is quite obviously not a byproduct of high transmission), I do not think they should be discussed when comparing different binoculars. I guess that is just the scientist in me, though.

J
 
In my experience the detection of unknown detail using either tripod mounted or IS binoculars is equivalent to a 100% increase in resolution not 25% to 45%.

This is for two reasons.

Firstly, you are not looking at a known object like a test chart.
But something completely unknown.

Secondly, you are seeing something constantly still, instead of glimpses lasting fractions of a second.

Once you know the hidden object is there then the effective resolution is more like using a test chart.

Hidden detail has been revealed to me repeatedly using IS binoculars, which is quite invisible and not suspected just hand held.

This concentration on test charts as an accurate tool in the detection of unknown detail is in my opinion flawed.
 
Reading unknown newspapers is better, but it won't reveal a deliberately false letter within the text. You can also guess a word from context. You may be wrong.
You might see it with a tripod mounted or IS binocular but not with a handheld binocular.

By its nature hidden detail may be completely foreign to what you are looking at or looking for.

Discoveries are made when totally unconnected strange things are seen.

You know that a standard newspaper text contains letters. So this is not an adequate test for unknown detail.

In fact there isn't a test for unknown detail. It is unknown.
It is only through long term experience one can say how much hidden detail turns up during observations.
This is not science, it is experience of what happens in the world we are in.
 
I basically just let my eyes tell me, if something pleases me personally that's what I'm looking for regardless of how it checks out technically.
 
Warning! This thread is more than 8 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Similar threads

etc
New Leica Ultravid HD Plus 12x50 - compared with Swarovski EL 12x50 and Zeiss 10x54 HT
2
Replies
30
Views
5K
ReinierB
R
H
Yawn, just another SFL 40 comparison...
Replies
13
Views
3K
Romão Gomes
R
etc
Zeiss 10x54 HT and 8x42 SF - an informal review and first impressions
Replies
12
Views
4K
etc
etc
hopster
Optical comparison of Habicht 10x40 and HT (or FL) 10x42
2
Replies
34
Views
3K
hopster
hopster
C
The Zeiss SFL 8x30 compared with select current 8x30/8x32 roof binoculars
15 16 17
Replies
324
Views
54K
Maljunulo
M

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)
Back
Top