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More discoveries. NEW: Zeiss Victory SF 32

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Search: Posts Made By: henry link
Forum: Zeiss Tuesday 17th March 2020, 20:00
Replies: 86
Views: 1,963
Posted By henry link
Joker, I notice that the center column is a...

Joker,

I notice that the center column is a little extended in your photo. That should be avoided if possible.

Henry
Forum: Zeiss Tuesday 17th March 2020, 17:21
Replies: 86
Views: 1,963
Posted By henry link
I have one of these old Zeiss zooms. Even when...

I have one of these old Zeiss zooms. Even when the eyepiece is not on a scope I can easily see all sorts of detritus: specks, flecks, fibers and bubbles or droplets at the 20x setting. That's because...
Forum: Meopta Monday 16th March 2020, 17:12
Replies: 36
Views: 2,232
Posted By henry link
My numbers, Jerry, but they come from sources in...

My numbers, Jerry, but they come from sources in the 2019 Meopta catalogue. There's a graph showing the difference between rifle scopes using MeoLux vs MeoBright and in the technical data at the end...
Forum: Meopta Saturday 14th March 2020, 18:22
Replies: 36
Views: 2,232
Posted By henry link
That's a good development. Using the light...

That's a good development. Using the light transmission graphs from the 2018 catalogue I speculated in another thread that the improvement in light transmission from changing to MeoLux should be...
Forum: Zeiss Saturday 14th March 2020, 17:51
Replies: 106
Views: 5,021
Posted By henry link
Hey Bill, I returned the 8x54 HT in those photos...

Hey Bill,

I returned the 8x54 HT in those photos for reasons unrelated to its color bias. The slight green cast in the 8x56 FL is visible if I look for it, but I don't often notice it. I have a...
Forum: Zeiss Friday 13th March 2020, 19:03
Replies: 106
Views: 5,021
Posted By henry link
Making a serviceable photo of the color bias is...

Making a serviceable photo of the color bias is not hard, even with a phone camera. Below I just leaned a white foam board against an outside wall on a cloudy day (just now) and lined up the...
Forum: Zeiss Thursday 12th March 2020, 19:46
Replies: 106
Views: 5,021
Posted By henry link
I just read though page 1 of this old...

I just read though page 1 of this old thread.

https://www.birdforum.net/showthread.php?t=321724

As you can see we've been around this block a few times before. Starting with my post #11 there are a...
Forum: Zeiss Thursday 12th March 2020, 11:59
Replies: 106
Views: 5,021
Posted By henry link
I don't think the idea of the Japanese having a...

I don't think the idea of the Japanese having a cultural preference for a green bias holds up when a wider selection of binoculars is included. Since the introduction of multi-coating Nikon...
Forum: Spotting Scopes & tripod/heads Wednesday 11th March 2020, 16:35
Replies: 16
Views: 716
Posted By henry link
The effect of the Harpia's aperture stop down at...

The effect of the Harpia's aperture stop down at 23x can be easily simulated with any large scope. See below:

https://www.birdforum.net/showpost.php?p=3613587&postcount=125

Instantaneously changing...
Forum: Spotting Scopes & tripod/heads Tuesday 10th March 2020, 13:03
Replies: 16
Views: 716
Posted By henry link
Always keep in mind that these calculations...

Always keep in mind that these calculations depend on the accuracy of the light transmission measurements you are relying on. Old measurements might not represent current production or they may be...
Forum: Binoculars Monday 9th March 2020, 18:13
Replies: 27
Views: 1,812
Posted By henry link
If you haven't seen it this thread deals with the...

If you haven't seen it this thread deals with the subject.

https://www.birdforum.net/showthread.php?t=376722&highlight=relaxed+view

I take a stab at making a list of requirements in post #28.

Henry
Forum: Spotting Scopes & tripod/heads Monday 9th March 2020, 14:52
Replies: 16
Views: 716
Posted By henry link
Binastro is right about apertures not always...

Binastro is right about apertures not always being on spec. I measured 93mm for the Zeiss Harpia's clear aperture and only 80mm for the "85mm" Zeiss Gavia. The Harpia also has the transmission...
Forum: Spotting Scopes & tripod/heads Monday 9th March 2020, 11:32
Replies: 16
Views: 716
Posted By henry link
There's a simple mathematical way to predict how...

There's a simple mathematical way to predict how much higher light transmission is required from a smaller scope to equal the image brightness of a larger one. Square the diameters of the scope...
Forum: Kowa Saturday 7th March 2020, 18:52
Replies: 121
Views: 13,266
Posted By henry link
Thanks Mike. I just noticed that the AFOV of the...

Thanks Mike.

I just noticed that the AFOV of the 6.5x32 should be considerable smaller than the 10x42. I say "should be" because Kowa's spec for the 10x42 was so far off. Anyway, a smaller AFOV...
Forum: Zeiss Saturday 7th March 2020, 18:06
Replies: 404
Views: 39,751
Posted By henry link
Hi Canip, I have three transmission spectra for...

Hi Canip,

I have three transmission spectra for the 8x56 FL on my old computer (Gijs, Allbinos and Zeiss). If my memory is correct they are in decent agreement that its peak transmission is in the...
Forum: Zeiss Saturday 7th March 2020, 15:33
Replies: 404
Views: 39,751
Posted By henry link
A green bias in some (I haven't seen them all)...

A green bias in some (I haven't seen them all) Zeiss binoculars has been evident to me since 2007 when I first bought a Lotutec coated FL. See the post below from...
Forum: Kowa Saturday 7th March 2020, 15:07
Replies: 121
Views: 13,266
Posted By henry link
From the observations and photos posted so far I...

From the observations and photos posted so far I would say the 6.5x32 has the same mustache distortion profile as the 10x42, but the swing between the two rectilinear distortions is less extreme in...
Forum: Zeiss Friday 6th March 2020, 19:36
Replies: 404
Views: 39,751
Posted By henry link
Thanks Robert. I went through an HD version of...

Thanks Robert.

I went through an HD version of the animation, which completely altered my interpretation of the layout. Now I think the objective and focuser resemble some early Swaro SLC designs...
Forum: Zeiss Friday 6th March 2020, 17:48
Replies: 404
Views: 39,751
Posted By henry link
Thanks Lee. I've been going through a low...

Thanks Lee.

I've been going through a low quality exploding animation on You Tube trying to get a better idea of the design. It looks like there's a fixed triplet up front and the focusing lens...
Forum: Zeiss Friday 6th March 2020, 15:10
Replies: 404
Views: 39,751
Posted By henry link
From the internal view below it looks like the...

From the internal view below it looks like the optical design of the 32mm SFs is quite a departure from the 42mm models. There is a new 5 group eyepiece design (6-9 lenses?, cementings are hard to...
Forum: Kowa Friday 6th March 2020, 14:00
Replies: 121
Views: 13,266
Posted By henry link
Thanks Canip, Torview and Mike for your...

Thanks Canip, Torview and Mike for your efforts!

Torview's image does show a more complete view of the mustache distortion pattern, but I'm curious about the prism edges that visibly intrude inside...
Forum: Kowa Thursday 5th March 2020, 14:03
Replies: 121
Views: 13,266
Posted By henry link
Hi Canip, I think the camera was too far from...

Hi Canip,

I think the camera was too far from the front of the binocular. It needs to be close enough so that the camera can see the sharp field stop of the eyepiece. The fuzzy opening in your photo...
Forum: Kowa Wednesday 4th March 2020, 14:05
Replies: 121
Views: 13,266
Posted By henry link
That's very surprising to me, Gijs. As you know...

That's very surprising to me, Gijs. As you know it's impossible for a binocular to have no distortion. The designer has to choose between more pincushion with less angular magnification distortion,...
Forum: Swarovski Tuesday 3rd March 2020, 19:44
Replies: 11
Views: 567
Posted By henry link
I owned most of the SL models between about 1985...

I owned most of the SL models between about 1985 and 1992. They used the 3-layer Swarotop multi-coating of the time. A new one was quite bright and much less yellow biased than the 2-layer "Transmax"...
Forum: Kowa Tuesday 3rd March 2020, 19:21
Replies: 121
Views: 13,266
Posted By henry link
Gijs, I think you will be able to see the...

Gijs,

I think you will be able to see the distortion if you examine a 5 cm circle from about 8 meters away (or any combination of circle size and distance that results in a circle that subtends...
Showing results 1 to 25 of 1000
 


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