Zeiss Colour Cast (1 Viewer)

rogerscoth · Mar 24, 2004

scampo said:
I think you are right - scope manufacturers have to compromise in many areas and some choose a certain colour cast for various reasons. A slight yellow will be better in certain conditions, a slight blue in others.
I am sure we get used to whatever we have - in fact, I know we do - it is a vital aspect of the brain's function.

Not wishing to increase your blood pressure again Steve, but to quote from the magazine in your waste paper bin :-"But even with the optical image, you will have a personal preference. Most optics have some form of slight colour cast.These are intentionally introduced by the manufacturer to enhance different aspects of the individual model's optical performance."
Personally, (don't laugh everybody!) I have a "lazy" left eye since childhood days, therefore always use my right eye for 'scoping (or should that be coping?) and always keep my left open. Oh, and thanks for assuming I have a brain

Roger

scampo · Mar 24, 2004

A brain, Roger? Did I assume that? Whoa! Must stop making these unsupported assumptions about folk I don't know...

(-;

(if it sounded condescending, btw, sorry! It wasn't meant to be - maybe my teacher side crept out unconsciously...).

And well, yes, I fully agree with your comments regarding the magazine review but, confusingly, what was printed in the general intro was not quite what was written in the specific detail under each scope. Similarly, the sub-headings for some of the individual scope entries hardly equated with the content of the reviews.

Talking about eyes, I discovered today that my left eye (not the one I usually use) seems to give a brighter image than my right eye!

gorank · Mar 27, 2004

If you havent already seen this scope test, check out the transmission diagrams on the last pages. Says a lot about the "color casts" on different scopes..

http://www.vogelbescherming.nl/documents/Telescoop test 2003.pdf

I think its mostly about optical design decisions...a yellow "cast" tends to increase contrast which is preferred by many people...others like a more neutral image...with a little less contrast...is it possible to have both?? well...ask a Nikon-birder...;-)

Swissboy · Mar 27, 2004

gorank said:
If you havent already seen this scope test, check out the transmission diagrams on the last pages. Says a lot about the "color casts" on different scopes..

http://www.vogelbescherming.nl/documents/Telescoop test 2003.pdf

I think its mostly about optical design decisions...a yellow "cast" tends to increase contrast which is preferred by many people...others like a more neutral image...with a little less contrast...is it possible to have both?? well...ask a Nikon-birder...;-)

GREAT, gorank, thanks for that link. Too bad they did not also include the Nikon scopes. Now, if only my Dutch were a bit better, I assume the texts will be interesting as well.

scampo · Mar 27, 2004

It translates quite well, Robert, online.

Swissboy · Mar 27, 2004

scampo said:
It translates quite well, Robert, online.

How do I do it with a PDF file?

scampo · Mar 27, 2004

There's an online translator that allows cut and paste. I searched on Google - it's run by a private company but the online translator is free.

Swissboy · Mar 28, 2004

scampo said:
There's an online translator that allows cut and paste. I searched on Google - it's run by a private company but the online translator is free.

Thanks, Steve, there are not that many that do translations from Dutch. I tried World Lingo. With moderate results. There are rather basic words that its machine does not seem to know. Any better suggestions?

I know, this seems OT at first. But it helps us all to get to that original text which is certainly part of the topic. Robert (Swissboy)

scampo · Mar 28, 2004

No - the one I used even had an "optics/photography" selection to improve translation - but to no avail. I managed enough to make sense of it. What intrigued me was how they commented on the high brightness of the new Zeiss 85T* compared with all other scopes - quite the reverse of a recent UK magazine review.

hinnark · Jul 11, 2004

gorank said:
If you havent already seen this scope test, check out the transmission diagrams on the last pages. Says a lot about the "color casts" on different scopes..

http://www.vogelbescherming.nl/documents/Telescoop test 2003.pdf

I think its mostly about optical design decisions...a yellow "cast" tends to increase contrast which is preferred by many people...others like a more neutral image...with a little less contrast...is it possible to have both?? well...ask a Nikon-birder...;-)

Hi Gorank,

to make it more clear: the yellow cast is a result of optimation of lens and prism coatings for twighlight viewing in the dawn or at night. In the dark only black-white receptors are working in our eyes. They are most sensible for a light going to bluish. Yellow cast is heightening this kind of contrast. Zeiss has concentrated on this effect with their Victory binos and also with their Diascope scopes. I think they believed to sell most optics for hunters who need this characteristics.

Steve

galt_57 · Jul 11, 2004

hinnark said:
...to make it more clear: the yellow cast is a result of optimation of lens and prism coatings for twighlight viewing in the dawn or at night.[...]

I don't see it. I suppose some people are more sensitive to noticing this sort of thing. Either that or there is a variation among scopes.

Hermann · Jul 11, 2004

galt_57 said:
I don't see it. I suppose some people are more sensitive to noticing this sort of thing. Either that or there is a variation among scopes.

Chances are you don't see it. Colour casts are IME perhaps the most subjective factor of all when it comes to optics. Alright, there are some rather clearcut cases, such as the *very* obvious yellow colour of some military binoculars or of the early Swarovski bins, but whether you "see" a colour cast or not seems to depend to a large extent on your own perception.

BTW, to my eyes the Nikon EDII and EDIII are slightly redish, the Leica Apo ist yellowish-warm, the Swarovski 65HD is close to neutral, the Zeiss is also close to neutral, perhaps a bit bluish.

Hermann

hinnark · Jul 12, 2004

Hermann said:
BTW, to my eyes the Nikon EDII and EDIII are slightly redish, the Leica Apo ist yellowish-warm, the Swarovski 65HD is close to neutral, the Zeiss is also close to neutral, perhaps a bit bluish.

Hermann

The bias is visible best if you compare the scopes side by side. Doing this I found that Kowa TSN-823M Prominar tends to bluish, Leica Apo Televid 77 and Swarovski ATS HD 80 are neutral and the Zeiss 85 Diascope which I own has a slightly warm (yellow green) bias. Nikon ED 78 seemed also like their bino HG series redish to my eyes. Note: this has nothing to do with their optical quality or assessment so I would say that bias is the better word. Only for digiscoping the neutral scopes perform best IMO. It seems to me that the bias shows often the complementary color of the respective coatings that has been used by the manufacturers which is visible on ocular and frontlenses when you watch and turning the bino or scope slowly under daylight. When you doing this you maybe notice different coloring of the 2, 3 or even 4 lenses in the front. Coating is a very complex thing so let us now doing it not too complicated. The reason for this may be this. The color of the coatings is just the part of visible spectrum that is reflecting by the lenses and that is not passing by as easy as other color or wave lengths of light. So other colors wil be pass by and their summation will generate what we call bias when we are looking through the scope.

Steve

Zeiss Colour Cast (1 Viewer)

More options

rogerscoth

Well-known member

scampo

Steve Campsall

gorank

Well-known member

Swissboy

Sempach, Switzerland

scampo

Steve Campsall

Swissboy

Sempach, Switzerland

scampo

Steve Campsall

Swissboy

Sempach, Switzerland

scampo

Steve Campsall

hinnark

Well-known member

galt_57

Dave - Zeiss-85, CP990

Hermann

Well-known member

hinnark

Well-known member

Similar threads

Users who are viewing this thread