Hermann
Well-known member
Most of your points are valid, but Holger's review is not. The Dailyt he reviewed did not have the T* multi-coatings or phase coating. Both of these put the newer ones into a much higher performance level. And, he himself, mentions that there could be a problem with the mirror coatings... Also, I have always found the Dailyt's to preform very well in back-lit situations.
I did a pretty thorough comparison in the field years ago between my own Zeiss 10x40BGA (no muli-coating, no phase coating), a Zeiss 10x40BGAT* (multi-coating, no phase-coating) and a Zeiss 10x40BGAT*P (multi-coating and phase-coating).
The differences between these three versions of the Dialyt were rather clear-cut and somewhat larger than I thought they would be, with the latest version quite clearly better than the two earlier versions, both with regard to contrast and to resolution. My own 10x40BGA, dating back to 1979, looked rather dull with washed out colours when compared to the 10x40BGAT*P in particular. The difference between the 10x40BGA and the 10x40BGAT* (without phase coating) was still obvious, but my conclusion at the time was that the phase coating made a larger difference than the multi-coating.
Interestingly a Zeiss West 10x50 Porro from 1961 (with single layer coatings) beat both 10x40s without phase coating quite easily with much better resolution and still had the edge over the 10x40BGAT*P. The contrast wasn't as good as in the multi-coated Dialyts, but the resolution was still slightly better than that of the 10x40BGAT*P with a visibly sharper image.
Hermann