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Message: <blockquote data-quote="Kevin Purcell" data-source="post: 1712507" data-attributes="member: 68323">I think by flat you mean "sharp at the edge". The Zeiss Diascope I've looked through have quite a flat field (i.e. little field curvature) but they do (like other Zeiss optical designs) have a fair amount of astigmatism at the edge (more noticeable at lower magnifications where they have wider FOVs especially with the 65mm).The question is perhaps who are "the others" are. Clearly it doesn't bother current Zeiss owners including me. And others (e.g. Kimmo in this older Alula reviews -- of course it's now 6 or 7 years on).<a href="http://www.lintuvaruste.fi/hinnasto/optiikkaarvostelu/optics_6_SearovskiATS80HD_GB.shtml" target="_blank">http://www.lintuvaruste.fi/hinnasto/optiikkaarvostelu/optics_6_SearovskiATS80HD_GB.shtml</a><a href="http://www.lintuvaruste.fi/hinnasto/optiikkaarvostelu/optics_5_Smallscopes_GB.shtml" target="_blank">http://www.lintuvaruste.fi/hinnasto/optiikkaarvostelu/optics_5_Smallscopes_GB.shtml</a>And for some the price trade off (as these scopes are cheaper than the Kowa, Nikon EDG, Swaro and Leica) is worth it. Each to their own. But perhaps you mean attracting people over from the other Big Scope makers: that may be more of an issue. Different scopes for Different folks but each time I look at the pricing of the others I rather gasp.Perhaps they've improved the edge sharpness (another change in the optical design) or perhaps they're happy with the current design. It's a rather difficult one to bring up in the PR unless you've decided it's a big feature and it's now "sharp from edge to edge". I haven't seen that for the new Diascopes.The other comment I meant to make before was the one about Zeiss switching to porro prism for the image erector. I think with both Zeiss and Leica they believe their roof prism erectors are as good as a porro and this would be an affront to their optical design and implementation skills <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /></blockquote>

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