Patches on Mak glass

[Matt S]

This is probably nothing to fuss about, but I’ve noticed some patches forming on the front glass of my Mak, it’s only noticeable when it starts to get dewy and I’ve only noticed them when observing and out of focus. 
Really just wondering if it’s something to leave or worth a clean?

 

 

[Nik271]

This is normal it's  how the dew forms on glass which is not 100% clean, the moisture attaches to the (usually invisible) traces of dust, pollen and sediment on the glass. Only worth cleaning if you can see any residue after it dries out. 

[Matt S]

Thanks @Nik271, just what I wanted to hear. I figured it’d be something like that. I can’t really see any residue once it has evaporated, plus a dew shield has helped.