Used Nikon lens fungus and/or scratches

[Seoras]

I’ve been looking online for a cheap lens for my cheap Nikon D3100, don’t want to spend too much as the camera was only £69. Some of the adverts say there is ‘some fungus inside’ or ’light scratches on the lens’. Should I be avoiding these at all costs or is it possible that these issues won’t affect the images as the sellers are saying? Also, is there a particular lens for this camera that would be more suited to astrophotography? As I’m a complete beginner I’m not looking for perfection, just the chance to practice taking photos before I buy something better,

many thanks, Geo

[happy-kat]

Unless you are going to strip the lens I wouldn't get a fungus one. I've no idea about Nikon lenses. Scratches perhaps depends how deep they are as to whether they might cause a defraction spike on really bright objects. M42 fit lenses are no good on a nikon wrong distance for focus/infinity unlike they do work with canon.

 

[Louis D]

Avoid fungus.  It can spread to other optics once in your home.  The problem only gets worse as the fungus spreads within the lens.

Minor scratches at the edge might not affect the image.  Avoid them across the center.  Avoid the lens if it looks to have been sandblasted (used near beaches, waterfalls, etc.).

A basic, manual 50mm f/1.4 to f/1.8 lens from years ago can be a good starting point for very little outlay.  Autofocus doesn't buy you much if anything in astrophotography.

[Seoras]

No fungus for me then, glad I asked 😊. I’ll start looking for a manual 50mm and see what’s out there, as always, really grateful for your advice 👍