Best lens to use for comet ison with nikon d5100?

[CC Bear (Tim)]

Hi all

Just getting into astrophotography and have the kit lenses 18-55 and 55-300mm.

Am looking at a prime lens if this will get me a significantly superior shot of the comet later this year....my budget can stretch to about $220, so as the d5100 is apparently not suited to the 50mm 1.8d, am looking at the 35/50/85mm 1.8g range.

Appreciate advice as to which would be best for the comet, and which best for general astrophotography....this lens will be used almost exclusively for astrophotography...I've taken shots of plaeides, Orion Nebula so far at around 100mm with the kit 55-300 zoom, and carina star field shots at around 25mm with the 18-55 kit. So I guess I need to know what lens would be appropriate for most dso targets?

Thanks in advance for all thoughts!

[gbeal]

Check to see if your Nikon will work with the old all original manual focus Nikkors. If so, I'd suggest a nice ED180/2.8 or the ED300/4.5.
Gary