[gregbradley]

Camera lenses for astrophotography:

Nikon 180mm F2.8 ED about $500-600. A good lens a bit of chromatic aberration but correctable in processing.

Nikon 50mm F1.8G 1.8D both are very good wide open. I have used the 1.8g with a Proline 16803 and adapter successfully. Canon 50mm would be the same as they seem virtually identical as lenses.

Nikon 85mm F1.8g coma and chromatic aberration until F2.8, Most fast lenses are like that. Wideopen you get coma and or chromatic aberration which stops around F2.8 so not much gain to pay for the F1.8.

Nikon 105 F2.5 AIS is a beauty probably under $200. Metal, aperture ring, and well made.

These are all evaluated using either a Proline 16803 or STL11.
Pentax 67:

55 F4 - not bad, needs to be stopped down to F5.6 to counter coma. $100 or less.

75mm F4.5 a beauty. I used this one recently and it works really really well. $125 or so.
Perhaps a bit slow.

165 F2.8 brilliant lens, cheap, sharp wide open, no chromatic aberration one of my favourites. $200 or less.

300mm F4 $300-450 (non ED version). Good for narrowband. My adapter has a small amount of play and this can cause this lens to rock slightly making subs on one side of the meridian not match well with subs on the other side. It may be OK now as I have a later filter wheel and the adapter can screw in deeper. The one I had I needed to have it unscrewed a little bit so the adapter did not hit and stop the filter wheel filter hold in screws.

300mm F4 EDIF (around $1500) never used it but this is the one. Marco has used it extensively and I have seen other images using it. A ripper. There is also a 400mm F4 EDIF.

Zeiss 300mm. Never used one but seen images by Wolfgang Promper that are superb. Probably an expensive lens as most Zeiss are.
Pentax 200mm SMC Marc on this site uses this and lots of fabulous examples.

It depends on what you want to image. 50mm is a good all round widefield lens that are generally easy to use and most are probably pretty good as 50mm seems to be easy to manufacture.

100-200mm gets a fair bit closer in. 300mm is now like an FSQ with a reducer but smaller aperture lens. More demanding of flex and strength.

I have an adapter for the Nikon lenses from FLI. I also got a Pentax 67 adapter made up custom by Precise Parts.

Focusing can be done manually but its tricky. I used to use a FLI PDF focuser with adapters and that worked really well. The FLI Atlas would work even better.

My Zeiss FE 55mm F1.8 may or may not be suitable as Sony FE is something like 24mm backfocus whereas Canikon are more like 48mm.
The FE lenses are designed for Sony mirrorless and the short backfocus is why virtually any lens ever made will work with an adapter on Sony and Fuji mirrorless.

Modern Canikon lenses are a bit of a problem as they are electronic and most do not have aperture rings anymore so you need to jam up the little sliding prong that holds the aperture open.

Widefield nightscape lenses:

Nikon 29 F2.8 - not very good.
Zeiss FE 35 F2.8 a bit of chromatic aberration wide open. Not bad not great. Needs to be stopped down.
Zeiss FE at F4 its very nice. More wide open a bit too much chromatic aberration but this is one of the top 4 lenses listed in DXO Mark and a super sensational lens for regular photography. Super sharp. A magnificent lens.
Nikon 14-24 F2.8ED - the king of the widefields with perhaps the Zeiss 15mm F2.8 only better. The new Canon 11-24 is probably also as good if not better but very expensive. I was not able to use this lens on my Proline as the adapter spacing must be a tad off and this lens needs it to be bang on.
Samyang 24 F1.4 Good at F2 onwards. A good lens and sharp to the corners no coma after F2.

APSC;

Fuji 18-55 F2.8 a remarkably stunning lens for a kit lens. Fuji kicked a big goal with this lens.
Fuji 14mm F2.8 another remarkable lens. Metal and aperture rings although electronic fly by wire aperture. That would make it hard to put on a CCD camera.
Fuji 35mm F1.4 not bad. Not great, again you need to stop these lenses down for them to work. Astro work is far more demanding than terrestrial in this regards and you see the coma and chromatic aberrations that don't show up too much in terrestrial work.

My favourites are:

Nikon 14-24
Pentax 67 75 F4.5 and 165 F2.8
Nikon 50m 1.8g and 1.8d
Zeiss FE 55 1.8 on the Sony A7r.

I don't know a lot about Canon lenses apart from anything L and a prime is likely to be very good. Zooms of any brand except perhaps Fuji are probably a no no. I tried a Yashica Zeiss 28-70 zoom and it was not too bad but chromatic aberration required it to be stopped down a lot.

Greg.