The camera unit on the new Nexus 5 is hyped up recently. With Google aiming to release the Nexus 5 in new markets, the demand of US and such countries has also not been fulfilled. It is as predicted and seen with the previous Nexus 4, Nexus phones although priced cheap are always short in supply at launch.

The new Nexus carries a Sony IMX179 sensor which can go up to a maximum of f/2.5 and also house OIS. The small 1/3.2" sensor can achieve up to 800 ISO which is  quite the norm these days in mobile phones.

Have a look at the samples.

Google Nexus 5 Vs Lumia 1020 And Nexus 4

The bottom one is noisier and has used a higher ISO level because the lens and sensor are no match with the 1020.

The top picture is again a clear winner, too much of noise in the bottom picture is evident as detail is hampered and noise prevails.

Although the top picture taken by the lumia 1020 has some evident noise, the bottom picture is not even usable. The small sensor on the Nexus cannot cope with the power of the Large sensor and wider aperture present on the Lumia 1020, because of this the new Nexus  is the clear loser here.

The top picture is the clear winner, colors are better and the overall picture is sharp enough. There is evident proof of a shaky photo in the second picture. OIS helps the Nexus 5 greatly here.

The huge lead of Nexus 5 over its predecessor is evident from these pictures, the Nexus 4'picture does not even expose the details the Nexus 5 does, although both pictures are grainy, the Nexus 5 has the upper hand here.

There is literally no match between the Lumia 1020 and the Nexus 5. The lumia has a huge sensor compared with the tiny 1/3.2" one of Nexus 5 also the impeccable software advantages of the Lumia are sorely missed on any Android.  Nexus 5's camera was a marginal improvement over its predecessor, although Nexuss' have never had top of the class cameras, the one on the Nexus 5 does not disappoint.