Phase One IQ3 80MP vs Phase One IQ4 150MP read noise comparison

Phase One IQ3 80MP

The Phase One IQ3 80MP was measured at 7 ISO settings from ISO 50 to ISO 3200. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (50) read noise is 20.25 DN. A second gain (dual gain) kicks in at ISO 1600, cutting input-referred read noise by about 1.5 stop. From ISO 1600 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise.

Phase One IQ4 150MP

The Phase One IQ4 150MP was measured at 28 ISO settings from ISO 50 to ISO 25600. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (100) read noise is 4.17 DN, or 3.5 electrons at the sensor. From ISO 20000 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Full well at base ISO is about 54,029 electrons; unity gain is around ISO 80.

Phase One IQ3 80MP vs Phase One IQ4 150MP read noise table

ISO	Phase One IQ3 80MP	Phase One IQ4 150MP
50	20.252	4.199
64	–	4.141
80	–	4.056
100	20.252	4.170
125	–	4.112
160	–	4.199
200	30.484	7.568
250	–	7.674
320	–	7.727
400	54.948	6.821
500	–	6.727
640	–	7.062
800	107.635	12.906
1000	–	13.642
1250	–	13.361
1600	78.793	25.813
2000	–	26.173
2500	–	25.634
3200	150.123	50.213
4000	–	49.867
5000	–	49.522
6400	–	95.670
8000	–	103.250
10000	–	97.006
12800	–	181.019
16000	–	177.294
20000	–	184.823
25600	–	372.217

Popular comparisons

All cameras · Open the full tool

Phase One IQ3 80MP vs Phase One IQ4 150MP: read noise comparison