Pentax 645D review

Pentax's 40Mp medium format camera put to the test

Pentax 645D
This 40 million pixel medium format digital camera is priced high but performs well

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We shoot a specially designed chart in carefully controlled conditions and the resulting images are analysed using the DXO Analyzer software to generate the graphs below.

For more more details on how to interpret our test data, check out our full explanation of our noise and dynamic range tests.

Our labs data for the Pentax 645D is compared against the Nikon D3x and Canon EOS 1Ds MKIII. While these DSLRs have smaller sensors and are considerably cheaper (although not that cheap), all three cameras are perfectly suited to studio use.

Our analysis shows that all three cameras produce excellent results, but for both noise and dynamic range the Nikon D3x and Canon EOS 1Ds MK III just have the edge over the Pentax 645D.

JPEG Signal to noise ratio

A high signal to noise ratio (SNR) indicates a cleaner and better quality image.

Pentax 645d jpeg signal to noise ratio

Pentax 645d jpeg signal to noise ratio

Our results for the JPEG images from the Pentax 645D indicate that despite the increase sensor size it generates a lower signal to noise ratio than the Nikon D3x and Canon EOS 1Ds MKIII.

JPEG Dynamic range

Pentax 645d jpeg dynamic range

Pentax 645d jpeg dynamic range

This chart indicates that the Pentax 645D's JPEGs compare well against the Canon EOS 1Ds MK III up to a sensitivity of ISO 400.

For more more details on how to interpret our test data, check out our full explanation of our noise and dynamic range tests.

RAW Signal to noise ratio

A high signal to noise ratio (SNR) indicates a cleaner and better quality image.

Pentax 645d raw signal to noise ratio

Pentax 645d raw signal to noise ratio

Raw images as with JPEGs from the Pentax 645D show a lower result for signal to noise ratio than both the Nikon D3x and Canon EOS 1Ds MKIII.

Raw Dynamic range

Pentax 645d raw dynamic range

Pentax 645d raw dynamic range



This chart indicates that the Pentax 645D's raw files score well at the lower end of the sensitivity range, however these results are dwafed by the Nikon D3x and Canon EOS 1Ds MK III.

For more more details on how to interpret our test data, check out our full explanation of our noise and dynamic range tests.

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