Here it is: the very first test featuring the Phase One IQ250 on a technical camera. With Phase One’s release of the world’s first CMOS sensor, our minds at Capture Integration went straight to the applications with technical cameras. Capture Integration is the only dealer in the USA that offers such an expansive technical camera lineup – Cambo, ALPA, Sinar and Arca-Swiss technical cameras are all sold and supported by Capture Integration today. Can’t you tell why we were so excited to run these tests?We already have several other IQ250 tests in the works – stayed tuned for more.

The new Phase One IQ250 digital back has the same sized 1.3x crop factor sensor as the Phase One IQ140. Like the P30, the IQ250 also has large microlenses above its pixel wells – which focus light onto the pixel, allowing for more efficient light gathering. Capture Integration has never recommended using P30/30+ digital backs with technical cameras employing shift, due to issues caused by the size of the microlenses. We are intrigued by the IQ250, but in addition to large microlenses – it has an even smaller pixel pitch than the P30. 5.3µ for the IQ250 vs 6.8µ for the P30, so the challenge for using IQ250 to shift could be even greater.

As soon as we got our hands on the IQ250, we began testing how it performed on a technical camera, incorporating both Schneider XL and Rodenstock HR lenses – with and without rise/fall movement. We were very interested to see how the combination of the small 5.3µ pixel pitch and microlenses reacted to stitching movements, especially when paired with two very differently designed lenses. The results can be found below.

The Testing Parameters

• Phase One IQ250
• Phase One IQ260
• Phase One P30
• Cambo Wide RS AE
• Schneider 35mm XL (No Center Filter)
• Rodenstock 40mm HR (No Center Filter)
• Capture One Pro pre-release for IQ250 support

Testing Objective

The idea behind our test was to objectively view how each of the three test backs performed on a technical camera in less than ideal scenarios, and then in an acceptable scenario.

Each back was tested first without any movement. White balance was sampled in the center of the first image and kept for subsequent images with movement, allowing for objective viewing of the lens cast.

Neither the Schneider 35mm XL or the Rodenstock 40mm HR in this test were used in conjunction with a center filter. Center filters are recommended by Capture Integration for any lens with a focal length wider than 40mm to accommodate for lens cast and vignetting. A center filter was purposefully omitted from this test to further illustrate the effects of lens casting during wide angle movement in order to push the backs to their limit of recovery. For a further explanation of recommended lens and digital back pairings, please visit Phase One’s Knowledge Base article.

When viewing these tests, it is important to note that the IQ260’s sensor is 1.3x larger than the sensor of the IQ250 and P30. In effect, even though the movement is the same on the body, the sensor of the IQ260 reaches a greater distance in the image circle than the P30 or the IQ250. Due to the IQ260’s full frame sensor, the coverage is greater. This is displayed below.

The Test

Up first was the Phase One IQ250

The Phase One IQ250 exhibited acceptable lens casting on the Schneider 35mm with no movement. 5mm of rise and shift brought significant lens casting in the typical areas for such movement and extreme casting with 10mm movement. This casting can be attributed to the large microlenses – collecting light at harsh angles. This phenomenon is well documented, and is expected, as the Schneider 35mm rear optic placement is closer to the CCD plane, which creates a narrow acute angle for light to reach the CCD.

Below are all three backs tested with the Schneider 35mm XL.

We then tested the Phase One IQ250 with a Rodenstock 40mm HR.

As expected, the Phase One IQ250 performed much better under the Rodenstock 40mm HR. This is a perfect example of the difference between Rodenstock and Schneider wide angle glass. The benefits of wide angle Rodenstock HR lenses are not isolated to backs with large area microlenses like the IQ250 and P30, but are also apparent on other backs like the Phase One IQ280 with a small pixel pitch of 5.2µ.

Below is the Phase One IQ250 compared with the P30 and IQ260 using the same Rodenstock 40mm HR.

Summary

While there is considerable excitement for the possibilities for the IQ250 as a potential technical camera solution – it features far better Live View (test coming soon) than any previous digital back, and has expansive ISO capability  (test coming soon) – the reality is that at best it has potential but with some limitations on lenses and movements.

Capture Integration takes tremendous care in discussing with our clients the solutions they purchase from us. We want to make sure they understand exactly what they’re buying, and exactly how it will perform, no matter what the manufacturer marketing/data sheets say.

The Phase One IQ250 is a groundbreaking new product. We will continue to perform more testing and post our results so that our clients are able able to view and critique the results.

For a demo or any questions relating to the Phase One IQ250, please give us a call! We will continue to post our technical testing to the Capture Integration blog. Call or email us if you would like to see specific testing.