A7RII versus Pentax 645Z

At a workshop given by John Denton for The Flash Centre, with Elinchrom lighting and Pentax 645Z demonstration. model Laura posed for a comparison pair of shots using the Pentax with 90mm macro lens and the A7RII equipped I regret to say with a much inferior lens, the basic 28-70mm.

To compare the quality bear in mind that the Pentax was ISO 200 at f/5.6 and the Sony was ISO 400 at f/8 as I felt it necessary to stop down – I should not have, as I had forgotten than the 28-70mm is sharper at f/5.6 than f/8, which introduces local unsharpness to the left hand end of the image (landscape) and did with all three samples I have used. This means the model’s face is smeared on the Sony shot, because this lens can’t produce a sharp image under these conditions in that part of the frame. Yes, I’ve had some OK results, but this was the first time I used the 28-70mm on the A7RII. It is OK on the A7II and A7S, as the blur is not so visible at those magnifications. It’s really not good on the A7R or A7RII.

So, please examine everything except the face…

This is the Pentax shot. Despite the matched for theoretical exposure, it is much darker and the ISO 200 is only equal to ISO 100 in Sony terms. Daylight balance set for the flash, Adobe Camera Standard profile since no other is available.

Here is the full resolution link to 146MB (if opened or downloaded) original:

http://www.pbase.com/davidkilpatrick/image/160895282

This is the Sony shot. The Camera Portrait profile in ACR gave much improved skin tones, so I’ve used this. The pBase link appears to have scaled the images proprotionally, so the 42Mp image is correctly smaller than the 50Mp.

Here is the link to the 120MB original:

http://www.pbase.com/davidkilpatrick/image/160895292

Enjoy – John teaches retouching and has set up deliberately harsh lighting to create over-sharp skin and too much detail, which he then expertly ‘fixes’. My shots are un-fixed. His workshops are worth every penny as he delivers an entire set of notes and his Photoshop actions to all delegates.

– David Kilpatrick