Hi,
Thanks for your comments, Steve, always appreciated. I can agree that resolution at actual pixel levels may not be as important as some of us may think. But I also feel that many customers buy MF because the image quality and resolution may be a significant part of that.
Another point may be that usability, focus and lens quality may be factors in choosing MF systems as the sensor itself is often the same. For instance, the IQ-250, the new CMOS-based Hasselblad and the Pentax 645Z use the same sensor and I am pretty sure that Leaf and Phase MFDs have much in common. So lenses, usability, vibrations and focusing ability may be important differentiators. For instance the Hasselblad has now live view on the back, can be a disadvantage in the field, but "True Focus" may be helpful in the studio.
Having followed Lloyds writings a long time I have an appreciation of his work. Generally he shoots different subjects, including a large mural, landscape and so on. The kind of 3D scene in this test is useful to check bookeh. The way he works is to find in focus areas and analyze them.
Having a lot of experience with different lenses helps in seeing different issues, like the very obvious magenta/blue fringing. I can see a lot of that on my Zeiss lenses of older design. The MTF data that DHW publishes on those lenses is quite reminiscent of the corresponding MTF data for Zeiss lenses I have, which my be an indication that they are older designs. MTF data for the LS lenses for the Phase One cameras is in a different league, but it needs to be kept in mind that those data are shown at higher frequency than older data. European recommendations used to be 10/20/40 lp/mm but the LS lenses are shown at 15/30/60 lp/mm.
Saying that MTF data is not relevant is simply stupid. That is the data that lens designers use for constructing the lenses. Well, they also use ray tracing, optical bench analysis and so on. All that work is done in software based at the design state.
To me it seems that Eric Hiss comments are more about discrediting Lloyd than being constructive. A good example is him talking about the shutter vibration issue of the A7r. Lloyd has noted it first, I have seen it analysed to death but it is very clear that the problem is real. It is a small vibration degrading the image. Not very obvious, not like double contours, but the system may not deliver if used in the affected speed range if used with high quality lenses. Jim Kasson has published around a dozen articles of the issue. It is an issue Sony needs to fix.
If someone using the A7r is not affected by the issue, congratulation to that person. The vibration is obviously depending on system mass, pivot point, moment of inertia, but it is pretty obvious that the issue is real. It is good to be aware of the issue if you buy a 5k$ lens and a 2k$ camera body for optimum quality.
So using the A7r shutter vibration issue to discredit Lloyd's testing, is not only stupid, ignorant but also dishonest. Offering a system for an independent tester and than discrediting the results seems highly unprofessional to me. If you send a system for test you face the consequences. Has Eric Hiss checked out the diglloyd site before handling out equipment for test he would have known what to expect.
Remark: I feel obliged to mention that I did have a significant argument with Eric Hiss on these forums, so it may be that I have an axe to grind.
Best regards
Erik
I find that Lloyd tends to focus (no pun intended) on focus issues and lens performance. He has kind of an exhaustive library of tests with lots of different lenses. I would say going in, that handing him a camera to review is going to result in negative issues pointed out prominently, and indeed, emphasized. There are a scant few cameras/lenses that he has found among the many he's reviewed that he's expressed enthusiasm for without too much highlight on the compromises.
That's fine. As Edmund sort of said - he works within his own somewhat limited testing perspective.
I do kind of question the results and the environment, especially given Eric's added narrative of events. 3D environment to check edge to edge focus? The end of a branch hovering in the air over a gushing stream is not sharp? Just shooting anything with a stiff wind can create challenges - even if the subject matter is static. I appreciate that he pays so much attention to the glass - that is absolutely right. But I wouldn't draw firm conclusions from his analysis - I say put in in your hands and see how you do. Kudos to Eric for tagging along - it could have been worse without you on hand. Too bad you didn't have a Credo 80 for him (not that it would have made much difference).
Steve Hendrix
Capture Integration
