Re: Comprehensive Testing: Results & Observations with Pentax 645 Lenses used on the
Having trawled through this, I'm eternally grateful to Dave for doing it, and GetDPI for being the place where someone would post such info.
However, I'm still left wondering how I would put a kit together. I am coming from a Hasselblad H4D 40 with 35-90, 150 and 210 lenses. These are all excellent lenses, and it never occurred to me that there may be much in the way of inter-unit variation.
My initial thought for a replacement was to buy a D800E with Zeiss glass, and a Nikon or two for AF. I then remembered the 645D. Having had a 645NII in the past, the attraction was very strong. I also loathe 3:2 ratio.
When I read the reviews, the words 'stellar' or 'excellent' seem to be missing. Additionally, inter-unit variation seems to exist often. I really don't want to get into buying and selling until I get a good lense.
Am I misreading this, or is that just the reality of Pentax today?
Hi Jeff,
Am currently at work so I apologize if my response at the monment is brief. Tom mentioned some of the exceptional performing lenses in the 645 system that do well on the 645D body and I can certainly elbaorate my actual own personal experiences with them. As for sample to sample variability as posted in my comprehenisve lens testing, it's important to note a few things. Everyone's level of acceptability of a particular lens sample performance varies as to what is acceptable or not. Variations exisit and to what degree depends on which lens is being refered to. It not all that unlike some other medium format systems where sample differences could also be seen to varying degrees.
Another factor to consider is intented use and output. If it's for large sized large format printing, then of course differences often seen in lens samples may and can often be quite noticable. There are some cases where it didn't take a 24x36 inch print to relaize these differences. How important they are to ones actual work is of course both subject dependent as well as how exacting a lens performance is to the individual.
With all this said, I don't want you to get the impression that you have to go on a "looking for a needle in a haystack" approach to find good lenses for the 645D...on the contrary. Just keep in mind some of the findings I posted and for key focal length lenses that you will use primarily, take the usual precautions in purchasing a particualar sample lens. It's not very different than those who shoot Nikon and look for and expect a properly aligned and exceptional performaing sample of a high performance lens for that system. As you can see in the Nikon formums, even the best most expensive glass often has considerable variation and some look for a "good" sample. The recent Sigma 35mm f1.4 is a good example.
Keep in mind that many of these Pentax 645 lensees were designed in the film era, so they didn't require the as precise tolerances that are required by high performance digital cameras of today. Even Pentax and other Medium format digital manufacturers noted this when their users would try and use legacy film era lenses.
With all this said, maybe the key think to note with te 645D is AF fine tuning of each lens purchased. I found this was more important than anything else to exact the best possible performance from 645 lenses on the 645D. I am so thankful Pentax included this feature on the 645D.
After having shot with both the D800e as well as the 645D, I personally feel there is a substatial difference in the look of the files, espcially when printed large and there is a strong case for shooting with MFD in the 40MP range. Each system has it's strengths and weaknesses and I would venture a guess that the very reasons you or someone else enjoyed shooting with the hassy system over 35mm DSLR's would again find the same advantages shooting with the 645D. The system is an exceptional value and is one of the reasons is still extremely popular. Again these are simply my own personal views.
Dave (D&A)
