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Forum: Pentax Medium Format 01-22-2011, 11:43 PM  
Early thoughts on the 645D
Posted By Nebster
Replies: 3
Views: 2,790
Dear friends,

I received my 645D a little over a month ago. Since then, I have been acquiring lenses, learning how to push the buttons on the camera, learning how to use a new image editor, and then waiting for a chance to go shoot "for real" and come home and post-process the results. Now that that's all done, I feel like I can write some comments of my own. This forum has been immensely helpful in making my switch, and so perhaps these thoughts will "pay it forward" to the next few considerers.

I should start by explaining my photographic background. I have shot with almost every Canon DSLR since the original D30. For the last year, I have been using the 1d4 exclusively -- by far the best per-pixel sensor in the Canon lineup. My experience is that that sensor can crush the 5d2 or a 1ds3 in a lot of the non-ideal scenarios in which people like me end up shooting. High ISO? Better. Mis-exposed a little? More DR to work with. Color and "tonality"? Simply superior. Each in small ways, but enough that it really adds up to more keepers in more situations. Now, I'm not smart enough to quantify everything, nor do I particular relish the thought of trying to be that scientific with something that is an art tool, but I can see it all in the results. I shoot exclusively with fast primes -- really, only a couple ever go "in my bag," and I often just stick with one for any given single outing.

I almost always shoot handheld and "on the run." Occasionally I find landscapes or people to try to capture, but my real love is abstract and macro. Usually my target is large-format prints; I have a recent Canon 44" that lovingly writes to baryta papers that I either mat and frame or front-mount onto acrylic.

And so it was with great excitement that a MF option finally appeared that looked like it would fit my requirements, not feel too far afield from the SLR experience I know very well, and also not be priced well into the stratosphere.

I think I was one of the earlier folks to get the 645D, because I had no trouble procuring used lenses for about 10 days back in mid-December. Now it is almost impossible; clearly, all of you are scouring the internet and snapping up the rest of them within seconds of them becoming available. :) Fair enough. It turns out, in the rush, I ended up with extra copies of a few lenses. I will be making those available soon.

Enough babbling. Let me start with some positive observations.

Image quality is stellar. Very similar in DR and tonality to the 1d4 sensor, which I suspect makes pixel quality on par with the newest Nikon sensors and the rest of the modern MF sensors. Noise degradation is quite graceful; ISO 800 is not scary at all. 1600 is workable if the effect is appropriate for the scene, which I find it often is.

Handling is great. I'm not too picky about interfaces, but I do like non-modal primary. There are some tiny things I dislike about the 645D, but by and large it is nice. I find the mode selector wheel sometimes ends up turned even without depressing the center lock button. And I would like to see previews render faster. (Why do we have to block while we wait for the image data to be written to disk? Wasn't DMA was invented 25 years ago?)

The weatherproofing works. I used the camera in a two-hour off-and-on downpour and it came through fine. And it seems to tolerate falling onto the concrete pretty well; I already put some scratches in the bottom corner of mine. :)

Now for the crux concern.

Focusing. Focusing. Did I mention focusing? I think it's a combination of the bigger sensor, the darker lenses, the dodgy viewfinder, and the incredible resolution. Combine that with the fact that I am often shooting flat subjects that demand sharpness corner-to-corner -- in other words, I often am literally shooting those brick walls that are so often poo-pooed by the anti-pixel-peepers. My initial keep rate was something like 15%. I switched to manual focus, started paying much closer attention, slowed down, adjusted my stance a lot, increased shutter speeds by 2x, stopped down an extra stop, and now I might get 25% that I'm at least marginally happy with. I would guess that's about half my success rate with the DSLR... so it's not horrible, but it's really, really hard work nonetheless. I do like that it forces me to go a little slower, which is probably better for my eye and the results.

What about lenses?

The new 55mm promptly went back to the Pentax Web Store. (They still have not credited my refund, even though they signed for the delivery 10 days ago.)

I ended up with The 120mm in A and FA versions. (Actually, somehow I messed up and purchased TWO FA versions and one A, strangely. I guess I was moving fast, since I could sense the market shifting under my fingers over the course of several days.) The one FA I tested seems very close if not identically sharp to the A; both are great right out to the edge. The FA is not reliable enough for my style of shooting, though in casual tests at wide aperture it does fine for "10 megapixel" results and for captures that would go to web or a small photo book. I prefer to focus with the A, because the mechanism allows for more precision, but, frankly, once I get in the ballpark, tiny motions of my head/camera will render any further lens adjustment moot. It probably just feels cooler to focus it, and that must be why I like it more. :)

I also have the 75/2.8 A. It also looks good to the edge, though I have not used it critically or sufficiently yet to know for sure. Wonderful OOF rendering though with this big sensor. Results remind me of the Canon 135/2. I will end up shooting more with this lens in future adventures, and so I reserve the right revise my opinion later.

I lucked into an 80-160 FA as well. To my eye, this lens has higher contrast but slightly lower sharpness overall compared to the 120mm. That is unscientific and from shooting mostly within the shorter half of its range. It is definitely a good lens. I would say resolving capability in the center is 90% of the macro lens and maybe 80% at the corner. It seems well-managed, though, and I won't hesitate to use it. I can't comment on it past about 120mm.

Finally, on lenses, it seems clear that there is enormous sample variation, so my data is not statistically significant. Hopefully more people will post their results as well.

Other factors and wishes

I love the configurable zoom setting on the image review. It's good enough that I can tell whether I got focus in the center with a couple of button presses. However, I also want to see the corners. It would be cool if there were a firmware feature that let you either see all the corners in a 4-up view or move quickly to each corner with a button press. It's too time-consuming to scroll or zoom/scroll to them.

Obviously we all want live view. This is much less important, though, for those of us dumb enough to try to shoot handheld.

My casual testing on a tripod with autofocus suggests that the AF is precision-limited. It seemed accurate but not precise in my short experiments. In other words, either because of motor slop, motion slop, or phase-detection slop, it could not hit it on the nose every time. I know, I should have done it 100 times and plotted the results to see if we could observe a Gaussian distribution. :) But the fact is that it's not good enough on my lenses, with my copy of the camera, for my eyes, to fully resolve to the sensor's limit. It's a handy tool for casual shooting if you're okay with some misses and final results that will be closer to 10MP than 40.

A lot of people seem happy with results at f/11 or f/14, but I see quality-droop at these apertures with the 120mm. It goes from "amazing" to "this is okay, but I'd get almost the same result with my 1d4 except twice as often in focus" for me. Since I have the grand luxury of not caring how many images I throw out (I only have a few walls to hang big pictures on anyway), I will stick with f/5.6 to f/8. I suggest you do, too, if you want the optimum results.

The battery life is great. Even in the cold. For my kind of shooting, I'm not even sure if I'll spring the $40 for an extra one. The charger is almost the same volume and weight. Okay, if I get a second body, I'll carry two batteries. :)

I don't care for the metal triangles that provide the clip point for a shoulder strap. They click against the camera too much. Sometimes I like to move silently, and it's hard with this camera.

The really deep hand grip is incredible. I've never used a camera with one, and it almost obviates the need for a hand strap. I'd still like a hand strap, but I can come very close just by jamming my fingers in that giant cavern of a grip.

Summary, so far...

It's a clear winner. I've lost out about 15% of the scenarios in which I used to be able to shoot with my 1d4 (darker stuff, image-stabilized situations, fast-action) but picked up probably a 50% bigger printable image in 50% of the scenarios I shoot -- and those are the ones where I tend to want to make a big art print anyway. I guess in a dream world, if I had a Sherpa and unlimited money, I'd keep the 1d4 with the 200/2 and 135/2 on standby and blast away with this guy most of the time. But, if you're kind of like me in your style and approach, and especially if you are not inclined to drag lots of gear everywhere with you, this is a legitimate contender.

I look forward to revisiting this early review as the months go by. If you'd like to see some images from my Mexico trip, including lots of "brick walls," feel free to check out the gallery here:

the pixel4.net gallery | Cozumel

(Please note that there are some "non art" shots mixed in, including several that are not up to critical standards but that get a place in the gallery so various blog readers and family members can be happy. Still, some of those even illustrate the wonderful OOF rendering this camera can produce.)
Forum: Pentax Medium Format 01-05-2011, 12:16 PM  
Lens hood for 120mm/4 A macro?
Posted By Nebster
Replies: 6
Views: 2,266
Great, thanks. Now to find one...
Forum: Pentax Medium Format 01-05-2011, 12:59 AM  
Lens hood for 120mm/4 A macro?
Posted By Nebster
Replies: 6
Views: 2,266
Hi everyone,

I have a FA and A version of this lens. The FA has a hood. The A doesn't seem to have the little bits needed to get a hood to affix to it.

Is there supposed to be a way to put a hood on this lens?
Forum: Pentax Medium Format 12-23-2010, 08:31 PM  
It this a true statement on lens for the 645D
Posted By Nebster
Replies: 36
Views: 9,045
My short set of experiments says that the focus-assist isn't good enough. My eye is better. But, if you do want to use it, you may observe that it will work slightly better in one zoom direction than the other.
Forum: Pentax Medium Format 12-22-2010, 02:33 PM  
It this a true statement on lens for the 645D
Posted By Nebster
Replies: 36
Views: 9,045
I've begun early experiments with A and FA lenses (I ended up with one of each in the 120/4 macro, as it happens). My take is that it's darn hard to get critical focus with either auto or manual focus. Just really, really hard.

Now, accepting that for a moment, I have not found the autofocus to give me much higher a hit rate than manual so far. Admittedly, my sample size is small, my experience is short, and I am handholding at a lot of close- and mid-range targets so even my own motion will impact the focus. But for the type of walk-around shooting I do, I'm skeptical of both systems, and I predict it'll be necessary to focus-bracket as elho_cid suggests.
Forum: Pentax Medium Format 12-21-2010, 02:50 PM  
eyecup has fallen off my 645d
Posted By Nebster
Replies: 8
Views: 2,681
Is the big eye cup supposed to go over the small one, or are you supposed to switch them? I've done the latter, and I've had my big eye cup fall off three times in three days just wandering around the house with it.
Forum: Pentax Medium Format 12-20-2010, 09:13 PM  
Lenses came...finally
Posted By Nebster
Replies: 7
Views: 2,141
Shane, good to hear. I have the same two lenses. I am curious: what Canon glass are you comparing to? Just interested to see. My opportunities to shoot have been too limited to draw any conclusions yet.

Ben
Forum: Pentax Medium Format 12-18-2010, 07:31 PM  
FA lens not auto-focusing on 645D?
Posted By Nebster
Replies: 4
Views: 2,261
Yeah, hehe. I started my search for lenses a few days ago and was getting a little frustrated with how hard they were to find. Then I stumbled on this (supposedly excellent) one on KEH at a price that seemed too low. Needless to say... pay first, ask questions later was my philosophy at that point. Hehe.

It works great, btw. No light to try some shots yet, but I'll experiment over the next few days.
Forum: Pentax Medium Format 12-18-2010, 07:30 PM  
FA lens not auto-focusing on 645D?
Posted By Nebster
Replies: 4
Views: 2,261
Ah ha! Thanks. I never would have figured that out on my own. :)
Forum: Pentax Medium Format 12-18-2010, 10:51 AM  
FA lens not auto-focusing on 645D?
Posted By Nebster
Replies: 4
Views: 2,261
Hi all,

I just became a Pentax Person with a 645D that arrived yesterday. Cool! I have the new 55mm lens that seems to be working fine. I also found an FA 80-160mm on KEH for a steal that arrived today. Unfortunately, I can't figure out if its autofocus mechanism is defective... or if my understanding of how it should work is.

I put the lens on. Nothing happens when I press the AF button. Is there anything I could be missing?

Ben
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