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Forum: Sold Items 08-29-2017, 09:20 PM  
For Sale - Sold: Pentax 645Z Medium Format Camera (Price Lowered!)
Posted By harklee
Replies: 0
Views: 840
PentaxForums.com Marketplace Listing

Item for Sale
Pentax 645Z Medium Format Camera

Asking Price
4,150.00 USD

Item Location
Sunnyvale (United States)

Item Description
Up for sale is a Pentax 645Z in an excellent condition. The looks almost new with no cosmetic imperfections and is in a perfect working condition. I have been using it since January of 2015. Including an extra battery charger and several backup batteries.

Are you the original owner of the item being sold?
Yes

Are you selling or trading this item?
Selling

Item Condition (Key)
Used
Excellent

Shipping Destinations
Worldwide

Shipping Charge
Ships Free within the Lower 48

Shipping Services
USPS

Accepted Payment Types
PayPal Check/Money Order

Return Policy & Additional Details
The item may be returned within 3 days of receipt if it is not found to be as described in this listing. No returns will be accepted for any other reason. Buyer is responsible for the return shipping, and the item must be received in the same condition as it was in when sold.

Please send me a private message if interested in the item!
Forum: Pentax Medium Format 05-12-2017, 06:56 PM  
Why DFA25/4 and DA25/4 Discontinued So Quick?
Posted By harklee
Replies: 23
Views: 4,966
I was always under the impression that it was more of a cost and manufacturing issue than quality. When I got to talk to the one of the chief engineers at Pentax about the differences between the D-FA and the DA shortly after they released the DA, he, in broken english, managed to get across "hold onto it. What you have is a great piece of engineering and will be missed". I thought it was rather odd at that time, but he couldn't seem to divulge anymore info. The fact that they had to re-engineer a DA version, and then discontinued both seems to imply that there were some manufacturing problems (maybe cost too high).
Forum: Sold Items 02-08-2016, 01:36 AM  
For Sale - Sold: Pentax 645Z 51.4MP Medium Format Camera Like New
Posted By harklee
Replies: 1
Views: 1,154
PentaxForums.com Marketplace Listing

Item for Sale
Pentax 645Z 51.4MP Medium Format Camera Like New

Asking Price
5,000.00 USD

Item Location
Sunnyvale (United States)

Item Description
Up for sale is a 645Z in pristine condition. I purchased two bodies in mid 2014, and this one has been kept as a backup and has seen occasional use. The camera is like new, no scratches or imperfections. Comes with the original box and packaging, also offering free shipping.

Are you the original owner of the item being sold?
Yes

Are you selling or trading this item?
Selling

Item Condition (Key)
Used
Mint

Shipping Destinations
Worldwide

Shipping Charge
Free

Shipping Services
UPS

Accepted Payment Types
PayPal

Return Policy & Additional Details
Offers 7 day return, buyer pays for the return shipping.

Please send me a private message if interested in the item!
Forum: Pentax Medium Format 12-24-2015, 02:21 PM  
Review - The 645 System for Landscape Photography
Posted By harklee
Replies: 33
Views: 9,265
Thank you Jonathan! I will try to add more images as soon as they are ready.


Thanks, markoneswift, I also appreciate mentioning your favorites, it's very helpful to understand what people like better than the others.


Thanks for the detailed comment, Remco. Yes, the same workflow can be applied to any format as long as image resolution is the top priority. By the way, I just checked out your gallery, and I really liked the one titled 'The reflection at the end'. A great composition that leads viewers deeper into the picture. Keep up the great work.


Thanks a lot for the compliment, Tim - a fellow Californian! The 645 film cameras were also my favorites, and I still get to take them out once in a while. I think the moment they announce the successor, the 645z will see a major price drop and become a value proposition with ultimate performance for many; this covers even a vast majority of print-oriented guys, because the camera already has enough potential for exhibition quality prints.


Thanks a lot, btnapa. I guess you may be contemplating the new full frame as your next camera? Quite curious what they will come up with. :)


Really appreciate it, Jimmy. I hope I can do a better job next time, too many minor errors to clean up. I also checked out your photos, very nice macros!


Thank you very much, FOX!


So much kindness in your comment, David. Those words will be really helpful to keep myself motivated and take these overweight pieces of gear farther than before. Thank you.


Many thanks for the detailed comment, Tom. I agree with everything you said. There must have been a significant amount of confusion within the organization during these acquisitions. And it's great that Ricoh seems to have a good understanding of Pentax's legacy. Let’s hope they will take this brand to the next level.


Thanks a lot, Ross, I will try to post more often and be part of the group!


I was thinking the exact same thing myself, though I have to admit that I haven’t got a chance to use the pixel shift system. Since even the most stationary landscapes tend to have subtle movement in them, I am not entirely sure how it will pan out, but that’s certainly a great way to beat the diffraction. Thanks a lot for your input, Scintilla.


Thanks a lot, pinholecam. I guess I am a little too old and beat up to do one of those ‘bragging about the new toy’ kind of reviews, haha. But I will give it a shot next time.


I am really grateful for the kind words, Pioneer. I will try to come back with better images.


Thank you so much, Don!


Thanks Mike, much appreciated.


Thanks Franc! I will update the review regularly with new images.


Cannot thank you enough for the kind words, thanks Lenny!


Wows, I didn’t think anyone would remember the 645D review and images, thank you so much! And my apologies for the sporadic presence. I am not really very active on the internet, but I will definitely write more on a regular basis and keep you guys posted. Thanks Rondec!


Agreed; looks like Pentax is in better hands. I recently got a chance to talk with someone from the U.S. headquarters, and they seem to be doing a much better job too. Although it seems that the customer service can use some improvement.


There’s so much information in your comment - I really appreciate your taking time and writing in detail. About the lenses, I am also quite curious if it is technically achievable to somewhat downsize them without sacrificing the optical performance. They’ve done an excellent job with the 28-45mm, but the last thing you want to do as a nature photographer is to have three equally heavy, large lenses in your muti-day pack. Hope they will find a good balance somewhere.
I’ve always drawn to panoramas and try to do more, but it’s also very challenging to execute well when the light changes by the second and you need to secure certain depth of field. Using a telephoto lens to do gigapixel panoramas is very interesting, but it faces the same issues; ever-chaning light and depth of field. Though I am very interested in using one of these automated panning heads, I will let you know if I get a chance to try one out. Thanks for the link too, I will make sure to check it out.


Thanks pinholecam! Much appreciated!


Tex, I really appreciate your taking time and expressing your thoughts in an articulate manner. Also, I wholeheartedly agree with your sentiment about the titles. To make an excuse, I feel quite out of breath by the time I get to name a photograph. From the idea to capturing the light and processing the image, it’s a long and painful process. And I tend to often resort to rather simple and cheesy titles, which may or may not resonate with the viewers’ interpretations. The titles do not come without contemplation (as there is a story behind each one), but I absolutely agree that they need to be better. Every single time I learn that there is a very fine line; titles can accentuate the theme and make the photos come alive, or also it can cheapen them indefinitely. So thank you so much for the input, I will do a better job in the future.


Thanks Ron!


Thanks a lot Mike! About the website thing – yeah I wanted to put the images in a separate format since I found it a little difficult to get them to blend with the text in the current format.


Thanks, David! I will try to do a better job in the future!


Yes Gyroscope, I think the 645Z scratches pretty much all the itches one has as a photographer. I also agree with your sentiment about the 28-45mm; it’s one of the best lenses I’ve ever used. Many thanks for the comment.


Agreed, tuco. That is something that I will be interested in too.


Thanks algrove!


Hi hsteeves, I think you are absolutely right about my background influencing the way I photograph; a form of occupational obsession. Thanks a lot for the kind words.
Forum: Pentax Medium Format 12-17-2015, 11:17 PM  
Review - The 645 System for Landscape Photography
Posted By harklee
Replies: 33
Views: 9,265
Thanks everyone for the kind words, I will individually respond to your comment sometime tomorrow when I have full internet access. Thanks!
Forum: Pentax Medium Format 12-17-2015, 03:56 PM  
Review - The 645 System for Landscape Photography
Posted By harklee
Replies: 33
Views: 9,265
1. The Question

“So what does it look like when a nature nut obsessed with large prints gets his hands on the 645 system?”

I think we all wondered about this question. Because, let’s not fool ourselves; the 645 system has always been
for landscape photography. It is not there to be cuddled. It is meant to be covered with flurries in the high Sierra,
beaten by hail in the stormy Grand Canyon, and blasted with sand showers in the scorching Death Valley.

It took five years to build my photography around these expensive chunks of metal and glass, and I think now I
can say a thing or two about them.


2. (More Formal) Introduction

I always thought the 645 system is primarily designed for landscape photography. Having been an old-timer
with the 645N II in a worn-out bag and a heavy user of the 645D and the 645Z since they were first introduced
into the market, that perspective never left my mind nor was ever challenged. Since hauling a 40-pound pack
on a regular basis for backpacking trips in the Sierra cannot be good for my beat up joints, I might have some
suggestions for future improvements, but all of these cameras and lenses stood the tests of the most
unforgiving terrains and elements so far. So I thought there must be a review from who knows a little bit about
landscape photography.

It’s not only the camera but also the photographer that has seen changes over the years. My fixation with the
‘a photograph must be a single exposure’ ideology, stuck in the head for quite sometime especially during the film
days, has seen noticeable compromises, as I’ve learned more about the differences between the way the human
eye sees the world and the way cameras do. And when I was educated more about the physical limitations that
any high-resolution photographic system is subjected to, I decided to take that painful path that embraces new
digital techniques. So this is also a piece about exploring new ways to best utilize the photographic system’s
potential.

Here I wanted to share some of the images that I photographed recently, as a way to examine the capabilities
of the Pentax 645 system; especially the new 645Z and some of the key optical pieces that have found space
in my bag. As the prime technical objective of my work is to produce large prints of the highest quality, I thought
providing some insights into the pixel-level quality, also not in its raw form, but in the final phase of the images
after all processing is complete and just before being fed into a Giclee printer, would be useful.


3. What’s in the Bag

- 645Z
- D-FA 25mm
- DA 28-45mm
- FA 45-85mm
- FA 80-160mm (occasionally)

- Memory cards (Sandisk Extreme Pro 95mb/s)
- Remotes (like chinese ones better than the Pentax ones)
- Lee 4X6 GND filters and home-made filter holder (only for seascapes)
- Polarizers and ND filters
- A modified inspection mirror (attached near the focus window of a lens)


4. Technical Details

Almost all images are produced from multiple shots with different exposure and focus settings. For those who
are not that comfortable with that notion, here is a simple fact; the human eye doesn’t work like a camera at all.
It constantly captures pieces of the real world and our brains stitch them up and turn into what we call a memory,
an artificial reconstruction and also often incomplete rendition. Each little piece is of different brightness and
placed at a different distance, but our eyes do a tremendous job covering almost over 20 stops of contrast ratio
and infinite depth in a heartbeat. So in order to see the way our eyes do, something has to be done.

The extent of this multi-exposure / multi-focus process depends heavily on the scene. To give you a point of
contact, ‘Echoes of the Silence’ utilizes almost 18 shots, as it represents the worse case scenario for landscape
photography; a large depth of field and a high-contrast backlit lighting condition. On the other hand, ‘A Night with
the Lights’ only(?) needed three mostly to extend the depth of field, as the light was tamable and the nearest
objects were still good tens of feet away. ‘The Highland’ is a single exposure image, that’s what I like about
photographing with a telephoto lens sometimes; the odds are you don’t have to worry too much about depth of field
(well not always, sometimes it gets even worse).

The Sony 51.4MP sensor, just like any high-resolution medium, is prone to optical diffraction, and it becomes
noticeable at any aperture smaller than f/10. If you stop down for increased depth of field, say to f/16, your
effective resolution is not that different than using a 24MP camera (the same thing can be said about large format
film cameras too. If you stop down too much, that negates the very purpose of going big). On the other hand, at
a wider aperture, diffraction may be minimized, but the corners deteriorate quite rapidly due to optical aberrations.
So for most images in this review, the aperture was kept at f/10.

There certainly are some exceptions. When the image includes elements that cover some depth and change
rapidly (waves in seascapes), I resort to smaller apertures. When a sun-star plays a role in the pre-visualized
image, I occasionally stop down to include the desired effect. When I am dealing with stars and the moon, I open
up to let more light in.

I know the newest trend in landscape photography is oriented heavily towards overuse of shadows and Orton
effects to make the images appear more dramatic, but that style has not really spoken to me personally nor is
well suited for print-oriented photography like mine (printers do not handle shadows very well).


5. Photos

Total eight images are presented as examples, and nine different 800px X 800px 100% crops are provided for
each image. All of these images are photographed with the 645Z. Please note that these images are optimized
for canvas prints and therefore sharpened quite aggressively. There are some artifacts because of the level of
sharpening and also the Bayer construction of the sensor, but based on trial and error, we figured it works better
that way for prints.

(1) Echoes of the Silence (2015)
D-FA 25mm / Eastern Sierra, California

(2) Winter Thirst (2015)
D-FA 25mm / Lake Tahoe, Nevada

(3) A Daydream (2015)
A 35mm / Grand Canyon, Arizona

(4) Windows to the Desert Winter (2014)
DA 28-45mm / Canyonlands, Utah

(5) And a River Runs Through (2014)
DA 28-45mm / Yellowstone, Wyoming

(6) The Highland (2014)
FA 80-160mm / Mt. Rainer, Washington

(7) The Grand Stage (2015)
FA 45-85mm / Grand Canyon, Arizona

(8) A Night with the Lights (2015)*
D-FA 25mm / Banff, Alberta
*night photography

To see the 100% crops, just click on any image in the following link.
(I have no intention to promote my website, it just is a better way of getting images organized.)

Hark Lee Photography

To me, the final verdict is quite simple and as predicted. The 645Z is a great camera with amazing DR and low
light capability. The DA 28-45mm is fantastic and outperforms the rest. The D-FA 25mm follows very closely but
it’s got some issues with field curvature and chromatic aberrations (CAs). The FA 45-85mm, FA 80-160mm, and
A 35mm are all great performers, but their days are numbered for any future high MP sensors.


















6. Breakdown

These are things that I learned over the years.

A. High-resolution Photography

(a) The current 51.4MP sensor, when used properly, can make prints with amazing details easily up to 45 X 60
size (about 137.43ppi).
(b) Fully utilizing a 80-100MP sensor will be a real challenge, but it doesn’t hurt to have more (at the expense of
more computing power and storage, but personally I’d rather take the resolution).

B. The 645Z compared with 35mm full frame

(a) The 645 system still holds an edge over any 35mm full frame system in resolution.
(b) With the 51.4MP Sony sensor, the 645Z offers better low light performance than most of the high-resolution
35mm full frame cameras in the market.
(c) The 4:3 ratio works much better for vertically composed images.
(d) The 645 system needs to offer a better ultra-wide angle solution. Even the 25mm feels limited sometimes.
(e) Much bigger and heavier than any 35mm full frame systems.

C. The 645Z compared with the 645D

(a) Much faster operation overall. With the 645D, you need to be patient, but the 645Z feels just right and smooth.
Buffer and writing speed are also greatly improved, enabling responsive interface for the photographer (reviewing
images, checking exposure, histograms, etc.) even in a continuous, high-speed shooting situation (for example,
bracketing five exposures with constantly changing focus under fast-changing light condition)
(b) Vastly improved dynamic range and low light / noise performances.
(c) Shutter / mirror vibrations are reduced significantly, crucial in high-resolution photography.
(d) Articulated screen is a very useful addition for low or high angle shooting.
(e) Live-view is incredibly useful. Especially for accurate focus and exposure.

D. Lenses

(a) D-FA (DA) 25mm

- It is a valuable addition, even when you have the DA 28-45mm. The extra wideness is very useful. Often
I find myself using the 25mm more than the 28-45mm.
- The lens exhibits noticeable field curvature and CAs. Multi-focus shooting can mitigate the field curvature,
and the CAs can be fixed relatively easily in post-processing.
- The lens offers great resolution, but I doubt the corner performance will hold up very well when the sensor
resolution is increased beyond 60-80MP.

(b) DA-28-45mm

- It performs very well with the 645Z, offering fantastic corner-to-corner sharpness through out the entire zoom
range.
- Copy-to-copy variation is quite significant. Please test your lens before purchase. Tested about 3 samples, all
perform differently. The most inconsistency comes from the corners at the wide end (28mm).
- Awfully heavy and big, feels almost over-engineered. SR is almost completely useless for landscape photography.
I can see how Pentax wanted to appeal to the studio crowds with this, but my knees and back are paying the price.

(c) A 35mm

- Early observations (when tested with 645D) indicated that this performs better than the FA 35mm, which showed
more field curvature.
- It still performs very decent with the 645Z, but compared with the DA 28-35mm, high frequency details are subpar.
- Copy-to-copy variation seemed quite minimal, based on 3 different samples I personally tested.
- I don’t see this will make a good lens for the future sensors with higher resolution.
- Still a valuable piece for backpacking trips due to its weight and size.

(d) FA 45-85mm

- Still a fantastic performer. The performance at 45mm is almost comparable to the DA 28-45mm.
- Copy-to-copy variation seemed quite minimal, based on 4 different samples I personally tested.
- Will need to see some updates for 80+MP sensors.
- The best performance-weight ratio of the bunch.

(e) FA 80-160mm

- A great lens at a reasonable price. Overall performance with the 645Z is decent.
- At this focal range, very prone to vibrations. Needs sturdy support.
- Needs to be updated for future 80+MP sensors.


7. Suggestions for Future Development

Here are some things Pentax can do to make it better.

A. 80-100MP sensor

Practically, this will be ultimate resolution for the 645 system. All kinds of logistic challenges to go beyond this;
lenses need to be sharp corner to corner at f/4-5.6 to avoid diffraction and near-to-far focus will require tens of
different layers and extensive post-processing, which means it’s almost practically impossible to utilize this level
of resolution. One way to address this issue is to go with non-bayer, Foveon-type sensor. This will increase the
resolution by a factor of about 1.5 at the same level of diffraction.

B. Ultra-wide angle

Be a prime or a zoom, please make one. Personally, anything close to 18mm (14mm on a 35mm full frame) can
be really useful.

C. Mirrorless

I know it will look funky with the current flange-back distance, but I am up for whatever can shave off a pound.

D. Downsized lenses

Please keep the lenses light. Offer non-SR and not-so-fast variants designed specifically for outdoor photography.
The current system is almost unacceptable for any serious hiker. You will need to add about 20 lbs to the base
weight to carry 645Z + 25mm + 28-45mm + 45-85mm + Gitzo 1 series carbon tripod.

E. Live View

Zooming is fine, but moving to a particular part of the frame is not so smooth and too slow. This considerably slows
down the focusing process in live-view shooting.

F. Automated multi-focus shooting

Multi-focus shooting and focus stacking in the post-process are becoming an essential technique in many
applications. Implement an algorithm to do this. Please allow an option to be used in conjunction with exposure
bracketing; also let the photographer customize what focus range should be bracketed and what not.

G. Focus windows

Additional windows on the sides (or bottom) of lens barrels will be a great addition, so that the photographer has
complete information and control of focus at all times (you can’t check the focus when your camera is higher than
your eye-level). More precise and finer ticks will be very helpful as well. If there is a way to do this electronically
(show a number that precisely displays the current focus distance on the live view feed), it may be better.

H. More custom modes

Three custom modes (U1-U3) are amazingly useful, but one can use one or two more.


8. Acknowledgement

Personally, I am a consumer of practically zero brand loyalty. I take whatever is best for the job. My take is, a
preconceived notion of any company does not really improve my work in any useful way.

Given that, I want to thank Pentax and it’s engineers that have made these great products possible. The 645 system
held up my photography for the past five years, and it saved a number of images that might otherwise have turned
out quite differently. I am an engineer by training and I know how difficult it is to develop these low-volume, high
quality products and keep them afloat. And they have done an excellent job over the years.

Though I still do not call myself a fan (because that kind of rhetoric or mindset often hinders objective assessment),
I sincerely want to thank Pentax for the unconventional devotion to image quality, because it resonates deeply with
the principles I hold as a photographer. And I think I really need to say these things. Because I see something more
than simple business plans in these beautifully strange products.
Forum: Pentax News and Rumors 02-10-2015, 03:48 AM  
CP+ Pentax Interview - Question Suggestions
Posted By harklee
Replies: 188
Views: 18,209
Since nobody's asking anything about the 645 system, I came up with some. Hope it's not too late.

(1) Why did you discontinue the 25mm lens? Any particular reason?

(2) Will there be a replacement for the 25mm? Maybe a super-wide zoom or prime?

(3) The road map shows one standard and one telephoto zoom lenses in the works for the 645 system,
anything else you would like to add?

(4) What sensor resolution (how many MPs) did you have in mind designing the new lenses like 28-45mm and 90mm?
What would be their limits? 60MP? 80MP?

Thanks guys!
Forum: Pentax Medium Format 09-11-2014, 06:13 PM  
DA 28-45mm First Impressions..
Posted By harklee
Replies: 47
Views: 10,503
Digitalis, it takes a little bit of getting used to, and yes, I can see some portrait guys getting annoyed. For me, the camera hardly gets off a tripod, and I do lots of focus stacking where having the focus ring closer comes handy.

---------- Post added 09-11-14 at 06:32 PM ----------



Dear Pål , I am quite a pixel peeper myself, and I tested three different copies of 33-55mm when I first picked up the 645D. I even sent them to the service center in Tokyo to get them individually calibrated. Even after all that, the lenses performed miserably on the corners. And I do not see the point of buying a 50MP camera if the lenses cannot live up to the sensor. I am a rather serious outdoor photographer, and the last thing I want to do is adding more to my already overweight pack. But after testing the new lens, I am almost certain that, to fully utilize the resolving power of the format, the system comes at a price. So as much as I would like to have an ultra-light high-res system (preferably a mirrorless medium format with a shorter flange-back distance and less-retrofocus wide angle lenses), I am afraid that it is not going to happen anytime soon.
Forum: Pentax Medium Format 09-11-2014, 06:05 PM  
DA 28-45mm First Impressions..
Posted By harklee
Replies: 47
Views: 10,503
Guys, here is an update.

So the corner degradation at the wide end (28mm) turns out to be caused by some degree of field curvature, meaning that you can only focus either on the perimeter or on the center of the frame. This is only noticeable at the wide end and is still far better than that of the D-FA 25mm or the FA 35mm. The field curvature can be easily seen by focusing (try manual focus with focus peak on) on different parts of the frame during live view and monitoring the distance meter on the side of the lens. It will change as the focus moves from the center to a corner. However, the live view keeps the aperture wide open, so you are really looking at the field curvature when wide open rather than when stopped down. Regardless, I think the lens is well designed since no wide angle lens is free from some degree of field curvature. I will update the original text accordingly.

The black tapes on the camera are just to prevent it from scratching. I am a landscape guy, and my gear sees some serious use. I just taped some parts of the camera that tend to scratch (based on the years of experience with the 645d).

I tested the lens with a B+W uv filter and a Lee-type adapter ring stacked and they work just fine. Although these are thin wide-angle types so I can't say about regular filters and regular adapter rings.

I will be on a week-long field trip starting tomorrow, so I will post some real-world samples when I am back. Thanks!
Forum: Pentax Medium Format 09-04-2014, 04:59 PM  
DA 28-45mm First Impressions..
Posted By harklee
Replies: 47
Views: 10,503
Added some pics of the lens mounted to the 645Z, and real-life samples will follow in a few weeks. Despite the IQ advantages, I am still torn. The weight and size are quite overwhelming, and I can't see myself hauling this up to the Sierra on a backpacking trip.
Forum: Pentax Medium Format 09-04-2014, 10:33 AM  
DA 28-45mm First Impressions..
Posted By harklee
Replies: 47
Views: 10,503
Received the lens yesterday, unboxed it and ran some tests.
I cannot afford the time to compile the results at the moment,
but these are observations based on thorough testing (an engineer by training).

1. The lens is insanely big, it dwarfs the D-FA 25mm. It looks even bigger than the 645z body.
You will have a hard time finding a space in your bag or taking this up to mountains.
2. For its size, it almost feels light.
3. The build quality is excellent.
4. The front protrudes at the wide end, but not a lot.
5. The hood comes off like conventional lenses.
6. The lens doesn't vignette with a thin B+W screw-in filter and wide angle Lee adapter ring stacked.
7. Optical Performance

- Chromatic aberrations are well controlled (far better than the D-FA 25mm).
- Field curvature is well controlled as well (far less noticeable than the D-FA 25mm or FA 25mm).
- At the wide end (28mm), it suffers from mild filed curvature, I recommend carefully taking multiple shots with slightly different focus settings and studying them.
- The lens design appears to be optimized at around 35mm.
- Superb image quality from 30 to 45mm.
- At around 35mm, even f/5.6 seems to offer superb corner to corner sharpness.
- Other than around 35mm, the lens is sharp from corner to corner from f/7.1-f/9.0.
- The D-FA 25mm is wider and sharper than the zoom at the wide end (28mm), but it also has more chromatic aberrations and noticeable field curvature.
- The A 35mm comes close, but the zoom outperforms the prime in every aspect.
- The FA 45-85mm has a narrower view angle than the DA 28-45mm at 45mm, and the DA 28-45mm offers almost identical image quality.

To sum up, the DA 28-45mm delivers great IQ in most of its focal range, but does not replace the D-FA or DA 25mm.
It outperforms both A 35mm and FA 35mm by a margin, and offers similar or slightly better IQ than the FA 45-85mm.
Kudos to Pentax for producing a great piece of glass, but the weight and size will limit its usage and put your tripods and
bags to the test.


Additional pics : when mounted







Forum: Pentax Medium Format 08-06-2014, 02:36 PM  
New 28-45 Sample images are up
Posted By harklee
Replies: 12
Views: 2,015
While this appears to be executed more professionally (combination of panning and interesting lighting), is this really a good image to showcase the optical performance? Jeez, Ricoh, you engineered a 3.2 lbs heavy duty WA zoom lens most likely optimized for corner to corner sharpness. What images do you think will do the job to convince potential buyers? Well, I'm done complaining; I will post some pics when I get my hands on it.
Forum: Pentax Medium Format 08-05-2014, 08:32 PM  
First Look Video: HD PENTAX DA 645 28-45mm F4.5 ED AW SR
Posted By harklee
Replies: 10
Views: 2,709
Holy smoke, that is INSANELY BIG. There is no way (unless I can shed 3 lbs without losing the muscles) that thing finds a place in my pack. I will first run some tests to see how much of IQ improvement we are talking about over the A or FA 35mm.
Forum: Pentax Medium Format 08-05-2014, 03:56 PM  
New 28-45 Sample images are up
Posted By harklee
Replies: 12
Views: 2,015
Seriously, these are the sample images you put out to promote a $5000 lens? I like Pentax as a company that offers what others dare not, but they need to hire a proper professional that can produce quality images.
Forum: Pentax Medium Format 08-04-2014, 10:28 AM  
Pentax HD PENTAX-DA645 28-45mm f/4.5 ED AW SR Lens listed on B&H
Posted By harklee
Replies: 20
Views: 3,409
That's weird. The link is no longer active. I guess B&H realized that they broke the embargo and took it down. To me, the weight is a big turn-off since I mostly do landscapes and often go on strenuous hikes in the Sierra. I will be tempted only If they can keep the price reasonable (under $5000) and offer substantially improved IQ over the A and FA 35mm, which are already pretty good lenses.
Forum: Pentax Medium Format 07-19-2014, 07:25 AM  
645D vs. A7R
Posted By harklee
Replies: 109
Views: 19,556
Royce, I couldn't agree more with what you said. My experiences with 645D, 645Z, and D800E have been more or less the same. The D800, D800E, and most likely D810 (judging from the specs) offer shooting options that are, quite frankly, downright weird. The bracketing spacing (exposure difference between shots) can be set only up to 1 EV, and you have to take 5 shots to cover 4EV, which gets quite annoying in fast-changing light conditions. Especially with 14.5 stops of DR the Sony sensor offers, I really don't see the point of having only 1 stop difference between shots. Customization of the bracketing order is also limited, at least compared to the D or Z, and this can easily lead to frustration in the field. The dedicated buttons on 645D have served me well over the years and they can make a huge difference in getting the shot.
Forum: Pentax Medium Format 07-16-2014, 07:23 AM  
D-FA 25mm f/4 discontinued
Posted By harklee
Replies: 22
Views: 5,393
My two cents is they probably are planning to not go full frame. The very reason for the introduction of the DA 25mm was to reduce the manufacturing cost (and improve the optical performance a little), and they simply do not want to keep two production lines, which means additional cost. I strongly suspect that the new wide angle zoom will also be DA, and they will release the DA 25mm in the Japanese market soon.
Forum: Pentax Medium Format 03-06-2012, 10:48 AM  
Good news, some of my 645d images now on www.CNN.com
Posted By harklee
Replies: 27
Views: 4,175
@gurtch
Thank you so much, David, but how I am supposed to believe your words after seeing your photos? :) Keep up the great work.

@Bigvern1263
Congratulations, I am sure you will be happy with the 645d, the past 1.5 years with it has been a blast for me.

@tcom
What a set of fantastic images you got there, Dominique, I also started reading your articles on the IMPress, fantastic work.

@Confused
Obviously you have more than enough skills to call yourself an 'expert' at image retouching. Interestingly that version looks a lot like
what I took with 'a bit too strong' GND filter. The reason for that was to overexpose the shadows for better details and put them back
into the proper 'zone' later in the processing. I usually try very hard to remember the scene and its overall 'tonal distribution' while
taking shots and that's why decided to darken the foreground based on my memories. But I totally understand what you did there
and why many people actually prefer your version. :)

@Clicker, RonHendriks1966, Eduard Kraft, GregK8
Thanks a lot for the comments, guys, I really appreciate each and every one of them.
Forum: Pentax Medium Format 02-24-2012, 08:07 PM  
Good news, some of my 645d images now on www.CNN.com
Posted By harklee
Replies: 27
Views: 4,175
Thanks a lot for the comments, guys, much appreciated.

@jsherman999
Thanks, I may have some updates and new information, will post in a few weeks.

@abieleck
Graduated NDs from Lee Filters are used on most of the high contrast shots, also a hint of manual blending for the small patches of blown out highlights.
No HDR or Exposure Fusion. I also used focus stacking for some of them for extended DOF while keeping the aperture below f/11-13 (to minimize
diffraction). Basic dodging and burning, colors are all natural.

@v5planet
I'm sure I mentioned that in the interview but didn't expect that it would come out that simple and painful. LOL, well, we've all been there. :)

@loco
I was introduced to CNN Korea by a friend of mine while I was visiting there and did a little project with www.CNNGO.com.
Basically they were looking for a photographer to do some gallery-type articles.

Gallery: How to take stunning city photographs | CNNGo.com

They seemed satisfied with the results and contacted me this time for a short article / interview. :)
Forum: Pentax Medium Format 02-24-2012, 12:40 PM  
Good news, some of my 645d images now on www.CNN.com
Posted By harklee
Replies: 27
Views: 4,175
Hi, Fellow Pentaxians,

I got some of my images published on the travel section of the CNN website (international edition : Travel News - Headlines, Stories and Video from CNN.com International)
titled 'how to take stunning landscape photographs', although the title and content of the article are not quite what I envisioned.
It's a short article based on an even shorter interview with the editor, and I asked for a revision so don't get too upset about
the poor content. :)

The gallery contains 12 photos, 9 of which are taken with 645d. I wanted to include newest work but they asked 2:3 aspect ratio
images for the vertical, so I ended up using some 5d II images.

1, 6, 8, 11 (see below) are taken with the D-FA 25mm, which I think is a fantastic piece of glass (still not quite convinced about the
price tag). Sorry about my long absense and I will write back with newest thoughts on the past 1.5 years with 645d. Thank you.



'The Light of Sierra' (Saddlebag Lake, Yosemite National Park, California, 2011)




'A Fairy' (Grand Canyon National Park, Arizona)




'A Lucid Dream' (Rodeo Cove, Marin, California)




'Valley of the Fall' (Lundy Canyon, Inyo National Forest, California)
Forum: Pentax Medium Format 07-21-2011, 04:05 PM  
Pentax D-FA 645 25mm f/4 AL (IF) AW Review
Posted By harklee
Replies: 36
Views: 22,106
You are very welcome, Laurence, I hope it works out for you. FYI, I use the Leica Disto D2 and it doesn't work for anything farther than 200ft. It also doesn't work when the ambient light is too bright or on a reflective surface. : )



Mike,

You are absolutly right about the alignment issues, when you have grasses or flowers that do not have fixed positions, they could be a problem. But then again, you still have that issue even for a single exposure shot, since during the golden hour we are dealing with an exposure at least a second long. So the best way to go about it is get the right timing and take mutiple shots as quickly as possible while things are not moving. Also try to carefully partition your shots so that you won't have moving objects near the seams. : )

About the DOF question, the depth of field is directly related to the circle of confusion you allow, and therefore a very subjective quantity. That's why you cannot simply go hyperfocal and believe everything from the half the hyperfocal distance to infinity is 'sharp'. As I mentioned above, take some shots with different focus settings and take a look at 100%, so that you know what kind of pixel sharpness you are talking about. Also the sharpness issues can occur from lens defects such as field curvature (which has been an issue for FA 35mm), so I encourage this kind of first-hand tests.


Thanks for the kind words, Joe, I really appreciate the comment.


Thanks for sharing Zygonyx, that's a lot of useful information!


Great sample, Tuco, I will try that myself too. Thanks for sharing. : )
Forum: Pentax Medium Format 07-10-2011, 10:49 AM  
Pentax D-FA 645 25mm f/4 AL (IF) AW Review
Posted By harklee
Replies: 36
Views: 22,106
Laurence,

Here is a rough write-up of the process,

First, run a series of tests on the lens you would like to use.

Tape a small patch of tick marks on your lens (as shown in the pic) so that you will be able to remember and go back to a specific focus setting for your lens.



Choose a place with noticeable textures or objects in the foreground so that you can identify if any spot is in or out of focus. Set up a few targets (or just pick some objects in the foreground), measure and remember their distances from the camera using a long tape measure or laser distance meter.

An example of laser distance meter :
http://www.google.com/products/catalog?q=leica+distance+meter&hl=en&rls=com....d=0CJ8BEPMCMAA#

Now take a number of shots with different focus settings (at different tick marks) and analyze them to figure out the DOF of each shot (each setting). Since DOF is something somewhat subjective to the photographer himself and viewers, you have to establish your own standards.

In the field, carry a laser distance meter or try ballparking the distance to your nearest foreground and also estimate the distance to the farest background, which will give you the necessary DOF for that specific shot. Based on your knowledge, take multiple shots that will cover the required DOF.

Load the images into one Photoshop file, choose the one with background (or most coverage) as your background layer. Now you have multiple layers in your file, select (ctrl+click in the layer window) them all (or one pair of a foreground layer and the background layer at a time), go to 'Edit' -> 'Auto Align Layers' -> 'Auto'. This will resize your foreground layer(s) to fit the background layer (if the auto align doesn't work, you can also manually align it).

Now you can use a conventional layer mask to seletively (manual) blend, or go to 'Edit' -> 'Auto Blend Layers' -> 'Auto' to automatically blend them. Please keep in mind that the foreground layers are always a tad smaller in size than the background layer, so make sure to crop the photo properly (in case you are using the auto blending, you may want to do this right before merging to avoid blurry edges).

Some folks seem to use specialized focus-stack softwares, but I don't have any experiences them. Hope this helps and let me know if you have any questions. Thanks!

- Hark
Forum: Pentax Medium Format 06-30-2011, 01:39 PM  
Pentax D-FA 645 25mm f/4 AL (IF) AW Review
Posted By harklee
Replies: 36
Views: 22,106
B&H says July on the website, so it should be available soon. :)
Forum: Pentax Medium Format 06-28-2011, 10:51 AM  
Pentax D-FA 645 25mm f/4 AL (IF) AW Review
Posted By harklee
Replies: 36
Views: 22,106
Here are two more sample pics from a weekend trip to Yosemite. Both pics were taken with D-FA 25mm and the weather was almost too clear for landscape shots.


Tioga Lake, Yosemite National Park, California



Dog Lake, Yosemite National Park, California
Forum: Pentax Medium Format 06-28-2011, 09:04 AM  
Pentax D-FA 645 25mm f/4 AL (IF) AW Review
Posted By harklee
Replies: 36
Views: 22,106
Thank you all for the comments.


Thanks Adam, I will go ahead and type in the numbers. : )


Tom, that's strange. The files download fine on my computer, you may try right-click and 'save as'? Or you can simply try changing the extension to PEF and try opening them with the newest verion of ACR or Pentax RAW converter.


Digitalis, thanks for the detailed comment, yeah, Nikon 14-24mm and Canon 24mm II have really changed my perception of retro-focus type wide angle lenses and I just thought it would be an interesting comparison. : )


Thanks for the compliment, Yamanobori, that was taken with A 645 35mm f/3.5.


DandA, I think A 35mm has a slight edge over FA 35mm (at least with the current sensor size of 645d), and D-FA 25mm beat them both in resolultion. If it wasn't for CAs and price, I would give this lens a 10.


Zygonyx, that was taken with the FA 45-85mm zoom. : )
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