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Pentax 645D Questions

iiiNelson

Well-known member
So I've been debating selling my M9-P and maybe the 35 Summicron ASPH (while keeping my other lenses in case I want to re-enter the Leica world at some point) the last few months and adding a MF system since I really really like my A7 and A7r combo so much. That will probably cover the cost of a Pentax 645D and maybe a lens or 2 at current prices. I've read and researched through the forums on the camera so I have somewhat of a general idea of what to expect from the camera. I do have a question regarding lenses. How hard is it to find good copies used and how hard is it to purchase them new from overseas sellers? What about the "hidden costs" that you often find out about after the sale sometimes? Any surprises? Any recommended accessories? I know the new one is coming out but I really like the look of the current CCD (but if some great samples come out that blow me away prior to my purchase then maybe I'll swing the extra coin for it.)

I hope to start with the Pentax 645D + 55/2.8 + 120/4 Macro (if I can find one in like new to excellent condition) If I make the ultimate decision to go this route. Oh yeah and I'd prefer to work with AF lenses but I'm not completely opposed to MF if that's all that's available.
 

tsjanik

Well-known member
It's not difficult to find good used lenses or order new ones from Japan or Europe. I have way too many lenses ranging from 35mm to 600mm; other than the 600mm, none of them is hard to find. I would suggest you add the 35mm A to your lens list. A good copy will cost about $400 and most prefer the manual A version to the auto-focus FA. I had both and sold the FA version. I've had the camera over three years, no surprises other than how long the battery charge lasts (a long time). The write speed is slow, so if you're in hurry and want to see the image on the lcd, you may find that frustrating.
 

Charles Wood

New member
Ditto what tsjanik posted. I was fortunate to own a pretty complete selection of lenses from my Pentax 645N film days. The 35mm is especially outstanding. KEH is a source of used lenses and they offer a liberal return policy if the lens doesn't meet your expectations.

I've compared images from my 645D against those from the D800/300e. A friend owns a 645D and a Sony a7r. We both prefer the images from the 645D, other pros/cons notwithstanding.

Pentax service is still lagging badly in this country. Ricoh really needs to get on top of that situation. OTOH, I've had no problems in 2.5 years with my 645D and for the current selling price of $6495.00, a serious user could buy a second body for backup and still be into MFD for less than the entry cost into other systems...assuming of course that the 645D meets your needs and shooting style.
 

iiiNelson

Well-known member
Thanks for the replies and the write speed rob ably wouldn't bother me much if at all. I'm not a heavy chimper at all and I'm somewhat used to shooting slower from owning a pair of M9's as my primary cameras for the last 4 years. I guess I need to take a closer look at what's available on the used market and also another (read: closer look at the competition as well.)
 

D&A

Well-known member
All of the above posts mirror my experiences with the 645D and lenses ranging from 35mm to 600mm. Although I am partial to the Af lenses simply due to my own personal requirements, many of the manual focus ones have the same optical formula,, although not all, and can be had for significantly less in many cases.

Having used and tested the manual focus and AF versions of the 35mm f3.5 lenses, there are differences between the two and I found advantages and disadvantages for each optically. Both though are exceptionally good.

With regards to the AF lenses, there are though significant differences in performance from sample to sample, even brand new ones out of the box. I found this out by testing many samples of a given lens and not always could AF fine tuning in the body itself overcome these differences. The reason is these lenses were for the most part made during the film era and as such were loosely adjusted (adequately) for that medium...much like some older pre digital Leica lenses that were made during the film era. Many of those had to be readjusted to get their expected performance level on digital. Here on Getdpi I posted a comprehensive lens test of most all of the Pentax Af 645 lenses when used on the 645D (multiple samples of most). I don't have the link handy but maybe someone else does. It will give you a good idea of what to expect.

As mentioned, the write speeds of the 645D is its weakest point due to a slow processor, but in most cases it's not a hindrance. Reliability as expressed by others is simply fantastic. The look of the output from it's CCD is lovely.

Keep us posted.

Dave (D&A)
 

iiiNelson

Well-known member
All of the above posts mirror my experiences with the 645D and lenses ranging from 35mm to 600mm. Although I am partial to the Af lenses simply due to my own personal requirements, many of the manual focus ones have the same optical formula,, although not all, and can be had for significantly less in many cases.

Having used and tested the manual focus and AF versions of the 35mm f3.5 lenses, there are differences between the two and I found advantages and disadvantages for each optically. Both though are exceptionally good.

With regards to the AF lenses, there are though significant differences in performance from sample to sample, even brand new ones out of the box. I found this out by testing many samples of a given lens and not always could AF fine tuning in the body itself overcome these differences. The reason is these lenses were for the most part made during the film era and as such were loosely adjusted (adequately) for that medium...much like some older pre digital Leica lenses that were made during the film era. Many of those had to be readjusted to get their expected performance level on digital. Here on Getdpi I posted a comprehensive lens test of most all of the Pentax Af 645 lenses when used on the 645D (multiple samples of most). I don't have the link handy but maybe someone else does. It will give you a good idea of what to expect.

As mentioned, the write speeds of the 645D is its weakest point due to a slow processor, but in most cases it's not a hindrance. Reliability as expressed by others is simply fantastic. The look of the output from it's CCD is lovely.

Keep us posted.

Dave (D&A)
Thanks for your reply as well. I did read your lens review when you first posted it and again earlier today. I know it was a lot of work but it definitely saves people a lot of time from scanning the internet only to come to the exact same conclusion that you did pretty much.

The price is extremely attractive right now being the same exact price as the D4s (not that I want one of those) and it's sort of a sweet spot for those that want to dip their feet in the water. The newer lenses are as expensive as the lenses from other MF companies but I guess thats to be expected with new/ updated designs. I guess my only REAL reservation is the dealer and service network post warranty but many people have had their units for 3+ years without issue. The advent of the new CMOS version is also attractive for a second body provide the lenses can keep up and the IQ of that body lives up to the potential (which I have little doubts about if Sony is the manufacturer.)
 

D&A

Well-known member
I'll add a few additional comments:

I'm not saying the newly released lenses aren't welcomed (they certainly are)... but the legacy lenses for the most part are exceptionally good and in some cases hold their own against their newer counterparts when overlapping focal lengths are compared. That's what makes this system a relative bargain...the legacy lenses.

Reliability is a big plus and although anything can go wrong with any given camera, there have been very few reports of issues or breakdowns. It's careful lens selection that in my option that is the key to this system, especially that we're all dealing with many lenses designed and made during the film era, and requirements were quite different. Once that's done, you'll achieve some remarkable results. One think to keep in mind though with many of these lenses say as compared to the Leica S system, is that you will have to stop down considerably to achieve most of the performance you're looking for whereas with the Leica S, you can shoot with many of their lenses wide open.

Dave (D&A)
 

Pics2

New member
I'm also thinkig about Pentax 645D. I heard few people at Pentax forum complaining about centerfold issue. Have you guys experienced it, is it a rare problem?
 

Ken_R

New member
I'm also thinkig about Pentax 645D. I heard few people at Pentax forum complaining about centerfold issue. Have you guys experienced it, is it a rare problem?
I had a 645D for a few weeks and never saw anything like that. Loved the camera.

Did not love the lenses. They are good at f11. The 35mm FA (AF) is not good for landscape/architecture due to softness in areas of the image (even at f11) when focused at far distances. I had one and sold it. Up close it is a very good lens. The 35mm A (Manual Focus) was awesome for landscape at f11-f16. If you find a good one for sale snatch it asap. Clean samples are somewhat hard to find.

The new 55mm lens is good optically but feels somewhat cheap for a $1200 lens. Same with the 90mm lens. Great lens but IMHO overpriced at $4500.
 

D&A

Well-known member
There have been some reports of the center fold issue (stitching of both half of the sensor), but for the # of cameras sold, I believe the numbers are relatively low.

The FA 35mm does have considerable field curvature which is evident at infinity, but is a exceptionally good lens optically and has some positive attributes when compared to the manual focus version of that lens. It depends what ones priorities are in terms of what they shoot. Both excellent lenses with different priorities and I've employed both in professional shoots that required edge to edge sharpness for poster sized prints.

As I pointed out, many of the lenses do have to be stopped down considerably for best performance which is in contrast to the Leica "S" system.

Dave (D&A)
 

bensonga

Well-known member
Hmmm.....I have the 55mm SDM lens too and I would not have described it as feeling somewhat cheaply made. I think it feels more solidly made than a few of the 645 FA lenses I own. It's the only "affordable" SDM lens in the lineup.

If anyone is looking for a 25mm SDM lens in excellent condition (EX+ or LN-), I have a friend who recently sold his Pentax 645D and lenses....this is the only lens he has left. He's asking $3500. He is the original owner and I can vouch for the fact that he takes excellent care of his gear.

Gary
 

iiiNelson

Well-known member
Hmmm.....I have the 55mm SDM lens too and I would not have described it as feeling somewhat cheaply made. I think it feels more solidly made than a few of the 645 FA lenses I own. It's the only "affordable" SDM lens in the lineup.

If anyone is looking for a 25mm SDM lens in excellent condition (EX+ or LN-), I have a friend who recently sold his Pentax 645D and lenses....this is the only lens he has left. He's asking $3500.

Gary
If I sell off my Leica M9/ 35 Cron ASPH, make a final decision on the Pentax 645D, and he still has the 25 I would probably be interested. It's definitely on my list of lenses to own as I prefer something in the 18-24 range above something in the 28mm range(one of my most hated focal lengths on a prime or zoom that starts in that range) like the 35/2.8 gives (when speaking in 35mm FF terms.)
 

iiiNelson

Well-known member
There have been some reports of the center fold issue (stitching of both half of the sensor), but for the # of cameras sold, I believe the numbers are relatively low.

The FA 35mm does have considerable field curvature which is evident at infinity, but is a exceptionally good lens optically and has some positive attributes when compared to the manual focus version of that lens. It depends what ones priorities are in terms of what they shoot. Both excellent lenses with different priorities and I've employed both in professional shoots that required edge to edge sharpness for poster sized prints.

As I pointed out, many of the lenses do have to be stopped down considerably for best performance which is in contrast to the Leica "S" system.

Dave (D&A)
I think that's a thing I'd have to get used to if I switch... Not being able to get great results even wide open. It's almost one of those thing where you're like why bother making a lens f/2.8 when you don't get acceptable results until f/4-8? Just make it a f/4-5.6, make it for a reasonable price, and call it a day.
 

tsjanik

Well-known member
I think that's a thing I'd have to get used to if I switch... Not being able to get great results even wide open. It's almost one of those thing where you're like why bother making a lens f/2.8 when you don't get acceptable results until f/4-8? Just make it a f/4-5.6, make it for a reasonable price, and call it a day.
Some of the lenses are quite sharp wide open; they all improve by stopping down, but not many lenses don't. I sometimes suspect that some reported softness at wide aperatures may be focus issues.
 

ondebanks

Member
There have been some reports of the center fold issue (stitching of both half of the sensor)
That centerfold issue is not caused by stitching of the sensor; it's caused by splitting the readout through two different registers, one left and one right, leading to separate outputs with their own slightly different gain and noise characteristics. This trades off frame uniformity for frame rate.



"Each remaining line (row) of charge is first transported from the VCCD to a dual parallel split horizontal register (HCCD)...Readout of each line in the HCCD is always split at the middle and, thus, either two or four outputs are used. Left (or right) outputs carry image content from pixels in the left (or right) columns of the VCCD...Left and right HCCDs are electrically isolated from each other except for the common transfer gate (XG)."

Ray
 

D&A

Well-known member
Some of the lenses are quite sharp wide open; they all improve by stopping down, but not many lenses don't. I sometimes suspect that some reported softness at wide aperatures may be focus issues.
I didn't mean to imply that many of the Pentax 645 lenses couldn't be shot wide open or a stop down from max. aperture....but one can readily seen the marked improvement in many of these lenses by stopping down, especially if one needs to achieve edge to edge sharpness. The other consideration is what one intends to do with the output. If its for large format printing at larger sizes, then many of the legacy lenses do benefit from stopping down a fair amount.

One thing is for certain...in my lens testing, I found with almost all 645 lenses, that carfule Af fine tuning them on the 645D is mandatory and one can see the remarkable difference as a result.

Dave (D&A)
 

tsjanik

Well-known member
Dave, my comment was not directed at you. I've seen a number of posts from people who've had little experience with the camera and lenses but proclaim that the lenses are "soft".

Tom
 

Jamgolf

Member
I'll share a few thoughts as I bought a pre-owned Pentax 645D about 3 months ago replacing my D800.
I am a hobbyist not a pro, so keep that in mind if you draw any conclusions from my input.

CAMERA: I am happy with Pentax 645D. I find its color output very pleasing. Like yourself, I am a Leica M9 user and I feel the color fidelity is similarly pleasant. Resolution is great but it needs a very sturdy tripod. The results, when used correctly & deliberately are very rewarding (to me).

PENTAX LENSES:
As far as lenses are concerned I purchased the following lenses:

55mm AW: I bought it with the camera, sold it but then re-purchased it. I like it. I think its under-rated.
90mm AW: Excellent performer. Shake reduction is handy. I think its over priced. I found a used one.
25mm AW: I have returned 2 copies, one bought from B&H and another from Japan. One FA the other D FA.
Sharp but shows a LOT of purple fringing and chromatic abberation in strongly backlit subjects.

120mm FA: My copy was nothing special. Had to stop it down considerably. Sold it.
150mm FA: Nice but nothing special. Still have it. Probably will sell it.
300mm FA: My copy was pretty good. I found it difficult to use even on a stable tripod. Sold it.


ZEISS LENSES:
I've converted & used a lot of Leica-R and Zeiss lenses with Nikon D800/D700 and I loved them (and miss them). In that spirit, I decided to explore some alternative lenses for the Pentax 645D. After a lot of reading and research I got these...

Hasselblad/Zeiss 40mm CFE IF: Wow. I feel its a lens that does justice to the sensor. Excellent resolution.
Hasselblad/Zeiss 100mm CFi: Very very nice. Optically very similar (I think better than) Pentax 90mm AW.
Hasselblad/Zeiss 250 Superachromat: Wow. What fine resolution and color fidelity. Awesome.


CONCLUSION:
I am very glad to have purchased 645D and even more glad that it lead to the purchase of 40mm CFE IF and 250 Superachromat. I think they are gems and I was lucky enough to buy them for very close to the price of a new 25mm AW.
Its been a fun few weeks of buying/trying/selling. In general I found the older Pentax lenses not really that great (my opinion).

I think one of the prime reasons for getting a medium format digital camera is to achieve the resolution, sharpness and the-look that is generally attributed to medium format. I feel matching high performing lenses to high quality sensors is a step toward achieving that goal.

I hope you (or someone else) will find this helpful.
Good luck with your decision.
Cheers !
 
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D&A

Well-known member
Hi Jamgolf,
Interesting observations and appreciate your sharing them. I too believe the full potential of the 645D hasn't always been fully realized with the use of many of the legacy lenses.

I've had the opportunity to shoot with the 25mm and also found at times excessively high levels of CA, especially with strongly backlit subjects. I assume you found little difference between the D FA and DA samples your tried? Something tells me the only difference between the two was Pentax extending the hood over the front element in the DA version. Not even sure if additional coatings were employed. Thanks.

Dave (D&A)
 

Jamgolf

Member
Dave >>>> I assume you found little difference between the D FA and DA samples your tried?

I did not get a chance to test the two 25mm versions side by side or in similar lighting conditions so I can't really say definitively.
If I rely on my memory and impressions, I would say that D FA (older-model from Japan) showed less CA but more flare.
DA (newer-model from USA) showed more CA but seemed flare proof.

Please note, I did not keep these lenses for an extended period of time, just did some quick tests to make up my mind.
 
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