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Forum: Pentax Medium Format 02-20-2011, 10:16 PM  
645D and image quality
Posted By VoltMan
Replies: 16
Views: 5,738
Film or Digital IQ aside it would be interesting to see the full uncropped 67 frame as well to compare with the 645D full frame in terms of coverage angle to judge the relative impact on an overall print. My point being that a 67 w/55mm's equivalent on the 645D is roughly a 35mm, and conversely the 645D w/55mm's equivalent would be roughly a 90mm on the 67. (??)
Forum: Pentax Medium Format 02-18-2011, 08:39 AM  
Digitizing Medium Format - Canon 8800f [vs] DIY Copy Stand
Posted By VoltMan
Replies: 9
Views: 4,432
2nd that - it is pretty cool! I like unconventional approaches - this would be great for web output. Curious though if large prints were done with both files and compared what would the output look like? It seems intuitive the scanned files could print higher resolution than the K-x (even with raw)??
Forum: Pentax Medium Format 02-15-2011, 04:49 PM  
New lens roadmap for 645D
Posted By VoltMan
Replies: 42
Views: 8,353
Looking at my adapter - I don't think there is sufficient clearance for a large amount of tilt but shift I can see as a possiblity when comparing to another shift lens...
Forum: Pentax Medium Format 02-12-2011, 09:32 PM  
Travelling with medium format gear
Posted By VoltMan
Replies: 26
Views: 6,194
Second that. Though no experience with film I've on 2 occasions been called from the gate to security for checked baggage containing equipment which they found suspicious in checked luggage and wanted explanations for - both times due to the internal characteristics of a integrated circuit component on test equipment I was carrying. If they have machines strong enough to pass through the 1mm zinc cladding of that component I wouldn't want to put film through it at all.
Forum: Pentax Medium Format 02-10-2011, 11:07 PM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Steven,

P645DF body aside (and I agree it doesn't "feel" well) I had good results from the 28/4.5 for urban exterior and street shots, granted a bit soft around the edges as you've noted - however I note that's FF coverage on a FF sensor. I won't argue the HCD either (see my earlier comparison post). What frustrates me is that in going with the 645D I'm willing to compromise resolution for a DSLR MF camera, but by gosh I'd expect to see a stellar lens for it at that price point - something that differentiates itself to justify buying it, especially given a 33x44 sensor.

Like you I think the 645D body itself is superb - the controls and everything about it make it a perfect (yet quirky) "on the go" platform, but its held back by its optics. For right now it does what I want, its just I'd hoped to get more out of it.

I'm ordering the IQ180 as an upgrade for the 65+ so for wide angle work I'm going to test the Hartblei Cam in May using a Canon 24mm TS and Hartblei/Zeiss 40/4 TS which both look promising from the files I've been shown. The new IQ interface is also a big leap ahead of the P series from what they've shown, and though I'm skeptical about the usability of its Live View function - if that function even works out at only 1fps it'd be perfect for my purposes. The Hartblei also takes the Zeiss T/S line which I drool over as well ..
Forum: Pentax Medium Format 02-10-2011, 05:57 PM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Nice job cleaning up that file, and hopefully output from raw will significantly improve. Yet I'm still dismayed they would release a lens that produced images like that (even JPEG) without going the extra mile to clean up the design. Perhaps they've said somewhere it will provide FF coverage - its not on their specs page - but my point is a 645D can't use that coverage and if it did the CA would be as bad and probably much worse on the outer reaches of that coverage.

I've read the 38 Biogon design was ground-breaking - in 1954 (I wasn't even born yet), and continued to be so for something like 50 years, even with its shortcomings. Its simply amazing something like that could even arise from the ashes of WWII. But this is 2011 - some 57 years later, and I had much higher expectations from Pentax. I was actually hoping they could lower my kit costs or improve performance as well - that didn't happen.

With all that negativity you might assume I'm not happy with the 645D as a system - but not so - it provides a lot of practical advantages for me, but just not in wide angle applications, and I don't find the 25mm to be a good investment as I have other options which other people may not have.
Forum: Pentax Medium Format 02-10-2011, 09:19 AM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Actually I've been looking intensely today at files from a Mamiya 28/4.5 - and in the frame area equivalent to the 25/4 from Pentax there is substantially less CA. On top of that it has more coverage (102 degrees) which gives me more scene in the frame. As an added bonus I get 80MP with ~12.5 stops of DR to work with.

To say CA and distortion isn't an issue in the digital era - well I guess if you're used to making compromises up front in the workflow its okay - in the end to me its like polishing a terd. Else if you have expectations of making the best images possible you have to rethink that approach. Not to mention the dozens of folks shooting B/W film here are going to have a really hard time compensating in CS I would think.

These claims of "the widest MF lens" to me are ridiculous in comparison to the Phase/Mamiya or Hasselblad. You can simply make a much higher resolution, wider angle digital photograph with a Phase/Mamiya platform with much less distortion, that will produce large prints far superior in detail and image quality. Given the costs of these lenses one would have expected them to be on rough par. From what Pentax has shown in the last several days it makes the choice v. easy for me not to get the 25mm, which means my 645D will remain in the role I bought it for - an inexpensive knock around MF digital with reasonable auto-focus. I was actually going to CP+ to look at this lens tomorrow (Friday) but now to be honest its not worth the 40 minute train ride.
Forum: Pentax Medium Format 02-10-2011, 08:05 AM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Anything can be made to look better in CS5 or post - but lens IQ/distortion "is what it is" out of the camera - ask the film folks ;)


Clearly those aren't JPEG artifacts and are simply due to lens distortion (high CA) only seen in the outer ~1/3 of the frames and is clearly visible on a 30" monitor at about 24" viewing distance:



Given the price, the 95 angle of coverage on a 645D 33x44mm sensor (same as HCD 28@37x49 and 7 *less* than a Phase/Mamiya 28 which is 102@40x53) and the certainty that the CA will increase even more on a full frame (film or digital) I'm not impressed at all. For all the hoopla of how this lens is "the widest for medium format" and designed for "landscape" if you look at the real facts its 3rd place in medium format digital SLR wides way behind what Phase/Mamiya & Hasselblad's platforms offer:

Make----/----Coverage @ max resolution----/----35mm Equiv.----/----My impressions
Phase/Mamiya 28/4.5- 102 coverage for 40x53 (80MP) - 17mm- sharp/low CA (~$4500)
Hasselblad 28/4 - 95 coverage for 37x49 (60MP) - 22mm - v. sharp/v. low CA (~$4500)
Pentax 25/4 - 95 coverage for 33x44 (40MP) - 19.5mm - looks sharp?/moderate-high CA? (~$4900)

(Note I'm a resolution bigot but arguably I could concede the HCD could be #1 as well for its sharpness and comparative lack of CA even given its angle of view)

So it looks to me the above is the "digital MF SLR wide angle state of the union" for quite a few years to come unless Phase/Mamiya/Hasselblad up the anty further. It will be interesting to see what comes out on Velvia or Acros etc.. Its also not encouraging that Pentax hasn't released the MTFs, nor coverage specs for 645 film/FF digital I might add.

In short their 25mm isn't a game changer but more like a loser to me. Which is a shame as I was holding out hope... and only time (which I don't have) and a Pentax full frame sensor (which they won't make for years to come) can prove me wrong.
Forum: Pentax Medium Format 02-10-2011, 02:10 AM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Well I guess all I can say is they've certainly picked pretty good subjects to put it to test by looking in the extreme corners - no pixel peeping required. At least the fringing is consistent :D
Forum: Pentax Medium Format 02-09-2011, 11:31 PM  
New lens roadmap for 645D
Posted By VoltMan
Replies: 42
Views: 8,353
I wouldn't underestimate the Chinese making "similar, compatible" lenses - apparently they already have a manual 645 that takes Pentax mount lenses, and a digital conversion for it as well. So if you have patience, latitude for Diana quality lenses, and no need for AF I bet you'll have an option soon, otherwise I'd just spend my money on A series lenses :)





None that I know of; however there are some unique lenses for the P67 which can adapt to the 645, e.g. Nikkor P.C. 1200mm/f11, and the awesome LensBaby 3G MF!
Forum: Pentax Medium Format 02-09-2011, 07:28 AM  
Love My 645 But...
Posted By VoltMan
Replies: 16
Views: 3,374
Topaz - as background I have 3 RZIId bodies and every lens ever released + all the accessories. I love that system for what it delivers me indoors and *occasionally* out of doors.

However if I were in a position of no digital SLR and 1 645 and 1 RZ I'd still dump the RZ in a heartbeat to get into a digital platform (no matter if it was entry level) and retain the 645 for film. Unless you're reliant on the RZ for a living (highly doubt it as film costs would be a killer) its really a no brainer.Moving to digital in so many ways improves your photography and preserves your memories, while time and opportunities are irreplaceable. Spring is coming I might add...
Forum: Pentax Medium Format 02-09-2011, 02:16 AM  
FA*300mm F4 on 645d
Posted By VoltMan
Replies: 22
Views: 4,758
I have the 405 - "beyond" is correct - I'm sure you won't outgrow it - it even stiffly supports the beast below. I think key to the 405 is the robustness of the gearing in comparison to other heads - the 7.5kg limit is too conservative if you ask me. I wouldn't dare try this on an Arca Swiss Cube for example.

Forum: Pentax Medium Format 02-08-2011, 06:27 PM  
FA*300mm F4 on 645d
Posted By VoltMan
Replies: 22
Views: 4,758
Actually I don't find that true in practice - medium tele lenses especially with a rotating collar/mount are just as (if not more) susceptible to vibration issues - probably due to the looser required tolerances in the collar which allows slight movement. On the other hand lenses supported by body mount only require a v. stiff plate and connection to the tripod. The best solution I've found for any tele (Nikon, Mamiya MF, Contax 645) is a 2 point support which puts the fulcrum in the center, e.g. using a "U" frame carrier for the lens (e.g. Mamiya RZ tele) but those aren't widely adopted. Also putting a sandbag on top of the lens to preload the bearings in the collar seems to help - did this many times with a Nikon 600mm with great results.
Forum: Pentax Medium Format 02-07-2011, 08:17 PM  
FA*300mm F4 on 645d
Posted By VoltMan
Replies: 22
Views: 4,758
Royce - I had/solved similar problems with a Mamiya 645AF 300/4.5 - nearly the same foot design (e.g. most rearward) - you may want to consider a single plate like RRS attached to the body and lens with a shim plate under the body to match the level of the foot. In that configuration you do give up body rotation - you'll have to use the ballhead instead of the collar.
Forum: Pentax Medium Format 02-07-2011, 07:51 PM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
List price now advertised (and orderable) in Japan ¥398,000. Depending on shop discount that makes the street price ¥320,000~¥360,000. Yodobashi.com- smc PENTAX-D FA645 25mmF4AL[IF] SDM AW [25mm/F4 645]
Forum: Pentax Medium Format 02-07-2011, 06:41 PM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Perhaps that can be attributed to the high cost of the trendy offices in downtown Itabashi for the celebrity lens designers, plus a lot of margin for rare earth after watching a Sanma special program on TV. I bet they smoke Dektol and drive 1st generation Isuzu Piazzas too. :D
Forum: Pentax Medium Format 02-07-2011, 12:03 PM  
Love My 645 But...
Posted By VoltMan
Replies: 16
Views: 3,374
Sounds like its time to ditch the RZ then and get started in digital!
Forum: Pentax Medium Format 02-07-2011, 11:47 AM  
FA 35mm F3.5 test with 645d
Posted By VoltMan
Replies: 39
Views: 11,374
Steven - I've also dealt with them in the past 8 years or so. My experiences have been positive in that I did get good pricing and they shipped properly (probably now more important for customs given DHS in the U.S.). They're a pretty big "value" dealer in Hong Kong. However I note if you've not dealt with Hong Kong merchants before it could be a bit trying dealing in person as they have a different shopping culture there :D

On another note you may want to clarify that the return policy meets your expectations - in Asia it would not be normal to return a lens because you think its IQ sucks, its more like major problems ("the focus ring is binding") ...
Forum: Pentax Medium Format 02-07-2011, 11:13 AM  
Love My 645 But...
Posted By VoltMan
Replies: 16
Views: 3,374
How many RZ lenses do you have? And how many P645 lenses? For me it would come down to retaining the film system that offered the most flexibility - which the RZ has an upside in that its 6x7 vs. 6x4.5. The downside of course is portability.
Forum: Pentax Medium Format 02-07-2011, 08:44 AM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Yep I understood ostensibly it will cover a FF MF sensor according to Pentax, but given their relative inexperience in MF digital in general as well as in digital lens design its a bit obvious that it will be a long time prior to someone really knowing how it will perform with a FF MF sensor. I think its reasonable to ponder these points at a price point of $5K.
Forum: Pentax Medium Format 02-07-2011, 07:47 AM  
PentaX D-FA645 25mm f/4
Posted By VoltMan
Replies: 61
Views: 14,698
Ouch - that's about ¥400,000 list here. If that rings true in Japan my dealer will have a heart attack when he's at CP+ as he's told several of us now to expect a lower price. I see a deeper discount coming :D



True for MF AF SLR but actually there are several MF manual focus/metering cameras and at least 5 other lenses 24mm and below that can be used with existing full frame MF backs (53x40mm) - the problem is most folks here probably can't afford them or don't need them as they're hobbyists more so than full time landscape or architectural professionals.



The big question I have now though is how will the new 25mm perform on a FF MF sensor? Of course we won't know unless Pentax eventually releases a FF MF digital - which is a pretty big gamble in my mind.
Forum: Pentax Medium Format 02-06-2011, 02:39 PM  
FA 35mm F3.5 test with 645d
Posted By VoltMan
Replies: 39
Views: 11,374
Steven - Yes I do, about 8km south of the main Pentax office and repair center - which I'll be going to this week as some laggard at KEH decided to pack a 67 auto bellows with a single layer of bubblewrap and *both* standards were broken in transit (the nylon bushings). Hopefully they'll have the parts to fix it! --Brett
Forum: Pentax Medium Format 02-06-2011, 06:37 AM  
Pentax 67 300 F/4 EDIF value?
Posted By VoltMan
Replies: 9
Views: 3,561
For what its worth this lens is still sold "new old stock" in Japan at ¥312,000 which is about $3800 USD, and I've not seen one on the used market yet amongst at least over 100 of all the 67/6x7 lenses in either shops or listings here. I started out looking for this lens in particular but wound up getting the M*400/f4 ED(IF) I stumbled on instead.
Forum: Pentax Medium Format 02-05-2011, 05:47 PM  
FA 35mm F3.5 test with 645d
Posted By VoltMan
Replies: 39
Views: 11,374
Hmmm .. that makes the JPY 151,000 - 20% in discount points in Japan for new (old stock) look reasonable given it comes with a warranty :)
Forum: Pentax Medium Format 02-02-2011, 08:16 AM  
645D + 45mm 6X7 with Pentax 645-67 adaptor
Posted By VoltMan
Replies: 32
Views: 10,298
Steven,

BIC Camera and Yodobashi Camera both have large stocks of Pentax FA645 lenses, though only Yodobashi offers all of them online. Amazon lists several in stock but they only replenish their own stock 1 at a time as they get sold. Unfortunately none of them will ship outside Japan nor even have English sites. To get a sense how many are in Japan I can judge that at my local BIC Camera (one of about 10 in Tokyo) they have all of the FA lenses - at a store not really known for medium format photo. At the small shop I go to (also a Pentax dealer) they have a large inventory of both "new" and used stock at v. reasonable prices. Again sorry but they don't cater outside of Japan either. I almost get the sense that its all "normal" here supply wise (however I think the prices are high in comparison to let's say a new design Mamiya Sekor D series). This is why I surmise either the distributors (BIC and Yodobashi in particular) have the majority of inventory under their control, or otherwise have allotments from existing Pentax stock built on liberal agreements to prop up Pentax prior to the 645D introduction.

--Brett
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