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Forum: Pentax Medium Format
01-02-2017, 05:27 PM
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Interesting results and thanks for sharing. I thought about this a great deal (and blogged about it). I reached the same conclusion as I did when first shooting in Iceland with the 645Z and 28-45mm: that lens is so darned useful it covers almost all the wide angle shooting I could want and with stunning quality. The X1D is much smaller and lighter, but if you like the flexibility of working across the whole 21-35mm (in FF terms) range, the big Z lens is a great friend. With my Sony bodies I am regularly changing lenses between the 21-28-35 options and it is a pain in the backside when it is very cold, raining, or I am in a rush, or on difficult ground. With the Z I always seem to be able to get the wide angle shot with that one lens attached. I love it. The fact that the quality at 45mm holds up to the 45mm Hassy prime is quite a testament, but when you consider that the lens is even better in the middle of the range, it says even more.
The X1D is tremendous, but I would personally rather carry the weight of the 28-45 than to carry an X1D with a number of primes and keep changing lenses all the time. If travelling very light and hiking, I have my Sony A7 system and carry multiple bodies to reduce lens changes.
FWIW I have shot two copies of the 45-85 FA, a 80-160 A and FA and all were different! Both my 80-160s were ace, with the FA being a touch better. I find mine very sharp throughout the range, even at 160mm. I just ensure that I stop down well (f13-16) at the long end for best performance across the frame when shooting distant scenes (at closer/medium distances it is tack sharp corner to corner at F9 or so). Diffraction is not an issue at such a focal length in my experience. One 45-85 FA was a mint but badly decentered and very poor after 60mm. The other is ever so mildly decentered (rarely noticeable at all) and actually very sharp up to 75mm or so and very decent at full reach. My 150mm FA is stunningly sharp always, as is my 35mm A, my 200mm FA is very good indeed (one needs care in the wind). I am thrilled that I have such a line up at such a low cost |
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Forum: Pentax News and Rumors
10-05-2015, 09:31 AM
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I'm hoping this is a tweaked Tamron formula, because to really shine on 42MP it could certainly benefit from being a bit stronger than the Tamron, especially in the middle of the zoom range where the Tammy is notoriously weak (and its not that great at the long end). Junking the image stabilisation in the lens may give scope for this... somehow. Exciting times!
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Forum: Photographic Industry and Professionals
10-05-2015, 09:16 AM
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Firstly, I was under the impression that I am perfectly entitled to express a polite opinion on this forum. You however suggest I should 'take it elsewhere'. For my benefit, can you please explain why it is OK for some people to assert that the victim is an idiot (off the back of a truck load of assumptions), but my suggestion that it would be more appropriate to regard this murder victim as, well, a victim, should be taken elsewhere?
Secondly, I have a question in relation to the below: how is it that you are so sure of precisely what occurred and why it occurred? And I do think its the detailed specifics that matter, rather generalised comments about 'usually and normally'. After all, the title of 'idiot' was bestowed upon a very specific victim in one specific case.
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Forum: Pentax News and Rumors
10-03-2015, 08:51 AM
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Forum: Photographic Industry and Professionals
10-03-2015, 08:47 AM
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We do not know exactly what happened and the man lies dead. He *could* have shown defensive wounds that suggest he fought against a robber, but maybe he instinctively fought after being attacked and was unable to deescalate the situation. We do not know, but I think branding a murder victim an idiot is rather bad taste, especially in the absence of solid facts. He went there to take photos and is now dead. People make mistakes.... people are unlucky.... people do not always handle violent criminals the the perfect way. Oh, the benefits of hindsight.
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Forum: Pentax Medium Format
07-08-2015, 04:20 AM
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A service tech should be able to adjust this, but mechanical adjustment is likely to be required.
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Forum: Pentax Medium Format
07-07-2015, 12:31 AM
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Personally, I would not compare the D and the Z. The latter has a much more impressive sensor in my book, live view and a long list of other tweaks that make it a completely different proposition.
FWIW, IMHO the 645z handles much better than big pro SLRs (like the Volvo's 'boxy but good' advertising line!) and shoots much better frames than the A7R. I wrote about it extensively on my blog (the final part being here). Yes, it requires a different approach, but yes you will be rewarded. All of this is fairly unimportant if you are not making large prints, however.
The A7R II looks amazing, but where the Z scores highly is in the quality and selection of the lenses and the fact that cropped to 4:3 the Sony comes out at 38MP, with a higher pixel pitch and much more demand on the lenses. Compared to the A7R, 645Z files are also more robust under heavy processing, showing less noise and better overall quality.
As for the successor, I think its fair to assume Pentax will stick with a 44x33mm sensor as some of the new lenses will not cover full 645. The new lenses resolve so well that they can handle more resolution and upscaled to the same density as the 42mp sensor in the A7R, you get over 70MP....
I think the big issue is how large you print. If its rarely over 30", I'd stick with something smaller.
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Forum: Canon, Nikon, Sony, and Other Camera Brands
07-06-2015, 10:40 PM
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I can understand why you have this impression, because there is lots of half-baked information floating about on the internet. A lot of the early 'lossy compression artifacts' shown on the net were actually found to have been caused by other factors in the end.
I own an A7 and A7R, along with a Ricoh GR and 645Z. My Sony files do not show artifacts when pushed and, as a B&W shooter, I am quite hard on the files. You can look here, where 80% of the images are from the A7 and A7R (along with the Land series). The files are not quite as robust as the 645Z files, sure, but they are more robust than GR files, which sports a sensor shared with other Pentax APS-C bodies.
Sony lossy compressed files can show artifacts in extreme contrast transitions and the only place I have seen these reliably and repeatedly produced is in star trails at night, where there is of course a massively abrupt transition from the etched trail and the black sky. I've shot mine since release and not see problems in my normal usage. I cannot speak for everyone elses experience of course, but I would be surprised if they are different to mine.
In short: I am of the opinion that you can absolutely hammer A7 files in the context of regular photographic output. They may not be the very best out there, but they are close to the top. If your application is in graphical work or extreme non-photo realistic outputs, I cannot comment.
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Forum: Photo Critique
07-06-2015, 10:27 PM
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the bottom one by a large margin.
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Forum: Pentax News and Rumors
07-02-2015, 11:52 AM
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To a large extent this is true and I very rarely covet extremely limited depth of field. I would go as far as to say that I find the fixation upon shallow depth of field as a crutch for otherwise weak photography, however.... where very fast lenses come in handy is in isolating subjects at distance, where depth of field increases for a given aperture. While you may not want to shoot wider than f2 or f2.8 at 70cm using a 85mm lens on FF, shooting the same subject at 2m or 3m may leave you wanting a faster aperture, as at f2.8 depth of field is already growing rapidly. This is why the Canon 50mm f1.2L is so beautiful, because of how it renders subjects at moderate (and not close) distance wide open.
Overall though, I agree. I find it odd that so many Leica 'street photographers' fixate over lens performance wide open when the kinda sorta point of the genre is to kinda sorta see what's going on in the street! This is why the Ricoh GR is so phenomenal, because it has a smaller sensor and amazing performance throughout the aperture range.
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Forum: Pentax News and Rumors
07-02-2015, 08:28 AM
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Yes, exactly: theory vs what is practically available. I'm thrilled with the improvements I have noted with my 645Z over my A7R for pure image quality, for sure.
I hope that Pentax will produce a top notch portrait lens for the 645z and that it is fast! That said, I personally won't be buying one, as I tend not to need the additional quality for my portraits and would use FF anyway. For studio users, I can see why they are eager for something in the sweet spot i.e. 110mm and f2 or faster. That would be really nice on 33x44. 150mm is a bit long for most people I think, but the 150mm f2.8 undoubtedly has a lovely signature to it.
Ironically, I am probably one who regards the 33x44 format as lovely, because I would rather not have to deal with the shallower DOF endemic to much larger sensors (as I shoot scenics and landscapes mostly).
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Forum: Pentax News and Rumors
07-02-2015, 05:58 AM
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I own a 645z and have owned and shot everything from M43 up to 8x10 over the years so I do recognise and enjoy the benefits of larger formats, but think we have to be careful not to ascribe qualities that are beyond the realm of what physics permits (as well as what can actually be seen in real life). I was responding to the notion that MF at f5.6 can achieve shallow DOF that has a quality we cannot see on smaller formats (with the suggestion that anyone having actually shot MF would recognise this). Unfortunately it isn't true and isn't close to being true. 80mm at f5.6 on a true 645 format will deliver vastly more depth of field than f1.4 on FF using a 50mm lens, for example (at a given distance). The 645 and 80mm combo cannot overcome the reduced depth of field possible by the much wider aperture of the 50mm lens, which gives the same angle of view on FF. Sure, shoot the 80mm at f2.8 and the 50mm at f2.8 and the larger format will show less DOF.... but if you seek shallow DOF, clearly you would open the 50mm lens up (whereas many 80mm MF lenses are/were f2.8 wide open).
So, while I agree about the fact that 33x44 has the potential to offer shallower depth of field than FF, in practice this is often not the case due to the speed of lenses available (and in the case of the Pentax, options are somewhat limited). Apart from a few specific examples, there is a greater availability of lenses for FF that will offer shallower DOF across a range of focal lengths, especially in the wider focal lengths. A great example would be 90mm on the 645z. Your only native option is the 90mm f2.8 DFA Macro, whereas with full frame, you are looking at 75mm for the same framing. Here, you may have the option of a Summilux 75mm f1.4 which will offer shallower DOF (as would a 75mm f1.8 CV). If you're not shooting Leica M, you could go a touch longer in real terms and grab the Canon 85mm f1.2L (or Nikkor 85mm f1.4), which will offer far shallower DOF and this is simply because big lenses on FF become even bigger on larger formats as the focal length goes up to maintain the same angle of view, meaning the physical aperture is larger etc. In order to produce less depth of field than the Canon 85mm f1.2, Pentax would have to offer a 105mm lens (for same angle of view) significantly faster than f1.8 (I am not sure of the precise maths). But they don't (thought there is a Hassy 100mm f2 and similar). FF usually wins the extreme DOF race (just as they do when you try to figure out what would be needed from MF to produce less DOF than a FF 600mm f4 lens...), but there are other qualities that are strong selling points for the larger formats.
With 'true' 645, achieving shallower DOF than FF is still difficult. 150mm Pentax f2.8 vs (there is no precise angle of view equivalent) 85mm f1.2 L II or 135mm f2 L. The Pentax still does not win the DOF race. It gets much more interesting when you put a 300mm f4.5 on 10x8!
Tonal transition, colour, resolution, lens quality and bokeh are all different issues and even 33x44 (a smaller leap from FF than FF is from APS-C) does offer very real tangible benefits, but depth of field is unrelated to these.
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Forum: Pentax News and Rumors
07-02-2015, 01:30 AM
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I think this is misleading. There is not magical property to medium format and in the case of the 645z, the sensor is only slightly larger than FF, resulting in the requirement to use slightly longer focal lengths for equivalent framing (compared to FF). Because depth of field is almost entirely determined by focal length and aperture, you get slightly less depth of field for a given aperture when using the slightly longer focal length required by the 645Z for equivalent framing. i.e. a 60mm lens on FF instead of 50mm on FF (0.8x factor).
I think the point the person was making is that there are much faster lenses available for FF and they they more than compensate for the slightly greater focal length required for the same framing on the likes of the 645z. Sure the 150mm f2.8 for the pentax 645 is great for shallow depth of field, but the 55mm f2.8 does not come closer to the 50mm f1.2L for shallowness and there are other, similar examples as far as my memory serves me.
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Forum: Pentax News and Rumors
06-27-2015, 09:41 PM
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The S/N logic only applies if you want to get the largest capture of light by shooting as wide as possible. Its not terribly applicable to landscape shooters, for example. At comparable apertures, in terms of the apparent depth of field, the 645Z is well ahead.
Most of the 645Z's new lenses have shake reduction in the lens (28-45 and 90mm). It would seem likely that forthcoming lenses will have in lens SR too. Sure, for handheld work the smaller FF retains significant advantages, but lens quality remains an issue with the smaller format at wider angles. I hope the Batis lenses will resolve this with the Sony line, but I have yet to use a wide on anything aside from a Leica M that offers the same quality as the 28-45mm DA.
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Forum: Pentax Medium Format
06-25-2015, 11:08 AM
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I bought this amazing camera a few months ago and have already taken it on a long trip to Iceland. I've finally complete my review, along with quite a few full resolution samples slices from whole frames, so you can get a clear idea of how these lenses perform on the 51MP sensor: http://thephotofundamentalist.com/?p=2176 Hopefully it will help those considering such a purchase!
I really struggled to find samples from the 28-45mm DA lens on this camera and so have produced quite a large selection of crops and full resolution slices from edge to edge to give an idea of how well it performs (the answer being astonishingly well).
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Forum: Pentax News and Rumors
06-25-2015, 02:05 AM
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Whatever sensor is in the Pentax FF I expect it to be a very good performer. As for the 42MP BSI sensor, lets remember that the 'package' is sensor plus lenses. I own a Canon system, a Sony FE system and the 645Z with a 28-45 and I have nothing that can compete with the latter. My A7R is kinda sorta close, but has more noise, obviously less resolution with wide angle lenses towards the edges of the frame (by a fair margin) and the files are less malleable. Canon sensors are not in the same galaxy for DR and noise when the files are pushed around. Sure, if you make A2 prints the idea of a 645Z is insane, but even with the new 42MP sensor around, making perfect prints that withstand close inspection at 40" is very lens dependent and there are few FF lenses around that could cope with 36MP, never mind 42. For this, we need a new generation of wide angles.The Batis lenses may get us closer and maybe the Pentax FF offerings will be amazing, but Pentax is already there with many of its new and legacy 645 lenses.
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Forum: Welcomes and Introductions
06-09-2015, 10:16 PM
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Welcome, from another fairly recent 645z owner and newcomer here. Mine surprised me too. I expected it to be good, just not this good.
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Forum: Pentax Medium Format
06-07-2015, 09:32 PM
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Yep, they're bonkers. My 645Z clearly and easily out-resolves my A7R. It also has a significant amount more DR, but how much I cannot say.
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Forum: Pentax K-3 & K-3 II
06-06-2015, 01:51 AM
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Its a great feature, but its not the same thing as high res in single shot mode. I shoot the majority of my work hand-held, or outdoors (and doesn't there always seem to be wind?). I think this is a great feature, that I am sure will also be on the forthcoming FF, not to mention the eventual 645Z replacement, but it is not fair to say it trumps regular 36MP FF from a practical point of view, because it is limiting in use. Its a wonderful additional feature.
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Forum: Pentax News and Rumors
06-06-2015, 01:48 AM
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No. Idea.
We're all used to these sorts of announcements - Canon winning the turkey a year back with their much hyped 'flopcast' - and know it could be revolutionary, or as significant as a new type of plastic being used to manufacture their chassis...
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Forum: Ricoh GR
06-06-2015, 01:42 AM
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There are no heretics, only appreciative users!
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Forum: Pentax Medium Format
06-06-2015, 01:26 AM
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You are right about bragging rights, but I'd without question be staying with Canon were they to have introduced a superb new-tech 36MP sensor, like the one in the D810. As it stands, the one in the 5DS is still a 12 stopper and I have yet to be convinced that pattern noise will be under control to anywhere near the extent of the Sony sensors. The flexibility these things give me in PP is far more valuable than the extra pixels from 36 to 50MP, at least as one considers the limited ability for FF lenses below 35mm to handle this resolution off centre.
I shoot B&W and come from a darkroom background and its amazing how hard one sometimes has to torture file to make it look like a top-quality hand print! So.... in short, the 5DS does not impress at all. Its like stuffing an oversized engine into an old model car and saying, "look, here is the latest and greatest". It doesn't remotely convince. You can brag horsepower all you like, but I'm not interested if it won't go around corners!
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Forum: Ricoh GR
06-05-2015, 09:37 AM
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Seems unlikely that the camera would stay put. I agree its amazing as it is, but there is always room for progress and I cannot see Ricoh changing nothing under the hood so to speak.
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Forum: Pentax Medium Format
06-05-2015, 05:19 AM
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Totally agree re barrel distortion of the 28-45 lens, but I shoot natural scenes and have no images that do not correct perfectly, when needed.. For urbanscapes, it may prove challenging and with the 25mm's curvature that could work in your favour if inside the city, rather than looking at it from afar, if you follow me.
I think Pentax is four lenses away from being in a commanding position (for scenic shooters):
Using real, rather than converted focal lengths:
20-22mm prime.
28mm filt/shift
45-85 replacement
80-160 replacement.
Anything they add after this will be a bonus. I'd like to see:
18mm prime
45mm tilt/shift
and then I'd be struggling. Perhaps a slow but razor sharp 150-300mm zoom would be worthwhile, but ...
There is no doubt the 28-45 DA and 75mm FA will handle more resolution, along with the 90mm Macro, so I think we can expect to see a mild refresh of the 645Z in a few years with circa 65-80MP. The body is close to perfect, if you ask me.
For portrait shooters I can see the urgent need for some really characterful and fast lenses between 60 and 120mm
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Forum: Pentax Medium Format
05-31-2015, 11:33 PM
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I can only comment on SD cards, but I have used a bunch of different Sandisc, Integral and Transcend and no issues, but make sure you format the cards first. I had an issue with one card that I forgot to format while in a blind rush and it threw me an error after 100 files or so. All files were fine though, so after a format, I went on my merry way.
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