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Forum: Pentax Medium Format 05-17-2019, 10:37 AM  
Is The Worlds Greatest Camera the 645D and Its CCD Sensor?
Posted By donesteban
Replies: 17
Views: 3,752
I am landscape photographer and I own both the Z and the D.

The D works perfectly with almost any of the 645 and 67 lenses when stopped down. There are a few exceptions staying soft on the 645D even if stopped down, for example the 645 55-110 on the long end. But most of the lenses are just great for landscape photography on that camera.

The Z is much more picky. Off course, the new lenses like the 55 AW, 28-45 and 90mm macro are grat on the 645Z, too. But some of the old lenses aren't. For example the 67 55-100 and 90-180 zoom.

Yes, the Z has more dynamic range. In most of the cases the dynamic range of the D is sufficient, tough. There is one exception: If the sun is on the picture and it has thin clouds covering the sun partially or just next to the sun. In that case, not only the sun is white, the clouds are, too. With the 645Z no problem at all. I remember I had to use both the 0.9 and the 0.6 GND filters to fix this problem on the 645D, that's 5 stops. For the same pictures I don't need any GND on the 645Z. I guess this is infrared light which is not filtered that well by the clouds, and the 645D is most likely more sensitive to infrared light. It is not the total dynamic far too high for the 12.5 stops the 645D offers, a slight 1 to 2 stop GND would do the job, there is happening something else.
Forum: Pentax Medium Format 02-16-2019, 10:04 AM  
200mm f/4 645 with 1.4x teleconverter?
Posted By donesteban
Replies: 7
Views: 1,251
I was never that happy with the 200/4 and the 1.4x TC. It was OK, if contrast was quite high (landscape in direct sun light), but too soft of landscape with lower contrast.

The 150-300 has come down to 400 $ in Japan, and that zooms shows better quality with the 1.4x TC at the long end, With one restriction: 645D. It works not that well on the 645Z. The 645D does not yet have gapless micro lenses and thus has higher micro contrast. Without the 1.4x TC, the 150-300 does a perfect job on the 645Z, too.

I have comapred it to teh FA 300/4. The FA is one stop faster (obviously) and the bokeh is a bit somther than the zoom. Beside that: Hard to find adifference on the pictures.
Forum: Pentax Medium Format 02-14-2019, 08:23 AM  
Capture One?
Posted By donesteban
Replies: 10
Views: 2,641
I use EXIF tool to do this job. I have created a Desktop icon, calling exif tool with the right parameters. So after copying the files on to the computer, I just have to select them all and drag and drop them onto the icon. And just wait for EXIF tool to change the files. It is quite I/O intensive, as it will write the full file again. So an SSD or a RAID 0 of two 3.5" HDD might be a good idea here, if you want to convert a lot of files.
By the way: The 645D works directly in C1 10 pro, you just have to make sure you use the right RAW format on the camera. The workaround is for the 645Z only.
Forum: Pentax Medium Format 11-20-2018, 07:21 AM  
100mp 44x33mm Medium Format Sensor
Posted By donesteban
Replies: 54
Views: 7,320
Well, whtat I wanted to say is this: They have not been able to provide a 21 to 23mm for the small sensor yet. If they would switch to the big sensor, they would have to provide a lens of about 28mm for this big sensor, as the 28-45 will not work on full 645 (I tried it myself on a film body, it is even not working unofficially). So they would have to build two new wide lenses when switching to the new sensor (about 22mm for 44x33 and about 28mm for the bigger sensor), or maybe merge the two it to one 24 or 24mm lens covering both systems (a bit wide for the big sensor and a bit longish for the small sensor, but still somehow OK).

The digital system is suffering form bad decisions in the past years. The 90mm macro is a very good lens, but for macro usage, the old 120/4 is as good and provides 1:1, not just 1:2. Why did they spend this high effort in bringing another "macro" lens? If I just imagine they would have developed a 120/2.0 LS instead for portrait and studio work with flash sync up to 1/500 or better...
And then the 28-45. Yes, a great lens, too, and matching very well to the rest of the system like the 45-85 or the 55/2.8. But a bad choice, if you are not able to provide the real super wide, too. If they knew from the beginning, they can only build one lens shorter than the 35mm, something between 21 and 24mm would have been the way to go.

Well, Fuji is now building these lenses. The 23mm is available there, a 110/2.0 as well. I think their managers are photographers, too.

In this situation, I don't think they will bring a 100 MP solution. Either big sensor with pixels only a little bit smaller, or some sensor seize, but much smaller pixels, both of them will need new lenses. The large sensor on the super wide side, the small 100 MP sensor will need high resolution replacments for some existing lenses, for example the 80-160 or the 150/2.8
Forum: Pentax Medium Format 11-19-2018, 05:14 AM  
100mp 44x33mm Medium Format Sensor
Posted By donesteban
Replies: 54
Views: 7,320
At the time Pentax was reported to have signed a contract with Sony to be allowed to use the 100 MP sensor, there was the large one only.
I think, this sensor would still be available to Pentax, although it will be quite expensive.

The problem is most likely, Pentax is not willing to spend that much money, as it requires to develop a new body with the new sensor. They have even not been willing to develop a super wide angle lens for many yeras now. The 645 digital system is optimized for landscape photography. While this doesn't mean you have to offer a lens with 10 oder 12mm equivalent on a full frame DSLR, as this is really special, even in landscape photography, it means fpr sure you have to offer something in the 16 to 18mm FF equivalent. The old 25mm was about 19mm FF equivalent, so at least somehow close to this range. The 28-45 isn't, imagine Nikon or Canon not offering any lens wider than 22mm for their FF DSLR systems.Off course, Pentax didn't notice immediately there was a problem after discontinuing the 25mm. The 645Z was selling quite well. But this was mainly upgrade from the 645D, as the new sensor really has some big advantages. In my opinion, the number of customers, buying a 645Z body without owning a 645D body before, was getting quite small without the possibility to buy a 25mm, too.

And now, some years later, there is still no DA 21mm oder 23mm filling that gap. This company is not willing to develop such an important lens. With the bigger sensor, the 28-45 would not be compatibly anymore. So going in direction of bigger sensor is just nonsense, if Pentax is not able to develop a new super wide lens at the same time, too. Even worse, they would need a 21mm for the old 33x44mm system and something between 25 and 28mm for the full size 645 system. Well,a 24mm fitting both might be a compromise, OK.
Forum: Pentax Medium Format 10-22-2018, 04:02 AM  
100mp 44x33mm Medium Format Sensor
Posted By donesteban
Replies: 54
Views: 7,320
There are two 100 MP sensors. One is 33x44mm, one is 41x54mm.

If talking about the small one, like Fuji is using it in the GFX 100 MP, well, that's right, pixels are 1.4 times smaller than at 50 MP. So pcitures might get softer If we llok at them at 100% and diffraction will start one stop faster, so stopping down further to solve the problem is no option. On the other hand, lenses that work well using the 1.4x TC on 50 MP, will do a good job on the 100 MP without TC for sure. Even the best 1.4x TC will just enlarge all softness by 1.4x, and real world TCs will add some further softness, too.

Then, there is this larger, sensor, too. Only the 28-45mm will not work on that one, as it is a real "crop" lens. So if going thes direction a new super wide lens will be rquired, too. But: The pixel pitch of the 645Z is about 80 MP in that sensor size. So pixels will not become much smaller to reach the 100 MP. I don't think the inner 33x44mm of thet sensor will show a noticalbel difference in sharpness at 100%, if we go to 100 MP using the big sensor. Maybe minor difference, but not much. Pixels will only get 1.13x smaller, not 1.4x. The trade off *might* be outside this 33x44mm area on the borders. The bigger sensor is as wide as the diagonal of the smaller one. So the borders at the middle of the picture hight of the bigger sensor will have the picture quality of the corners of the smaller sensor. Hard to predict what this means to the corners of the larger sensor. Wll, I'd guess, the good 67 lenses would have any problem with that, as it is still a crop sensor from their point of view. But it might be different for some 645 lneses in the way, that some can have blur in the corners, even when stopped down.
Forum: Pentax Medium Format 10-22-2018, 03:38 AM  
Letís talk 645z image editing software
Posted By donesteban
Replies: 27
Views: 2,873
Well, if you are woning a Mac, Hasselblad Phocus would be an option, too. Off course, without the advanced features like layers,.. the work for Hasselblad cameras only. But the basiv features are supported for every Camera supported by OS X. The 645Z is on that list. Hasselblad Phocus can be downloaded for free.

I have been using Phocus quite a long time, Then, one day, I found out, Capture One 10 Pro supports the 645D (the D, not the Z). Up to a few days before, I was only owning the D. I knew Capture One 6, from former times, when I was using the D2x, and I loved the software. So I just purchased the 10 pro version.

As I am quite used tu capture One, I deceided to go the way of changing the EXIF data. I have an Icon on my desktop, with a short cut to exif tool with some predefined options. All I have to do is drag and drop the pictures on thet Icon, and Exiftool will convert all of them for me. Off, course, this may take a while, mainly depending on I/O speed of your system. Exif tool will write the whole file again, so it can be many GB of data, if there are plenty of photos to convert.

I don't like Lightroom at all, as you have to use the catalog. I use my own mechanism to manage files, based on folder names.

I I'd have to compare these two softwares to each other and to other programs, C1 does a better job on reducing noise and keeps a little bit more detail in the pictures. But also Phocus will significantly more details in the images than Lightroom, for example. Lightroom is better than both of them at very high ISO. C1 will create very "punchy" pcitures with high saturation out of the box, Phocus creates very neutral pictures with quite low saturation by default.
Forum: Pentax Medium Format 01-12-2018, 04:18 AM  
"downgrade" from 28-45 to 33-55?
Posted By donesteban
Replies: 11
Views: 1,982
The 45 A has arrived. It is very sharp wide open in die middle of the Frame, and fair on the borders. The Problem is: It is not getting much better on the boders by stopping down. Even f/11 is a big difference on the borders to the 28-45, while in the middle it is hard to find a difference at any apperture.
I'll Keep them both. Because the 45/2.8 seems to be grat for Portrait work. The 28-45 is slower and has really bad bokeh. The 45/2.8 has quite a good bokeh!
Forum: Pentax Medium Format 01-04-2018, 03:13 AM  
"downgrade" from 28-45 to 33-55?
Posted By donesteban
Replies: 11
Views: 1,982
I ordered a SMC-A 45/2.8 in Japan. Before checking the 33-55, I'd like to see if the 45mm is a good landscape lens, too, if stopped down. Besides that, I'd like to have a look at the bokeh, too. It might be suitable for some portrait work, too, if the bokeh is good. Maximum sharpness is not needed for that, so I woulnd't matter if it is not that sharp wide open.


If the 45/2.8 is doing the job, I'll use the 35 A and the 45A instead of the 28-45.
Forum: Pentax Medium Format 01-02-2018, 04:18 AM  
"downgrade" from 28-45 to 33-55?
Posted By donesteban
Replies: 11
Views: 1,982
Well, I bought the 28-45 because I was curious. It was 2nd hand, too, so my financial loss compared to what I paied will be small if selling it again.
I already own the 645 55-110. The build quality of the 33-55 should be the same, shoudn't it?

Yes, the inner tube of the 55-110 is quite unfirm comapred to my other Pentax MF gear. But it is not affecting picture quality.

I don't consider the build quality of the 28-45 that good, either, from my point of view it is just like a huge and heavy brother of the DA 18-135 WR.
Nothing I would think of comparing to my 67 55-100 and 90-180 in terms of build quality. Or to the Sigma 24-35/2.0 in my Nikon System.


The 28-45 has only three big strengths in my point of view. sharp, sharp and the SR.


Looks like there is no other way than just odering one 2nd hand from Japan. I could accept if the lens is a bit less sharp and has to be stopped down to get sharp.
Also, 33 to 45mm would be the most important part rearding picture quality, as 55mm is already covered by the 55-100 67 in a great manner.
The only thing I am not sure about is still the 35 plus 45mm vs. the 33-55mm question.
I already own a 35 SMC-A. It is great. Is the 45mm FA really softer than the 33-55 at 45mm?
Forum: Pentax Medium Format 01-01-2018, 02:01 AM  
"downgrade" from 28-45 to 33-55?
Posted By donesteban
Replies: 11
Views: 1,982
Too much gear. I am trying to avoid this where ever possible.
Off course, temporarly it would be possible to be able to comapre them. But after a few weeks, one would have to go.

I have a Nikon system and and Pentax APSc system beside the 645D. It is really getting too much if I keep everything I'd like to have.
Forum: Pentax Medium Format 12-22-2017, 06:27 AM  
"downgrade" from 28-45 to 33-55?
Posted By donesteban
Replies: 11
Views: 1,982
Well, landscape. The bokeh of the 28-45 is quite bad, whenever I Need some bokeh in wide angle, I use the Sigma 24-35/2.0 on a D810.


For 35mm, I already own the A Version. I love that lens, too. But I'd be missing something at 45mm.


I use two bags, each of them Holding a whole set of lenses. The "big" one is currently 28-45, 55-100(67), 120 A, 150-300 and 1.4x TC. The "small one" the 35A, 55-110 FA and 90-180 (67), plus a 1.4x TC, too.


I think I could replace the 28-45 either by a 33-55, if that one works well enough. Or by 35 und 45mm Don't know how well the 45mm works, though.
Forum: Pentax Medium Format 12-22-2017, 12:55 AM  
"downgrade" from 28-45 to 33-55?
Posted By donesteban
Replies: 11
Views: 1,982
Hi all,


I am thinking of replacing my big and heavy 28-45 by the samller 33-55. I do at least 90% of the photos taken using the 28-45 not at the short end.
I know I'd loose the SR. It's a nice feature, but not that effective as I am used it from other cameras.


But what's about image quality on the 645D? I can accept to stop down to f/8 or more to get sharp borders. Will the 33-55 be very good on the borders, too, when stopped down to f/8? It doesn't have to match the 28-45, I'd say if it gets as good as the 45-85 gets stopped down, I'd be really happy with it.
Forum: Pentax Medium Format 03-06-2016, 12:20 AM  
Pentax-A* 645 300mm F4 ED [IF]
Posted By donesteban
Replies: 3
Views: 961
Think this is realistic , if it is not mint, for example some scratches in the painting, but optically very good (no scratches on the lenses, no haze, no fungus, just some dust inside), 500$ should be sufficient. If you are looking for on that is mint condition, it is likely to be up to 800.
You can get even cheaper ones if looking for those that have small problems. For example, a scratch in the front lens does not really matter on a telephoto lens, but the price will be much lower.
Forum: Pentax Medium Format 03-03-2016, 12:11 AM  
Long Lenses on 645z
Posted By donesteban
Replies: 22
Views: 2,800
Could this be related to the connection between camera and the quick release plate (or the tripod head directly, if not using quick release plates)?

I remember simlar problems from the times I was using the 67 II and a Hasselblad scanner. I had several Gitzo and Manfrotto ball heads, non of them really fixing the issue. The plates are to small.
I started to get besser results by using one of these old Gitzo off center ball heads, without quick releease plate. They have a quite huge area to fix the camera on. I think it was series 2. Unfortunately, moving the head was not as smooth as with modern ball heads, and I wanted to get quick release, too.

I now use Sirui TY-70X plates, that's arca style, about 3 by 2 inches. Compared to those old, small quick release paltes Gitzo was offering this is much better. And when attaching the plate to the camera, you do it typically much tigther than when mounting the camera on a tripod head not having a quick release plate.

My test to find out the plate was the problem was quite easy. I knew how mouch force it needs to hold the camera on the body only with the largest lens attached (off course, don't do that with a huge lens inteded for tripod only, like a 600mm, but a lens of 3 to 4 pounds and at least 8 inches long is a good example here to tell how much froce to use)
I just put the camera on the tripod and then was using this amount of force trying to totter the camera on the tripod. I was shocked how much the camera was tottering, and it was even easily visible it was amlost all between camera and quick release plate.
Forum: Pentax Medium Format 02-16-2016, 05:01 AM  
Tripod head for 645Z
Posted By donesteban
Replies: 57
Views: 5,937
Well, for my 645d, I use the Marsace Fb-2. Sufficient for the 300/4 *. I sometimes use it with the 1.4x converter, too.the smaller Fb-1r was a bit too small for the 300 mm lens.
The head was about 170$ in Taiwan.
Forum: Pentax Medium Format 02-16-2016, 12:58 AM  
75mm LS Lens
Posted By donesteban
Replies: 4
Views: 850
Well, if you are in Tokyo by occasion, you might have a loOK at the well known dealers having a big 2nd hand department, like map camera or fujiya .
Got my 150-300 at map camera, they had 5 or 6 I could choose from. All 2nd hand.
Forum: Pentax Medium Format 02-09-2016, 07:45 AM  
New 28-45 lens or 645Z?
Posted By donesteban
Replies: 31
Views: 4,244
Well, beside nice to have things like the tilting screen, what does the 645z offer as real big advantage? Live view is nice to have from my point of view, too as the focus indicator in my 645D has always been very precise.
Well, the dynamic range of the 645D is not bad and sufficient for many things, but for example when shooting into a sun rise or sun set, even if the sun is not on the frame, it sometimes is a bit tight and filters should be used. The 645z offers two stops more of dynamic range at low ISO, so it is replacing a 2 stop graduate filter. That's not doing the job alwa, but sometimes it is. And sometimes it is hard to use such a filter, because of an abnormal shape in the picture.
On top of that, the 645z offers much more high ISO. Which isn't that big advantage for a landscape photographer running his I camera at Base ISO on a tripod. But for portrait work, in case you hate using flashes, it is a huge advantage.

Now regarding the lens: The 28-45 offers finder details (often called more sharpness) and wider field of view. Now if the 35mm is alway wide enough for you, the wider filed of view is nice to have. But in case you are suffering right now because 35mm is not wide enough, there is nothing more to discuss, get the 28-45mm.

Now let's put those 28 vs. 35mm away for a moment. What would be an advantage of that lens? Well, it is most likely the sharpest lens you can get in this range. This is easily compensating for the 40 vs. 50 MP, as that is only roughly 10% more pixels in each direction. I bet the 28-45 on a 645D shows at least the same amount of details at the borders of the frame als the 35A oder 35 FA on the 645Z. Most likely 28-45 on the D is even slightly better at the borders.

Conclusion:

If suffering because 35mm is not wide enough, there is no question.
If the 28mm instead of 35mm is nice, but not crucial:
a) You like using a tripod for landscape photos and for your portrait work a flash if light becomes short: Get the 28-45, getting the sharpest lens you can get is more important than 25% more pixels
b) You like doing portrait work at low light without using the flash and you hate carrying around a tripod: Get the 645Z instead.
Forum: Pentax Medium Format 02-01-2016, 10:50 PM  
A35 vs FA35 vs 33-55
Posted By donesteban
Replies: 32
Views: 5,653
Would be interesting to know if the 33-55 at least at f/8 or f/11 is as sharp on the 645D or 645Z as a really good zoom, for example the 45-85 . I am pretty sure it is not able to match the 28-45 at any aperture. But the same sharpness as the 45-85 would be sufficient for many things and sharpness wide open is not a killer criterion for landscape photography. Just as an example, the 55-110 is not able to offer the sharpness of the 45-85 at the border. Nevendon at f/11.
It is quite hard to find full size landscape sample pictures of the 33-55 taken using a 645D or something 645z.
Forum: Pentax News and Rumors 01-25-2016, 08:12 AM  
Final Countdown to Feb 25th 2016 (CP+ 2016)
Posted By donesteban
Replies: 1,654
Views: 188,854
I see also some difference at the banknote, which is quite close to the middle. And off course the 50/2.8 is likely to be better at the corners. But this is just even more stressing high quality lenses are needed, isn't it? Currently, the FA 31mm is the widest prime supporting full frame officialy. And that one is a great lens, but not mainly for shaprnes at the borders, it has other great strengths than that. Didn't they say they are going to dicontinue one or some of the FA limited? Would turn it even worse, if discontinue des not mean replaced immediatley by a successor.
Which lens wider than the 50/2.8 would one chose if chasing for details up to the borders? The 645 35mm line? I know the 35 A 645, it is a great piece of glass and certainly suitable. But wider than 35mm?
36 MP and the multishot sensorshift feature are great, but they will require great lenses, too.
Forum: Pentax News and Rumors 01-25-2016, 07:48 AM  
Final Countdown to Feb 25th 2016 (CP+ 2016)
Posted By donesteban
Replies: 1,654
Views: 188,854
Did I miss something about K3II and 645Z?

I knew only that one:

Studio shot comparison: Digital Photography Review

Please have a look to the 20 SHILLING banknote and check for details. That's still quite close to the middle to the frame. More interesting at the corners (take any you like) and check those USAF resulotion measuring patterns.

But maybe that's just sample variation? I see the D810 slightly ahead on the banknote and quity far ahead at the corners.

That's why lenses will be the point deciding the resolution, sensor shift is less important than the lens and can only help furhter, if the lens is superb.

That said, Pentax has the knowledge to develop very high quality lenses, just have a look at 645 lenses presented in the past 2 years. They just have to do it. It doesn't have to be that much choice, 24/2.0 and a 35/1.4 for example will do it instead of 20/1.8, 24/1.4, 24/1.8,..... like others offer, but a minimum chioce of high quality lenses has to be given if takling about high reolution. And they have to be avialble soon, 2 years after the body is too late.
Forum: Pentax News and Rumors 01-24-2016, 02:46 PM  
Final Countdown to Feb 25th 2016 (CP+ 2016)
Posted By donesteban
Replies: 1,654
Views: 188,854
So what options will Pentax have, ofering les than 24mm and coverage of the full sensor? I understand they cannot offer the same choice as Nikon or Canon, but at least one real wide lens (non fisheye) has to be available. So they'd better get the lenes up and running. A 2500$ pro DSLR body is not the same like a small, light mirrorless for 500 or 800$, where people more easily accept that a 18-55, 50-200 and 2 pancakes is all they can buy to fit this camera. Sigma, Tokina and Tamron are not urging for that Pentax FF market either, so won't be easy to fill all the gaps by their lenses, right?
And they should have a look at primes, too. Well,the 24-70/2.8 is certainly a good zoom lens, offering about the same quality as the Nikon and Canon. Great, but both Canon and Nikon have prime lenses too, at 20 24, 28, 35mm, going beyong the zoom lenses in terms of resolution,... So the 36 MP aren't at the end the same as the 36 MP in a D810 or the 50 MP in a 5Ds R, bet the 5Ds R in combination with the 24mm L will be clearly better than the 24-70/2.8 Oentax/Tamron on a 36 MP, be it a Pentax or Nikon body?
Forum: Pentax Medium Format 01-24-2016, 12:56 PM  
75mm LS for 645
Posted By donesteban
Replies: 28
Views: 2,405
Well, I was looking for a second 75mm some weeks ago. I already had the 75 FA. A second one would have cost about 400$ inlcuding shipping and taxes, when oderign in Japan. 2nd hand off course.
So I was first looking for an ordinary 75 A. But than I saw the 75mm LS, here in Europe, for about 250$, brand new. Well, that was an easy decision. Was a shop in Germany. Sometimes yu really find such things on Ebay.
Forum: Pentax Medium Format 01-16-2016, 11:38 PM  
Is 200 the Native ISO for the 645D?
Posted By donesteban
Replies: 17
Views: 2,593
Turn off highlight recovery function? If that one is on, ISO 200 is the lowest you get.
Forum: Pentax Medium Format 01-05-2016, 01:07 PM  
A35 vs FA35 vs 33-55
Posted By donesteban
Replies: 32
Views: 5,653
The 2845 is not doing full 645.

I use the 35 A as wide anlge, plus a 645N body in case the 645D and 35mm is not wide enough. Typically, I then do the same image again with the 645D as a one row panorama, if possible. But I first use the film body to compose the image. And in case the light is already gone or what ever, I have at least the slide film.
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