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10-02-2011, 08:30 AM   #31
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QuoteOriginally posted by Digitalis Quote
just a word of warning, Medium format backs without AA filters can suffer from colour shifts with tilt/shift lenses. It is a common enough issue that in Capture one 5 they have a correction filter for eliminating the green/magenta colour cast.

from what I understand, this phenomenon is caused by an interaction between the Microlenses and the sharp angle of light striking them.
Lens cast is not a product of the AA filter, but vignetting. Micro lenses compound the problem, but that can be corrected depending on the tilt.

10-02-2011, 08:36 AM   #32
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QuoteOriginally posted by Digitalis Quote
however, that is largely dependant on how large you are printing. DOF issues are magnified substantially by how large the image is printed, and with 40Mp you can produce some pretty large prints indeed; Can you say that everything from the moss on the rocks to the trees on the hills will be rendered crisply at 8x10,16X20,32X40 or 64X80?

I know large format photographers who are using full chip 645 digital backs that are focus stacking to increase DOF.
Not really. You can print as large as you want. The DoF will be fine as print viewing distance increases with print size. DoF changes with relative viewing distance, not print size. I have just put up a 3,5 x 12 foot pano shot with the 645D and there is no problem. I have made plenty of 30 inch and 40 inch prints.

Focus stacking is away around limits of DoF, but introduces its own problems. But it does let you use larger aperture with less diffraction. But I think you will find the effect of diffraction overstated.
10-03-2011, 09:15 AM   #33
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QuoteOriginally posted by Pl Jensen Quote
But DOF is rarely a problem for the 645 format; particularly not the cropped 645D format. How close foreground do you need?
Examples of very close foreground with the 645NII:


Magnificent pictures !

QuoteOriginally posted by riclib Quote
I have the Hartblei 45, adapted in ukraine to the Pentax mount. The lens is lovely engineered, you can find it on ebay.

The field of view looks like 35mm, give or take a couple.

In initial testing shifting beyond 8mm limits sharpness in the corners with my copy, maybe I need to also tilt a bit.

Focusing with the standard focus screen is really difficult though, be ready to focus by trial and error.
Please, would you be so kind to show us sample photos taken with your equipment, even Hartblei have not tried, which is a pity for the commercial success of their new TS 45m f/3.5 Super Rotator as improved for digital sensors.
10-04-2011, 08:27 AM   #34
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btw. Does anyone know if there's a shift adapter for the 67 system?

10-17-2011, 05:07 AM   #35
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My Hatblei 45MM for Pentax 645 (the new version) arrived Friday from Vitaliy at Tilt Shift. . First images show softness on the edges wide open, which is to be expected. I grabbed a few shots at F8 and the image seemed consistently sharp across the frame. The mount feels a bit tight, the rotating ring could be a bit looser for stitching purposes. Focus ring and aperture are nice and smooth. Fit and finish is not equal to Carl Zeiss, but neither is the price. I will do a full test this week and post some images.
10-17-2011, 07:22 AM   #36
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Thanks Aboudd, I wait for these with impatience.
10-17-2011, 08:03 AM   #37
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QuoteOriginally posted by Aboudd Quote
My Hatblei 45MM for Pentax 645 (the new version) arrived Friday from Vitaliy at Tilt Shift. . First images show softness on the edges wide open, which is to be expected. I grabbed a few shots at F8 and the image seemed consistently sharp across the frame. The mount feels a bit tight, the rotating ring could be a bit looser for stitching purposes. Focus ring and aperture are nice and smooth. Fit and finish is not equal to Carl Zeiss, but neither is the price. I will do a full test this week and post some images.
I will wait
10-22-2011, 03:49 AM   #38
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medium format basics

QuoteOriginally posted by erick Quote
I cannot imagine shooting Architecture Landscape without a tilt shift lens, wide of course
... let me add to that ...
I cannot imagine why you would use a Pentax 645 for shooting architecture or landscape in the first place. If tilt/shift is required go for a technical camera, like Alpa or Cambo. Tilt is rather problematic with wide angle lenses as image circle and lens to sensor distance really do not allow for much tilt. All-in-one medium format cameras are useful for portraits and tele work. Shift, tilt, technical stuff is the domain of technical cameras. If you want to live in both worlds get a medium formart camera back that can be mounted to several cameras. Otherwise stay in Cannon land. Do you realize how oversized the Canon TS lenses are compared to the image format? A medium format equivalent would be huge and still offer less movements than a techncal camera.

10-22-2011, 03:58 AM   #39
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QuoteOriginally posted by Digitalis Quote
just a word of warning, Medium format backs without AA filters can suffer from colour shifts with tilt/shift lenses. It is a common enough issue that in Capture one 5 they have a correction filter for eliminating the green/magenta colour cast.

from what I understand, this phenomenon is caused by an interaction between the Microlenses and the sharp angle of light striking them.
Get the correct sensor in the first place. Less trouble with Dalsa sensors - all Leaf and new Phaseone backs.
10-22-2011, 03:47 PM   #40
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QuoteOriginally posted by zapp Quote
Get the correct sensor in the first place. Less trouble with Dalsa sensors - all Leaf and new Phaseone backs
with the Pentax 645D, we don't have a choice. I wouldn't say Dalsa sensors are immune to the lens shading issue, but they do handle it better than Kodak sensors do.

and I have no interest in phasemia cameras - they aren't weather resistant, and a problem I have frequently heard from users of phasemia gear is that sometimes the sensor is way off the 0.5mm +/- alignment tolerance for the camera body, and phasemia camera bodies do not have AF adjust, so there is no effective way to compensate if the sensor is incorrectly positioned apart from replacing the entire camera or returning the digital back. With the 645D body being produced with the sensor built in it means the 645D is more likely to be within the specified tolerances.

Last edited by Digitalis; 10-22-2011 at 03:53 PM.
10-23-2011, 03:26 AM   #41
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Hi Zapp - One would use a shift/tilt lens on a 645 for the same reason as on a Nikon or Canon with PC or TS-E lenses, which I have been using for many years. The SHIFT! More or less sky or foreground, the ability to stitch seamlessly, changing the depth of field with the tilt yet with a larger sharper sensor. As to the issues on MF 645, like CA, if it is correctable in CS5, it is no big deal. Unfortunately, except for Hasselblad's very expensive system and the slow working tech cameras choices are limited. Considering that Pentax makes only two 645D oriented lenses at all, one impossible to find, it is no surprise there is no Pentax brand shift lens.The alternatives aren't great either. There is the cumbersome Zoerk system which uses 67 lens with an adapter and the Hartblei glass. The limitation on both is that at 45MM or so the glass isn't wide enough, certainly not for shooting interiors. A 35MM TS would be great, but alas, none exists.

So far the results with the Hartblei lens is less than thrilling, no where near the performance of the Nikon PC lenses, so I guess there is something to the limitations of shift on MF. However, Leica did announce with the introduction of the S2 that they were planning a shift lens. If I live long enough to see it I would expect them to solve the issues and create an outstanding lens.
10-23-2011, 02:35 PM   #42
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QuoteOriginally posted by Aboudd Quote
So far the results with the Hartblei lens is less than thrilling, no where near the performance of the Nikon PC lenses, so I guess there is something to the limitations of shift on MF. However, Leica did announce with the introduction of the S2 that they were planning a shift lens. If I live long enough to see it I would expect them to solve the issues and create an outstanding lens.
I hope you will also be excited about the outstanding Leica price tag...if Leica does make one it will most likely be the most expensive T/S lens in history.

Last edited by Digitalis; 10-24-2011 at 12:16 AM.
10-23-2011, 03:45 PM   #43
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QuoteOriginally posted by Aboudd Quote
Hi Zapp - One would use a shift/tilt lens on a 645 for the same reason as on a Nikon or Canon with PC or TS-E lenses, which I have been using for many years. The SHIFT! More or less sky or foreground, the ability to stitch seamlessly, changing the depth of field with the tilt yet with a larger sharper sensor. As to the issues on MF 645, like CA, if it is correctable in CS5, it is no big deal. Unfortunately, except for Hasselblad's very expensive system and the slow working tech cameras choices are limited. Considering that Pentax makes only two 645D oriented lenses at all, one impossible to find, it is no surprise there is no Pentax brand shift lens.The alternatives aren't great either. There is the cumbersome Zoerk system which uses 67 lens with an adapter and the Hartblei glass. The limitation on both is that at 45MM or so the glass isn't wide enough, certainly not for shooting interiors. A 35MM TS would be great, but alas, none exists.

So far the results with the Hartblei lens is less than thrilling, no where near the performance of the Nikon PC lenses, so I guess there is something to the limitations of shift on MF. However, Leica did announce with the introduction of the S2 that they were planning a shift lens. If I live long enough to see it I would expect them to solve the issues and create an outstanding lens.
Pentax never mad a TS lens for the 645 series.

The Hartblei is good, stopped down but not Pentax SMC quality.
It is a simple, fast solution without taking out the 6X9, Super Angulons and Super Symmars which is the perfect solution given that time on your side.
10-23-2011, 11:18 PM   #44
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My Leaf back was off by 0.3 mm which is horrible and absolutely visible in imagery. The Alpa Shim Kit corrected for it easily! You do not only need the digital back, but also the right camera (system).
Shift lenses on SLR cameras for wide angle shots are pushing the limits. Admittedly the limits can be pushed quite far these days, but some people do not get what difference a mirror in the path of light means for wide angle lens construction plus shift plus tilt. I can shift a 200g (35mm) tech lens farther than a 2 kg Leica lens with better image results and no visible distortion to correct. Btw the Leica lens is not yet available.

Wide angle Super Angulons are not what you want to use on a digital sensor.

Zoerk and Hasselblad options are interesting tools, but not the professional solution. Check out what the pros use and figure out what you can get for less money. Canon/Nikon T&S lenses are probably the best choice for most people.

If the Hartblei lens does not match a 35mm format lens' performance, stick to 35 mm cameras until you can afford a real tech camera.
10-24-2011, 06:31 AM   #45
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It is a given that anything Leica produces is going to be ridiculously expensive. It is also a given that the glass will usually be superior to most of the other glass out here. I would not be so presumptuous as to suggest the S2 and any of its glass for the anyone who cannot afford it. That said, not of these MF digitals are cheap compared to most of the 35 digital most non-pros use. $5,000 for Pentax 25MM isn't much less than some of the S2 glass. The alternatives like technical cameras have a specific use and by their nature, are slow working, so they are not a substitute for general purpose MF cameras (Hassy, Phase, Pentax) that can also be handheld, used relatively quickly in the field and, except for the Pentax, are viable studio cameras as well.
If Hartblei could make a lens that approached the resolution and contrast of Pentax glass, and had a smooth, easy mount, it would be an affordable alternative for the occasional use of shift and tilt for MF shooters. Calling Munich - Stefan, are you listening?
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