ondebanks

<blockquote> <p>Are there any other SLRs out there that priced similar to the M645 but in 6x6?</p> </blockquote> <p>Pentacon Six TL. Check Trevor Allin's marvellous site: <a href="http://www.pentaconsix.com/">www.pentaconsix.com</a></p> <blockquote> <p>Bonus points for having lots of ready available parts available second hand.</p> </blockquote> <p>Everything for the Pentacon Six is second hand! Especially plentiful in Europe.</p> <p>Now, I have to dispute or expand on some of Jochen's statements:</p> <blockquote> <p>Soviet Kiev - Maybe go for the Hasselblad lookalike versions but lenses not great & clunky.</p> </blockquote> <p>The original Kiev 88 limits you to Kiev screw-thread lenses. The later/modified Kiev 88cm (and similar under different names such as Arax and Hartblei) have a different lens mount, which takes all Pentacon-Six mount lenses: Schneider, Carl Zeiss Jena, Meyer/Orestegor/Prakticar, and Kiev itself. So I very much disagree with "lenses not great" - the first two of these marques (Schneider and CZ Jena) are uniformly very good, and the others have certain very good lenses in their lineup.</p> <blockquote> <p>Pentacon Six: Known to have issues with film counterpresseur and prone to develop issues with film spacing.</p> </blockquote> <p>I had one of these and liked it. It is extremely light for a 6x6 SLR. The pressure plate issue (a slight bowing forward of the centre of the film) can only be seen in some photos shot wide open. If you get a body with good film spacing and wind it correctly, it will stay good.</p> <blockquote> <p>Kiev clone of it: worse and no Zeiss lenses (worse too).</p> </blockquote> <p>Kiev never made a clone of the Pentacon Six. They made their own 35mm-shaped SLR with the same Pentacon Six lens mount, but it looks, feels, and weighs nothing like the diminutive Pentacon. This was the Kiev 6c. Around the time of the fall of communism, it was changed slightly and the new model was called the Kiev 60. This too has seen some more recent tweaks and rebadging under names like Arax. I had an Arax 60 MLU; big and clunky but it took great photos. I chose it over the Kiev/Arax 88cm Hasselblad lookalikes as it was cheaper and had a better reputation for reliability.</p> <p>Also, "no Zeiss lenses" is incorrect for these bodies. Since they have the Pentacon Six mount, they take all the lenses I listed above, including Zeiss Jena.</p> <blockquote> <p>- Reunified German Edixa same mount, maybe finally OK but nastily priced. - Schneider lenses, the same.</p> </blockquote> <p>It's Exakta, not Edixa. The Exakta 66 to be exact(a!). This is basically a Pentacon Six TL body covered in rubber armour, with new viewfinders, some meter-coupling electronics, and better film flatness. It arrived in the 1980s, actually prior to German unification, with a new range of Schneider lenses - the same ones I said you can also use with the Kiev and Arax bodies (and by the same token, the Exakta can also use the CZ Jena and Kiev lenses, not just the Schneiders). The body was tweaked slightly over 3 variants, Mark I - II - III.<br> <br />All these cameras are lower-tech than even the first generation (all metal) Mamiya 645s; I describe them because you want to have a 6x6 SLR at low cost (although the Exakta will be too expensive).</p> <p>But if 6x4.5 cm format is not a deal breaker, then the Mamiya 645 is a better built, better featured and easier to use camera - much better options in coupled light metering, grips and drives, for example - with a huge stable of very affordable high quality lenses (in the same performance range as the CZ Jena and Schneider lenses). Plus, with a simple adapter, it can also use the Pentacon Six mount lenses - some of which fill gaps in the Mamiya 645 lineup.</p>

<blockquote> <p>From the looks of it the only backs capable of exposures longer than 1 minute are the CMOS censors and some of the newer CCD</p> </blockquote> <p>For longer exposures, the 50MP and 100MP CMOS sensors will be best.</p> <p>The CCD sensors are a bit behind the CMOS ones. Backs/cameras with Kodak CCDs are better in long exposures than those with Dalsa CCDs, and the best Kodak CCDs were those with 6 micron pixels (40MP and 50MP), followed fairly closely by the 6.8 micron pixels (31MP and 39MP), followed less closely by the 9 micron pixels (16MP, 18MP, and 22MP).</p> <p>Phase One engineered the best long exposure performance out of these Kodak CCDs, in their P+ line; but the caveat is that the back takes a mandatory dark frame of equal duration to the photo exposure. Hasselblad and Pentax, also using Kodak CCDs, do not make the dark frame mandatory, so it is left up to you if you want to shoot and apply one, and you can do so in your own time, which is much preferable.</p>

<p>Obviously the shift functionality is unique in the Mamiya 645 lineup (and no other 645 SLR had a shift lens in their lineup) so if you're a regular shift user, it's a no-brainer.</p> <p>I would imagine that it will be a somewhat inconvenient general-purpose wideangle, however. Apart from the increased weight and bulk, two other considerations are that:<br> (1) It does not have automatic aperture control (the shift mechanism prohibits this). You'll notice that the aperture ring is at the front, totally decoupled from the body. <br> (2) As an essentially 6x7 format lens, starting at f/4 and forced to use a highly retrofocus design to accomodate the extra long effective flange distance, it will not hit peak sharpness until about f/8 - f/11; whereas the late (S or N line) 45mm and 55mm wideangles start at f/2.8, and with a smaller 645 image circle to cover and less retrofocus design, hit peak sharpness by f/5.6.</p>

<blockquote> <p>With <a title="" href="http://Keh.com" data-skimwords-word="Keh.com" data-skim-creative="500005">Keh.com</a> - are the film backs ok with BGN or should I go with EX? The body which comes with a WLF - would the focus screen come with it. Also does the A12 come with dark slide?</p> </blockquote> <p>Yes; no need; Yes; and Yes.</p>

<blockquote> <blockquote> <p>you have almost 2 stops less dof with the 645 format than with the d3s full frame sensor<br> I did read somewhere about this but the explanation was a little vague. if you could elaborate I would be appreciated as this is something i am finding looking through the negatives.</p> </blockquote> </blockquote> <p>OK, I'll try to explain it:</p> <p>(1) When comparing two formats, the lens focal length to achieve a given composition scales linearly with the width (or more accurately, diagonal) of the film frame. So 645 (70mm diagonal) requires a lens which is 70/43 ~ 1.7x longer focal length than 35mm film/sensor (43mm diagonal).</p> <p>(2) If 2 lenses have the same f-stop but one is 1.7x the focal length of the other, it also has 1.7x the clear aperture (linear diameter) of the other.</p> <p>(3) However if you could open up the smaller format lens to a 1.7x wider diameter, the two lenses would have the same linear aperture. Each 1.4x change in linear diameter yields a light intensity difference of 1.4 x 1.4 = 2x, which we define as 1 stop [recall how the f-stop scale increments are always 1.4x the previous aperture: f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, ...]. So opening up to a 1.7x wider aperture is a light intensity difference of about 1.5 stops.</p> <p>(4) Like light intensity, DOF also scales as the square of the linear aperture [except in inverse] so it can also be 'measured' comparitively in stops. Thus the 1.7x <em>increase</em> in aperture diameter (645 lens at the same f-stop as the 35mm lens) produces a <em>reduction</em> in DOF of about 1.5 stops. John expressed this as "almost 2 stops less dof". For the bigger medium formats (6x6, 6x7, ...) it equals and then exceeds 2 stops.</p>

<blockquote> <p>Medium film cameras are much cheaper than digital cameras. But i know that someday, i will go for a digital medium format camera. <br /> So what camera should i go for as a beginner medium format camera. It has to have a good light meter, not loud shutter sound , easy in use, if its autofocus, then its very nice.</p> </blockquote> <p>The camera that best meets your requirement is a Mamiya 645AFD. A body which shoots both film and digital backs; has autofocus; is definitely easy in use; has a moderately smart light meter which evaluates the scene in 5 zones, and switches automatically between averaging and spot metering accordingly [or you can set it directly to either averaging or spot]. Less expensive than other medium format film+digital platforms, and has the largest lens ecosystem including manual-focus Mamiya 645 and adapted 3rd party lenses.</p> <p>It doesn't have a terribly quiet shutter, but then no medium format SLR has really - it's their big mirror slap that dominates the sound over the shutter itself. But it's quieter than a Hasselblad, that's for sure. </p>

<p>Any chance that the 80mm lens took a fall between rolls? It could be a misaligned lens element.</p> <p>Another possibility is that maybe your 2nd roll was not fed under the retaining lip when loading it. If you don't know what I mean by this, skip to 2:40 in <a href=" youtube video.</a> It would still be hard to explain why the 50mm shots on that roll look fine though. </p>

<p>The "no Fb" error message is what you get when there is no back at all on the body (the shutter should be automatically retracted in this condition). This error can also arise when the electronic pins on the back are not contacting well with the strip on the body, so the body 'thinks' it is not connected to any back. Try cleaning all the contacts.</p> <p>Also, check that the two protruding latches/lugs on the upper rear of the body are not bent upwards - in my experience even a very slight bend was enough to make the contacts at the bottom mesh erratically. If that's the case, <em>gently</em> bend each lug back to level with a pliers, and it will never give trouble again.</p>

<blockquote> <p>You cannot use 35mm film in a medium format camera without some form of modification.</p> </blockquote> <p>Oh yes you can!<br> It's quite easy to DIY this, at least for certain cameras. I described and photographed what I did to shoot 35mm film, in an <em>unmodified</em> Mamiya Press back, <a href="/medium-format-photography-forum/00V0ri?start=10">in this thread.</a> And it turned out that I wasn't the only one doing such things.<br> <br />Whether there's any point in doing so is the other question. I just wanted to shoot an ISO 800 emulsion which wasn't available in 120 or 220 format. That is probably the only circumstance where it makes sense.</p>

<p>Pages 102-104 of the AFDII user manual cover troubleshooting and the error messages. Unfortunately the advice for codes such as Err 02 is not very revealing - to summarise it: install fresh batteries, and if that fails, use the emergency film rewind and call Mamiya service. </p>

<p>Sanjay, I've bought dozens of used lenses of various marques from ebay - fairly evenly mixed between European, US, and Japanese sellers. In can think of only one case where I got a compromised lens which had not been flagged in the description. If you follow Mike's advice - "Look for high quality photographs of the lens and good complete descriptions" - you should be fine.</p> <p>Joseph, Sanjay said he already buys from KEH.</p>

<blockquote> <p>Mamiya did choose to leave a wasteful amount of space between frames. You ought to be able to get sixteen 6x4.5 frames on a roll of 120.</p> </blockquote> <p>You do get 16 on the Mamiya 645AF(D) line, however. The standard HM401 film backs are self-contained with internal motors - there's no geared coupling to the body - so the film spacing is more tightly controlled than in the older manual focus cameras.</p> <p>However, some users complained that the change to 16 frames increased the chances of the kink (that develops in the film when it sits around a roller for a protracted period) falling within a frame, instead of in the gaps between frames. So Mamiya produced a revised film back, the HM402, which offers the choice of either 15 or 16 frames. These backs appeared with the 4th generation 645AFD III, at a time when most new buyers were getting the body with a digital back instead and the overall medium format film market had shrunk considerably, so they are much rarer and more expensive than the ubiquitous HM401 backs. The HM402s also wind a bit faster and imprint more metadata in databack mode.</p> <p>We had a <a href="/medium-format-photography-forum/00YUob">good thread here about this a few years ago</a>. It illustrates the kink problem clearly and the 15-vs-16 frames debate. Just ignore the combative posts by Q. G. de Bakker.</p> <p> </p>

<p>That was good fortune! Congratulations, and enjoy.</p>

<blockquote> <p>Where does "60,000 electrons per pixel" come from?</p> </blockquote> <p>From <a href="http://www.kodak.com/ek/uploadedFiles/Content/Small_Business/Images_Sensor_Solutions/Datasheets%28pdfs%29/KAF-39000LongSpec.pdf">the CCD's datasheet</a>: Saturation Signal spec. is 60 k e-</p> <blockquote> <p>16 bit word depth has nothing to do with signal to noise ratio. It is the number of steps between black and white.</p> </blockquote> <p>But choosing the <em>minimum </em>number of steps between black and white signal does depend on the ratio of signal to noise - the maximum signal to the minimum noise; which is the saturation signal to the readout noise; which is the dynamic range of the sensor. Find the power of 2 nearest to (but larger than) this ratio, and that power is the minimum number of bits required to digitize any signal while correctly sampling the full dynamic range.</p> <p>Higher bit depth than that (oversampling) doesn't do anything further for signal discrimination, but does resolve the noise levels, which can be helpful in combined/stacked images or combined/binned pixels.</p> <p>All the cameras I am aware of use even numbers of bits in their ADCs (the most common being 10, 12, 14 or 16 bit). ADCs with odd numbers of bits do exist, but don't seem to be used in the photographic industry. So in the example I gave above for the P45+, I referred to 12 bits being the appropriate bit depth, 14 bits oversampling to a generous degree, and 16 bits being overkill. </p>

<p>The fairly accurate rule of thumb is that for equivalent framing on 6x7, use double the focal length you would use on 24x36 mm format.</p> <p>Mamiya appear to have taken this 2x approximation as a literal rule in designing some of their 6x7 lens range.</p> <p>So for example the 210mm APO in the RZ67 line corresponds to the 105mm of Nikon et al.; the 360mm APO (or older non-APO) corresponds to the 180mm ED of Nikon et al.</p> <p>As far as depth of field goes, if you want to keep it matched across the formats - as well as keeping the framing matched -, then if you double the focal length you should also double the f/number. This is just as well, because if you want to shooti wide open, maintaining the same fast f/number on a lens of twice the focal length would be prohibitively expensive and heavy! And it just so turns out that the RZ67 max apertures are about double the Nikon max apertures. For 105mm -> 210mm, it's f2.5 -> f4.5. For 180mm -> 360mm, it's f2.8 -> f5.6 (APO) or f/6 (non-APO). </p> <p>Now if you want to replicate the Nikon 200mm f/2 on 6x7, Mamiya don't have an equivalent, but Pentax do: the 400mm f/4 EDIF for the Pentax 67.</p>

<blockquote> <p>I know that Phase one has 16 bit color but does anyone have any thoughts about Pentax 645Z's color or color tone and image quality?</p> </blockquote> <p>The 16 bit thing is a red herring; it's really just over-engineering; but it makes good marketing copy. The Kodak KAF-39000 CCD in the P45+ can capture 60,000 electrons per pixel, close to 2^16 (= 65,5356), which seems to suggest that a 16 bit output is appropriate.</p> <p>But when you consider that the readout noise is 16 electrons (2^4) per pixel, leaving a dynamic range of 2^16 / 2^4 = 2^12 by the standard engineering definition, then a 12 bit output is sufficient, 14 bit would be oversampling the noise (useful only in certain situations), and 16 bit is completely overkill.</p> <p>The bigger issues here are:</p> <p>1) Colour response: Kodak's colour filter array in the P45+ vs Sony's colour filter array in the 645Z. I've seen nothing wrong with the Sony, but the Kodaks are legendary. I use an old Kodak-chipped back myself.</p> <p>2) Tonality: medium format CCDs like in the P45+ have a "high signal, high noise" characteristic. This gives clean highlights, and film-like grainy darker tones. Like film, they also suck at being pushed to higher ISOs. The Sony sensor is CMOS, which has a "moderate/high signal, low noise" characteristic. This is much better suited to being pushed to high ISO, and gives a better dynamic range at low ISO.</p> <p>But even when these two types of sensors capture a scene at the same signal to noise, it looks different. For example, exposing the CCD at ISO 100, and the CMOS at ISO 400 with 1/4 the exposure time and identical lens settings, might yield similar signal to noise. But high signal in the presence of high noise looks more organic and crunchy than low signal in the presence of low noise, which looks a bit flat and manipulated (looks de-noised even though it wasn't). Signal to noise may be a numerical ratio, but it has both quantity and quality aspects and I frequently point out the latter.</p> <p>3) Size: the P45+ is a larger sensor (49 x 36mm, vs. 44 x 33mm). It's not a huge gap but something to be aware of if you are considering lens crop factors etc. A given focal length wideangle will retain more of its wideness on the larger sensor. The P45+ also has fewer, larger pixels (6.8 microns vs. 5.3 microns) so the demands on lens MTF are a little easier.</p>

<p>Vernon,</p> <p>Thanks to your first two photos - of the flat-edged 120 and milled-edge 220 plates - I just wanted to take the opportunity to point out that they basically also illustrate how the switchable 120/220 pressure plates in some cameras/backs work.</p> <p>A back insert for the Mamiya 645AF(D) line, for example, has a 180 degree rotating pressure plate. It has a pattern of flat and milled strips along the edges, but the patterns on the left and right sides are opposite. The outer guide rails inside the back itself are broken into a complementary pattern of several mm of rail, several mm of a gap, and so on. At the plate rotation for 120 film, the flat-edged strips of the plate sit on the strips of rail in the back. At the plate rotation for 220 film, the milled-edge strips of the plate sit on the strips of rail in the back, and the flat-edged strips of the plate drop into the gaps in the rail, so the whole plate sits further forward. It's a clever system.</p>

<p>Anthony,<br> I suspect that you already provided the answer when you wrote this:</p> <blockquote> <p>They release the lens with the body release with their finger which will close the shutter blades and release the mirror up.</p> </blockquote> <p>...the point being that it reads like it's a pin/lever on the RB67 <em>body </em>that closes the shutter. Your lens board probably does not replicate that particular mechanism of the body?</p>

<blockquote> <p>maybe for infrared?</p> </blockquote> <p>Infrared focus goes in the other direction - "inside" visual-light infinity, not beyond it.</p>

<blockquote> <p>how can i insert image from pc?</p> </blockquote> <p>When you are writing a post, do you see the little icon at the top of the editing box, that looks like a green tree? Click that and enter the URL for an externally-hosted image. </p>

<blockquote> <p>You could try using the stop down lever and taping it in the iris closed position then use the aperture ring to change the apertures.</p> </blockquote> <p>This works. I do exactly this with RB67 and RZ67 lenses when I use them on my Mamiya 645AFD. There's no need to mess with T mode or mirror-up mode; you can just leave the lens shutter permanently cocked and hence always open (although this is probably not ideal if you intend to use the lens on an RZ/RB camera at some future date).</p> <p>I easily made my own RZ/M645 adapter with a focusing helix for this purpose: <a href="http://www.getdpi.com/forum/medium-format-systems-and-digital-backs/55563-rz67-rb67-lens-adapter-mamiya-phaseone-645-camera-diy-100-a.html">see my article on getdpi.com</a></p>

<p>I have only encountered two versions - yours with the filter set you listed, and mine with an amber warm-up "LB-A(81C)", clear "SL-1B", yellow "Y48(Y2)", and orange "056(O2)", in that order. I leave mine on SL-1B virtually all the time.</p> <p>So two filters are different between these lens variants: UV & LB-B, vs. Y2 and O2. I would think that the UV and SL-1B filters are very similar? Is the LB-B a cool-down filter, like an 82C?</p> <p>I don't know about manufacturing dates but the serial numbers might be a clue, assuming they change sequentially with date: mine starts with 105xx.</p>

<blockquote> <p>I bought my RZ67 II used and it came along with a Phase One adapter for Hasselblad V.</p> </blockquote> <p>Well Peter has a Pro IID, not a Pro II. <a href="https://www.phaseone.com/en/Search/Article.aspx?articleid=1123&">As this article explains</a>, the Hasselblad V adapter plates are incompatible with the IID, unless the camera is sent away for modification. </p>

<p>Your options are limited to a Mamiya/Phase 645AF mount back [the brand could be Phase One, Leaf, Mamiya, Sinar etc. as long as it has the 645AF interface]. You will also need a HX701 645AF-to-ProIID interface plate.<br> Such a setup does not need sync cables between the lens and digital back; the back is controlled digitally through the interface plate.</p>

<p>Here is an early test of a replacement UV/IR block filter for my Kodak DCS645M. I learned in recent months that this old digital back <a href="http://www.getdpi.com/forum/medium-format-systems-and-digital-backs/54973-kodak-dcs-pro-back-645m.html#post656609">has a big following in Russian circles </a>and they have reverse-engineered many important things in the firmware etc. They also determined the exact filter specs; it turns out that the German company Astronomik make filters for astronomers in exactly the right 50x50x1 mm dimensions. The Kodak filters are designed to be easily removable, with a click-in holder. I damaged my original one, and the Kodak replacement filter I've been using since 2011 has an earlier cutoff in the red part of the spectrum. So when I had the opportunity to buy a discounted, as-new <a href="http://www.astronomik.com/en/photographic-filters/luminance-filter-l-1-l-2-l-3.html?limit=30">Astronomik L-3 (UV/IR block) filter</a>, with a response extending past 660nm like my original filter, I took it.</p> <p>So far, I'm very happy with its high and broad throughput - as the pic shows, it certainly passes the red nebulae (656 - 658 nm) test; look at Orion's sword and belt.</p> <p><img src="http://imageshack.com/a/img907/5443/wEPlPF.jpg" alt="" /><br> <strong>Orion: 80/1.9 at f2.8, Mamiya 645AFD, Kodak DCS645M at ISO 400, 1 minute tracked exposure.</strong></p>