Differences between RB67 & 645

[beth_hamilton]

<p>So I know this has been asked, but none of the posts really answered what I'm looking for... as you may have seen, I have posted before, and I am considering the two above Mamiya's, as a university student (and I would keep it in the future, so it will have longevity) I will be using it in studio, but also on location. I've tried looking at the specifications... but as someone who's reasonably new to MF, I can't tell a huge difference between the two, aside from the obvious of negative size. Is there any quality difference? Or function difference? Also, which am I most likely to be able to get a digital back for in the future?<br>

Thank you!</p>

[markbristol]

<p>Hi Beth,<br />If you plan to shoot film only the RB is the way to go. The neg size makes for extraordinary enlargements. If you plan to use a digital backs in the future the 645 is the logical choice. The reason is that sensor sizes of digital back come closer to the full-frame 645 size than the 6x7 size whick means that wide angle lenses are still wide on the 645 and closer to normal on the RB. The best 645 system is of course the AFD. Later bodies were designed with digital in mind. Keep in mind too that the 645 AF system will probably carry it's value longer but the RB system has rock bottom prices on auction web sites. Hope this helps.</p>

[tmcleland]

I would venture to say that they are so reasonably priced, you could just about get both!

 

Beyond the obvious, I would say the 645 is going to handle more like what you're used to in a 35mm/digital SLR, while the

ergonimcs of the 67 are notably different. The 645 is faster from a handling standpoint, but of course at the expense of the

larger frame size afforded by the 67. However, you are getting 15 frames per roll as opposed to 10 with the 67 so fo

course you'll use less film.

 

As noted, if you're planning on going to MF digital at some point, a 645 AFD Is going to make the most sense. But if your

focus is going to center around film, I would go the 67 route, especially if you have a decent digital rig already in place

(like a Nikon or Canon setup). Remember that, while MF equipment has become very accessible price-wise, digital backs

are FAR from affordable, so until that changes, I would say take full advantage of MF film by getting the best and most

detailed photos that film can give you.

 

Like I said though, you can just about get BOTH, and decide what fits best from there.

[tree]

<p>Hi Beth,<br>

I don't know if I'll be able to answer all of your questions, but being a regular user (and rabid fan of) the RB67 and having started my foray into MF with a Mamiya 645 I'll answer as best as I can.<br>

The RB67 is big and heavy (between 6-7lbs with 140mm macro lens, 120 back, prism finder, left-grip, lighter with the waist-level finder). While you can hand-hold it (see a recent thread on this) some people find this very uncomfortable. If you are going on location and need to carry around the camera and its accoutrements (multiple backs, multiple lenses, perhaps both waist-level and prism finders, filters, film, tripod and head, etc.) this can be an issue. (To get a feel for the size, my 'portrait' in my account shows me with my Beast.) There are digital backs for both the 645 and RB: I suspect they will be made for a long time to come (though if you want to be sure get an RZ instead, since this is a more modern body.) The RB is fully manual: you'll need an external light meter (there is a metering finder for it, but I don't have one and generally trust my hand-held meter). The rotating back is a big plus for me, especially when I'm in the field. As for longevity, my RB was made in the mid-1970s. Mamiya made the model from 1970 through 1990 or so, and if you get the Pro-SD it can mount the newer KL lenses.<br>

The 645 is smaller, weighs less (probably almost half as much), and doesn't have the rotating back. It is going to be much easier to use out on location, especially hand-held. The 645 manual lenses are compatible across the systems (IIRC), including on the 645AFD.<br>

The glass is equally good on both systems.<br>

Good luck, and have fun.</p>

 

[john tonai]

<p>The earliest Mamiya 645 system only used film inserts, not interchangeable film magazines. This means that you cannot change film mid-roll and you cannot put on a digital back. All the others had interchangeable backs. AFAIK the lenses for the different systems are compatible so you could start into the 645 system with the original system and upgrade when you get more money.<br>

One problem with the 645 system is that it uses a focal plane shutter. While there are a couple? lenses with leaf shutters in them, it is extremely limited and if you are going on location and trying to balance ambient light with flash, you don't have a lot of flexibility.</p>

<p>Digital backs come in sizes similar to the 645 format-there are many variations in size, but this is an approximate guide. Because of this, the 645 lends itself to the digital conversion without much problem. The 6x7 size of the RB/RZ is much larger and you would need to put a template in the viewfinder to see the reduced size of the sensor.</p>

<p>The RB is not the best system to use with digital. If you are going with the quality of the medium format digital back, exposure is extremely important and the mechanical shutters in the RB system can be inconsistent enough to be frustrating. Also, since the shutter timing mechanism is in each lens, you need to either compensate for each one manually or get them all calibrated to the same standard-not a cheap, nor easy thing to do.</p>

<p>As an alternative, the RZ system uses an electronic shutter timing mechanism in the body (the shutter itself is still in the lens). This gives you sync speeds up to 1/400th of a second (although that speed tends to be a little generous) to balance ambient with flash.</p>

<p>Also, the RB/RZ system is much better if you like to shoot with the waist level finder. While you can get a waist level finder for the 645 systems that have interchangeable finders, they only work in horizontal format. The RB/RZ allows you to rotate the back (RB=Rotating Back) to change from vertical to horizontal.</p>

<p>You could buy an RB 67 Pro SD This was the last of the RB line, then when you make the change to digital you could get an RZ body. But if you do this, the lens shutter situation will be the same as I mentioned above.</p>

<p>It can take all the lenses made for the RB line, but the lenses made specifically for this camera were optically better than the older ones. The line of lenses built for the first two series of RB cameras can fit on both the RB and RZ. The later lenses (KL) only fit on the the Pro SD and all the RZ cameras. The mount is the same on all the cameras, but the rear element housing is larger on the RZ and the Pro SD cameras. RZ lenses will not work on RB cameras</p>

<p>The RB cameras are mechanical so they don't need batteries to operate. The RZ's are electronic. But the electronic shutters are more accurate so it is actually a better thing. Some old school mechanical camera lovers say that mechanical is better because if you use an electronic camera and your battery dies you can't shoot. The RZ shoots at (I think) 1/90th of a second and Bulb in mechanical mode. If you are shooting in a studio with controlled light, you can operate the RZ in it's mechanical mode by taking the battery out of the camera since you will be adjusting exposure with the lighting and aperture.</p>

<p>Lastly, the RB requires two steps to cock the shutter and advance the film, while the RZ only requires one. This can make the RB much slower to operate than the RZ or the 645.</p>

[gregory_king1]

<p>All good comments. I have the RZ and the 645AFD and a digital back I can use on both of them. In short, using digital on the RZ is tough...I suspect it'd be near impossibly difficult on an RB. I'm not familiar with the issues shooting digital on a manual 645, but I presume it's not worth trying either. So I'll compare the RZ and the 645AFD only. :-)<br>

You get 1/400 sync speed and allegedly better optical performance than the 645, which is limited to 1/125. Plus, you can roll the back rather than tilting the camera to shoot portrait, and use the WLF. So, shooting studio type shots, especially outdoor portraits in bright light, may lend itself to the RZ. <br>

But the crop factor is huge, the weight of everything is huge, and shooting ISO50 on digital pretty much means 1/125 sync gets you to f/8 or f/11 in daylight already. So the penalty for getting to f/4.5 or f/5.6 is huge. Plus, the hassles of MLU and triggering the lens after triggering the back, and manually changing flash power with aperture is a hassle.<br>

With 645AF/AFD, you get auto focus, auto exposure, auto flash control, and auto film advance, all in a light package. Plus, the manual focus lenses are cheap, AND can be used on a digital SLR with the proper adapter. So you could get a FF DSLR for less cost than a digital back. I use a 24x36mm 11mp tethered back, and the performance is phenomenal. Its lack of AA filter keeps me from spending the money on a FF DSLR, even given its hassles.<br>

Hope that helps...<br>

Greg</p>

[stwrtertbsratbs5]

<p>The 645 has a focal plane shutter, so flash sync speed is very slow (1/60 if I recall correctly for the 645 pto TL). That may not be a problem in the studio, but it is limiting if you plan to use fill flash outdoors. That said, there are a few leaf shutter lenses available for the 645 that allow sync at all speeds, but it's a kludge - both shutters trip so you need to be certain to set a long exposure o the focal plane shutter.<br>

I prefer the Bronica ETRSi for 645 myself because all of the lenses have leaf shutters. There aren't as many around, but the prices are low.</p>

<p>Don't worry about buying a camera that will take a digital back if you're a student. Just shoot film for now and save a lot on $$$.</p>

[jack_welsh]

<p>Agree with most of the above. Except about the KL lenses only fitting on the Pro-SD model. Have a 127 KL lens mounted to my Pro-S at this time. Have both the RB and the 645 Pro. Both are great cameras. The 645 is my bigger than 35, but with the 35 feel camera. The RB is great when larger negs are needed. The RBs have built in closeup capability. The 65 does not. Also, being an eyeglass wearer, The RB's WLF is easier than the 645 prism finder. The RB is manual, the RZ is more electrical. But, to me that means that the RZ has more things to break down.</p>

[john_a5]

<p>Just a note, having had many different Mamiya systems including the RB, RZ, Mamiya 7, but do not buy the 645af! Now someone has said that they upgraded the lenses, but I had more problems with the system and found that when I scanned the negs at higher dpi they just sort of fell apart. I do understand that the 645Pro has much better optics.</p>

<p>I will say that if I were to buy one of Mamiya's system today, it would be to go back to my first, the RB. I like that it is all manual and for studio and considered outdoor work, I don't mind the external metering or manual settings.</p>

[gregory_king1]

<p>The 645 Pro has much better optics than the 645AF? I find that hard to believe. Especially since all 645 Pro lenses (manual focus), short of the leaf shutter lenses, can be used on all 645AF bodies.<br>

The 645AF also offers focus confirmation on all manual focus lenses, but a good MF split-prism screen may do a better job of it.<br>

I can see no difference in IQ between my AF and MF lenses.</p>

[john_a5]

<p>Gregory, what size scans do you do? Both of my 645AF's had to be sent back to the factory when new because they couldn't focus the normal to long lenses, wides were fine. Aftr that, doing 60mb scans, all looked great and i loved the camera--nice size and weight. But then I had a job where I needed to scan at 150mb and the images fell apart. The focus was not consistent and fell off quite a bit at the edges. There were other odd things that also showed up at that size. I tested the lenses and compared them to other systems, including the V (which I had) and H Hasselblad systems. I replaced it with a Hasselblad H system and they are not even in the same ballpark.</p>

<p>I talked to folks at the pro store I used and they indicated that the MF lenses were much better than the AF lenses. It might be that the new AF lenses are better--I spoke to a rep who seemed to admit that the older lenses were not that great but said they had redesigned some of them.</p>

[gregory_king1]

<p>John,<br /><br />Interesting. So that's a camera problem, not a lens problem, right? <br /><br />My scans are quite lacking...using the V500 I can only get 2400dpi according to commonly accepted belief. And even then...I wouldn't be able to see much at the edges anyways....I shoot only portraits, so the edges are never in focus.<br /><br />Comparing MF to AF, I can't say I've compared the same lenses head to head. I guess I have to to be fair, but can only do it on my digital back which will crop out the edges anyways. I have compared the 55mm MF to the 35mm 1.4 Sony, both on cropped 11/12mp sensors and the MFDB won hands down. Probably due to sensor differences, though.<br /><br />I have the 55 AF now and could compare the two, but feel little need. I used it for this shot, and it is pixel sharp (also from the MFDB).<br /><br />The newer lenses are reportedly sharper still as you mention. Maybe I'm just not picky enough, or maybe I just thought all my blurry photos on improper focus/too shallow DOF. You mean it might be the gear? ;-) Nah, I can't use that excuse. I think I've checked most of the glass on the MFDB.<br /><br />A lot of guys over on getdpi.com use 645AF and I've never gotten the sense that the older AF lenses are lacking. The new ones they have no problem using wide open.<br>

On a related note, I compared the 110mm RZ67 to 110mm 645 MF and could see no meaningful IQ benefit to the RZ <em>on the same cropped sensor. </em>The images looked "different", possibly due to distortion/perspective, even though I tried to make them look identical.<br>

Now, the fact that they looked different may be indicative enough that something is going on, and it may be more noticeable on uncropped film.<br /><br /><img src="http://gregandlexi.com/photos/2009/09sep/images/BZ000192.039634.Capture.tif_39634.jpg" alt="" width="998" height="1500" /></p>