6x7 compared to 645?

stradibarrius · Nov 24, 2009

It the main advantage that 6x7 has over 645 is the ability to produce larger prints?
I have a RB67 and a Mamiya 645 so this is an honest question and not an attempt to start awar...LOL!

David A. Goldfarb · Nov 24, 2009

6x7 has more film real estate, so yes, you can make prints with more detail, whether they are larger or smaller.

645 is more compact and can be a better choice if you need long lenses.

Joachim_I · Nov 24, 2009

The aspect ratio of 6x7 is 4:5, the one of 645 is about 4:5.4. This could matter if you want to enlarge to a certain paper size (like 8x10, 4:5 ratio).

keithwms · Nov 24, 2009

The differences that really matter, IMHO:

*645 offers *much* faster lenses. There is only one truly fast lens in the rb/rz lineup, the 110/2.8. By comparison, almost every 645 lens is 2.8; some are faster. If you want to do available light work on moving subjects, then the question you have to ask yourself is: would you rather shoot ISO 800 at f/2.8 or ISO 1600 at f/4, working with no focus confirmation through a darker lens....

* 645 also offers much longer lenses... affordable even. A 300/2.8 manual is about the same price as the comparable lens for a leading 35mm system.

* ... on the flip side, 6x7 works way better for me for wider shots. There is only one ultrawide in the mamiya 645 lineup and it is very costly. The 35mm is nice but... if wide is your thing, the rb or rz will delight.

* the rb/rz systems are bellows focusing... a huge advantage for closeup and macro. Yes there are extension tubes for 645 but if you want to precisely control your magnification, bellows are very helpful

* Some of the 645 systems provide focus confirmation; the rb and rz do not. For some photographers, this is a major issue. AF is moot for me, the AF isn't really much to speak of unless you go for the really new and pricey models like the afd3.

* the rotating back on the rb/rz is also a huge convenience, especially when using the 6x8 back. Honestly, to me, *the* major operational weakness of the mamiya 645 systems is that shooting in portrait format is a hassle... even with a prism or with a newer afd. There are no vertical grips (which I really miss from 35mm gear) and , wouldn'tcha know, I really like portrait format. No problem, mamiya has designed a godawful rotacam bracket that you can schlep to do verticals more conveniently!!! :rolleyes:

So... big differences in lenses and overall handling make these two systems very difficult to compare. I have both, I use both very happily. To complicate matters even more... there is the mamiya 6/7/7ii which also brings totally different strengths to the table. So I will conclude with this observation: the major strength of MF is the gear diversity... RFs, SLRs, TLRs, view cameras.... Enjoy that diversity.

sanking · Nov 24, 2009

Bear in mind that the magnification factor is more important than total film area in determining final print quality. Although the 6X7cm negative has almost twice the total film area as a 6X4.5 negative (nominal 42 square centimeters versus 23 square centimeters), the actual magnification needed to make a print with the same long dimension is only about 15% more for the smaller negative.

In other words, print quality would be about equal in a 30X35" print from a 6X7cm negative, 22X30" from a 6X4.5cm negative, and 30X30" from a 6X6cm negative.

In the final analysis lens quality and camera handling are much more important than which of the three formats you use.

Sandy King

stradibarrius · Nov 25, 2009

I was more curious about the format rather than the cameras. If 8x10 or 11x14 are as big as you typically, enlarge does the larger negative of the 6x7 hold a significant advantage.
It goes with out saying that the M645 is much more manageable than my RB67 but the rotating back of the RB is a real advantage. I am not planning on giving either up I am just trying to increase my understanding of the formats. Learning the strengths and weakness of each. I see me using both of these cameras where I, personally, hardly ever use my 6x6 camera even thought is takes excellent photos and is light and easy to use. That's why I have it for sale but not my RB or my newly acquired M645.
But the additional information is valuable and I do appreciate it. If there is more I am certainly interested in that as well.

georgecp · Nov 25, 2009

Since you already own both systems, the best way to get an answer to your question is to try it for yourself. Make an exposure with your favorite film/lens in each system and then develop and print at your largest typical print size.

Look at the prints.....the subtle differences in tonality, ambience are as important (or maybe more important) than specific attributes of grain/sharpness. leave the prints on a wall for a while and look at them.......you will soon have your answer if the camera handling tradeoffs of these systems are worth the difference in print quality. Your answer will be concrete and more valuable for you than any answer on this forum.

martyryan · Nov 25, 2009

If you are enlarging to 11x14 and smaller you should not notice a difference in print quality between a 645 and 6x7 neg.

Marty

Christopher Walrath · Nov 25, 2009

Not to mention, the 645 format tends to be closer to a 35mm neg in dimension and the 6x7 format is really close to square if that's you style.

Jeff Searust · Nov 25, 2009

I use a 6x4.5 back on my RB-67 also...

Rudeofus · Nov 25, 2009

sanking said:
Bear in mind that the magnification factor is more important than total film area in determining final print quality. Although the 6X7cm negative has almost twice the total film area as a 6X4.5 negative (nominal 42 square centimeters versus 23 square centimeters), the actual magnification needed to make a print with the same long dimension is only about 15% more for the smaller negative.

Not trying to nitpick, but the difference is higher. The long side of a 645 slide/neg is 56mm, whereas it's 69mm for the 6x7 format. This means the difference is 23% in linear direction or over 50% in area. And this is only the worst case scenario, for any other aspect ratio the increase in area will be as high or higher.

MikeSeb · Nov 25, 2009

I think Sandy and Christopher have hit on the bigger differences for me. Yes, the 645 has 27 sq-cm area vs. the 42 of the 6x7, and it makes a difference. But I think overall my Contax 645 images are the best MF images I've made, about equal to the Mamiya 7, but superior to the RZ67---the difference being the ergonomics and stability of each as a hand-held platform.

Withal, I've come to like the more-nearly-square aspect ratio of the 6x7 more than the slightly more rectangular shape of the 645 images. It seems the 6x7 lacks that little bit of image I was always cropping out of my Contax frames.

keithwms · Nov 25, 2009

Personally, I don't get the arguments about cropping and filling the standard paper sizes etc. I usually print squares when I shoot 6x6; I usually print 6:4.5 when I shoot 645; I make 5x7 contact prints when I shoot 5x7 etc.... It's not a boast that I rarely crop- I simply find it annoying to compose for an aspect ratio different from what I see in my VF or on my ground glass.

When I got my first 6x6 rangefinder, I admit that I did so because I had read all about how lovely it was not to have to turn the camera sideways when going between vertical or horizontal orientation. But with 6x6 I quickly had a helpful epiphany: gee, squares work, they really work! So I just haven't given a fig about standard paper sizes since then. Moreover, I have long had the feeling that squarer compositions are more about balance and a feeling of established placement. The more rectangular ratios (645 and 35mm) usually seem, to me, to favour motion in the frame.... subjects going somewhere, either literally or by figurative connection.

I also think the issues of how large a print can/should go and how much one can crop is basically pointless. That's always going to be a personal thing, as personal as the artistic motive itself.

Joachim_I · Nov 25, 2009

keithwms said:
Personally, I don't get the arguments about cropping and filling the standard paper sizes etc. I usually print squares when I shoot 6x6; I usually print 6:4.5 when I shoot 645; I make 5x7 contact prints when I shoot 5x7 etc....

But that's exactly the point! You can enlarge a 6x7 negative to 8x10 or 16x20 paper without wasting paper. If you want to enlarge a full size 645 negative to 8x10 you need to cut away some paper. Actually, this is the very reason why 6x7 exists.

I still have an old article written by Paul Klingenstein (ex chairman of Mamiya): "How 6x7 became the Ideal Format. Recollections of an Old-Timer." In this article, the author describes that the US army was asking for a roll film camera during WWII which delivers the same aspect ratio as 4x5 field cameras. The reason was exactly the one I mentioned: enlarging without waste of paper to the then standard 8x10 paper format. This camera was then developed during WWII by the Simmon Brothers (brand name Omega). It was introduced to the civilian market in 1954. This was the birth of 6x7! Linhof followed in 1960 with their slightly longer 6x7 format (72mm long), Pentax came out with their 6x7 SLR in 1969 and Mamiya with the RB67 in 1970. Many other 6x7 cameras were introduced later, including the latest model, the recently introduced Bessa III.

I am not saying that wasting some paper or not is an important consideration for everyone. But it could be for someone. Obviously, it was a relevant reason for the US army.

I chose 6x7 because I wanted the maximum format for which I still can get a slide projector (yes, I know, Noblex made a slide projector for 4x5 sheet film, but this is a rather exotic machine).

sanking · Nov 26, 2009

6X6cm format does not work for me and if I am shooting 6X6 it will always be my intention to crop. That being the case, 6X4.5cm or 6X7cm format makes more sense for my work since it is a more efficient use of film. In fact, for most work I generally find the aspect ratio of 6X9cm more pleasing than either 6X4.5 or 6X7 and I will often crop to that ratio for printing.

It is extremely rare for me that the format I am photographing with has the perfect aspect ratio for my vision of the scene, irrespective of what format I have on the camera. I almost always want to adjust the aspect ratio later in printing or after scanning. However, most of my printing is done to the aspect ratio of the 6X9cm format, regardless of what format I actually use to make the negative.

Sandy King

wiltw · Nov 26, 2009

Joachim_I said:
The aspect ratio of 6x7 is 4:5, the one of 645 is about 4:5.4. This could matter if you want to enlarge to a certain paper size (like 8x10, 4:5 ratio).

Both the Mamiya 645 and Pentax 645 have 56mm x 41.5mm frames, but the Bronica ETRS is 55 x 42mm.

The Mamiya RZ67 is 69.5 x 56mm, so even it is not a perfect 4:5, nor is the Pentax 67 with 55 x 70mm frame.

Sniggling points, nevertheless, especially if you consider the fact that you compose in the viewfinder which probably is not showing 100% of the area. That, and the fact that the mask in the enlarger crops down the full frame, too!!!

Q.G. · Nov 26, 2009

sanking said:
6X6cm format does not work for me and if I am shooting 6X6 it will always be my intention to crop. That being the case, 6X4.5cm or 6X7cm format makes more sense for my work since it is a more efficient use of film. In fact, for most work I generally find the aspect ratio of 6X9cm more pleasing than either 6X4.5 or 6X7 and I will often crop to that ratio for printing.

Given the minimal difference in image quality, it could be argued that cropping 6x6 instead of using 6x7 is the more efficient use of film.
Yes, there are used bits that are cropped away. But you still get more images to the roll than on 6x7.

johnnywalker · Nov 26, 2009

Q.G. said:
Given the minimal difference in image quality, it could be argued that cropping 6x6 instead of using 6x7 is the more efficient use of film.
Yes, there are used bits that are cropped away. But you still get more images to the roll than on 6x7.

Extending that argument, 35mm is an even more efficient use of film.

2F/2F · Nov 26, 2009

The main advantage is more magnification at a given angle of view, which translates into less magnification of the film to achieve a given print dimension. Whether this makes a difference to you in your situation will depend on what you want to have in the end.

I find enough difference between the two that on a trip, I usually shoot 35mm, 645, and 6x7. I use each for different sorts of things. I use 6x7, almost always on a tripod, when I have the most time and want the best "quality", in the classic technical sense of the word. I used to use 4x5 for this, but got an RZ so I don't have to haul the 4x5 as often, so shooting is cheaper and more convenient on the road, and because it opens up all sorts of great emulsions that are not available in sheet sizes (mainly Reala, Pro 400H/NPH Pro 800Z/NPZ, and Delta 3200). When I can manage a fast shutter speed for what I want ('250 or faster using the 110 lens, and '125 or faster using the 65mm lens), I don't have any qualms whatsoever about using the 6x7 hand held, based on printed results that I have obtained. I use 645 to shoot somewhat similar subject matter as I do with 6x7, but when I have less time, or envision a smaller and/or lower "quality" print. I will more often use the 645 with a fast film, hand held (or in the RZ's role when I have not bothered to bring the RZ). I use 35 for its many advantages over either of these alternatives for certain subject matter, and for its aesthetic qualities, which are unmatched by larger formats.

sanking · Nov 26, 2009

johnnywalker said:
Extending that argument, 35mm is an even more efficient use of film.

And extending the argument just a bit more, digital is 100% more efficient than any size film.

Sandy King

Jerevan · Nov 26, 2009

Size does not matter, it's more interesting to care about what you are pointing the camera at.

keithwms · Nov 26, 2009

Wellll..... 6x6 makes the best use of the image circle 35mm... tsk tsk, think of all that wasted circle... :rolleyes:

Anyway, obviously these things boil down to personal preferences. Let us just take a moment to think about how many different options we've had here... and how few options there are in digital.

One last point: size does matter very much sometimes. It matters if you want to contact print; it matters if you like to visualize the subject at roughly life size as opposed to some teeny tiny version through a keyhole; it matters if you want to make use of certain processes and lenses.... overall, it matters for reasons of art, not just technique.

markbarendt · Nov 26, 2009

keithwms said:
Personally, I don't get the arguments about cropping and filling the standard paper sizes etc. I usually print squares when I shoot 6x6; I usually print 6:4.5 when I shoot 645; I make 5x7 contact prints when I shoot 5x7 etc.... It's not a boast that I rarely crop- I simply find it annoying to compose for an aspect ratio different from what I see in my VF or on my ground glass.

I'm with you exactly Keith,

The more I play with different formats and lenses, the more I compose with what I can see in the camera and a good composition is possible in most settings with most formats.

Regardless of format, cropping changes the edge effects. For my new RB the next lens I plan to get will have the floating element adjustment. I actually hope to use this adjustment to defocus the edge more, once that's done it would be a shame to trim that effect away.

markbarendt · Nov 26, 2009

keithwms said:
One last point: size does matter very much sometimes. It matters if you want to contact print; it matters if you like to visualize the subject at roughly life size as opposed to some teeny tiny version through a keyhole;...

This is one thing that I'm really finding now that I'm shooting MF and LF. 35mm is way convenient but 6x6 plus sure makes picking what negatives I want to work with easy, with smaller stuff I tend to miss things like somebody blinking until I've spent the time to get it in the enlarger or get the print back from the lab.

HiNDri · Nov 26, 2009

sanking said:
And extending the argument just a bit more, digital is 100% more efficient than any size film.

I love it when an some one extends an argument to its irrefutable conclusion.

I've been going back and forth between 6x6.45 and 6x7 as I struggle to decide how to enter MF film. I find in my digital work with a 17 mp full frame camera that I regularly crop to "non-standard" sizes. I've never been bound by what size a picture is "supposed" to be. This does waste paper in printing but I off-set that somewhat by doing my own matting and framing work. I haven't actually developed or printed film in decades, but my memory is that cropping is considerably more complicated with an enlarger and photo paper. Is it the sense of this group that working with the whole image is the way to go with MF negatives or do many of you crop and what not?

Robert

6x7 compared to 645?

Moderator

Privacy & Transparency

Privacy & Transparency