What are the Pros and Cons to Using a 6x12 Back on a 4x5 Camera?

[steve williams]

I would like to look into some 6x12 camera options. I've seen

references to using a 6x12 back on a 4x5 camera, but saw one posting

by a gentleman on this forum stating that it yields less than

desirable results. He said the pictures turn out a bit soft and that

instead you should use a dedicated 6x12 camera.

 

That's the only reference I've seen to that issue. Can anyone tell

me if that is indeed a good option or if I should forget the

rollfilm back on a 4x5 camera option?

 

Thanks for any help,

Steve

[geoff_mcauliffe]

You don't need a 6x12 back to shoot 6x12 in a 4x5 camera. Draw some crop marks on the ground glass and compose. Or shoot the whole frame and crop as desired when printing. A lot cheaper than a back or a whole camera.

[neal_shields]

I think film flatness issues with 6x12 backs may be more serious with some types of photography than others.

 

It is all "like triangles". If for example you are using a 150mm lens and are 15 meters from your subject then you are 100 times the distance from the subject as your focal length. Any film flatness error will shift your point of focus 100 times. If for example the middle of the film is standing away from the back plate 1 mm, then your focus will be off by 100mm at the subject or 4". However at that distance depth of field will more than cover the error.

 

If you are focusing on a bride's eyes at 3 meters then a 1mm error in film flatness will shift you focal point less than 1" and again I suspect you wont have enough resolution in most enlargements to see the difference. Especially with 300 dpi digital prints.

 

I also don't understand why a large format roll fill back costing over $1000 new, wouldn't be more likely to hold film flat than a dedicated camera?

[david_goldfarb]

I think it would depend on the choice of back and how well the camera is adjusted. The lenses are typically the same, and a 4x5" camera is generally a more versatile thing than a 6x12 camera.

[eric rose]

One advantage is that you will probably be able to buy MF film longer than LF is around. Sad but true.

[neal_shields]

Eric:

 

The immanent demise of large format film is probably why Schneider just spent a fortune designing, tooling and releasing a new line of lenses that are useless for roll film.

 

Not to mention all of the people going into the large format camera business and all those already in the business that have back orders measured in years.

 

About a year ago, one manufacturer stopped accepting orders at all till furthar notice.

 

It should also be kept in mind that sheet film is very very easy to make. Photographers were coating their own film over 100 years ago.

 

If the big plants shut down there will still be sheet film. Expensive maybe, but how many of us couldn't stand to be a little more contemplative before we click the shutter.

 

http://schneideroptics.com/photography/large_format_lenses/super-symmar_xl/

[beepy]

Wow, that is wandering off topic. But, I actually (personal navel gazing opinion) felt large

format sheet film would be around for a long time, perchance longer than medium format

film. I would be really interested in seeing film sale drop rates by format... my suspicion is

large format is dropping more slowly.

<p>

Back to the question - a reason for putting a medium format back on a 4x5 camera is to

get the full range of camera movements with medium format film. If that was part of

question

being asked. But 6x12 panoramic format - if for landscape camera movements not so

critical? If camera movement are not needed, using a 4x5 camera to get to 6x12 medium

format is a heavy way to go. If you have a 4x5 camera, then you're used to the luggability

issues.

<p>

Steve? What do you want to do in 6x12 format?

[b_kosoff]

I use a 6x12 back, the Sinar zoom. i have one for normal and one for push,

or a different film. The better backs like the sinar, keep the film pretty flat, the

bad roll film backs don't. If you are shooting landscape with a view camera,

you are most likely to be foucusing at distance or even infinity. You are also

likely to be using apertures like f16-f22. At those distances/aperture your

depth of focus is likely to be as much as 2.5 mm, more than enough to

compensate for film flatness problems.

 

Two things more likely to cause poor focus with a rollfilm back is the weight of

the back causing a flimsy standard to tilt and pop out of focus. The other

problem is when a photographer leans on the GG with their magnifier and

actually ends up focusing in the wrong spot because they moved the rear

standard with their own weight while focusing.

[david dutchison]

There are a couple of problems I can see.

 

LF lenses trade resolution for covering power (Super-high resolution not being needed for the amount of enlargement LF negs are subject to). In most cases your MF lenses will be sharper, and the fellow selling the back has discovered this.

 

Lens and back movements generally become less needed as the focal-length goes up (the exception being macro-photography). Trouble is that your "standard lens", around 135mm for 4x5, is a short tele in the MF world. 90mm is a wide-angle in LF, and a 47mm is a super-wide. To get any range of movements with either of these lenses, you'll need a bag-bellows on your LF camera.

 

Assuming the back has no registration or film-flatness problems, and you're using the absolute best quality LF lenses ($$$$$$$!), this setup might make sense for still-lifes, product/macro photography, and with bag-bellows, architectural photography.

[jan_brittenson]

There's a rather substantial difference in size, weight, stability, durability, and ease/speed of use between a 4x5 field camera with a 612 roll film holder and say a Horseman SW612. You can put the latter on a Gitzo 1228 with an acratech ballhead, throw it over your shoulder and go hike down a ravine. If you bump it, no big deal, while 4x5 standards get warped and damaged -- unless you go massively up in price, quality, and other negatives like weight (e.g. Arca-Swiss Metrics). No bellows to flap in the slightest wind to induce blur. Zone focus based on scale instead of a dim groundglass. No separate roll film holder. Quick and easy one-handed film loading. You can carry 10 rolls of film in a pocket without problems.

 

Basically, a 612 camera has all the benefits of a medium format rangefinder for field use, while a 4x5 has the benefits of a view camera: movements, sheet film, etc. If you're not using movements and are expecting to run roll film through it, and expect to do so in a rugged environment, get the 612 camera.

[b_kosoff]

"LF lenses trade resolution for covering power (Super-high resolution not

being needed for the amount of enlargement LF negs are subject to). In most

cases your MF lenses will be sharper, and the fellow selling the back has

discovered this. "

 

David I'm sorry but the difference in resolution between MF and LF lenses are

minimal, and would still cause the image from a 6x12cm neg to be superior

than that from even a 6x8cm MF camera. I know this from head to head tests.

In fact when I bought my Fuji GX680III I compared the MF fuji lenses, the

180mm, 210mm, 240mm and 300mm wth my Rodenstocks of the same focal

lengths. The Fuji allows you to use LF lenses greater than 150mm on the

camera. The results of the tests? The Rodenstocks were as good, or better

than the Fuji MF lenses when Fuji GX680III was used for both.

 

My statement is not just based solely on that test, but with tremendous

experience with the 15 LF lenses and the 4 different MF systems ( 6x6, x7,x8,

x17) I own (18 lenses). A decent LF lens on a larger neg will almost always

yield superior image quality than a great lens on a smaller format.

 

If Steve's acquaintance is having poor image quality, the odds are that most

likely it is focusing error, technique or even GG alignment and not the lenses.

[david dutchison]

B Kosoff

 

"David I'm sorry but the difference in resolution between MF and LF lenses are minimal"

 

I stand corrected. Nothing to be sorry about, LF lenses have obviously improved since I last used any, which was, um, a long time ago.

[ellis_vener_photography]

I've 6x12cm backs (Horseman and Sinar) on my various 4x5 cameras for quite awhile. I've

had none of the problems the gentleman you refer to ran into. You have to remember that

you are using view camera lenses and technically these will be best in the f/16 to f/22.5

range as a general rule.

 

Calumet makes roll film backs back that I have always been advised to stay away from.

Maybe that was what the gentleman in question was using. I haven't used one so I can't

give you any straight poop on them.

[b_kosoff]

David, no problem.

[ilkka]

How many 'dedicated 6x12 cameras' are there? Horseman uses its own film backs that are also available for use with 4x5 cameras. Film flatness issues should be exactly the same in both cases. Linhof makes a 6x12 camera that should hold the film flatter, but it comes with two lenses and fixed 8 mm rise that may not be suitable for every subject. The cost of that system is also much higher than a complete 4x5 outfit with a 6x12 back.

 

Pros of 6x12 vs 4x5: lower films costs, easier availability, easier to carry and use more frames in the field, easier to take several exposures within a short time, easier to develop.

 

Pros of 6x12 back vs 6x12 camera: Bigger choice of lenses, movements (rise/fall, shift, tilt/swing), ability to shoot 4x5 if required, more exact framing with groundglass.

 

Cons: Slower to use (may be a benefit as it gives more time to think and compose), a little heavier to carry

 

The lenses are typically the same: large format lenses that work best in small apertures. While a Horseman 6x12 can be handheld, it is not really advisable if one is after the best quality. And if not, then why bother to use large format?

 

I think 6x12 makes a lot of sense in a 4x5 camera. Not all images fit to the 4:5 image ratio. When the image wants to be much monger than that, there is practically no quality difference between 4x5 film and 12o film (apart from the possible film flatness issue). To use 6x7 or 6x9 roll film back would be a bit of waste though.

 

Many panoramic photographers prefer to use 4x5 or 5x7 view cameras with 6x12 or 6x17 backs to get all the movements that are not available in dedicated 6x17 or smaller panoramic cameras.

[kelly_flanigan1]

Here I use an old 7x10cm Phase One scan back; on a 4x5 inch camera. There are no film flatness issues. :) But one really can detect a slight focus error; and correct for it; before a long scan. ( with a pre scan) . The back is abit thick; sometimes one can goof and move the camera a microgrunt; while inserting the back. (after a ground glass focus) <BR><BR>In 4x5 rollfilm adapters; there are a mess of tales of great and horrible adapters.