645 print size

Quick question, how big can you print for 645 film without

significant loss in details/qualify?

This is not a question that can be given a quick answer. It depends upon a couple of factors: quality of the original negative; anticipated viewing distance; definition of "significant"; etc.

There's too many factors to give you a hard and fast answer. The factors start with the conception, move through the camera, through processing and/or manipulation through to printing and manner of display. I maight have even left a couple out. What's you ultimate goal?

well, the reason i'm getting into medium format camera is to be able print large, hopefully about poster size. I see people get a nice 12x20 print from 35mm (even from dslr) and wants to know if that 2.7x bigger film would be enough to get me nice print 2.7 times of that 12x20 print.

 

How about the 6x6 or 6x7 then? Does anybody feels limited quickly by 645 that needs that 6x6/7 film? Is it easy to outgrow that 645 film?

The 645 is a much easier camera to hand hold compared to a 6x7. I own both, and when I

am shooting large family groups or corporate work that needs fine detail and large, I'll go for

the 6x7. But for everything else, it's 645 all the way. 16x20 will look really good from 645

or 6x6, but a 16x20 from 6x7 will give you finer grain with more detail since you are almost

doubling the film size.

In my humble opinion, I think that decent 16" prints can be struck off 35mm negs, if you have it all under control. Things such as slow speed film, carefull focusing, higher shutter speed, using a tripod, etc, all add up to better prints.

 

I have made 20 and 30 inch prints off of 645 negs, and feel I could much larger if needed. Remember too that huge prints do not get viewed from 1 foot away.

A helpful rule-of-thumb is: if you're satisfied with a print which is X inches long, made from a piece of film that was Y inches long, and you're wondering how big you could go with a piece of film that is Z inches long, the answer is X*Z/Y.

 

So. You indicated you're satisfied with a 20-inch-long print from 35mm film. A 645 frame is 56mm long whereas a 35mm frame is 36mm long. Thus you will be able to print 645 up to 20*56/36 = 31.1 inches long and maintain comparable image quality when viewed at the same viewing distance. Let's round that to 30 inches long, since this is just a rule-of-thumb calculation.

 

This, of course, assumes comparable shooting techique (proper focusing, tripod, etc), comparable optical quality of the lenses, comparable film stocks, comparable scanner and printer resolutions (assuming digital printing), etc. Given approximate equivalence in all those factors, it really does come down to as simple a calculation as this.

 

Scott

I make a good living from selling fine art color photographs. With my Pentax 6X7 equipment, I rtoutinely print 24" X 30" prints that are tack sharp with essentially no grain, even when using 400 speed film. I generally shoot fine grain 50-100 ASA films. When I exhibit my work, I'm frequently asked if I use large format. I print up to 40" prints that are very sharp, but the grain begins to become noticeable, although not at all objectionable. Sharp prints are VERY dependant on proper technique, of course. A competitor/friend of mine, uses a 645 Pentax and produces beautiful prints, up to 40", although the grain is a bit more noticeable than what I get from my 6X7 prints and his prints are not quite as sharp, although they are very acceptable. Many years ago, when I was faced with the same decision, I went with the bigger film size, since large print quality is my primary objective. However, that was many years ago. Pentax will soon be releasing a 645 digital camera, so if you go with 645 now, you'd already have lenses that would work in AF mode on a 645 digital body up the road. The digital 645 MIGHT produce results with resolution and possibly tonal range that equals that of the 6X7 film format. Of course, the Pentax 67 lenses can also be used on the 645 bodies and the AF confirmation light does light up when they are in focus, but you would not have AF with the 67 lenses on a 645 film or digital body if that matters to you. I does not matter to me any more. I'm personally very happy that I went with the 6X7 format. It works very well for me. The 645 is apparently easier to use than the 6X7, but that was never an issue with me. I've been doing this for a long time and I know how to utilize equipment to its best advantage. The more I use the AF 35mm do-everything equipment for certain things, the more I enjoy the challenge of using my manual focus, match needle big Pentaxe 67s. It's the end results I'm after and to me, the Pentax 67 equipment is a breeze to operate, compared to 4X5 or any of the larger formats that many of my counterparts use. All things considered, I get results from 6X7 that are almost as good as with 4X5.

 

www.georgerhodes.com

The largest print I've made from my Bronica 6X4.5 was 4X5 feet. Looks great from the viewing area (approx 7-8 feet away). Cut that distance in half and it looks very soft.16X20's look great at less than arms length.

A fundamental part of the answer is the viewing distance. One school of thought says that the viewer steps back to survey the entire image, so that they view it from about the same distance away as the diagonal length of the print itself. If you buy into this then your problems are pretty much over, provided you're shooting with 35mm film or a larger format.

 

It's an aside but the reason I say 35mm, and not say APS or Minox film, is that 35mm is usually regarded as the minimum size film format required for a completely sharp and grain free 10" x 8" print. And this size print has a diagonal length that conforms with the minimum comfortable viewing distance of ten to twelve inches, go closer than this and your eyes become increasingly uncomfortable and strained.

 

However, IMO this theory of steadily increasing viewing distances is fatally flawed for two reasons.

 

Firstly, the vast majority of prints are viewed hand-held, and our arms don't automatically stretch to accomodate bigger prints. Given that many of us are now using inkjets and printing larger than we've ever done before we're now tending to view bigger and bigger prints from closer distances. Secondly, IMO there's something in the very nature of a photograph that invites close scrutiny. See a detail rich print and you instinctively step closer to examine it.

 

So I'd argue that you really do need to consider film formats when you're thinking about how big you can print.

 

Another way of addressing the question is to think about the impact of enlargement on key photographic variables like handheld camera shake, depth of field, and diffraction. You can dismiss the first one, camera shake, with a tripod and a cable release. But if you are handholding then you'll see quality losses very, very quickly.

 

The next two, diffraction and depth of field, are critical limits if you want to retain front to back sharpness with a three dimesnional subject. The hard facts are that the depth of field guidelines engraved on a 645 lens will probably assume a "circle of confusion", (the blurred diameter on the negative of a sharp point in the subject), that's about 50 microns in diameter. So if you're relying on hyperfocal focusing to deliver a critically sharp print you'll struggle to achieve anything larger than 10" x 8" from 645, in fact if you're ultra picky you'll start to see the first effects of lack of focus even in a 5" x 7" print.

 

But stopping down to give yourself a generous depth of field safety margin is unlikely to work in practise either, because now you'll be caught out by diffraction. At f8, with a theoretically perfect lens, an infintesimal point in the subject is recorded as a 9 micron blur in the negative due to diffraction. Stop down to f16 and that blur becomes 18 microns wide, and at f32 it doubles again to 32 microns. So in the attempt to make the out of focus areas sharper, diffraction means we make the entire image that bit softer.

 

The message is that achieving large prints that retain critical sharpness throughout the image is incredibly difficult to achieve.

 

Sure, step back a bit from the print, concede that sharpness is only required in part of the subject, and find a subject that's not too deep front to back or doesn't contain extremely fine detail. Then yes, you can get 11" x 14" or A3 prints pretty regularly from a 645 negative.

 

But raise the standard a little and 16" x 20" becomes very tough, and 20" x 30" is really the preserve of large format with camera movements to gain depth of field at more modest apertures.

As a quick answer, a fine-grained film scanned at ~4000dpi and then resized for printing

at 300dpi gives me prints at about 24x32".

 

Stipulating an increased viewing distance, I can't imagine that it would look objectionably

worse at 200dpi, which would give a print size of 36x48". How much bigger, really, do

you need?

 

At 24x32", 645 will be visibly better than 35mm film or an 8mp 20d image. Larger film

sizes will be better yet. At a workshop with Charles Cramer, we compared 16x20" prints

of the same subject taken with 35mm, 645, 6x7, 4x5, and 8x10. Close inspection showed

an increase in quality at each step, most notably from 35mm to 645 and from 6x7 to 4x5.

What is "enough" for your purposes?

"At a workshop with Charles Cramer, we compared 16x20" prints of the same

subject taken with 35mm, 645, 6x7, 4x5, and 8x10."

 

I did a similar exercise nearly thirty years when I was a photographic student.

We made10"x8", 11"x14", 16" x20", and 20" x 30" prints from 35mm, 645

(cropped 6x6), 6x9, and 4"x5".

 

We viewed the prints in "reverse order", starting with 20x30 prints from a

35mm negative. Looking at this print in isolation the general consensus was

that it was just acceptable. But as each version from a larger negative was

produced so it became plain that the quality gains kept on coming, right down

to a 10x8 print from a 4x5 camera. I kept those prints and they've guided my

photographic choices ever since.

 

I think about them whenever I read photographers enthusing about 30x40

prints from an APS-C sized digital sensor. Yes, you can make a powerful and

compelling shot that may fully meet your requirements, but it doesn't mean the

same shot from a larger format camera wouldn't be even more powerful and

even more compelling.

Hi Steve. I shoot 645, having shot 35mm for years. I typically drum scan my best chromes and make prints with Photoshop and a Chromira printer.

 

Assuming the image is sharp, the content will dictate the size. For 35mm, an eagle might go to 16x20 with ease, while a wildflower meadow might fall apart beyond 8x10. In detailed landscape shots, 645 allows me to go one or two paper sizes larger than 35mm.

 

I'd recommend borrowing a 645 before buying. I've found that my 35mm primes are noticeably sharper than my 645 primes. What's more, for my style of shooting, 645 is punishing in the depth-of-field department. For instance, with a 45mm lens in 645 (about a 28mm in 35mm), I get about five feet to infinity in sharp focus at f22. In 645, I often have to let my backgrounds go a bit soft to achieve crisp foregrounds. Sometimes this looks great. Other times it doesn't. To achieve sharpness throughout, I've had to change the way I compose. Because depth of field is so critical on many landscape shots, I can understand why many photographers shoot 35mm and large format exclusively.

 

Ian

Hi Steve, I have used 35mm and 645 film cameras for weddings and portraits for 30 years and digital Nikon D2X for about 14 months. It seems that everyone wants 8 x10s but also wants to see the pictures the same day. My digital is 12 mp so when it is blown up to 8 x10 the quality isn't what they are wanting. a scan of my 35 mm with my 4800 x 9600 scanner gives me 68 mb to work with. Using these files I can crop easily and still have excellent 8 x 10's. The 645 scanned gives me 184 mb and 11 x 14's are also evcellent after cropping. Depending on my shots 35mm is good for 8 x 10's all day long and the occasional 11 x 14. The 645 goes to 16 x 20's and even the occasional 20 x 30 without much problem. What I have ended up doing is hiring college students to use the digital by my side and I call out the mm settings to them. On the rare occasion that I need to shoot all 35mm and expect to see many 8 x 10 and 11 x 14's I shoot my Nikon F3 using my Mamiya lenses which are far superior lenses and the outcome is excellent. Everything depends on the negative quality and for the most part the better the lens (and Photographer)the larger you can go.