6x8 vs 6x7

[steve_horn]

I am thinking about moving from 35mm to MF - mostly for landscape

photography. In another thread I have been trying to find out

information about the 6x8 power film holder for the Mamiya RB67.

 

I am wondering how much quality difference can be expected between

6x8 and 6x7. I did some sums:

 

6x8 is 56 x 75 = 4200 sq mm (with the longest edge horizontal the

width is 75mm on the Mamiya)

6x7 is 51.86 x 69.5 = 3604 sq mm (cropped for the 4:3 aspect ratio

which I like)

 

So 6x8 has 16.5% more area than 6x7. If I want the extra negative

area, I will limit myself to getting an RB67 Pro SD, and one or more

6x8 power film holders (£300 second hand - ouch!). If I can be happy

with 6x7 I will have more options.

 

Is 16.5% worth it? I would be grateful for any opinions.

 

Thanks in advance.

[terry_dvorak]

I think I asked Mamiya about this option a couple of years ago; I wondered why more RB/RZ shooters didn't avail themselves of this larger-negative option. If I recall correctly, Mamiya kind of discouraged me from trying it, primarily because (I think) in the Mamiya viewfinder you can only see the 6x7 portion of the 6x8 image. If true, that would be a major detriment offsetting (to me, anyway) any minimal gain in film area.

 

I decided that if I wanted 6x8, I'd shoot the GX680, and if I wanted to use the RB67, I'd stick with 6x7.

[djphoto]

I use the Fuji 680GX, but see no advantage whatever to the extra centimeter because it has to be cropped off to fit standard paper sizes. If I could afford it, I would get the 680III body and use the 6x7 mask most of the time.

[steve_horn]

I should have said that I will mostly be viewing results on my 1600 x 1200 computer screen. The 4x3 ratio fits the screen and I think it is a pleasing shape for landscapes.

 

I will get some pictures printed but these will be in the minority, so cropping to paper sizes is not a big issue.

 

The big question is whether the extra negative area is worth having, taking into account the limitations it will impose.

 

Since I started viewing pictures on-screen I have become a resolution junkie. I scan the negatives to a big file and when viewing I like to zoom in to see detail. But with 35mm, although I can see some more detail it does not look attractive. To much grain.

[joseph_albert]

The area difference is irrelevant to the discussion. What is

relevant is the aspect ratio of your final images and whether or

not you plan to crop. Many small format users make the mistake of

trying to apply everything they know about 35mm photography to

medium format. In fact, once you have a larger negative, you have

the freedom to crop while still maintaining a quality image, whereas

in small format the mentality is usually to fine tune the composition

in the viewfinder so that the slide or negative might be printed

full frame. Of course, even 35mm is cropped to produce 4:5 prints.

<p>

The 6x8 format will only provide slightly better image quality in

situations where you would be cropping 6x7 in a manner that reduces

the vertical dimension (ie cropping along the long side to reduce the

length of the short side). If you don't plan to crop like this,

there is no quality advantage to 6x8.

<p>

For me, the biggest and only important advantage of 6x7 over 6x8

would be that I could plan to do 4:5 aspect ratio images full frame

and still have some cropping freedom with the 6x8 images. Don't

underestimate the advantage of fine-tuning the composition after

the fact when you have plenty of time to look at the image in the

comfort of your work space.

<p>

The biggest disadvantage of 6x8 is that it won't fit in a 6x7 enlarger.

I think Beseler makes a 6x9 enlarger, but they aren't very common.

Thus, you'll probably be using a 4x5 enlarger for 6x8. This will

increase the fixed cost of equipment if you own your own darkroom,

or increase the variable cost of having a lab do the work since

some labs charge more for prints from materials that are too large

for a 6x7 enlarger, and some labs don't do them at all.

[joseph_albert]

PS You don't need medium format if the goal is to view on a 1600x1200

computer screen. 35mm has more quality than you need for this, so

why give up the convenience? For that matter, an inexpensive

digital camera will work fine.

[jeff_drew4]

<< I am wondering how much quality difference can be expected between 6x8 and 6x7. >> Dittos to what Joe said! Framing the shot and printing it are important for the end result. 6x7's print on 8x10 papers with very little loss of content. Some people like 6x9 vs 6x7; are you rationalizing a compromise or do you have a specific need that would dictate 6x8? << Is 16.5% worth it? >> For me and my uses, it would not be worth it, and I'll 'fess up to never considering 6x8 . . .having scaled down from 4x5" & 6x9cm to 6x7cm.

[patrick_drennon]

I shoot a GX680III. The only advantage I've found to the format

size is when shooting in studio on standard width seamless, I

have no problem with hitting the edges on full length shots. For

me it seems to affect alot of what I shoot (I also have a P67

system). I've accidently turned into somewhat of a camera

collector and they all seem to be wonderful at certain things.

None do everything perfectly.

 

One other strange note, I use an Olympus A3 size dye sub

printer. The true max area is actually 10.2 in. X 7.6 in. That just

happens to be the exact aspect ratio of 6X8. I found that out by

accident but have used the discovery to advantage several times.

[djphoto]

" I think Beseler makes a 6x9 enlarger, but they aren't very common."

 

 

The Beseler 23C, which I use, handles up to 6x9 and is as common as dirt.

[marek_zaluski]

Steve, I did not use Mamiya, but Pentax 67 format is 56 mm x 69 mm. This makes 3864 sq mm.

[steve_horn]

Joseph Albert says:

 

>PS You don't need medium format if the goal is to view on a1600x1200 computer screen. 35mm has more quality than you need for this, so why give up the convenience? For that matter,an inexpensive digital camera will work fine.<

 

I am not sure that you are right that with a 1600x1200 pixel file you cannot tell 35mm from MF. In my opinion, digital pictures that come from MF have a sort of 'effortless sharpness' that 35mm lacks.

 

But, as I said, as well as looking at the whole picture, I like to look at detail. so I make one 1600x1200 pixel file and I also make another one at a much higher resolution.

[joseph_albert]

Steve,

<p>

It takes roughly 3000x4500 pixels to render the detail captured

in a fine-grained, high resolution piece of 35mm film. 1600x1200

is around 1.9 megapixels. I would think a 2.1 MP or 3.3 MP digital

camera would be the ideal tool if your goal is viewing images on a 1600x1200

monitor.

[roberto_manderioli]

Steve,

I shoot 35mm, 6x7 (Pentax) , 6x9 (4x5 camera with 6x9 RFH) and 4x5 .

To me the difference between 6x7 and 6x8 is not relevant as there are far more aspects that play an important role for the final quality of the print.

For landscape the best is a view camera because of the movement. If you want to use MF then 6x7 will produce very fine results anyway , 16.5% is a margin that absolutely gets lost among the many other factors involved.

 

(BTW a new 6x9 roll film holder for a 4x5 costs less than the second hand back you mentioned)

 

Just my 2 cents

 

Good luck,ciao

[dave_bazzel1]

As I rationalized the same questions when I decided to go to MF for my landscape work I felt that recent advances in film technology, specifically ProviaF changed my decision from a Pentax 67II to a Pentax 645N. I know this isn't exactly what you asked but I thought I'd share the math in case it is relavent to anyone also thinking about a move from 35mm to MF. Follow this math (all approximations)....ProviaF RMS 8, many other 100 ISO films are 10 to 11 RMS. This is an increase of, let's say 25%. 6x4.5 increased size by 25% is approx a 6x7. Sooo, I decided to take the extra depth of field, lighter weight, ease of use, etc. and go for the Pentax 645N and use ProviaF. I also agree whole heartedly that it's all about composition ultimately. Purely food for thought.

[steved1]

>I use the Fuji 680GX, but see no advantage whatever to the

>extra centimeter because it has to be cropped off to fit

>standard paper sizes.

 

I see this argument all the time and usually ignore it but this time I can't help myself.

 

What do you mean "has to be cropped off"? Says who?

I guess there is no point with the extra 10 centimeters in a 6x17 panorama either then, huh? Because you "have to" cut off most of it to make it fit a standard paper size.

 

Seriously people... who in his right mind makes his or her artistic cropping decisions based on the PAPER SIZE that the print paper manufacturers have settled on?

 

Papers (in case you didn't know) can be cut to whatever size you want. This "won't fit the paper" thing is a silly, silly argument.

 

Just do your full frame (or cropped) prints in any aspect ratio you want. Yes, if you do a full frame print of a 35mm shot you get some "unused" paper above and/or below the actual print, so? Cut it off and be merry.

 

Steve