Most current MF cameras/digital backs have a 44x33mm (Hasselblad H6D 50C, Leica SL, Pentax 645, Hasselblad X1D, Phase One 50MP Mamyia Leaf Credo 50) or 43.8x32.9mm (Fuji GFX 50S, Mamiya Leaf Credo 40mp) sensor.
The current 100mp Hasselblad and 100mp and 80mp and 60mp achromatic Phase One digital back sensors have a 53.7x40.3 or 40.2mm sensor.
The reason for the smaller sizes is manufacturer (Sony for instance) based, and cost based. The bigger sensors are very expensive in comparison.
That is also a reason why MF digital sensors have always come without a AA-filter, AA-filters are very expensive to produce and the small quantities and large sizes prevented MF cameras to have them.
And the reason for most, if not all, sizes from film era, are more or less coincidentally. There were hardly artists saying "Oh, for my next landscape project I feel like I need 72 × 56 negative format, please make me one". It was more defined by the machines producing and cutting the films. As the 135 films always lost more than 30% of possible area due to perforation, that relation was way better with 120 rolls or LF single sheets.
However, in film era there were few cameras which could produce various sizes by opening or closing the space like in a movie theatre opening the curtain - in digital era, various sizes are always at loss.
01-27-2017, 10:02 AM
(This post was last modified: 01-27-2017, 10:02 AM by obican.)
Best example of what you've said is probably the XPan, which shoots either 36x24mm images or 65x24mm panoramic ones onto 35mm film. 65x24mm is about the same you'd get by cropping to top and bottom of 6x7 behemoths and the image circle easily rivals modern 6x45 systems.
120 film is great. It is still relatively inexpensive, is essentially the same thing as 35mm cut larger (so you can think of medium format sensors having same pixel density as 35mm or APS-C) so the lower magnification while enlarging is helpful in minimizing grain size while maximizing pretty much everything else. And you can use it on a lot of different cameras, ranging from 10$ plastic boxes made by Soviets to 5000$ Hasselblad systems, 6x45 modern cameras with autofocus to 6x17 cameras with no automation at all.
The reason why I always get a bit snappy about this "medium format" marketing blurb - which is for some of the backs BC mentioned no blurb, because these are very close to 56×42 mm (4/3 proportion) and have a diagonal of 70 mm, while "FF" (3/2 proportion) has 43.3 mm diagonal, leading to 1.6× crop factor. Okay, the proportions are more interesting than the crop.
Getting a squarish frame out of FF will cost me 1/3 of the sensor area, leading to 34 mm diagonal. From a "real" MF with 4/3 proportion I also loose 1/3 of the sensor area, but get a diagonal of 59.4 mm, Crop increases to 1.75×.
Or you can use a "real" real MF and enjoy the 80mmish diagonal on glorious 120 format 6x6 film 
How does the Xpan get such a broad image? They only use 30mm, 45mm and 90mm lenses. I could not find the info about the construction of the camera.
Has it to do with the distance between lens and film plane? The lenses seem the same as normal lenses, a Nikon 30mm also was used.
I wish there was a true digital panorama camera. I know there are ways to produce a panoramic image, but the problem is you cannot see the whole image until you have stitched it together on your computer. With the analog panoramic cameras, you could see the whole image through the viewfinder. That was a lot easier to compose an images.
Too bad there is no curved panoramic back for my Noblex  .
Kind regards,
Reinier
Quote:How does the Xpan get such a broad image? They only use 30mm, 45mm and 90mm lenses. I could not find the info about the construction of the camera.
Has it to do with the distance between lens and film plane? The lenses seem the same as normal lenses, a Nikon 30mm also was used.
I wish there was a true digital panorama camera. I know there are ways to produce a panoramic image, but the problem is you cannot see the whole image until you have stitched it together on your computer. With the analog panoramic cameras, you could see the whole image through the viewfinder. That was a lot easier to compose an images.
Too bad there is no curved panoramic back for my Noblex .
Kind regards,
Reinier
If the XPAN makes twice as wide negatives in panorama mode compared to normal 35mm size, the 30mm lens will give about as wide a view as 15mm on 35mm format, the 45mm lens like a 22mm lens, and the 90mm lens like a 45mm lens on 35mm.
The lenses obviously need to provide a big enough image circle.
You can easily make panorama photos as wide as you can with the XPAN, use a 15mm lens on FF.. With FF you can even go to 11mm nowadays...
Quote:How does the Xpan get such a broad image? They only use 30mm, 45mm and 90mm lenses. I could not find the info about the construction of the camera.
Has it to do with the distance between lens and film plane? The lenses seem the same as normal lenses, a Nikon 30mm also was used.
I wish there was a true digital panorama camera. I know there are ways to produce a panoramic image, but the problem is you cannot see the whole image until you have stitched it together on your computer. With the analog panoramic cameras, you could see the whole image through the viewfinder. That was a lot easier to compose an images.
Too bad there is no curved panoramic back for my Noblex .
Kind regards,
Reinier
Xpan lenses are actually designed to cover 6x45 image circle so you can actually call them medium format rangefinder lenses. It has a massive film gate.
![[Image: Hasselblad+XPAN+Panoramic+film+camera+(1...NS+KIT.jpg]](https://www.creative-camera.com/images/70521/attachment-full/Hasselblad+XPAN+Panoramic+film+camera+(14010)+With+45MM+F+4.0+LENS+KIT.jpg)
I get it now. It is jusr a cropped MF camera.
The Mamya 7 had a panoramic adapter. It adapted 6x7 inch film into a 35mm panorama. Which work well.
A wide angle lens could work, but still there is a lot distortion. I know you can do something about it in LR or so. But the IQ decreases because of it.
And sadly I do not have a FF anymore.......
A tilt shift lens can also be used for panoramas, but then again you do not see the entire image in the field.
Kind regards,
Reinier
01-29-2017, 08:24 AM
(This post was last modified: 01-29-2017, 08:25 AM by Brightcolours.)
Quote:I get it now. It is jusr a cropped MF camera.
The Mamya 7 had a panoramic adapter. It adapted 6x7 inch film into a 35mm panorama. Which work well.
A wide angle lens could work, but still there is a lot distortion. I know you can do something about it in LR or so. But the IQ decreases because of it.
And sadly I do not have a FF anymore.......
A tilt shift lens can also be used for panoramas, but then again you do not see the entire image in the field.
Kind regards,
Reinier
You get the same distortion with 30mm on 2x 35mm film width as with 15mm on FF...
Just like you get the same distortion with 7mm on MFT.
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