Equivalent length for medium format 6X7 90mm to full frame Nikon

[Alan Edward Klein]

Totally - I need to scout locations for tableau photos with my RB67, but as it is cumbersome and I already have my DSLR with me wherever I go, I was hoping to use the DSLR to see how different locations would work on the only two Mamiya lenses I have, i.e. can I use this location for a specific shot I had in mind, or will e.g. a third of the scene be cropped out.

Which is why I was so happy to find out about "Viewfinder Preview", which I think will change things up massively for me.

What I did is compare at home the zoom position showing the same horizontal view (width) on my digital micro 4/3 camera to match the view on the various lenses for my RB67 and 4x5 film cameras. Then I noted the positions on the digital zoom lens.

Then, in the field, I could use the digital camera as a viewfinder to find the matching lens to use on the two film cameras.

 

[Ian Grant]

Often the quality of the question is the foundation for the quality of the answer.

Ralph is right, it is a simple question and only needs a simple answer, a very rough approximation is all that is needed.

Ian

 

[DREW WILEY]

Compositional and depth of field strategy is always going to be somewhat different scaling up to MF, regardless. 35mm is only an approximate scouting too at best, yet one which I myself sometimes use, mostly just for a change in mental scenery once in awhile, but which does help me spot certain subjects I subsequently return to with heavier artillery.

 

[wiltw]

Choosing the right lens for a different camera to photograph a block print according to the same perspective, well, that might be important to someone. It would be to me if the copy stand were involved. Or it might be important to someone photographing a cramped interior space. Or maybe they just want reasonably matched lenses due to familiarity of visualization related to angle of view, or just for the hell of it. It's a legitimate question.

^
I can state from direct experience...I shoot in four different formats. I have done 'focal length equivalence' calculations only when newly working in a format, to assist in selection of lenses to have for that format...and once chosen and put into the bag, I never engage in any mental arithmetic calculations for ANY purposes at all, I simply grab and shoot..with no 'equivalent FL', no DOF, no Hyperfocal calculation computations in the field

When shooting only Medium Format, and shifting between 6x6 and 6x7 and 645, there is no mental computation...you simply 'pick up the Normal', or 'pick up moderate wide vs super wide' which is appropriate to that format. 135 vs. medium format is no different than chosing between different medium format bodies. After all, when one calculated the true equivalent FL, that FL may simply not be available for that camera because zooms are not always available!

 

[DREW WILEY]

Things really change when upscaling to LF, or even the use of MF backs on view cameras, since you gain is a whole additional suite of controls, handling depth of field and perspective issues.

 

[wiltw]

Things really change when upscaling to LF, or even the use of MF backs on view cameras, since you gain is a whole additional suite of controls, handling depth of field and perspective issues.

I shoot 4x5 as one of my four formats...there are only three lenses that I have for it...'normal', 'very wide', and 'ultrawide wide'...I have never bothered to figure out that the 75mm FL on 4x5 is 'equivalent to N for 135'.
Yes, large format allows you to do things not achievable with 135, or even with most medium format. But FL is not one of them!

 

[DREW WILEY]

Long focal lengths are much easier, weight and bulk wise, just extending a 4x5 bellows than with conventional MF gear. For example, the 300 EDIF for my P67 SLR is the size of a howitzer barrel, and I need the same big wooden Ries tripod as I use for my 8X10 camera to ideally support it steady. On the other hand, using a 6X9 roll film back on even my little Ebony 4x5 folder, along with a petite 300 Nikkor M view camera lens, and the much lighter weight tripod capable of handling that well, I've got just a fraction of the cumulative weight and bulk to deal with, PLUS full view camera movement options to better control depth of field etc. ....

BUT when it comes to rapid operation in the wind and rain, or wildlife shots, etc, the big Pentax tele route is far more convenient; and I even have an excellent Nikon adapter for it if needed. It's a superb fast optic. But I only carry it for day hikes or roadside shooting, never on multi-day treks.

 

[redbandit]

That would only work if the DIGITAL CAMERA FULL FORMAT SENSOR was the same SIZE as your 35mm film negative. They arent last i checked.

I believe on digital cameras the sensor is a shade smaller..

However why worry about trivial things like equivalent lens length? Each format has its own preference, and i always thought ive read 60 or 80 is the "equivalent"

 

[koraks]

That would only work if the DIGITAL CAMERA FULL FORMAT SENSOR was the same SIZE as your 35mm film negative.

Which is indeed the case, so that's convenient. Turns out it's called "full frame" for a reason.

 

[Alan Edward Klein]

I shoot 4x5 as one of my four formats...there are only three lenses that I have for it...'normal', 'very wide', and 'ultrawide wide'...I have never bothered to figure out that the 75mm FL on 4x5 is 'equivalent to N for 135'.
Yes, large format allows you to do things not achievable with 135, or even with most medium format. But FL is not one of them!

It's a natural question that most photographers new to a different format would ask. How else would they know what lenses to buy? Of course, once they bought the system and lenses, then comparisons would rarely be needed.

For those wishing to buy or fabricate a director's viewfinder of some kind, then these questions become viable again. Let's say you decided to shoot portraits. Your normal lens is too wide. So if you;r familiar with 35mm, you'd know that 85mm-135mm makes good portraits lengths depending on how much of the portrait you want. So that would help in your selection.

By the way, the link to the chart I provided earlier, has different portrait selections for figuring out distances to subjects for each format and lens and the reverse.
DOF, lenses angles, calculator

 

[peterB1966]

Often the quality of the question is the foundation for the quality of the answer.

Not necessary.

 

[wiltw]

That would only work if the DIGITAL CAMERA FULL FORMAT SENSOR was the same SIZE as your 35mm film negative. They arent last i checked.

I believe on digital cameras the sensor is a shade smaller..

However why worry about trivial things like equivalent lens length? Each format has its own preference, and i always thought ive read 60 or 80 is the "equivalent"

'Full frame' for 135 format is indeed 24mm x 36mm in both film and digital sensors.

'Full frame' for medium format is less than 56mm x 56mm (6x6), or even 56mm x 43mm (645)..
e.g. Hasselblad XD2 100C: 43.8mm × 32.9mm
e.g H6D-100c : 53.4mm × 40.0 mm