Lens set based on field of view (FOV)?

[pete22230]

Hi everyone;
I'm a newbie to LF and thinking about lens sets. I currently have 2 lenses: a rodenstock 80mm f5.6 Grandagon (not a Grandagon-N) and a schneider symmar-s 180mm f5.6. I find I am looking at scenes from an "I want more/less field of view" (FOV) point of view rather than a "more/less focal length" (FL) point of view. I understand that there is a gross relationship between FOV and FL but depending on lens manufacturer/design it can be somewhat nebulous. Since I don't have full specs on the Grandagon I'm unsure of it's actual FOV but I would think it's 100+ degrees vs about 70 degrees for the Symmar-S. So on occasion I have found myself wishing for something between the 2. I also figure at some point I'll be getting a longer lens like a Nikkor M 300mm or maybe even a Nikkor T-ED 360mm. So what would you folks recommend for an in-between lens between my existing and that would have A) hopefully about an 85 degree FOV B) a modest lens hood diameter so filters are easy C) a bright lens say f5.6 D) a maximum image circle and E) light weight F) sharpness. Not asking for much am I!!!! Reading up on this I came across reference to a 120mm Schneider Super-Symmar HM that looked interesting but I'm sure there must be other choices. Any thoughts you might have would sure be appreciated.
Many thanks
Pete

[Dan Fromm]

Oh, dear. You're confusing the angle the film sees with the angle the lens covers. If the lens covers it, the angle the film sees is given by focal length.

On 4x5, an 80 mm lens (assuming it covers the format) will give a 61 degree vertical angle of view and a 74 degree horizontal angle of view. The diagonal angle of view will be 86 degrees. For a 180 mm lens, 30, 37 and 45.

Learn to do the calculations. Angle of view covered given focal length is, in pidgin Excel, 2*atan(degrees((circle/2)/focal length)). For 4x5 and vertical AOV, the circle is ~ 95 mm. Horizontal, 120 mm. Diagonal, 150 mm.

About lenses. Learn to use this site's resources. In particular, see http://www.largeformatphotography.in...mainly)-lenses

[Bob Salomon]

80mm?

The most common 3 lens set for 45 is the 90, 150, 210mm.

[Corran]

I'm sure you meant a 90mm Grandagon. There's no reason to consider lenses based on the FoV. For your 90 and 180, the obvious in-between is a 135mm, and the next step up probably a 300mm. Whether or not those work for you depends on your individual needs and seeing. Lately, my preference has been 90-150-240 (also 58).

More importantly as a self-proclaimed newbie is to go out and make photographs to determine what you need in terms of lenses.

[Pere Casals]

FOV

Hello Pete,

Here AOV is described: https://en.wikipedia.org/wiki/Angle_of_view

Here you have a calculator, you can also donload an App for your phone: https://www.scantips.com/lights/fieldofview.html

Angle of coverage: the circle of image of an LF les is usually large than the film, "allowing movements".

Here you have image circles and angle of coverage of some lenses: http://www.largeformatphotography.in...s/LF4x5in.html

Please note that when you focus a near subject with an LF camera you give bellows extension, the image grows a bit, and the Angle of View decreases a bit from what it was for a distant subject.

Regards

[Oren Grad]

I'm sure you meant a 90mm Grandagon.

FWIW, there was an 80mm Grandagon, early on. AFAIK it didn't survive into the Grandagon-N generation and it's not nearly so common as the various 90mm Grandagons, but there are some floating around out there. So the OP will have to confirm for us whether that was just a typo or whether he really does have the 80.

[Corran]

Huh, never heard of that, my bad. Perhaps it is that then.

[Bob Salomon]

FWIW, there was an 80mm Grandagon, early on. AFAIK it didn't survive into the Grandagon-N generation and it's not nearly so common as the various 90mm Grandagons, but there are some floating around out there. So the OP will have to confirm for us whether that was just a typo or whether he really does have the 80.

And, if he does, has he tried it to see how much it covers? That was a pretty old lens and was long discontinued when we became the Rodenstock distributor in the 80s.

[Doremus Scudder]

As Dan points out, you shouldn't confuse the angle of coverage (i.e., how big an image circle the lens projects) with the angle of view. This latter is directly related to focal length, so you really don't have to worry about it; just think in terms of focal length. This is somewhat easier for me than working out angles for all three parameters (width, height and diagonal).

Angle of coverage is important for choosing a lens with the coverage you need for whatever movements you commonly use (or to see if it covers a specific format at all), but it does not relate to the angle of view; rather different lens designs in the same focal length can have very different angles of coverage.

As for choosing lens sets. Many (me included) like a set that progresses in approx. 50%-focal-length intervals. Example: 90mm - (50% of 90 is 45; 90+45=) 135mm - (50% of 135 is 67.5; 135+67.5= 202.5) so a lens in the 200-210mm range is good here (my Ektar 203mm is very close ). The next entry in the series would be 300mm. This is what I carry most of the time in the field for general work.

But, you've got an 80mm and a 180mm already. So if you wanted to "split the difference" with the lenses you have already (assuming you do have the 80mm Grandagon, not the 90mm), then your 50% sequence would be: 80mm - 120mm - 180mm (- 270mm), etc. There are several good 125mm lenses (the Fujinons leap to mind) that would fit the bill quite well. Most ~120mm lenses are "wide-angle-of-coverage" designs (e.g., Super Angulon, Grandagon, SW). These are bigger, but have lots of coverage for 4x5. The type of work you want to do and the needed coverage will dictate which direction you want to go here. The 125mm-135mm Plasmat-designed lenses have less coverage, but are much smaller and lighter.

FWIW, I augment my 50%-increment set often depending on what I'm shooting. When working in cities, I add a 180mm and a 240mm and leave out the 300mm (entire kit: 90mm, 135mm, 180mm, 210mm, 240mm). I find this gives me more framing possibilities in places where choices for camera placement are limited. When working canyons in the SW, I'll add a 75mm and leave out the 300mm and go wider on the long end (entire kit: 75mm, 90mm, 135mm, 180mm). And even for general use, when I have room, I'll toss in a lens to fill in a gap that I think might need filling (often it's the 240mm Fujinon A that gets added, since it's so small). It's all highly personal and subject-specific.

For you, the obvious choice is something in the 120-135mm range. The decision should be based on the coverage you need vs. size/weight. Personally, I really like the 135mm focal length, but I like a lot of coverage. My choice here is the 135mm Wide-Field Ektar for the coverage. Your choice may be different. However, as far as quality goes, any of the lenses from the reputable manufacturers will be fine.

Hope this helps,

Doremus

[Dan Fromm]

Doremus, a set of lenses with 50% steps between focal lengths is interesting. Useful, too. But it isn't the only one.

I bought my first real camera, a Nikkormat FTn, in 1970. It came with a little pamphlet on the basics of photography. I learned a lot from the pamphlet and the exercises in it, still have it. Anyway, in it Nikon recommended a lens set with 100% steps. Double focal length upwards, halve it downwards. I took their advice, ended up with a kit that that had 24 mm, 55 mm, 105 mm and 200 mm lenses. I later added a 400 and (heresy!) a 35. My first longer lens was a disaster of a 1000, quickly sold off. Eventually I got a 700. When my kit was stolen I replaced the 35 with a 35-70 zoom. And there, more or less, is my 35 mm kit.

When I moved up in format to 2x3 I started with a normal lens, 101 mm, later added too many other lenses and ended up with more kit than I can carry and with focal lengths in relatively small steps. Too many choices. I've since slimmed down what I try to travel with to steps of around 50%. I see this as tidy but entirely arbitrary.

OP, my point here is there really aren't any hard and firm rules. Like it or not, you'll have to find your own way.