Tilt will increase DOF by how much?greenspun.com : LUSENET : Large format photography : One Thread
For several years now I've been frustrated by not obtaining adequate sharp focus in "near-far" type landscape shots. I'm currently using a Pentax 67 with a 45mm lens for most of these type shots, and am wondering if a move to 4x5 with movements will increase the DOF. Which movements will help the most, and which camera should a beginner consider, with low cost ( under $1000 for body and WA lens )used? Any and all suggestions appreciated.
-- Michael Mahoney (firstname.lastname@example.org), February 21, 2001
You might take a look at the older Calumet 400 series cameras. They are a well built monorail with all movements except rear rise. The weight is aprox. 5lbs. You can almost always find them on e-bay, price generally varies acccording to condition. Two years ago I paid 175.00 for mine, including a case. The first lens I was willing to take outside is a Zies Jena Tessar 135mm f4.5 $55.0, again on e-bay. This uncoated OLD lens is signifigantly sharper than I anticipated, even when compared side by side with a Rodenstock 135mm sironar-s. This was an inexpensive investment to see if I wanted to shoot outside. I still use this camera even though I have others. Hope this helps.
-- Richard Hill (email@example.com), February 21, 2001.
Michael: With the front and back tilts on a view camera and a lens stopped down a bit, you can realize almost unlimited depth of field. It is possible to obtain focus from a few inches to infinity under many conditions. I often make near-far photographs with an object just in front of the lens and maintain sharpness through infinity. That is primarily with a foreground object such as flowers or foliage at the bottom of the image and the distant object at the top. There are several low cost wooden field cameras which fit in the price range you mentioned. In addition, there are many, many good used ones on the market. I would suggest you do not but the press type for your stated purpose, although a technical camera such as the Linhof, MPP, HOrseman and others work fine. You need back tilt, and the pure press cameras do not have it.
Good luck with your quest,
-- Doug Paramore (firstname.lastname@example.org), February 21, 2001.
A move to 5x4 won't increase depth-of-field, but it will allow you to control the plane of sharp focus.
For example, with a 75mm lens (about the equivalent of your 45mm), the difference between infinty focus and 1 metre is 6 mm of bellows extension. Tilting the lens by just under 3 degrees will result in the focal plane being shifted by 6 mm over the long dimension of the 5x4 format. This means that one edge of the film can be focussed at 1 metre, and the other at infinity; and 3 degrees is by no means a large amount of tilt.
These shifts and tilts can be applied in both axes, so that almost any two points on the film can be brought to a sharp focus at the same time. Note the word 'points'. Camera movements can't bring large areas of the scene to a sharp focus simultaneously.
If your 45mm is your favourite lens on 6x7, then you should go for something like a 75mm Super-Angulon, Nikkor SW, or Grandagon, allowing about $500 to $600 for a good used example (dealer prices), and the rest for a monorail type camera with bag bellows. IMHO a view type camera would be more suitable for general outdoor use, but they're not very practical with short focal-length lenses.
PS Look for a deal on the camera that includes a few double dark slides - they can be surprisingly expensive.
-- Pete Andrews (email@example.com), February 21, 2001.
Michael: I did exactly what you are wondering about a little more than two years ago now: I abandonned my Pentax 67 in favor of 4x5 view camera. Believe me: I'll never go back to MF SLR (altough I still find useful my 35mm SLR). My first purchase was a TOYO 45 AII and Nikkor 90mm but you can certainly find a cheaper and perfectly efficient outfit. I use front tilt in 80-90% of my shots and front swing 10% (plus front rise and fall).Yes, movements will allow you to fully master DOF.
-- Jean-Marie Solichon (firstname.lastname@example.org), February 21, 2001.
Michael Make the Move!!! The control you have over depth of field is amazing!!But just the start, once you see an image on that big GG you'll be bitten!! For typical landscape work, the only movements I use are front tilt, and front rise/fall and sometimes rear rise/fall. As for choice of camera, IMHO I would tend to look for a modern field camera, maybe a used Wista? Get yourself a 90mm lens (my lens of choice in MF was 45 on 645 and 47 on 6x7/6x9) and I found the 75mm too wide. I use a 110XL and was surprised just how wide this lens is, but I think a 90mm would be a great choice.Dont have to worry about wide angle bellows either. Best of luck Paul
-- paul owen (email@example.com), February 21, 2001.
Tilting or swinginh the front or rear does NOT increase depth of field. Stopping the lens down increases depth of field.
Tilts and swings cotrol the plane of focus.
Think of an auditorium and you are on stage.
When you focus on a row all the sets across the row are sharp but not all the seats front to back in the room.
Tilt the lens (or the back if you want the shape of the chairs to chage) and you can have all the chairs from the front row to the back row sharp, wide open, but they will not be sharp across the row.
You have to now stop the lens down to increase the depth of field to bring the chairs across the row into focus .
-- Bob Salomon (firstname.lastname@example.org), February 22, 2001.
Thank you for all replys
-- Michael Mahoney (email@example.com), February 22, 2001.
Several responses said something to the effect that
"Tilting or swinging the front or rear does NOT increase depth of field. Stopping the lens down increases depth of field. Tilts and swings control the plane of focus."
That is true but fails to mention that the shape of the space inside the DOF limits changes radically with swings and/or tilts too. Instead of a rectilinear shape with a fixed camera, you get a wedge shape fanning out with ever-increasing width into your image. The greater the tilt, the narrower but more horizontal the wedge of DOF; conversely, 1 to 3 degrees of tilt gives you a very wide wedge the near edge of which intersects your tripod leg and far edge intersects the horizon! Hope you'll forgive my rhapsodic exaggeration!
Wish I could recommend a good single book explaining this aspect of LF but I don't know of such a book. Some of the main books I have looked at over the years deal with swings and tilts only superficially.
-- John Hennessy (firstname.lastname@example.org), February 22, 2001.
Actually, tilting does increase depth of field. Simultaneously, it also decreases depth of field. It just depends on where you are in the scene before the camera. Let me explain. If depth of field is measured along an axis perpendicular to the plain of focus, DOF will vary depending upon the distance from the camera. In near foreground areas, depth of field will be quite shallow. As distance from the camera increases, depth of field increases. At some particular distance from the camera (depending upon the tilt angle and the aperture) the depth of field will equal the DOF that could have been obtained by stopping down only. Beyond that particular distance, the DOF obtained by tilting and stopping down will exceed that obtainable by stopping down only. Theoretically, at an infinite distance from the camera, DOF will be infinite if a tilt has been used. Of course infinite distance is not achievable within our universe. I know that this might be a bit nitpicky, but it can be important to realize that actual DOF varies as the distance from the camera varies when a tilt has been used. The same principles also apply to swings.
-- Ken Burns (email@example.com), February 22, 2001.
As you can see, tilts and swings produce weird and wonderful effects on the plane of focus and depth of field. Harold Merklinger’s book, ‘Focusing the View Camera’ provides a good insight into this subject although it isn’t a particularly easy book to read.
Tilts can be very useful in certain ‘near-far’ type landscape shots where there is a single plane which you would like to be in focus but they may not be useful when there is more than one plane which needs to be in focus. For example, when you have a tall foreground object such as a tree. The use of tilts in this case may allow the bottom of the tree and the distant landscape to be in sharp focus but in doing so the top of the tree may well end up out of focus even if you stop down to a small aperture.
Some photographers use mainly front tilts whereas others prefer to use a combination of front and rear tilts. If possible try and get a camera with both types of movements and decide which you find best.
Although I love my large format camera, I regard it as an addition to my medium format equipment rather than an alternative. View cameras can do certain things extremely well (especially landscape and architectural photography) but they do have their limitations. Think very carefully before making a move entirely to large format.
-- Philip Y. Graham (PYG@plastsurg.com), February 23, 2001.
Merklinger has a web site at: http://fox.nstn.ca/~hmmerk/
You might find it interesting.
-- Ken Burns (firstname.lastname@example.org), February 23, 2001.
I once owned a Pentax 67, too. I sold it for a 4x5, and sold that for an 8x10. Yes, you can have sharp landscapes from inches to infinity with the use of tilt. The most useful movements are tilt and rise/fall for landscape use. Most landscapes need some front rise and tilt. If you want to use normal and wide lenses, and if you want a light camera, I would suggest a Tachihara 4x5. This camera is well-made, inexpensive ($550), and I like it better than the Wista (a similar camera at twice the price). If you want to spend more money, get a Wisner. This camera will allow you to use long lenses (450mm), but it weighs twice as much as the Tachihara.
-- William Marderness (email@example.com), February 23, 2001.