Lens Movement on a view Camera using 5x4 v Digital lens

[issa]

 A question for you guys.

I currently use 5x4 View camera and in the market for Phase one back 60Mp Sensor 53,9 x 40,4, Theoretically if I use a 5x4 and an analogue lens v  a digital lens with Digital back with the same angle of view and equivalent focal lens, What is the equivalent movement on the digital lens/back v a analogue lens on a 5x4.

For example on analogue they quote 54mm on 5x4 lens and 19mm for adigital lens on 53,9 x 40,4 sensor

Therefore what is the ratio between the two to give traditional users the same rise capability.

[Dick Roadnight]

I currently use 5x4 View camera

What camera do you have? how much rise/fall front and back?

and in the market for Phase one back 60Mp Sensor 53,9 x 40,4, Theoretically if I use a 5x4 and an analogue lens v  a digital lens with Digital back with the same angle of view and equivalent focal lens, What is the equivalent movement on the digital lens/back v a analogue lens on a 5x4.

With a 60Mpx back you will not get 60Mpx IQ with analog lenses, but some are better than others... analog lenses can give you very large image circles for large movements with digital.

You talk about format angle of view not lens angle of view?

For example on analogue they quote 54mm on 5x4 lens and 19mm for a digital lens on 53,9 x 40,4 sensor

Therefore what is the ratio between the two to give traditional users the same rise capability.

Who quote these figures, for what purpose?

Why do you want rise ¿parallel verticals in architecture?

If you use 26mm (half the sensor dimension) of rise on a 54mm sensor (with back vertical), the bottom of the picture will be at the same height as the camera, and with a 5" sheet of film you would need 2.5" rise, regardless of the lens.

Perhaps you could ask a more specific question relating to a specific situation?

[issa]

Hi Dick

Apologies if was not very clear. I don't plan using analogue lenses with digital back.

What I was after, if you had a digital lens on a digital back, what is the equivalent lens rise to analogue lenses.

If I plan to photograph a tall building using 5x4 and analogue lens, let us say you need 5 cm of rise, how much rise would you need on a digital lens and digital back, to photograph the same building with equivalent focal length and equivalent angle of view.

[Doug Peterson]

What I was after, if you had a digital lens on a digital back, what is the equivalent lens rise to analogue lenses.

If I plan to photograph a tall building using 5x4 and analogue lens, let us say you need 5 cm of rise, how much rise would you need on a digital lens and digital back, to photograph the same building with equivalent focal length and equivalent angle of view.

Just translate to % of the frame rather than cm of movement and everything will be much more clear.

5cm of rise on a vertical 4x5 piece of film is around 40% of the frame.
40% of a 53.9mm x 40.4mm frame is around 22mm of rise.

You can use our free Focal Length Converter to find the equivalent lens from your knowledge of 4x5:
http://www.captureintegration.com/2009/02/03/focal-length-equivalent-calculator/

If I could be selfish: I recommend you find and buy from a dealer who knows this stuff like the back of the hand. We've helped hundreds of photographers switch specifically from 4x5 to medium format digital and can help you avoid pitfalls, solve problems, and get the most out of your system.

Doug Peterson (e-mail Me)
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[Dick Roadnight]

Hi Dick

If I plan to photograph a tall building using 5x4 and analogue lens, let us say you need 5 cm of rise, how much rise would you need on a digital lens and digital back, to photograph the same building with equivalent focal length and equivalent angle of view.

What Doug says is correct,,, if the longer digital lens can do the job re lens field of view.

If you plan to photograph a tall building with verticals parallel (back vertical), the minimum lens field of view is twice the angle above the horizontal from the camera to the top of the building, regardless of film or sensor format, so "lens factors" for different formats might have little to do with this application.

(2* is only enough for a building with a point on top (e.g. a spire) so you can paint in the vignetted sky.)

If you have to shift 100mm of film 50mm to get the top of the building in, with a lens of the same field of view and focal length, you would have to shift the 50mm sensor 75mm, and then, presumably, stitch to get the rest of the building in.

75mm is the original shift plus half the difference in the format dimension.

[Doug Peterson]

What Doug says is correct,,, if the longer digital lens can do the job re lens field of view.

Yes of course. Thanks for that Dick - should have mentioned it.

The lens circles of both the 4x5 lens and the digital lens need to be taken into consideration. You have to have sufficient (and sufficiently sharp) image circle to shift/rise into. We have the lens circles of all potential lenses and the size of single-frames and stitched frames for all phase/leaf backs mapped in a visual document we provide to customers to help them figure out which lenses are best for them, along with a calculator that takes stitching into account.

[Dick Roadnight]

What Doug says is correct,,, if the longer digital lens can do the job re lens field of view.

Yes of course. Thanks for that Dick - should have mentioned it.

The lens circles of both the 4x5 lens and the digital lens need to be taken into consideration. You have to have sufficient (and sufficiently sharp) image circle to shift/rise into. We have the lens circles of all potential lenses and the size of single-frames and stitched frames for all phase/leaf backs mapped in a visual document we provide to customers to help them figure out which lenses are best for them, along with a calculator that takes stitching into account.

The maximum shift on 5*4 for the The Schneider Super-Angulon 90 XL is 50mm, as in the example, and the Schneider Super-Angulon 90 XL has the same field of view (92 degrees) as the Schneider Apo-Digitar 47 XL, so you might be OK as long as you chose one of the few MFD view camera lenses with generous fields of view/image circles.

[LiamStrain]

If you have to shift 100mm of film 50mm to get the top of the building in, with a lens of the same field of view and focal length, you would have to shift the 50mm sensor 75mm, and then, presumably, stitch to get the rest of the building in.

75mm is the original shift plus half the difference in the format dimension.

IF, however, you are looking to match the angle of view as well (e.g. using a 35mm lens, rather than a 90mm to compensate for the sensor size), then that shift is still best expressed in percentages, per Doug's example. Eg. a 40% shift (50mm in 4x5, 22mm in P65+)

[Dick Roadnight]

IF, however, you are looking to match the angle of view as well (e.g. using a 35mm lens, rather than a 90mm to compensate for the sensor size), then that shift is still best expressed in percentages, per Doug's example. Eg. a 40% shift (50mm in 4x5, 22mm in P65+)

Reality check, please...

Theoretically, yes, but the 35mm lens you might want to use is the Apo-Digitar 35 XL, which will not give you 22mm rise on a 53.9mm sensor!

If, in the real world, you used an Apo-Digitar 47XL, you might just about get 22mm rise on the 60Mpx sensor....

[Doug Peterson]

Reality check, please...

Theoretically, yes, but the 35mm lens you might want to use is the Apo-Digitar 35 XL, which will not give you 22mm rise on a 53.9mm sensor!

If, in the real world, you used an Apo-Digitar 47XL, you might just about get 22mm rise on the 60Mpx sensor....

True. You must be very aware of the image circles. A 43mm XL and a slight change of camera position (if possible) or a 32mm or 28mm HR with a slight change of camera position (if possible) might substitute. 

[LiamStrain]

Reality check, please...Theoretically, yes, but the 35mm lens you might want to use is the Apo-Digitar 35 XL

Yes, this was a theoretical only discussion. My point was not the specifics of which lens, but that if you are trying to match a 4x5 image and it's corrections with a smaller sensor, keeping things relational as a percentage of change is more useful.