What is hyperfocal distance for 210mm lens @f:64 (4x5 format)

[Bill_1856]

I don't seem to be able to find a chart for it. Thank you.

[Jay DeFehr]

24.32' Here's a calculator:

http://www.mountainstorm.com/HyperFocal/HyperFocal.html

[Witold Grabiec]

It should be around 24 ft.

Download this free f/calc applet from:

http://www.tangentsoft.net/fcalc/

This way you've got one on your PC for a quick reference.

[jerry brodkey]

I had downloaded fcalc and so my fcalc gives a value of 15 feet. The circle of confusion suggested by fcalc is 0.15mm. One of these programs seems off.....

[Bill_1856]

Thanks, Guys.

[Bob Salomon]

And you will be well into diffraction too.

[Witold Grabiec]

Bill,

I've just checked f/calc which I downloaded a couple of days ago. It gives me 24 ft. Make sure you have all veriables in order. Mine gives me a COC of ~ 0.09. COC of 0.15 does indeed give you some 15 ft on HD, but I had to enter this value manually.

By the way f/calc calculates COC as f/1730 and author calls it a "zeiss formula". COC is the key factor that affects HD or DOF calculations. As you can see from above it will make a substantial difference. I'm assuming however, that you need the HD to get maximum DOF. The higher the COC the more DOF you get, thus the closer the HD will be. Your COC of 0.15 is a bit high as it is usually listed in the 0.10 range, value also stated in the Applied Photographic Optics.

[jerry brodkey]

We probably have different versions of fcalc. My version is running on linux and when I click on 4X5 it puts in the value of 0.15 for the COC. When I manually enter 0.10 I get the same value as you get.....

[Bill_1856]

Thanks again, Guys. Please don't spend a lot of time on this. Basically I wanted the figure to check myself visually (since the GG image is so difficult to see distinctly when stopping the Dagor down to f:64). Visually, I got 25' which is "close enough for government work" as they say.

[Witold Grabiec]

Jerald,

It might help if you emailed the author of f/calc (something he's asking for) about the error. Yu can find his contact in the Help section of f/calc. I say error because the COC value of ~ 0.10 is the most frequently quoted for 4x5 in major publications on this subject (and my Windows version actually gets it right). It is likely a simple typo in the code. I would guess that all of your COC are off. For 6x6 you should be getting ~ 0.05.