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Arca Focus Calculator V001 Beta - iPhone/iPad version

jagsiva

Active member
Please consider this a Beta version and ensure you test with your lenses. You can post any suggestions and feedback here as well. This runs on Numbers which can be downloaded from the Appstore. It was much easier to do this than build a standalone app that would have to go through Apple's onerous publishing process.

Two files attached below containing the application and instructions.

1. Rodie 23HR - I have tested with my lens
2. Rodie 32HR - I have tested with my lens
3. Rodie 40HR - I have tested with my lens
4. Rodie 90HR-SW - I'll have my lens next week, so will add shortly
5. SK35XL - Not tested as I don't have the lens anymore. Supported based on chart data only
6. SK43XL - Not tested as I don't have the lens anymore. Supported based on chart data only
7. SK 60XL - I have tested with my lens
8. SK 120ASPH - I have tested with my lens. The chart data I had was not quite accurate, so I took actual measurements. The lens also focus shifts quite a bit, so I and to use multiple formulas for different distance ranges.

First file - Calculator in Zip
Second file - Instructions in Zip
View attachment 83407
View attachment 83408


 

miska

Member
Would it be possible to add lenses to your database (even with lower accuracy) ? So is it enough for you to have the data from the "magic focusing card" from Arca-Swiss for a given lens ? Or do you need some actual measurements ?
Getting rid of those cards would be quite nice (and scanning them into the iPhone is not that convenient either).
 

jagsiva

Active member
No problem to add lenses:

1. Just post the chart data here. If the lens needs a back extension, please include the length of the extension.
2. Generally speaking, the more data points, the more accurate the formula will be. Just let me know the measured distance, and from where you measured it. Also if there was a back extension and what its length is.
3. I'll create a tab with just the lookup charts. That way they can be in one place and provide an alternative to the formula calculation.
 

jagsiva

Active member
BTW, looking for feedback on how distance is entered into the calculator. I want to be able to do it with one hand, so minimal typing. Using a single field stepper takes too long at 0.01 accuracy, hence the breakout into 3 fields. The current method is a little cumbersome, so if anyone has any ideas let me know.
 
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