FoCal

Kodiak Qc said:
What ever goes wrong with the ruler WILL also go wrong
with focal… it is a ruler!!!
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It won’t. There is so much scope for making mistakes with a ruler. With Focal it does it all for you and won’t work unlesss it’s happy.
 
Kodiak Qc said:
I mean…

  1. set a ruler anywhere between 45~60! on a table
  2. set camera on tripod and levelled
  3. use the centre AF point and aim at a number on the ruler
  4. tether to computer
  5. get to the minimal focusing distance, AF and shoot
  6. the target should show in focus and an equal number of lines before and after
  7. if no, either it is front of back focus
  8. compensate as necessary
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The most inaccurate way of doing it !!!!
 
Kodiak Qc said:
I mean…

  1. set a ruler anywhere between 45~60! on a table
  2. set camera on tripod and levelled
  3. use the centre AF point and aim at a number on the ruler
  4. tether to computer
  5. get to the minimal focusing distance, AF and shoot
  6. the target should show in focus and an equal number of lines before and after
  7. if no, either it is front of back focus
  8. compensate as necessary
Click to expand...

Nope that’s poor advice. Sorry.

The camera focus points are too large to be able to accurately focus on a ruler marking with consistency. This is why kits like lens spyder have a larger central area to focus upon so you know exactly where’s the camera is focusing.

Kits like lens spyder are poor because the user still has to squint at the results and try and determine which line/number is sharpest.

Focal just does it all for you and spits out the number.

Secondly you say minimum focus distance. Typically a lens on a camera body can only be adjusted at one focal distance so it’s best to set the distance at what you typically shoot. Mfd may suit a macro lens but not much else.

Of course if your lucky enough to have sigma or Tamron lenses rather than crappy oem ones you can adjust for all focus distances and all focal lengths.;)
 
Kodiak Qc said:
These reactions are justified as I mistook LENSCAL that I use
for FOCAL that I don't. Sorry for that! :banghead:
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Gracious apology accepted. however it doesn't excuse the flawed advice of focusing on a ruler angled at 45 degrees at the MFD of the lens....
 
PhilH04 said:
it doesn't excuse the flawed advice of focusing on a ruler angled at 45 degrees at the MFD of the lens....
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Sorry again but this time, Phil, I describe the well experienced
used of the Lenscal not all of my students can afford — which
is btw a ruler at 45°. :cool:
 
Kodiak Qc said:
Sorry again but this time, Phil, I describe the well experienced
used of the Lenscal not all of my students can afford — which
is btw a ruler at 45°. :cool:
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LENSCAL does have a ruler but it is not used to focus on, there is a flat focus chart that you should use to focus.... Cheap alternative is to still use your ruler at an angle but placed next to a focus chart (suitable for your AF system), the chart should be parallel to the sensor plane... Bearing in mind that it may not be accurate to the nth degree...
 
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sep9001 said:
Hi

Sorry do you have to buy the hard target or can I use one that has been printed on a normal paper via a laser printer?

Thank you
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You can use a printed target but I highly recommend the solid one from Focal as it helps keep the target level and therefore less likely to confuse the software when it tries to find/use the target. Focal works very well when used properly (good light, solid support, level with the target) as it takes out the 'human element' which can add further variations.
I recommend Focal Pro :)
 
gramps said:
You can use a printed target but I highly recommend the solid one from Focal as it helps keep the target level and therefore less likely to confuse the software when it tries to find/use the target. Focal works very well when used properly (good light, solid support, level with the target) as it takes out the 'human element' which can add further variations.
I recommend Focal Pro :)
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Thank you, can I print and mount on a board or should I order it with the target. It is £55 with the target and £39 without...
 
sep9001 said:
Thank you, can I print and mount on a board or should I order it with the target. It is £55 with the target and £39 without...
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Honestly I would buy the target as it takes out the 'you' (or me in my case) but you can print and mount if you prefer the cost-saving :)
 
Right tried the ruler method with the camera connected to the MacBook and I could not see any difference, so have bit the bullet and bought focal.

Now just need to make time to fine tune the lenses and hope it works out...

Thank you all.
 
You can also use Focal without any target such as a far away building when testing for infinity. (say for sigma/Tamron docks) It will still work!!
 
The advice, if you are printing your own targets, is to make sure that you use an inkjet printer and not a laser. All to do with how they reflect light. I tried both, just out of interest, and it didn't make any difference to the results.
 
Spent 2 hours trying to do a few of the lenses I have, 50mm was straight forward, 28-105 also seem straight forward, got a reading of -5 at 28 and -10 at 105, so set it at -7.

The main reason for getting focal was for my Tamron 28-75f2.8, worked fine at 28mm got -1 but could not get it to work at 75mm, said it was out of range. :(

When I did it with dot tune method I had it set at -2, so not that far out using focal, at least at 28mm.

Had to use two studio lights to get enough light, might have to try outdoor and a better sunny day.

Thank you
 
sep9001 said:
Spent 2 hours trying to do a few of the lenses I have, 50mm was straight forward, 28-105 also seem straight forward, got a reading of -5 at 28 and -10 at 105, so set it at -7.

The main reason for getting focal was for my Tamron 28-75f2.8, worked fine at 28mm got -1 but could not get it to work at 75mm, said it was out of range. :(

When I did it with dot tune method I had it set at -2, so not that far out using focal, at least at 28mm.

Had to use two studio lights to get enough light, might have to try outdoor and a better sunny day.

Thank you
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I always do it outside(!) but if you use the lenses for studio work then inside plus lights seems sensible.

I have had lenses outside the parameters of the -20/+20 namely the Nikkors 50 and 85 1.8G.

Not a lot you can do really bar sell them on eBay...
 
Brazo said:
I always do it outside(!) but if you use the lenses for studio work then inside plus lights seems sensible.

I have had lenses outside the parameters of the -20/+20 namely the Nikkors 50 and 85 1.8G.

Not a lot you can do really bar sell them on eBay...
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Thank you, will try out door. What is best to use as a target please?
 
Brazo said:
I printed them at A3,4,5
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Printer I have at home only does A4 at the largest size, I can do A3 at work but would have to roll or fold it to get it home. :(
 
A4 should be fine for most lenses. The larger targets were a pain at mfd and a5 proved better so don’t worry!
 
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