600mm F/4L IS AFMA settings

[Pieces Of E]

Yup, the camera is tethered to the computer for FoCal. It's fully automated for Canon as far as I can tell; for my Nikon I have to manually set the AFMA for each shot and tell the software to take the photo... much more inconvenient.


In order to use the FoCal software, the camera HAS to be tethered to a computer? Then how are people like Neuro calibrating a 600mm lens at lengths up to 98 feet? Is this a USB cable? Please advise, thank you.

 

[rpt]

light variability due to clouds

This is exactly why I took it indoors and did it at night. Total control of the light intensity! Back to the drawing board for me now. And I will have to cajole the wind and cloud gods

It is not very gusty to shake the camera. The target is another matter...

So be it!

 

[rpt]

Yup, the camera is tethered to the computer for FoCal. It's fully automated for Canon as far as I can tell; for my Nikon I have to manually set the AFMA for each shot and tell the software to take the photo... much more inconvenient.

Same here for the 5D3. You have to be careful not to displace the camera.

In order to use the FoCal software, the camera HAS to be tethered to a computer? Then how are people like Neuro calibrating a 600mm lens at lengths up to 98 feet? Is this a USB cable? Please advise, thank you.

The target is at 98'. One does not need to be near the target. Just near the camera and the computer. And yes, it is tethered by the USB cable that comes with it - at least that is the case with my 5D3. Dont know about Nikon but I cant believe it will be any different.

 

[Loswr]

In order to use the FoCal software, the camera HAS to be tethered to a computer? Then how are people like Neuro calibrating a 600mm lens at lengths up to 98 feet? Is this a USB cable? Please advise, thank you.

To run in full auto or MSC mode, it must be tethered. In my case, I actually just took all the shots of the target manually, then loaded them into FoCal for their manual analysis. I loved the fully automated analysis with the 5DII and 7D, but with the 1D X since I have to stand at the camera anyway to manually change the settings, it's not a real time saver to run in MSC mode. Taking the 83 shots per run takes me about 10 minutes (I shoot 2 shots each at even number AFMA value from |20| to |12| and 3 shots each at all values from +10 to -10; that also allows me to manually defocus in both directions, so AF is done from both the MFD and ∞). Yes, I oversample relative to what the MSC mode would do, but it's no slower and I get nice curve fits.

 

[Pieces Of E]

Thanks rpt, I had realized my question didn't make sense after I wrote it. I wasn't thinking clearly about the setup. I guess my mind was on the 400 million+ dollar powerball lottery being picked tonight. Just the target has to be said feet away, camera and computer can be close and tethered. sorry

 

[Pieces Of E]

As you all can also see, I don't know how to put previous quotes into boxes on my replys. :-[

 

[rpt]

Thanks rpt, I had realized my question didn't make sense after I wrote it. I wasn't thinking clearly about the setup. I guess my mind was on the 400 million+ dollar powerball lottery being picked tonight. Just the target has to be said feet away, camera and computer can be close and tethered. sorry

Well, if you win I expect a share of $1.00 from that lottery for my hard work...

 

[Pieces Of E]

I won't forget ya. Imagine the freedom to buy all the camera gear you want and having the free time to shoot the world. Damn. 8)

 

[East Wind Photography]

I just picked up an Induro 414 so that might help with the stability issues. My existing tripod is way undersized for a 600 and my Vblock setup for smaller tests wont accomodate the 600. Obviously the higher the focal length the more susceptible the tests are to vibration and angular motion. I was seeing significant vibration during shots even when using mirror lockup or quite mode. I also need to make sure the shutter speed is as high as I can get it.

Have you tried running tests at higher ISO or should we stick with using 100 for all tests? I can see with the 2XIII the tests will require a couple of suns worth of light.

I test all lenses at both 25x and 50x the focal length, and I use the standard FoCal target. So, for a 600mm lens that's 49 ft (15 m) and 98 ft (30 m). Since I'm using a multiple of the focal length, the target size in the image is the same with any lens (e.g. 24mm at 3.9' is the same FoV as 600mm at 98').

I suspect your problem is either having too much vibration and/or not having enough light. How stable is your setup and what was the EV reported for the test?

When I first started using FoCal, I ran tests on the main floor of my house (hardwood floors), and I had several failed tests. I moved the setup to the basement (concrete slab) and had none. Also, I use lots of light - I point three 150 W-equivalent gooseneck lamps at the target from a distance of 12-14", and my reported EVs are in the 11-12 range when I test indoors. For my 600/4 II, I ran the test outdoors in direct sunlight, and still had the 3 150 W-equivalent lamps pointed at the target, so my EVs were in the 15-16 range. That gave me shutter speeds of 1/1250 s with the f/5.6 combo with the 1.4xIII. I still haven't done the 600 II with the 2xIII testing - I need to find a vacant football field for that...

 

[Loswr]

I just picked up an Induro 414 so that might help with the stability issues...

Have you tried running tests at higher ISO or should we stick with using 100 for all tests? I can see with the 2XIII the tests will require a couple of suns worth of light.

I've got a rock-solid tripod and gimbal head.

I've shot some at ISO 200, it works fine. But I did my outdoor testing in direct sunlight and added 450 W-equivalent of halogen lighting, so even at f/5.6 my EVs were in the ~15 range. That was giving me a shutter speed of 1/1250 s at 840mm with the 1.4xIII. I haven't done the 2xIII yet, but assuming I have 15 EV of light for that, I'd probably use ISO 200 to keep the shutter above 1/1000 s.

 

[Pieces Of E]

I wasn't one of the 2 lucky stiffs that won the lottery last night.

 

[rpt]

I wasn't one of the 2 lucky stiffs that won the lottery last night.

I was not a winner either. Don't worry about it. The best way not to loose a lottery is never to buy a lottery ticket!

 

[East Wind Photography]

So with that said, it's time to pull out the credit card!

I wasn't one of the 2 lucky stiffs that won the lottery last night.

I was not a winner either. Don't worry about it. The best way not to loose a lottery is never to buy a lottery ticket!

 

[GMCPhotographics]

Neuro and wearle are on the money. The only thing I'd add is DO NOT USE FLUORESCENT LAMPS OR TUBES. Sorry for shouting it out but it has been one of the significant reasons my tests failed. Also never raise the central column of the tripod.

Best of luck

Every single light in my apartment is fluourescent... No wonder FoCal kept giving me inconsistent results. Good to know! I might pick up some cheap lights and then return them afterwards.

It is a real pain. I did it 4 times before realizing it was the fluorescent bulbs! Each time the error would come at a different part of the process. I even wrote to FoCal earlier telling them that I have feedback for them - and that really turns out to be user error! When I changed the bulbs to incandescent, everything worked perfectly!

Guys, please use daylight to calibrate....not artificial lighting. Unless you intend to use that colour temp of lighting to regualrly shoot with. Tungsten lighting will cause minor red light shift errors in AF and Flourcesent lighting pulses at 50hz....which will really confuse the AF system. Some flourecent tubes are tri-tubes which phases at really wild frequencies and they are the worse to attemt to AF with. So do your self a favour....calibrate it in the best light....the natural stuff. If you can't do it during the day time due to work patterns, then take it out on a saturday or sunday and set it up then. If something is worth doing, it's worth doing well.

 

[jonathan7007]

I started outside a couple of weeks ago and although my tripod is super steady (old aluminum Gitzo Tele Studex 5-section model that must weigh 20-25 lbs) the wind was moving the board on which the target was pinned. Big light stand but too much "Sail" area. It's always windy here in the middle of the Pacific where the trades blow in after last touching land 3,000 miles northeast in California.

Two light stands with weights might work so positioned as to allow the clamps to attach to each side of the mounting board... also smaller board area around the target. I have a 300 to test in the mix so some distances involved. Wish that Mk3 test wasn't crippled by Canon's software interface.

I can't really whine about this as the opportunity to test this independently on a lens-by-lens basis is terrific.

jonathan7007

 

[East Wind Photography]

You can get full page address labels at staples or Office Depot. You can just stick it to a piece of plywood or on the side of your neighbors house that you don't like. I paste them on foam board but any rigid surface would work.

I started outside a couple of weeks ago and although my tripod is super steady (old aluminum Gitzo Tele Studex 5-section model that must weigh 20-25 lbs) the wind was moving the board on which the target was pinned. Big light stand but too much "Sail" area. It's always windy here in the middle of the Pacific where the trades blow in after last touching land 3,000 miles northeast in California.

Two light stands with weights might work so positioned as to allow the clamps to attach to each side of the mounting board... also smaller board area around the target. I have a 300 to test in the mix so some distances involved. Wish that Mk3 test wasn't crippled by Canon's software interface.

I can't really whine about this as the opportunity to test this independently on a lens-by-lens basis is terrific.

jonathan7007