My 7DmkII + 600mm + will not Focus with the 2XII extender [Archive] - BirdPhotographers.net

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Allen Kurth

12-15-2014, 02:49 PM

My 7DmkII + 600mm +2XII extender will not accurately focus. It also will not accurately focus a 400mm f4 lens with the 2XII extender. It is extremely soft – micro-adjustment doesn’t have enough range to focus it either. The 7DmkII works fine with the 1.4XII extender on the 600mm lens, an 800mm lens, a 400mm 5.6 lens and a 200mm f/2 lens.

I rented a 2XIII extender to see if the problem was my extender. The 7DmkII will not accurately focus with the rented extender either. I am able to sharply focus the same lens and extenders with a 1DmkIV.

Is anyone else using a Canon 600mm IS f/4 (version 1) lens and the version II of the 2X extender with a 7DmkII? I would appreciate knowing if I have a defective 7DmkII or if this is an undocumented feature.

Jason Holzworth

12-15-2014, 02:56 PM

Allen,

My 7D2 out of the box was defective. some people may say it's an user error, but there are many folks who returned their 7D2's for the same reason.

I sent mine to canon, had to wait 2.5 weeks for them to get the tool to japan to fix it, but when it came back it was producing tack sharp images.

i have used 70-200mm 2.8 L II, 24-70 2.8 L II, 200-400 w/ internal & external 1.4x iii and 600mm f/4 IS II w/ and w/o extenders.

before sending it into canon, nothing was sharp or what i would call in focus. after a canon visit, everything is good to go.

jason

Juan Carlos Vindas

12-15-2014, 03:40 PM

I have already used my 7DII with the 600f/4 (I) bare and with the 1.4 III TC. Everything seems to be right on the money. I don´t own the 2X though.

David Stephens

12-15-2014, 04:51 PM

It sounds like a problem with either your 2.0x TC-III or your new body. I should AF at f/8, although it'll be slower than with a bare lens or the 1.4x TC-III. I use the 500/f4 with the 1.4x and the 2.0x TCs with AF equally functional, just slower as you lower the native f-stop.

Paul Whitbread

12-17-2014, 04:56 AM

I take it can be focused to be as sharp as desired via live-view? (ie. it is a focus issue and not a softness issue)

Allen Kurth

12-19-2014, 09:14 PM

I take it can be focused to be as sharp as desired via live-view? (ie. it is a focus issue and not a softness issue)

It can be focused in live view.

Diane Miller

12-20-2014, 01:48 PM

Sounds elementary, but have you tried cleaning the contacts?

arash_hazeghi

12-30-2014, 07:34 PM

It would be easier to help you if you could post 100% samples.

The old extender 2X II is not that sharp. I doubt if it can deliver files that are sharp at pixel level when coupled with a small pixel camera like 7D2. I would recommend using a 2X extender MK III instead.

Robert Hardy

12-31-2014, 04:58 PM

you are putting the tc on the lens first Not on the camera .

Rob.

Fred Woodman

12-31-2014, 07:27 PM

you are putting the tc on the lens first Not on the camera .

Rob.

does it matter if you attach the teleconverter to camera before the lens ?

arash_hazeghi

12-31-2014, 08:08 PM

despite Canon's recommendation, I have never noticed a difference in the order of the attachment. The extender often stays mounted on my camera and then I attach the lens. This is true for any Canon camera/lens combination

Robert Hardy

01-01-2015, 10:36 AM

Says in the manual well with the mkIII tc,s First attach the Extender to the lens, then attach it to the camera. To detach it, follow the same procedure in reverse.

Rob.

Diane Miller

01-01-2015, 12:07 PM

I usually do it this way, just because it's more convenient, but I wonder if some rationale is available for this. Normally the camera would be off when swapping lenses -- if so, how could the order matter? If it does, is it something electronic that could affect focus, or just the safer thing to do mechanically?

Moe Ali

01-02-2015, 02:20 AM

Just to be safe I would opt to putting the tc on the lens first and then placing the combo on the body. Even with the camera switched off there is still power running through the unit. You would have to pull the battery to be safe. Try changing a flash card while the camera is turned off and you'll notice the red indicator light flash a few times. So the camera is still doing something even when turned off. Otherwise why would Canon make the recommendation?

Moe Ali

01-04-2015, 11:59 PM

I have more evidence regarding the importance of attachment order when it comes to TC and lens.

I own both a 1.4x kenko pro teleconverter and a 2x mk II Canon teleconverter. There is a huge issue with the kenko teleconverter and microadjustment settings on my Canon 7D mark II.

Under the menu selection "AF Microadjustment", there are 3 selections:

1.) Disable
2.) All by the same amount
3.) Adjust by lens

My kenko requires a +10 adjustment with one of my lenses and so I need to use microadjustment. The Canon 7D does not detect the Kenko and so I need to use option 2 "All by the same amount" in order to apply microadjustments to the kenko and lens combo. But here's the huge issue with the kenko….. if by mistake I have option 3 set "Adjust by lens", the camera's autofocus locks up and stops working when the kenko is attached. The only way to resolve the problem is to remove the battery, followed by removing the kenko+lens combo, reattach just the Canon lens, insert the battery and then turn on the Camera.

Now here's how I tested the importance of your TC and lens order when attaching it to your camera body, even when the camera is turned OFF.

I placed my 2x mark II TC and lens on the 7D II and set option 3 for microadjustment. Took a few shots with the camera to ensure things were working fine. I turned off the camera, removed the tc+lens combo and then put the Kenko+lens combo on the camera body. I placed the combo back on the camera while it was OFF. I did NOT turn on the camera. I simply placed the kenko and lens combo on the camera and then removed them without turning the camera on. If the camera is truly off it wouldn't care what combo I placed on it and removed until I turned it on…… WRONG.

I then placed the 2x Canon TC + lens on the camera and turned it on. The camera's autofocus froze!!

So the camera detected the kenko even when turned off, because it triggered the autofocus freeze. I was able to repeat this issue over and over consistently. It seems that the camera body checks your lens combo when you attach them while turned off. My kenko tripped the focus issue on the Canon even when it was turned OFF!

I wonder now if you attach your Canon TC to your body first are you potentially screwing up your AF microadjustments. If you attach the TC alone it triggers the camera to check the combo, so if you attach the lens afterwards it won't know because the lens doesn't trigger the camera to do another check.

It might be fine when you turn it on, but you might be compromising your AF microadjustments, which could then compromise your focusing accuracy. Or maybe it just throws the whole system into a loop. Who knows, but play it safe.

I think this goes to show that Canon recommendations have a reasoning behind them. They know their equipment.

TC onto lens first, then combo onto body second.

Diane Miller

01-05-2015, 12:10 AM

Excellent information -- thanks for the work! I'm always the skeptic who wants to know WHY I should do something. But I have normally done it the "right" way, just because it's ergonomically easier. It's been rare that I have ever swapped lenses with the TC on the body, but I'll be sure not to in the future.

arash_hazeghi

01-05-2015, 12:30 AM

I think this only proves why you shouldn't use a cheap third party TC with your canon gear. During the past 9 years of working with many Canon lenses and extenders (can't count how many) I have never seen such issue. My TC's always remain on the body.

MA setting remains regardless of attachment order as long as you use Canon lenses and TC's.

Note: Canon discourages using third-party accessories with your canon camera and lens. They are not officially supported nor covered by warranty. As an extreme example if you attach a kenko TC to your camera and it fries the AF circuit it won't be covered under warranty and you will be responsible for all damages. Don't risk it :S3:

Moe Ali

01-05-2015, 04:53 PM

I agree that third party TC's and lenses might not be ideal when combined with say Canon or Nikon. Especially if you're a perfectionist, you only want the best. And I'm sure Canon would love it if we all bought just their products... :bg3:.

But that's not the point I wanted to lend to the discussion. Like Diane I'm also wondering what the rationale is behind Canon's recommendation. Is it just so we safely attach our lens and combo, or is there a functionality issue?

I simply wanted to point out that your camera is still "on" even when off and can detect camera lens attachments. So being an Engineer my inquiring mind now wants to know if this has an affect on the TC to lens mounting order. Since my last post further research has pointed me to one person who spoke to Canon regarding this very issue. All they could tell him was that by following the recommendation this would ensure peak AF performance. And mind you he was probably talking to some Canon rep who had nothing to do with designing the product.

Now I don't know if there's more in that reasoning, but if you've adjusted your lens using MA by say +/- 5 units, then maybe you wouldn't notice if those adjustments were being applied properly due to the improper registering of the combo as a unit. Maybe people who don't apply MA don't have to worry about TC and lens order.

I don't know, but I'm just adding some food for thought to the discussion. Maybe someone knows a Canon Engineer that could give us insider information on Canon's black box :S3:..... I'd love to know.

arash_hazeghi

01-05-2015, 06:01 PM

The poster is not using a third party TC, I doubt if his issue has to do with MA or order of attachment. He mentioned his images are extremely soft.

As I mentioned I have never seen any kind of issue from the order of attachments including loss of MA settings, but I never use third party lenses or TC's. So that's all I know...

Moe Ali

01-05-2015, 11:11 PM

Looks like we went off course Allen, but I think your initial question sparked some interesting stuff. And I do understand you're not using a third party teleconverter, that wasn't the point of my test (I'm starting to sound like a broken record Arash :w3).

Sorry for taking your initial question off on a tangent.

I don't have the 600 f4, but I do have the 300 f4 IS lens, and a Canon 2x II extender. I've tested the combo with my Canon 7D mkII and they work fine.

Without going into too much detail, basically I setup the combo on a tripod and did a manual focus using live view (10x zoomed). I then took an image of the target and then switched to normal focusing and took multiple shots from infinity. It focused slow but 9 out of 10 times it would be right on the money. My combo needed a very minor +5 micro adjustment. It's good enough for my low standard type of photography :c3: (it's just a hobby!).

I would think that your 600 f4 would do much better than my 300 f4. And since you also rented a MK III tele to further narrow things down, I wouldn't be surprised if the problem was in the 7D II focusing. Apparently the centre focus point can be faulty, so I would have your camera checked or returned.

Here's an image of a Killdeer with the 300 f4 + 2x combo on the 7D II, hand-held in poor lighting conditions. Original image was underexposed, and I had to crop the image 50%. This little gal (I'm guessing female) wouldn't let me anywhere near her.

Canon 7D II + 300 f4 IS + 2xII: ISO 800, F9, 1/500

http://moesphotohobby.weebly.com/uploads/2/5/4/7/25475992/687008_orig.jpg

Luis Rodrigues

02-19-2015, 11:50 AM

Is anyone else using a Canon 600mm IS f/4 (version 1) lens and the version II of the 2X extender with a 7DmkII? I would appreciate knowing if I have a defective 7DmkII or if this is an undocumented feature.


Hi, I'm using a Canon 600mm non-IS f4 and the 2x extender version II, and also the 1.4x extender version I, with the 7DII. All works well and the results are very sharp. But only after I've micro-adjusted for the lens and the lens with the extenders. Before it was a light soft. Also, with mine, they only autofocus if I attach the extender to the lens first. If I attach to the body first it will not autofocus, automatically switches to manual focus.