"Q" symbol getting disabled and autofocus issue in Canon 7D mark ii reg...

[gopi_lakkala]

Hello Friends ,

                 Greetings - I am using Canon 7D mark ii from one year with Tamron 150 - 600mm G1 lens, it was working good and fine. Recently i purchased Canon 400mm f/2.8L is ums used lens from other sources. Once i install this 400mm prime i came across an issue which is new to me and people who knows. The issue is Q symbol is getting disabled and even i cannot able to review the clicked images as my screen is completely getting blank. once i switch off and switch on all the functions will work for a while around first 2 - 3 mins and the same issue repeats. So i cross verified with other lenses it is working fine and did the 400mm lens with other canon bodies like 6D , 6D mark ii, 7D. So i got a conclusion that lens is creating problem. does any one faced the same issue or need feedback what could be the issue with the lens. leaving this autofocus issue lens is performing absolutely fine in manual focus mode and delivering great images.

                  Requesting friends to help me out to sort out the issue.

Thanks and Regards,

Gopi. L

[Ray-uk]

It is quite possible that this lens is a bit more demanding as regards your battery. I would suggest you try a different, preferably new battery in your camera before doing anything else.

[wq9nsc]

Follow Ray's suggestion and try a new battery, you might also try turning IS off on that lens to see if your current battery behaves differently with the reduced current demand.

If you are using an aftermarket battery, that can also be an issue because they often cannot source the same current level as the OEM batteries without suffering to much voltage drop.  I needed new batteries for my 1DM2 several years ago and I couldn't find Canon batteries in stock so I ordered a pair of highly reviewed after market batteries.  They appeared to charge and work properly UNTIL the 1DM2 was used for high speed sustained bursts and the camera would lock up after a few frames.  Proper Canon batteries restored it to normal service.

I have the IS II version of the 400 f2.8 and it is a wonderful lens.  Much of the time I have IS turned off because I am shooting at very high shutter speed but it does work well when needed.  Focus acquisition speed is incredibly fast but you will need to check the micro AF adjustment for your camera because shooting this fast 400mm lens wide open even at a reasonable distance results in a very shallow depth of field and the AF calibration has to be spot on.

Rodger

[gopi_lakkala]

Hello Rodger,

                Will try with new once and will update for any imporvement. However i have two i have two original Canon make batteries. i had problem with both the batteries. i suspect the UMS may have any issue because for first 3 mins it works well after the it is hanging. one more point is when the issue araises, my live screen, iso adjustments and image preview will stop working. So i posted for help. If any one can me in sorting out the issue.

Thanks and regards,

Gopi. L

[wq9nsc]

Hello Gopi,

I believe that your screen not displaying, Q button not operating, etc. are all related to the lock up which is keeping the image from being displayed.  The camera is trying to display the preview image and when it is unable to do this it stops the entire process freezing the controls and other camera processes.  The same will happen with some other Canon bodies when you aren't in live view and the camera is unable to display the sample image after capture.

Hopefully this is all related to a power issue from older batteries.  And although the battery contacts are somewhat self-cleaning, before you install a new battery carefully clean the battery contacts within the camera by wiping them gently with a foam or cotton swab moistened with the highest concentration isopropyl alcohol you can find.

I wasn't clear from your first post, but is your 400 f2.8 functioning OK on other camera bodies?

Rodger

[gopi_lakkala]

Good morning Rodger,

        Greetings - First of thank you for all your intrest in taking time to suggest me. However i have not tried with the camera bodies mentioned by you - "EOS 1DX M3, 1DX M2, 1DX, 5DS R, 1D M2, EOS 650 (film), many lenses, XF400 video", I just tried in EOS 7D mark ii, 7D and 6D bodies only.

         Yesterday i got new battery grip BR-E16 and installed the same on my 7D mark ii body with 2 fully charged batteried. first i tried the combo with IS off and found perfectly alright for 10 to 15 mins. Once i switchd ON the IS then also it worked for 5 mins with very fine and again the same issue was repeated. i orderd new branded Canon LP-E16 batteries in Amazon which is expected on Saturday (i,e 06.02.2021). i will install the same set of batteries on the battery grip and will do the field test and share you the feedback on the same.

Thanks for the special intrest in helping needy...

Thanks and regards,

Gopi. L

[wq9nsc · Accepted solution]

Good evening Gopi,

I am sorry that I wasn't clear in my previous communications but I was asking whether the lens worked OK on your 7D and 6D bodies.  If it works properly on those bodies, then it is unlikely that the lens is at fault and it is something associated with the 7DII.  If it is working OK with the other bodies, make sure that you have the latest firmware installed in you 7D II because there have been at least some cases where Canon issued firmware updates for some bodies to resolve issues with some lenses.

I hope that the new batteries will let this combination work for you.  It is a wonderful lens.

And something else to try, if digital lens correction is turned on in the camera then try turning it off to see if that makes a difference.  The digital lens optimization uses a lot of processing overhead so maybe it contributes to the issue.  I shoot only in RAW and leave lens optimization turned off in the body and apply it after I import the RAW images into DPP.

Rodger

[gopi_lakkala]

Good morning Rodger,

                  Thank you for your help and sort out the issue. As suggested we replaced new batteries and disbled lens correction, then it is woring absolutly very good and every aspect is ultimate.

                 Thanks a lot for helping out me to come out of this headache. 

  Note : I have one opetion in the lens call focus preset, can any one sugget how to use it or can any one have video which guids us to use it.

Thanks and regards,

Gopi. L

[wq9nsc]

Good evening Gopi,

I am glad that you have the lens working!

You can find the manual for your lens here if you did not get it with the lens, the 300, 400, 500, and 600 fast primes of this generation had a common manual.  It explains how to set and use the preset focus system:  https://www.usa.canon.com/internet/portal/us/home/support/details/lenses/ef/telephoto/ef-300mm-f-2-8...

I have never found much use for preset with what I do but you may find shooting situations where you need to instantly return to a specific focus point.  Unless you are shooting from a tripod or want to be able to go instantly from a closer focus to infinity, it probably won't be something that you use often.

Rodger

[gopi_lakkala]

Hello Ray-uk,

                    i tried that option also. I have two batteries with me which are OEM make, not the aftermarket once. even i tried with other battery in place the situation is same. One point i forgot to mention is... in that situatuation my live screen, iso selection and image preview are also not working.

                  Can we use battery grips for further simulation and to get conclusion on power utilization.

Thanks and regards,

Gopi. L