Hi Andy, I actually do think it is still worth it. It was also one of the later EF super teles in terms of design, although obviously more of a Version II lens than Version III. I did find it worked very well with my Canon R6 and R3 bodies. I also still have two folk that travel often with me using their EF 400 f4 DO IS ii lenses paired with the EF-RF adaptor and Canon R5 bodies. I also found that this lens worked well with the 1.4x extender on my Canon 1DX2 and 1DX3 bodies but exceptionally well when I used an R3 instead of the 1DX bodies. With an extender the R5 worked almost as well when it came to autfocus. Unfortunately I have little to no idea of the UK used camera and lens market so i don't know if that price is high or not. A mint condition lens would be great.

@@grantatkinson8108 Thanks Grant, that is really useful. I think I will wait until I find one in good condition and go for it. I have checked with Canon and they do still service the lens although they have said they can’t say how much longer for.

Hi Grant, just a quick update for you. As a result of your very helpful review and advice I have purchased a used 400 DO ii and after a few days of testing, I am delighted with the lens. I can’t believe how (relatively) light and small the lens is and I am very pleased with image quality and bokeh. Image quality at f4 it’s pretty good but improves greatly at f5.6. I am also pleasantly surprised at how well the lens works on my Canon R7. Various reviews are not very complimentary of this lens/camera combination. Once you start pixel peeping you can see that the image quality is not as good as on the R5 (which is to be expected) but it is quite acceptable and hardly noticeable until you zoom in to 100%. Still a good lens in 2024!

@@andygray7776 I appreciate you coming back to this post to give us that feedback coming from using the EF 400 DO IS ii with the latest Canon camera bodies adding more relevance. Am also really glad you are enjoying using your 400DO and hope you are going to get lots of strong images with it!

Try updating it no clue if that's why but just a recommendation

same dude

I never managed to see a tangible difference with Dual Pixel Raw but maybe i never had the right scenario. I would still do any of those adjustments that I turned off afterwards if they where still required?

I have both, mk 1 is sharp, mk 2 slightly sharper, I prefer the push pull zoom, my mk 3 1.4x converter only works with the mk 2 auto focus

@@eldergeek9416 I rent Mk1 serval times during air show - push pull zoom reacts quicker to capture fast moving airplanes but people also say it's also easier to get dust inside.. 🤔 but all the online review articles say that Mk2 is much better than Mk1, but it's also significantly more expensive on ebay.. I'm not sure if it worth the extra to get Mk2..

@@eldergeek9416 I want to use the 100-400mm lens for airshow, I hired the Mk1 before and I quite like the push pull zoom because it's really convenient to change focal length when aircraft is approaching. I guess at my skill level, the Mk1 is probably more than enough..

@@hpwan2 The push pull is great for approaching aircraft, also depends on the camera body and what AF method your are using, quite similar to Birds in flight

happy to read that it is still useful!

Image quality, there is some small improvement in detail with the Mark II lens evident, as well as fewer occasions when the backgrounds might come out a bit "nervous" but image quality evaluation depends upon how critical the final images are viewed. If you are shooting in-camera jpegs you might not notice much difference in image quality at all. But for my own use the more reliable and more accurate and quicker autofocus of the Mark II made the biggest difference.

@@grantatkinson8108 thank you, I only shoot RAW… But I expected the image quality to be a vast improvement on the previous lens since the MkI has been out many years…

@@conservative-proud for sure image quality can be perceived differently by different users, but the original push-pull Mark 1 IS was always an L lens and if i recall correctly, it had flourite and UD lens elements. So i consider it to have decent image quality to start with. In my opinion, the EF 100-400 IS ii has a small improvement in image quality over the Mark I IS but if that improvement is significant depends upon the users personal requirements. Both of the lenses met my needs for image quality when I was using them. I do still use an EF 100-400 IS ii in my work.

Hi Anand, its a great lens. I used to use mine often with the 1.4x iii mounted on it. With the 5D Mark 4 there is only really a slight slow-down of the Autofocus speed in some situations, but I would only notice it with the fastest moving things like some fast flying birds. The image quality would show a tiny drop in detail but not anything that I would notice in the final image. Overall it was a good way to get to 560mm of focal length and still have f5.6 aperture available 🙂

@@grantatkinson8108 thank you for the response Grant. I think I’ll go ahead and get the TC as it sounds like a good pairing. Are you still using the 400 DO II ?

HI Anand, unfortunately I am not, i traded it for RF gear but it was my mistake to get rid of it, as Canon has not offered anything close to what it can do so far!

me too! What lenses are you using?

Glad it was helpful!

Hi John the menu is the Pink Autofocus menu AF 4 and the top level menu is Lens Drive When AF impossible, and the selection after going into that menu item is Continue Focus Search and it should be ON. That will mean the camera will keep trying to drive a lens focus motor back and forth to keep trying to find focus if it becomes deeply out of focus. It is more relevant with long focal length lenses

Thanks Grant !!