400mm f/4 DO IS opinions?

[HDNitehawk]

It has been years since I debated this choice. I would arrive at the same decision.
Instead of the 400mm DO get the Version I of the 300mm f/2.8 L.
With the extenders on it will fair as well if not better than the DO.
Without the extenders it is still an excellent lens.
There are multiple copies around 2K on ebay.

[Fast Glass]

So I just realized looking at the ISO crops that there are 1.4x and 2x extender results for the first sample of the lens, facepalm. It is interesting to see there was not as big a difference as I feared between the 300mm f/2.8 IS and 400mm f/4.0 as I thought. The results were mixed and I am still mulling through them, both lenses lost and won in the sharpness department. Contrast was also very very similar to both based on the charts. Of course real life probably will play out differently.

I am giving both lenses significant thought and definitely the 300mm is not ruled out and both are 50/50 right now in my mind, kinda depends on what focal length range I want at this point. 300mm at 420mm loses out slightly to the 400mm across the board except the vertical lines are slightly sharper in the corners on the 420mm results vs the 400mm bare has slightly better horizontal sharpness. Contrast is pretty much the same at comparable focal lengths. Surprisingly they were both nearly the same bare as well.

It is a similar situation with the 560mm vs 600mm comparison with the 400mm being very close to the 300mm. Center is better for the 400, mid frame looses a tiny bit, corners are mixed bag with the horizontal lines sharper on the 300mm and the vertical lines sharper on the 400mm.

Really this is not at all what I was expecting and the 400mm is very very good sharpness and contrast wise, definitely not what I have been hearing. Not to throw anyone under the bus. I'm actually quite happy about this.

So with that said, anyone that actually used this lens that might be able to comment on it's real world sharpness and contrast ect? Since at least in theory there is not that much difference.

Otherwise, I may have answered my own question. LOL, but it still helps to get others opinions.

[Kayaker72]

Hi Fast Glass....

I'd be tempted too for $2,150.

You may have already seen these, but:

• Art Morris did a positive write up on V1. Good comments section.
• Ari Hazeghi's write up on the V2 model has a couple paragraphs of impressions on V1 and a comparison of V2 of the 400 DO vs 300 f/2.8.

Overall, in my mind at least, this would not be a discussion as to whether or not this is a good or bad lens. It is almost certainly a good lens. It is more a discussion of this lens in comparison to everything else that is out there (400 f/5.6, 300 f/2.8, 100-400 v2, etc), what best fits your needs, and then also making sure there is not an issue with this particular copy.

[Joel Eade]

The Canon 300 f/2.8 was the first telephoto lens I bought. Fabulous image quality but I soon found that it never seemed to have enough focal length even for my backyard setup. Sure you can add teleconverters but I suspect (for birding) you would be happier with the 400mm DO which gives an extra 100mm of reach and I suspect is lighter and easier to handle.

[HDNitehawk]

I owned the version 1 and it is a great lens. Another way you might to think of this is that all of your suggestions with convertors are compromises to get length.
Where the 400mm DO is an ok 400mm it isn't one of the great 400mm.
Where in contrast the 300mm f/2.8 is one of the best 300mm that was made.

[Fast Glass]

It is a compromise to get length indeed, but I'm heavily leaning for the 400mm simply because it is longer with it being lighter and shorter as a very nice bonus/strong point.

Having 800mm on the 1D III or 1Ds III cropped to the same amount of reach puts me at the 1000mm range. That is some seriously solid reach for such small light weight package! Mount a high resolution 1.6 crop body for more insane reach if I wanted to.

Technically I could stack extenders, but that probably be relegated to landscape or static subjects if I would even bother. But I would think the IQ would be terrible at that point. V.2 handles it very well though shockingly. But I would still try it for giggles at least once. Lol.