Canon RF 100-300 f/2.8 IS USM

[Kayaker72]

Resolution is a funny thing in that if you do not have a subject with detail that requires that level of resolution then the additional resolution is simply not needed.

Looking at Bryan't test, the 100-300 @ 300 mm does look better than with a 2x TC @ 600 mm. Yet, the way Bryan does his test, the 600 mm test result was 2x further away. Looking at his specs, he actually used the same distance but a chart that was half the size. So, equivalent to 2x further away.

So, for 2x more "reach" I am actually impressed with the performance of the 2x TC.

Looking at your comparisons, I like the contrast the best with the naked lens, but I am seeing details/texture in the steps and the shaded sides of the step that I do not think I can see with the naked lens. That said, I think it would be easier to assess details in a subject like a bird, a pine tree's needles or something else with a lot of fine detail.

[Busted Knuckles]

Thanks for the double checks. The focus point was at the front if the steps/lower hand railing. Is there the depth of field issue re the mens room sign.

I sent both back. I was thinking of doing the optimal f stop (7.1) but seems like the difference was so small that fiddling with the 2x seems wonky.

[neuroanatomist]

Looking at his specs, he actually used the same distance but a chart that was half the size. So, equivalent to 2x further away.

The QA-77 chart comes in 4 sizes, the smaller ones are useful for long lenses. I have about 60 feet line-of-sight where I do my testing, and that's means using one of the two smaller sizes with lenses over 400mm.

[Kayaker72]

I believe at least 3 forum members own this lens.

What do you use it for? Which lenses has it replaced?

With price increases likely to hit Canon soon, I am contemplating the RF 100-300 f/2.8. I have been holding out for the 200-500 f/4 (hopefully with built in TC). But, put a 1.4x TC on this lens, and it is 140 to 420 f/4. Essentially what I was looking for. Some images and test charts I've seen make it seem like it takes the 2x TC very well. Among the problems that exist with coveting gear that doesn't actually exist, I am concerned about the likely price point of the 200-500 f/4. $15,000? With tariffs, $17,000???

Which brings me back to the 100-300 f/2.8 at $9,500 (before adjusted for tariffs). With 1 lens and 2 TCs, I could have a 100-600 lens from f/2.8 to f/5.6. This is something I could find very useful, especially for large animal photography. I have looked over my images from Yellowstone a few years ago, and my wildlife images were typically with the 24-70 II on my 5DIV (at the time) or M6II with the 500 II. But this may sum up my recent photography. I am photography birds and need a lot of focal length (granted 600 mm is pretty good) or landscapes/cityscapes and I am in the general purpose range. So I seem to have either needed virtually no focal length or all the focal length I can get. Add in that recent videos I've watched of people on Safari and the 100-300 f/2.8 seems to be the lens that did not leave their camera bodies, it seems to have become the go-to lens for large animal safaris.

So, I am thinking of giving up on the 200-500 f/4 for now and picking up the 100-300 f/2.8. I am just trying to wrap my head around how often I would use it and if I would be better off renting it from time to time (at ~$700 for a 2 week rental).

Any thoughts and/or experiences to share?

[neuroanatomist]

I use the bare lens mainly for indoor events (concerts and other performances), and I use it with the 1.4x mainly for field sports. It does take the 2x TC well, though I don't use that combo much. After getting the 100-300/2.8, I find that I am using the RF 70-200/2.8 much less. The 100-300 is a great pairing with the 24-105/2.8 for both indoor and outdoor events/sports.

I do suspect that the price of the 200-500/4 will be in the $14-15K range, not considering tariffs (because who knows if or what those will be, if/when the lens launches).

For me, even with the 2x TC the 100-300 is on the short side for birds (where I'm usually at 840mm f/5.6). But for large animals, with the TCs that would be the ideal range.

Rumor is that prices will be going up 7-8% very soon (next week, apparently), and for a $9500 lens that's basically the cost of a week's rental.

Mainly, I think it comes down to your use cases and the frequency at which you'd use it. I used a 70-200/2.8 extensively for events for years (EF MkII then RF), mostly my kids' performances. As they moved into middle school and high school, the venues got bigger and I was finding that 200mm wasn't long enough. But since that was post-RF, the 300/2.8 II was hard to get (not impossible), and even availability aside I was reluctant to spend that much on an EF lens. I was waiting for an RF 300/2.8, and was not thrilled with the size of the 100-300/2.8 relative to the EF prime but the flexibility of a zoom is more than worth the tradeoff. In terms of frequency, since getting the lens I've taken 22% of my saved images with it.

[Busted Knuckles]

Kayaker - your question was exactly mine. I tested the 1.4 and the 2.0 on the 100-300. I did some pixel peeping and was perhaps overly harsh. The 100-300 is nuts sharp on its own at 2.8. As I have the R5 using 1/2 the pixels (thinkng the old OM 1/2 frame) at 24 mp seemed like an adequate response to looking for 'reach' beyond the 300. Thought having said this, I am going to give the 2x another try in the coming weeks.

As far as real world - I haven't had much time to shoot with it. I saw the rumor on the 200-500. If it has the same IQ as the 100-300 that would be a real head scratcher for me.

My questin is more of a how do a put in a bag and take it on a plane - the 100-300 is pretty darn large and the tripod coller doesn't come off (though I did replace the foot w/ a arca model - why canon doesn't machine these is a bit of PITA)

[neuroanatomist]

My questin is more of a how do a put in a bag and take it on a plane - the 100-300 is pretty darn large and the tripod coller doesn't come off (though I did replace the foot w/ a arca model - why canon doesn't machine these is a bit of PITA)

Based on comparison of the 100-300/2.8 to the EF 300/2.8 II, it is likely that an RF 200-500/4 would end up being about the size of the RF 600/4. That will fit in a carryon case (without a camera attached).

[Jonathan Huyer]

I'm loving the 100-300 f/2.8, and I use it a lot with the 1.4 TC attached. It has a long enough reach for owls, but of course it's inadequate for smaller birds. I'll be using it as my main lens for photographing bears on a trip this summer, and I probably won't even need the converter for that. But if I do, I'll still have the wide end covered with the 70-200 f/2.8 on a second body. The 100-300 is easy to hand-hold, which is a big plus. I don't own the 2x TC and I'm pretty sure I never will. The lens really shined on my trip to Brazil last year, where I was photographing wildlife in very dim light. The f/2.8 aperture saved the day (see below). All in all I'm very happy with it! But if/when the mythical 200-500 f/4 comes out, I'll sure be tempted

[Kayaker72]

Thanks everyone. Much appreciated.

I've seen the rumor that the price hike will only be in the 7-8% range, which isn't really enough to force a decision. Yet, what I am concerned about is that it could increase and be in the 15-25% range in the not so distant future.

You all have convinced me, the 100-300 f/2.8 could easily be a foundational lens in my kit. My primary use would be larger wildlife. My problem....I have nothing planned in 2025 where I am photographing larger wildlife. 2026, maybe. But as I have thought about picking up the 100-300 f/2.8, I think about getting excited and then not having an immediate use for it. I do not have kids in concerts or in sports. My remaining vacations in 2025 are out to Idaho and over to Italy (another vacation tacked onto a work trip). Banff is still up in the air, but if our NA Manager goes there, I'll likely not make it. But right now I am mostly shooting eagles, osprey, backyard birds, landscapes, and other general travel type photography. Even portraits has dropped way off for me with the ages of my family.

For local stuff, I am well covered.

Maybe I could add a weekend trip or two up north to try to photograph moose. That tends to be in the evening.

[Busted Knuckles]

I am going Friday a.m. to do some bird pics at the Orlando Wetlands park, 1st thing a.m. and will have the 2x with me for the 100-300 and will post the 'real world' images from that trip over the weekend.

I am getting a roller/backpack type case (Vanguard VEO SELECT 55T Trolley) as my current back isn't thick enough and it is a bit dated/used up as well.

Also picked up the R5II for kicks and giggles and will be posting side by sides w/ the R5 Mk1. Don't expect massive differences, but will see.

Stay tuned.

Mike