• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia

lens advice please (1 Viewer)


Active member
I have a canon 90d body and my biggest lens is a canon 100 to 400 zoom.
In a local nature park their are loads of herons but they are a long way off so i would like to get a bigger lens , the photo shown was taken with the 100 to 400 at its 400 max.

I cant afford to go for the canon 800mm as it is £13,000 so i need somebody to recommend me a large lens and adapter made by another company that will work on my canon body.
Looking at smaller lens on Amazon i get the impression that if you use other makes of lens and adaptors you cant use auto , this wont cause me a problem !


  • 1.JPG
    1.1 MB · Views: 48

Owen Krout

Registered User
First of all, the free alternative: Even hand held, your gear should be good enough for usable ID photos at some really long ranges. The 90D has more pixels to work with than my 7D and I can say from experience that with proper settings you should be able to obtain some very good shots, even up to where you can't ID, or even at times see, the subject with the naked eye. The trick is to use software to process and crop the image. Free software is available for either Microsoft or Apple. I'm no longer familiar with PC, but I suspicion that like Apple it comes equipped with software that will do the job. If not plenty of free options can be had at the App Store. I don't have your original file, but it looks like your settings are probably fine.

Second option is to try the Sigma 150-600mm Contemporary lens. I've used one extensively on Canon gear and it is a great lens for the price. Not quite Canon L series good, but given the cost, it's perfectly fine. The main downside is the weight. One step up from that is the more expensive Sigma 150-600mm Sport lens. I don't have experience with that one though. Either should be readily available as a used lens.

A third option would be that the Canon 1.4 Extender does work with the 90D and the Canon 100-400mm zoom as long as there is good lighting. The camera will struggle a little bit with autofocus and auto exposure but it does work. Lighter weight, but honestly if you really think you need the range, the Sigma is a better choice in my experience.

At 800mm the field of view starts to become so narrow that even finding the target can be a challenge and any shake from hand held or even the wind starts to become a real problem. Personally, I have settled into Canon L lenses in the 400mm range as ideal and then cropping the image.

Chosun Juan

Given to Fly
Australia - Aboriginal
One option a mate of mine has (on his self curs-ed at times 7D II - in comparison to our Nikon D7200's and D500's) is the 300 f2.8L with a 2x TC for 600mm f5.6. The glass itself is superb.

It's ~2.6kg, so heavier than my G2 Tammy 150-600 f6.3 (2kg), but still just lighter than some of the Sigma Sport super zooms, and the image quality is a step up.

If Nikon had a lightweight 300 f2.8FL - that's what I'd be using with the 2x TC.

Actually, what I really want is a 600 f5.6 PF , but Nikon has so far steadfastly refused to make that too .....

Chosun 👩

Barred Wobbler

Well-known member
I've been using the Sigma 150-600 Sport since April 2015, shortly after it came out until just a couple of months ago, when as a response to going mirrorless in December I bit the bullet and splashed out on a Canon RF 100-500. Before that my camera body was the 7DII and it was a great match with the Sigma, giving good results with both perched birds and birds in flight (annual trips to Tarifa for raptor migration, plus other migration trips to various locations in spring until Covid put the kybosh on that). I'd really recommend a Sigma 150-600.

I've not used the Contemporary, only my higher spec Sport, and although people pass comment on the weight, it's a lot lighter than a big Canon and this 70-year-old has been happily using it as a walk-around lens on a shoulder sling, taking maybe up to a thousand and more shots a day in raptor migration season plus much lower numbers but with more miles walked at home for 6 years without complaint until my head was turned by the cleaner (and I admit much lighter) mirrorless combination.

Photos from autumn 2019


  • Honey-Buzzard-(51)-fbook.jpg
    576.5 KB · Views: 47
  • Honey-Buzzard-(247)-fbook.jpg
    436.2 KB · Views: 45
  • Honey-Buzzard-(401)-fbook.jpg
    92.3 KB · Views: 42
  • Honey-Buzzard-(406)-fbook.jpg
    94.4 KB · Views: 44
Last edited:


Well-known member
I would echo the Warlord and add the Tamron 150-600 G2 as an option. Nothing wrong with the Sigma contemporary, it's a good bit cheaper. The second gen Sigma & Tamron are better than the first and results are similar, but as noted the Sigma Sport is much heavier.

Owen Krout

Registered User
In support of Chosun, I didn't mention it as it could be outside of what you want to spend, but my current everyday lens is a Canon 300mm f4 L IS coupled with a 1.4 MK III Extender. It is sharper than the Sigma, lighter weight and I got a good deal on a used lens. Fine, airborne dust is a constant problem in China and being a fixed lens avoids the issue of even the best of telephotos slowly ingesting dust. Plus since I rarely remove it from the body, it keeps the camera body itself sealed. I haven't tried it yet, but have been told by others that it would work well with a 2.0 Extender.

Mark Jarrett

Up Ont’ Moors
There is also the option of sticking with Canon and buying one of their prime lenses second hand, dependent upon what your budget is. A 300mm with a 2x extender or a 500mm with a 1.4. I have used MPB on two or three occasions and found them to be excellent to deal with. The lenses they sell are graded on condition and I have always bought either ‘excellent’ or ‘as new.’ If you want to get rid of your 100-400 (I wouldn’t as it’s a great lens), they will take it in part exchange.


Well-known member
In my opinion those birds are much too far away to get really good images. Sure you can get an image that will enable you to id the bird. But, that is about it. To get good display or printing images you will have to get a LOT closer to the birds.
ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia
ZEISS. Discover the fascinating world of birds, and win a birding trip to Colombia
ZEISS. Discover the fascinating world of birds, and win a birding trip to Colombia

Users who are viewing this thread