topic Re: Wanting more zoom... in EF & RF Lenses

Wanting more zoom...

inkjunkie — Tue, 05 Dec 2017 17:48:09 GMT

I have an EF 70-200 f/2.8L lens that will be on a 5D Mark IV body. I realize the I can use this lens with either of the Extenders, the version II if I remember correctly. Have read that this will choke back the Aperture some. One of the things I will be doing with my gear is taking pictures at the local race track, many times at night. The track does have lights but last year when I was using one of my old lenses with an aperture of f/5.6 the pictures were far from stellar. Hoping to find a 300mm, or longer, in the f/2.8 area. Does such a lens even exist? Thanks to our ISP pretty much shutting down at 4p.m. not having much luck searching.
Thanks in advance for any help

Re: Wanting more zoom...

kvbarkley — Tue, 05 Dec 2017 18:27:32 GMT

Canon makes both a 300mm/F2.8 and a 400mm/F2.8, but they ain't cheap.

Re: Wanting more zoom...

ebiggs1 — Tue, 05 Dec 2017 20:08:37 GMT

If you bought the ef 70-200mm f2.8L you are not afraid of high prices. But how about talking $10 grand? Does that scare you? Yeah that's right a ef 400mm f2.8L lens is in the ten grand price range.

However, owning a 5D Mk IV you have the ability of higher ISO's that are pretty darn good and very usable. Check out either of the Sigma or Tamron super zooms in 150-600mm range.

In the Canon line there is the ef 400mm f5.6L prime that I really like and it is affordable for anyone. I consider it a must have lens. It doesn't have IS so if that is a factor, it's not to me but it is to some folks, the ef 300mm f4L has IS and handles the 1.4 tel-con very well. Resulting in a 420mm f5.6L lens with IS. By itself the ef 300mm f4L is a great lens and a reasonably fast f4 aperture.

Re: Wanting more zoom...

Hippo69 — Tue, 05 Dec 2017 23:39:01 GMT

I am new to the hobby and have a Rebel T-6. Is the new Tamron 180400 lens compatable with my camera and will it work with my auto settings ? We are going on a trip to Australia next year and I didn't want to take a lot of lens. I am still learing the camera so the Auto settings really are a blessing.

Re: Wanting more zoom...

ScottyP — Wed, 06 Dec 2017 05:30:52 GMT

My friend has the previous version of the Canon 300mm f/2.8 lens and I am always amazed by the shots he gets with it. Beautiful big white lens.

Re: Wanting more zoom...

shadowsports — Wed, 06 Dec 2017 15:16:56 GMT

@Hippo69 wrote:
I am new to the hobby and have a Rebel T-6. Is the new Tamron 180400 lens compatable with my camera and will it work with my auto settings ? We are going on a trip to Australia next year and I didn't want to take a lot of lens. I am still learing the camera so the Auto settings really are a blessing.

Greetings,

You sort of inserted yourself into someone else's thread. Better not to highjack so that your question receives the visibility it deserves. The Tamron lens you selected is a good general (all purpose) wide-zoom. If your goal is to take only one lens, it will allow you to capture good memories of your trip. It's not going to be tack sharp at the max focal length, but will offer good overall performance under varied shooting conditions. Since the T6 has a flash, you'll be able to take pictures in low light up to 10ft reasonably. The lens wil offer you decent reach in the 200-400mm range and decent wide angle perfomanace for landscapes 18-50.

So if you are looking for this type of validation, you have it, The lens will work with your camera. Before buying I would visit DPReview, Youtube, etc, and see what others say about the performance of the lens.

Re: Wanting more zoom...

Hippo69 — Wed, 06 Dec 2017 16:34:30 GMT

Thanks. Sorry I got into someone else's comments. This is the first time I used this site. I am an amature and just so they are decent photos , that is fine with me. Thanks for the reply.

Re: Wanting more zoom...

ebiggs1 — Wed, 06 Dec 2017 16:45:56 GMT

" I am an amature and just so they are decent photos ..."

Canon makes the EF-S 18-200mm f/3.5-5.6 IS Lens. It is made especially for your camera. It is probably a better idea to stay with Canon at this point. The Tamron might work just fine but why risk it when you have this real deal Canon choice?

Did you get the standard kit lens with your Rebel? Of course you did, so the EF-S 55-250mm f/4-5.6 IS STM is a even better choice. Keep your Canon, Canon if possible.

Re: Wanting more zoom...

Hippo69 — Wed, 06 Dec 2017 16:51:10 GMT

Thanks for the advice.

Re: Wanting more zoom...

TCampbell — Thu, 07 Dec 2017 01:52:00 GMT

I own the original EF 300mm f/2.8L IS USM (which wasn't cheap... but that was around $4k) but the current version II is now more like $6k. The 400mm f/2.8 is basically $10k.

After the 70-200mm f/2.8 zoom... the only two f/2.8 lenses are those primes (300 & 400) and everything else is a zoom with f/4 or a variable f/4.5-5.6... so you loose a stop or two of light (and also they cost more.)

You can push the ISO pretty high on the 5D IV (which is what i would do) and you can still clean up the noise with decent software.

Re: Wanting more zoom...

inkjunkie — Wed, 13 Dec 2017 14:34:22 GMT

Sorry for the delayed response. If I wasn't on disability the price tag of that lens wouldn't scare me off...but I would have to wait until I was in one of my bi-polar shopping spree moods...lol...

Having been looking at the 1.4 II extender, wish it didn't take a full stop out as I will be doing a lot of lower light shooting.

Hmmm....

Re: Wanting more zoom...

TCampbell — Wed, 13 Dec 2017 14:54:44 GMT

@inkjunkie wrote:

Having been looking at the 1.4 II extender, wish it didn't take a full stop out as I will be doing a lot of lower light shooting.
Hmmm....

That's really just math. Also the choice of "1.4" has mathematical significance.

The focal ratio of any lens is simply the focal length of the lens (in millimeters) divided by the clear aperture (in millimeters).

So if you had a 100mm lens and it's widest possible aperture opening was 25mm then that would be an "f/4" lens because 100 ÷ 25 = 4.

If you then add a 1.4x tele-converter, it multiplies the focal length by 1.4x... so the 100mm lens effectively becomes a 140mm lens.

However... the 100mm still only has a 25mm aperture opening... the tele-converter can make the focal lenght longer, but it can't make the lens physically wider. So now when you divide 140mm (the new effective focal length) by the 25mm aperture opening (because that part didn't change) you get 140 ÷ 25 = 5.6.

Notice how the lens dropped from an f/4 to an f/5.6 (which is exactly one full f-stop) by adding a 1.4x extender. That only happens because the multiplier is 1.4.

It turns out 1.4 (the real value is 1.41421...) is the square root of 2. Whenever you change the size of a circle by the square root of 2 (either multiply the diameter by the square root of 2 to make it larger ... or divide the diameter by the square root of 2 to make it smaller) you will EXACTLY double or halve the area of that circle.

And since this particular circle is the aperture opening which allows the light to flow through the lens, you exactly double or halve the amount of light that can arrive at the sensor (assuming the shutter speed wasn't changed).

So the 1.4x multiplier was selected because it happens to be the square root of 2 (well... a rounded off value for the square root of 2) and it changes the exposure by exactly one full f-stop so you don't have to worry about fractional f-stop changes.

A 2x change to a circle's diameter will quadruple it's area (if making it bigger) or reduce it to one quarter (if making it smaller). So a 2x extender changes the camera's effective f-stop by 2 full stops.

Basically you muliply BOTH the focal length and the focal ratio by the multiplier of the tele-converter.

This is true of all teleconverters.

Re: Wanting more zoom...

ebiggs1 — Wed, 13 Dec 2017 14:55:30 GMT

"Having been looking at the 1.4 II extender, ...."

The 1.4 tel-con works with the 70-200mm f2.8 but it doesn't work with all of Canon's lenses. So be careful there if you have another tele or zoom in mind.

Re: Wanting more zoom...

RobertTheFat — Wed, 13 Dec 2017 15:30:29 GMT

inkjunkie wrote:
Sorry for the delayed response. If I wasn't on disability the price tag of that lens wouldn't scare me off...but I would have to wait until I was in one of my bi-polar shopping spree moods...lol...
Having been looking at the 1.4 II extender, wish it didn't take a full stop out as I will be doing a lot of lower light shooting.
Hmmm....

Yes, the extender turns an f/2.8 lens into an f/4. But you mainly need f/2.8 indoors, and you mainly need the extender outdoors. So it sort of works out.