[dadipentak]

Today

[TenZ.NL]

Really impressive, Joe and Dadi. I have been neglecting this beauty lately

[Mike.P®]

Does it AF with the 2x TC?

I use the 2x a lot with my 70-200 /2.8 EX (non DG non macro) with great results, always looking for more length

Yes it does but the light has to be perfect otherwise it just hunts.

[nomadkng]

In my initial testing with the 2x, I've gotten 75%? focus lock as long as there's decent to good lighting and some edges.

For example, I had trouble locking on a masonary wall at twilight, but same time could focus on a palm tree trunk

not bad for 600mm. i'm hoping it comes in very handy in Yellowstone in a month

[joe.penn]

How is overall IQ with the 2x? When I use the 1.4 With this lens, the IQ is only descent, when I use the 1.4 with the 300 2 .8 The IQ is excellent.

[dadipentak]

How is overall IQ with the 2x?

I tried it with the 2x the other day but hand-held so not really fair. I'll try to do a better job soon and post some results.

[joe.penn]

Great, thanks dave...

[Lowell Goudge]

How is overall IQ with the 2x? When I use the 1.4 With this lens, the IQ is only descent, when I use the 1.4 with the 300 2 .8 The IQ is excellent.

I tried it with the 2x the other day but hand-held so not really fair. I'll try to do a better job soon and post some results.

I think the use of TCs is highly variable. But consider that the 100-300 F4 was likely not planned to be used with a TC due to the speed, but the 300/2.8 was. Same with the original 70-200/2.8 that I use. I believe it was always planned to be used with TCs and the IQ with a 2x is excellent., in fact the IQ is so good, it is likely why I have never really seriously considered getting a bigger faster lens. Although I keep thinking an extra 2-300 mm would be useful

[dadipentak]

Ok, here are some test results taken with K-5 + Sigma APO EX DG 100-300/4 +Sigma APO EX DG 2x TC on tripod in pretty optimal conditions (very good morning light from behind & no wind.) The first of each pair has been resized to a width of 1000p, the second is a crop to 1000p. No other processing.

[180mm (x2=360mm) 1/640s, f5.6, ISO 640]



[300mm (x2=600mm) 1/640s, f5.6, ISO 200]



[300mm (x2=600mm) 1/640s, f5.6, ISO 250]



With both birds AF was quick and sure but when I tried to focus on the ball away from the "seam", it couldn't find focus (not enough contrast in those little Xes.)

This is a long combination, btw, so a tripod is pretty essential.

Bottom line: it's not what I'd choose for a birding expedition but if I'm traveling someplace where there might be interesting birds (among other subjects) this would be a good, versatile set-up.

[TenZ.NL]

Thanks for the shots and crops, Dave. It seems to get really soft with the 2x TC, especially on the longer distances. In fact that`s the same behavior I obeserved with the 1.4 TC.

How is overall IQ with the 2x? When I use the 1.4 With this lens, the IQ is only descent, when I use the 1.4 with the 300 2 .8 The IQ is excellent.

Exactly my gripe with this combo, the bare lens has great optics but when the 1.4 gets involved it`s bearly decent. So I`m about to pull the trigger on the 300 F2.8 (in part thanks to you)

[dadipentak]

Mind you those samples were shot in RAW and would clean up siubstantially in PP. Still, it's not a combo I'd want to depend on--especially since conditions aren't always so good. What I wanted when I bought the lens was a really good 100-300 zoom and that's what I got. I think you're right that if you're looking for 300 that can deliver high quality IQ with a TC, you'll want a different lens.

[joe.penn]

Ok, here are some test results taken with K-5 + Sigma APO EX DG 100-300/4 +Sigma APO EX DG 2x TC on tripod in pretty optimal conditions

Dave, thanks for posting those. I will be purchasing a 2x DG TC sometime this week and will give it a go on the 300 2.8.

Thanks for the shots and crops, Dave. It seems to get really soft with the 2x TC, especially on the longer distances. In fact that`s the same behavior I obeserved with the 1.4 TC.

Ya, same here, it seems to do the same thing with my combo of this, Another thing I noticed with the combo using the 1.4 TC is the bokeh is kind of, well, horrendous - I am guessing the extra elements in the TC is the reason for this.

So I`m about to pull the trigger on the 300 F2.8 (in part thanks to you)

It is a great lens, my only gripe is the weight of it, I can hand hold it for maybe a minute or so but after that I need a rest. It's hard as I shoot from watercrafts most of the time (kayak and pontoon) and can't really use a support system as most of the time the kayak or pontoon is moving up and down and side to side. When I am in blinds, I do use a shooters bi-pod with a ballhead, the bi-pod setup is great as it allows me to lay on the ground and use it, a really good setup that I can recommend to anyone who shoots wildlife (and even sports) from the ground or even at knee level.

I think @Lowell Goudge is right on though about the use of TC's and different lenses, some lenses just weren't made for TC's or designed with performance in mind when using TC's.

[dadipentak]

think @Lowell Goudge is right on though about the use of TC's and different lenses, some lenses just weren't made for TC's or designed with performance in mind when using TC's.

Yeah, he usually is and I agree this lens was meant to be used as is.

[iittoo]

Use with Sigma 1.4x Apo Ex Dg

[maverickh]