Sigma 120-300 focal length at closest focus distance ?

[Mike Neary]

So I heard that the Sigma 120-300 2.8 DG HSM loses some focal length at closer distance... That sounds quite normal, since all IF zooms have this "feature". But how bad is it ? Take a look at the specs below:

min. focus distance magnification

Sigma 120-300 DG HSM: 4.9ft / 1.49m 1:8.6
Nikon 300 f/4 AF-S: 4.8ft / 1.46m 1:3.7
Nikon 70-200 AF-S VR: 5ft / 1.53m 1:6.1

These lenses all have similar min. focus distance, but their magnification ratios are wildly different. Actually, they are pretty consistent for the 2 Nikkors since the 300 is about 1.5x better than the 70-200 VR for magnification, which is what you would expect. But 1:8.6 for the 120-300 ??? That would indicate that the actual focal length at that distance drops something less than about 150mm!!!

I am currently considering whether the 120-300 2.8 would make an upgrade for my 300 f/4 AF-S, because of the extra f-stop and zoom feature... But what I need most for birding is reach, and the 120-300 seems to lose a lot of that as the subject distance decreases

Looks like the 120-300 would be more of a "sideways" move compared to the 300 f/4... So maybe I need to just be happy with my 300 f/4 and start saving for the 200-400 f/4 VR

Anyone have any experience with both, and how much loss of focal length typically occurs with the Sigma in practice ?

Cheers

Mike

 

[gmosc]

Very interesting idea Mike, but what looks like a bummer for you, can in a weird way work as an advantage for me....

You see, I've been considering the sigma 50-150 to replace my ailing (unrepairable) Nikon 80-200 f2.8 for indoor club/theater pictures. My recent honest appraisal of my own shots proved to myself that the 150-200mm range on the Nikon were sort of vanity shots that only proved that I could get the musician's face but said so little of what was going on on stage musically (no sign of an instrument in sight!).

I've resigned myself to realize that the 50-150 could work well including getting a little more person in the pictures at 50mm.

If the 120-300 loses so much range because of IF, does that mean that at close range it would almost act like a true 70-150mm?! In which case, when I stepped outside it would then become more of the 300mm that it is rated at? In this way, it sort of becomes a wider ranged lens like 70-300mm!?

I slightly dread the 50-150 because I would love to have a little more reach for outside shots even though it should be perfect indoors. This 120-300 lens looks a little interesting.... hmmmm......

Guy Moscoso

 

[gmosc]

OK,

2289 dollars... that would be... let's see......11,664 Danish kroner....hmmm that's a little out of my range....... but... hmmmm I don't know..... sure is something to think about!

Guy Moscoso

 

[Mike Neary]

Very interesting idea Mike, but what looks like a bummer for you, can
in a weird way work as an advantage for me....
You see, I've been considering the sigma 50-150 to replace my ailing
(unrepairable) Nikon 80-200 f2.8 for indoor club/theater pictures. My
recent honest appraisal of my own shots proved to myself that the
150-200mm range on the Nikon were sort of vanity shots that only
proved that I could get the musician's face but said so little of
what was going on on stage musically (no sign of an instrument in
sight!).
I've resigned myself to realize that the 50-150 could work well
including getting a little more person in the pictures at 50mm.

Sounds like the 50-150 is actually the lens you want - light & small, and covering the right focal range.

If the 120-300 loses so much range because of IF, does that mean that
at close range it would almost act like a true 70-150mm?! In which
case, when I stepped outside it would then become more of the 300mm
that it is rated at? In this way, it sort of becomes a wider ranged
lens like 70-300mm!?

Hmm. I would think you would raise some eyebrows with the big 120-300 at an indoor event

The big gun is definitely not handholdable, you need a monopod at the very least!

I'd like to know what the progression is for the 120-300 focal lengths... If it's 150mm at closest distance, and 300mm at infinity, what is it at, say, 5m/15ft ?
That's a distance I'm often shooting at if a bird or small animal gets close.

I slightly dread the 50-150 because I would love to have a little
more reach for outside shots even though it should be perfect
indoors. This 120-300 lens looks a little interesting.... hmmmm......

But the 120-300 costs $2600 here in the U.S.! For that money, you can get a 50-150 for indoors and a 70-200 VR for outdoors, and still have some cash left over for a TC-17E II...

The 70-200 VR may actually work even better for concerts due to its unique combination of f/2.8 and VR. You can get handheld shots at 1/60 at 200mm, no problem at all!

Cheers

Mike

Guy Moscoso

 

[gmosc]

Mike,

You are right. I should just get the 50-150 and be done with it. I got 300mm covered in the cheap 70-300 and 70-300ED lenses which I should just use and be happy with. My 300mm shots aren't my most important shots .

But, this info you have pointed out will also be the case with the 50-150 making it a less than 50-150 but ,maybe a 45-135 at close range, which maybe wouldn't hurt me either. It could keep me from zooming in too close.

Guy Moscoso

 

[Mike Neary]

Mike,
You are right. I should just get the 50-150 and be done with it. I
got 300mm covered in the cheap 70-300 and 70-300ED lenses which I
should just use and be happy with. My 300mm shots aren't my most
important shots .

The cheapest way to improve your 200-300mm shots is with the 70-300 VR!
My wife uses it (and I occasionally grab it if the 70-200 VR + TC is too bulky).

Hardly any difference in IQ between the 70-300 VR and the 70-200 VR + TC-17 (the 70-200 VR + TC-14 is slightly better).

But, this info you have pointed out will also be the case with the
50-150 making it a less than 50-150 but ,maybe a 45-135 at close
range, which maybe wouldn't hurt me either. It could keep me from
zooming in too close.

Looks like the 50-150 does not suffer too dramatically from the shortening of focal length: min focus distance 3.6ft/1m, magnification 1:5.3. The 55-200 VR also focuses close to 1m, and has 1:4 magnification, but also 33% more focal length.

The most dramatic focal length shortening I've noticed so far was with the 18-200 VR, which shortens to less than 100mm at min. focus distance. Looks like the Sigma 120-300 is similar in that respect!

Cheers

Mike

 

[Lasse Eisele]

I could be wrong on this, but I believe the 120-300 has a variable minimum focus distance. It only focuses down to 2.5 m at the long end. It still loses some focal length at closer distance but not nearly as much as you thought. I've never used the lens though, so take this with a grain of salt.

Regards
Lasse

So I heard that the Sigma 120-300 2.8 DG HSM loses some focal length
at closer distance... That sounds quite normal, since all IF zooms
have this "feature". But how bad is it ? Take a look at the specs
below:

min. focus distance magnification

Sigma 120-300 DG HSM: 4.9ft / 1.49m 1:8.6
Nikon 300 f/4 AF-S: 4.8ft / 1.46m 1:3.7
Nikon 70-200 AF-S VR: 5ft / 1.53m 1:6.1

These lenses all have similar min. focus distance, but their
magnification ratios are wildly different. Actually, they are pretty
consistent for the 2 Nikkors since the 300 is about 1.5x better than
the 70-200 VR for magnification, which is what you would expect. But
1:8.6 for the 120-300 ??? That would indicate that the actual focal
length at that distance drops something less than about 150mm!!!

I am currently considering whether the 120-300 2.8 would make an
upgrade for my 300 f/4 AF-S, because of the extra f-stop and zoom
feature... But what I need most for birding is reach, and the 120-300
seems to lose a lot of that as the subject distance decreases

Looks like the 120-300 would be more of a "sideways" move compared to
the 300 f/4... So maybe I need to just be happy with my 300 f/4 and
start saving for the 200-400 f/4 VR

Anyone have any experience with both, and how much loss of focal
length typically occurs with the Sigma in practice ?

Cheers

Mike

 

[K.C.Chan]

I think you mentioned birds.

The data you mentioned is true. But I still think that 120-300mm is very good for small birds if you add a 2xTC.

As you said that reach is the main thing we need for birds. 300mm is far from enough for me and I will miss a lot of shots just because the bird is out of range.

With a 2xTC, 600mm, this improved my successful rate a lot.

Not the best results, but acceptable for me.

I would recomand it for bird if you add a 2xTC, and do not want to pay for a Nikkor 600mm.

Seeing them better than hearing what I say. Good luck.

(Almost all taken at 600mm, Sigma 120-300 with 2xTC. With D70 or D2X.)

More in my gallery.















http://www.pbase.com/nikond70/image/40894036,jpg





--
Kin

http://www.pbase.com/nikond70

 

[K.C.Chan]

Both at 600mm by D2X, Sigma 120-300, 2xTC





--
Kin

http://www.pbase.com/nikond70

 

[Mike Neary]

I think you mentioned birds.

Yes, that's what I use my 300 f/4 for.

The data you mentioned is true. But I still think that 120-300mm is
very good for small birds if you add a 2xTC.

But if my data is correct, then the 120-300 with 2x TC would only be about 300mm at minimum focus distance, not 600mm!

I mostly use my 300 f/4 with the 1.4 and 1.7 TC, and that means 420mm and 500mm reach at the same minimum focus distance. Seems like the lens I have gets me more reach already

As you said that reach is the main thing we need for birds. 300mm is
far from enough for me and I will miss a lot of shots just because
the bird is out of range.

Yes, of course. I always use a TC with my 300 f/4.

With a 2xTC, 600mm, this improved my successful rate a lot.

Not the best results, but acceptable for me.

Nice pictures, thanks for posting! Looks like the 120-300 takes the 2x TC quite well.

I would recomand it for bird if you add a 2xTC, and do not want to
pay for a Nikkor 600mm.

That was what I was thinking, but now I believe the 500mm I already have is actually longer than the 600mm of the Sigma at most practical bird shooting distances - as strange as that may sound

Cheers

Mike

 

[Lasse Eisele]

But if my data is correct, then the 120-300 with 2x TC would only be
about 300mm at minimum focus distance, not 600mm!

I tried to tell you that your data is not correct. If you don't believe me, have a look at Sigma's own data:
http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3274&navigator=3

Minimum Focusing Distance is 150-250 cm (which means 250 at the long end). You won't lose much focal length.

But don't expect stellar performance with a 2X TC. It would be wiser to save for a Sigma 500/4.5 if you can't afford a Nikkor.

 

[Mike Neary]

But if my data is correct, then the 120-300 with 2x TC would only be
about 300mm at minimum focus distance, not 600mm!

I tried to tell you that your data is not correct. If you don't
believe me, have a look at Sigma's own data:
http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3274&navigator=3

Minimum Focusing Distance is 150-250 cm (which means 250 at the long
end). You won't lose much focal length.

Ah, thanks - I see what you mean now! Yes, that sounds much better - except I would lose the close focus of 1.5m for the 300 f/4. It seems that the focal length loss may only be something like 25% then. Still, that would mean focal length at minimum distance is only about 225mm, right ?

But don't expect stellar performance with a 2X TC. It would be wiser
to save for a Sigma 500/4.5 if you can't afford a Nikkor.

Yes, or the 200-400 VR... It'll be a while

Cheers

Mike

 

[Lasse Eisele]

But if my data is correct, then the 120-300 with 2x TC would only be
about 300mm at minimum focus distance, not 600mm!

I tried to tell you that your data is not correct. If you don't
believe me, have a look at Sigma's own data:
http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3274&navigator=3

Minimum Focusing Distance is 150-250 cm (which means 250 at the long
end). You won't lose much focal length.

Ah, thanks - I see what you mean now! Yes, that sounds much better -
except I would lose the close focus of 1.5m for the 300 f/4. It seems
that the focal length loss may only be something like 25% then.
Still, that would mean focal length at minimum distance is only about
225mm, right ?

It's way past bedtime here and my brain is a bit fuzzy by now. You may be right but hopefully the lens won't lose that much focal length.

But don't expect stellar performance with a 2X TC. It would be wiser
to save for a Sigma 500/4.5 if you can't afford a Nikkor.

Yes, or the 200-400 VR... It'll be a while

Hehe, I have the cash to buy that lens. It's the divorce I can't afford.

 

[K.C.Chan]

Hi Mike,

You may be right if the bird land at the minimum focal distance. If it is, 300mm will be enough.

However, the bird usually land quite further away from the minimum focal distance. Even at 600mm, most of my photo need a lot of crop.

I think I will use my old 70-300ED at 300mm focal length to compare with 120-300mm at a very short focal distance to see if there is big differences. Not only for you, actually you make me want to find out now.

Will post when I got the results.
--
Kin

http://www.pbase.com/nikond70

 

[K.C.Chan]

Hi Mike,

You may be right if the bird land at the minimum focal distance. If
it is, 300mm will be enough.

However, the bird usually land quite further away from the minimum
focal distance. Even at 600mm, most of my photo need a lot of crop.

I think I will use my old 70-300ED at 300mm focal length to compare
with 120-300mm at a very short focal distance to see if there is big
differences. Not only for you, actually you make me want to find out
now.

Will post when I got the results.
--
Kin

http://www.pbase.com/nikond70

--
Kin

http://www.pbase.com/nikond70

 

[Jersh]

Mike, I did just the opposite of you... I started off with the 120-300mm f2.8 and then sold it in favor of the Nikon 300mm f4 AF-S and 1.7x TC. I use(d) both of them primarily for birds and therefore was zoomed to 300mm 99% of the time so I don't miss the zoom at all (except when I'm at a sporting event). One major drawback to the Sigma lens is the lack of a focus limiter switch. If you've become accustomed to using this feature on your Nikon lens you will definately miss this on the Sigma. It's not really a problem if you are photographing stationary objects, but the second you try to focus on a bird in flight or something else moving fast, you will notice it (especially if the subject moves off of the AF sensor and you must go through the entire focal range before you reacquire). In my experience, that results in A LOT of missed opportunities.

You are correct, when you are near the minimum focus distance, the maximum focal length is more like 270mm if I recall.

 

[Mike Neary]

Mike, I did just the opposite of you... I started off with the
120-300mm f2.8 and then sold it in favor of the Nikon 300mm f4 AF-S
and 1.7x TC. I use(d) both of them primarily for birds and therefore
was zoomed to 300mm 99% of the time so I don't miss the zoom at all
(except when I'm at a sporting event). One major drawback to the
Sigma lens is the lack of a focus limiter switch. If you've become
accustomed to using this feature on your Nikon lens you will
definately miss this on the Sigma. It's not really a problem if you
are photographing stationary objects, but the second you try to focus
on a bird in flight or something else moving fast, you will notice it
(especially if the subject moves off of the AF sensor and you must go
through the entire focal range before you reacquire). In my
experience, that results in A LOT of missed opportunities.

Interesting experience - thanks for the data point! I think I heard that from someone else before, that they ditched the 120-300 for the 300 f/4... But what about the f/2.8 ? Do you not miss that ?

And what about IQ at 500mm with the TC-17 vs the Sigma at 600mm with the 2x TC ? About the same ? I mean, can you crop the 300 f/4 shot to 600mm and get the same resolution ?

Questions, questions...

You are correct, when you are near the minimum focus distance, the
maximum focal length is more like 270mm if I recall.

Not less than 250mm ? That would be my simple calculation based on the magnification at min. focus distance.

Cheers

Mike

 

[Jersh]

IMO the IQ with the 300mm f4 + 1.7x is far and away superior to the IQ of the 120-300mm f2.8 + 2x. I would say the IQ of the 300mm f4 + 1.7x might even be marginally better than the 120-300mm f2.8 + 1.4x. I rarely if ever shot the 120-300mm wide open, mine seemed a little soft at f2.8 so I would stop it down, to f8 when I had a TC on it. Mind you, the 120-300mm f2.8 was my first 'big' lens, prior to that lens my only experience was with a cheap 70-300mm. Therefore my technique was not great and I was using it on a tripod and ballhead (w/ Wimberly Sidekick) that wasn't as robust as I probably needed. Here's a thread from a different forum with more info on the focal length shortcomings of the 120-300mm f2.8

http://www.naturescapes.net/phpBB2/viewtopic.php?t=52847&highlight=sigma+120300mm

 

[Mike Neary]

IMO the IQ with the 300mm f4 + 1.7x is far and away superior to the
IQ of the 120-300mm f2.8 + 2x. I would say the IQ of the 300mm f4 +
1.7x might even be marginally better than the 120-300mm f2.8 + 1.4x.
I rarely if ever shot the 120-300mm wide open, mine seemed a little
soft at f2.8 so I would stop it down, to f8 when I had a TC on it.
Mind you, the 120-300mm f2.8 was my first 'big' lens, prior to that
lens my only experience was with a cheap 70-300mm. Therefore my
technique was not great and I was using it on a tripod and ballhead
(w/ Wimberly Sidekick) that wasn't as robust as I probably needed.
Here's a thread from a different forum with more info on the focal
length shortcomings of the 120-300mm f2.8

http://www.naturescapes.net/phpBB2/viewtopic.php?t=52847&highlight=sigma+120300mm

Very interesting! Thanks for all the info. Looks like that settled it - I'll stick with what I have until I can afford the 200-400 VR (if ever...)! Or maybe a used 300/2.8

Cheers

Mike

 

[jiggins2010]

Ok How have you come up with the answers that the Sigma 120-300 lens has a zoom of around 250 instead of 300mm. Normally i'm pretty good with maths and working things like this out but i'm stumped this time. Is there a formula to get this answer an easy way. Like the max aperture is length of lens / diameter of lens front element (300mm/105mm=f/2.8). Any help in this matter would be much appreciated.

--



:: James David :: http://www.pbase.com/inspired_me ::