Please explain the need for f2.8 zooms

[tomscott]

I think this is where the amateur and pro argument reaches its peak.

If you are a pro, shooting and making money then gear is a tool, any advantage is a plus. The gear pays for itself whereas an amateur may struggle to justify the purchase. Which is fair. But these zooms are there to guarantee results. Similar to ISO 'better being noisy than missing or getting blurry shots' your better having a smaller DOF than missing the shot entirely.

F2.8 lenses are there for those occasions where you cant use flash, or your in a large room where flash just isnt enough. F2.8 has saved me many a time, also if you are shooting slightly wider you can still get sharp results at F2.8 across a frame, at closer distances the DOF seclusion is more apparent, granted softer but it can be used in those 5% scenarios. Also helps the cameras AF.

If you choose F4 then your advantage is F4 thats it. I know for a fact that when shooting say the first dance at a wedding, using F4-5.6 with flash is still hard even at ISO3200.

But on the other hand, using a 24-105mm with a prime can work really well, it depends on the situation and the light. F4 on the 24-105 gives nice results on a FF camera. The zoom just gives you more scope, instead of worrying about changing lenses. As a wedding photographer using two cameras is a good idea, one with a wider lens (zoom or prime) one with a tele.

TBH a 50mm will have you covered for most of the day at a wedding, so is it necessary? No, but it is nice to know you can IF you need too. Using a zoom can make you lazy with a prime you just have to move around more to find the shot. But you could argue you are more likely to loose the shot.

There are many arguments, it depends on how you like to work and your budget.

[bycostello]

basically having a wide aperture available is like a condom
its better to have it and not need it than to need it and not have it

 

[bycostello]

an f2.8 lens will be sharper at f4 where an f4 lens would be sharper at f5.6 or so...  a jag will go 150 mph but at 70 it hums along beautifully if you get the analogy...

[pakosouthpark]

basically having a wide aperture available is like a condom
its better to have it and not need it than to need it and not have it

just brilliant!!

[spinworkxroy]

basically having a wide aperture available is like a condom
its better to have it and not need it than to need it and not have it

I hear it feels better without so does that mean not having an f2.8 lens feels better too?


just brilliant!!

[Maui5150]

My experience has been they are over all:

-- Faster
-- Sharper

I shoot a 2.8 version versus an F/4 version at say 4 or 5.6, I notice better AF and better over all quality on the shots on the 2.8 version.  I think with most zoom lenses, they have most of their issues at the end so a F/4 lens may be fairly equal to the 2.8 at say F/8 or F/11, but more wide open, especially at F/4 the 2.8 has always out performed in my experience. 

In many case, I find the build and over all range of the lens to be better.  This may be subjective, but in a similar example in the 50s, is the 1.2 really that much better than the 1.4 and the 1.8. 

Yeah.  It is.  Granted, it is an L versus non L as well, but I noticed a huge difference stepping up from the 70-200 F/4 to F/2.8, especially in speed.  Some may argue the price, and the F/4 is a solid performer, but when it comes down to it, with almost anything in life, if your desired range is at the edge of a products capability, you are often better off finding the product that slightly to moderately exceeds your need. 

[Studio1930]

One thing that has not been directly mentioned is that a good photographer will envision the amount of DOF he/she wants in a shot and then adjust the aperture to match based on the focal length of the lens, the distance to the subject and the distance from the subject to the background.  As the distance variables change, so must your aperture to keep the same DOF.

My point is that sometimes you might need f/4 and sometimes you might back up and need f/2.8 to get that same DOF.   You can't do that with an f/4 only lens.  With a slower lens (and/or crop body) you will find yourself needing to get closer to your subject to get a narrow DOF which may have you cropping them more than you wanted.  If shallow DOF shot at a distance is not what you want then a slower lens might work but at some point most professionals want that shallow DOF which slower lenses when shot at a distance (for full length for example) may not provide.

Full length shot with shallow DOF:

[Marsu42]

One thing that has not been directly mentioned is that a good photographer will envision the amount of DOF he/she wants in a shot and then adjust the aperture to match based on the focal length of the lens, the distance to the subject and the distance from the subject to the background.  As the distance variables change, so must your aperture to keep the same DOF

Thanks, I didn't think about this point, keeping a consistent dof across the lens zoom capabilty certainly is a plus for a professional appeal.

Also a big thank you to all posters explaining the pro and cons to me w/o any "just get the best" attitude, to summarize my current understanding f2.8 zooms are for

* keeping a constant dof
* pro-looking bokeh
* faster shutter speed for fast motion with zoom
* reserve in available light situations, though as far as noise goes 5d2+f2.8 = 6d+f4
* sharpness because f2.8 lens stopped down > f4 lens wide open
* more reliable af  - though I wonder if this is valid for the 5d2/6d af? Anyone?

All these points make me tend to get a Tamron 24-70 lens for the 6d after all since my lenses don't pay for themselves by pro shooting, I will shoot somewhat stopped down often and 100% crop sharpness is nice to have, but not critical to me... and the plain matter of the fact is that I could get 2 (two) 6d+24-70vc for 1 (one) 5d3+24-70ii :-o

[enice128]

My experience has been they are over all:

-- Faster
-- Sharper

I shoot a 2.8 version versus an F/4 version at say 4 or 5.6, I notice better AF and better over all quality on the shots on the 2.8 version.  I think with most zoom lenses, they have most of their issues at the end so a F/4 lens may be fairly equal to the 2.8 at say F/8 or F/11, but more wide open, especially at F/4 the 2.8 has always out performed in my experience. 

In many case, I find the build and over all range of the lens to be better.  This may be subjective, but in a similar example in the 50s, is the 1.2 really that much better than the 1.4 and the 1.8. 

Yeah.  It is.  Granted, it is an L versus non L as well, but I noticed a huge difference stepping up from the 70-200 F/4 to F/2.8, especially in speed.  Some may argue the price, and the F/4 is a solid performer, but when it comes down to it, with almost anything in life, if your desired range is at the edge of a products capability, you are often better off finding the product that slightly to moderately exceeds your need.

This is my main argument & reason on why I'm actually going today to upgrade to the 16-35II from my 17-40. A 2.8 aperture is so important for me. I do some small weddings, sweet 16s as well as other events using my 17-40 for over a year now but I feel it's not enough. I love using my 50 1.2 & 70-200 2.8 at these events but my 16-35 will now take the 17-40's place as my main lens. U cannot beat the the overall quality of 2.8 & I absolutely love the look of 2.8 with its DOF!

[bdunbar79]

The standard lens requirement for shooting events/weddings seem to be a combination of 24-70/28 and 70-200/2.8, I read both are nailed to a pro's camera 90% of the time (though I have problems doing the maths :-))

A lens with a larger aperture afaik has three advantages: better af on some bodies, better subject isolation/creativity (just one eye in focus) and last not least a "fast" lens is required for "low light" shots.

My question rose when I read the great book "Captured by the Light" by David Ziser who - believe it or not - writes that f4 to f5.6 (for convenience or added safety) is his bread and butter setting for posed candid wedding flash shots, and he used the 5d2 at that time.

Question: So according to this f2.8 is more important for available light and movement shots, but if that was case with the 5d2, I'm confused why still seems to be still valid with the 6d even though it's about 1 stop better ... either f2.8 was borderline in the past, or f2.8 - 1stop = f4 would be sufficient now - or am I missing something here?

Disclaimer: Please forgive slight traces of irony, this ia a real question because I don't entirely understand the issue, it's great people get whatever gear they like for any purpose they want.

f/2.8 zooms are absolutely essential in low-light situations with fast-moving, or moving subjects.  I don't know of any other pro sports photog who doesn't use an f/2.8 zoom lens.  There are those who argue for primes in indoor sports, but you get less shots and less angles and interesting ones.  I have way more keepers and action with the zoom vs. the prime.  f/2.8 is a whole stop better than f/4 and yes, that makes a HUGE difference.

[Studio1930]

The standard lens requirement for shooting events/weddings seem to be a combination of 24-70/28 and 70-200/2.8, I read both are nailed to a pro's camera 90% of the time (though I have problems doing the maths :-))

A lens with a larger aperture afaik has three advantages: better af on some bodies, better subject isolation/creativity (just one eye in focus) and last not least a "fast" lens is required for "low light" shots.

My question rose when I read the great book "Captured by the Light" by David Ziser who - believe it or not - writes that f4 to f5.6 (for convenience or added safety) is his bread and butter setting for posed candid wedding flash shots, and he used the 5d2 at that time.

Question: So according to this f2.8 is more important for available light and movement shots, but if that was case with the 5d2, I'm confused why still seems to be still valid with the 6d even though it's about 1 stop better ... either f2.8 was borderline in the past, or f2.8 - 1stop = f4 would be sufficient now - or am I missing something here?

Disclaimer: Please forgive slight traces of irony, this ia a real question because I don't entirely understand the issue, it's great people get whatever gear they like for any purpose they want.

There are those who argue for primes in indoor sports, but you get less shots and less angles and interesting ones.  I have way more keepers and action with the zoom vs. the prime.

Sometimes you have such low light that a faster prime like the 200 f/2 or the 135 f/2 is the only way to capture it at acceptable ISO levels.  Also the 200 f/2 focuses faster in low light but this doesn't apply to the original argument about having a constant aperture since it isn't a zoom.

200 f/2 in very low light.

with a 1DX


with a 1D4
Mercury Vapor lights uncorrected:

[TrumpetPower!]

I love it when users say "it's only one stop" when comparing lenses. One stop is a lot! That's twice as good! Some users complain they couldn't tell the difference in rendering from faster glass and then complain that everyone one else can't see the difference.

You keep harping on this "one stop is twice as much," without seeming to realize that, though technically true, there's a very good reason why we use a logarithmic scale for exposure.

In this context, a linear scale is useless. One stop is not, in fact, "twice as good." One stop is basically one zone on the Adams scale. And, while, yes, it's important to place midtones in zone V instead of zone IV or zone VI, it's not exactly a huge deal to move exposures around by a single stop.

By the time you get to two stops, things change. The difference between zone III and zone V or zone V and zone VII is the difference between midtones and shadows or highlights with good detail. But just a single stop? That's your wiggle room, what you have to work with for interpretation, your margin for error.

Cheers,

b&

[bdunbar79]

Studio,

I don't disagree with you at all.  I'm shooting in a gym tonight that I can't use f/2.8, I have to use f/2 or f/2.2 to keep it at 1/500, ISO 5000.  So I have to use the 135L.  Better to have legs cut off vs. no photo at all .

[The_Arsonist]

I love it when users say "it's only one stop" when comparing lenses. One stop is a lot! That's twice as good! Some users complain they couldn't tell the difference in rendering from faster glass and then complain that everyone one else can't see the difference.

You keep harping on this "one stop is twice as much," without seeming to realize that, though technically true, there's a very good reason why we use a logarithmic scale for exposure.

In this context, a linear scale is useless. One stop is not, in fact, "twice as good." One stop is basically one zone on the Adams scale. And, while, yes, it's important to place midtones in zone V instead of zone IV or zone VI, it's not exactly a huge deal to move exposures around by a single stop.

By the time you get to two stops, things change. The difference between zone III and zone V or zone V and zone VII is the difference between midtones and shadows or highlights with good detail. But just a single stop? That's your wiggle room, what you have to work with for interpretation, your margin for error.

Cheers,

b&

Ah, but what if you have to under expose to get the shutter speed fast enough for indoor sports. If one stop is the adjustment curve, and I have to under expose by one stop to get the shot, then there's my wiggle room. I need a 2.8 to get within one stop of my final exposure for indoor basketball. I also use primes, but to get the right moment when someone is driving down the court toward me, I need the zoom.

[Studio1930]

Studio,

I don't disagree with you at all.  I'm shooting in a gym tonight that I can't use f/2.8, I have to use f/2 or f/2.2 to keep it at 1/500, ISO 5000.  So I have to use the 135L.  Better to have legs cut off vs. no photo at all .

Yep, I thought you would since I have seen what you shoot and know you often need faster glass that a zoom can't provide.   I thought I would mention it so others would see that there are times that you just need a faster prime (even though we have diverged from the main point a bit).

As to the poster above (TrumpetPower!) about the 1 stop and the zone info..  1 stop is 1 stop.  You aren't going to shoot an image that has all of its info in just one zone so someplace in your image is probably going to be all of the zones which mean you are going to see the difference from zone 3 to zone 4.  Maybe you personally don't see the difference in 1 stop, but I would argue that most people can take an average image and click one more stop of exposure and see the difference quite well.

Here is one stop of exposure difference...