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Old Oct 9, 2006, 10:53 PM   #11
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If you go the DSLR route, expect to pay much more for a fast lens than you will pay for the camera body. Fast lenses are NOT cheap.
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Old Oct 9, 2006, 11:00 PM   #12
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The guy shooting for the newspaper probably used a brighter lens.

It all depends on the lighting how bright of a lens you'll need (along with desired print sizes, percentage of keepers you find acceptable, etc.).

In some of the low light clubs around here, I have to deliberately underexpose ISO 3200 just to get shutter speeds up to around 1/20 second shooting wide open at f/2 with a 100mm f/2. The candles on the tables are the stage lighting. lol

But, in better lighting, I can get much faster shutter speeds.

I had it on 4. From what I recall it hovered in the meter around 125 or thereabouts.
f/4 is not very bright as lenses go. He probably used a much brighter prime (or even a bright zoom with f/2.8 available).

A higher quality zoom will get you f/2.8 througout the focal range. But, that means a larger, heavier and more expensive lens, too.

With a zoom capable of maintaining f/2.8 throughout it's focal range, you could have gotten shutter speeds twice as fast (f/2.8 is twice as bright as f/4). With an f/2 prime, you would have gotten shutter speeds 4 times as fast at ISO 1600 in the same lighting. With an f/1.4 prime, you could have shot at shutter speeds 8 times as fast in the same lighting.

But, most lenses are not quite as sharp at wide open apertures either. Depth of Field will also be shallower at wider apertures (especially on the longer end of a zoom if you're trying to isolate one person with tighter framing). So, keep those things in mind when lens shopping.

I took some snapshots using a cheap ($79.95 new in the box) Vivitar 70-210mm f/2.8-4 lens at f/4 and ISO 1600 Saturday night at a Mother's Finest Concert.

My shutter speeds were running around 1/125 second at f/4 and ISO 1600 on average. Sometimes the light was better, sometimes, worse (they varied the stage lighting quite a bit during the concert and the light was very different between areas of the stage, depending on the performer they had more lights on).

At 1/125 second, you can expect to get some motion blur. But, that's really a pretty good speed compared to some of the lower light clubs around here. lol

If I had known I'd be able to get as close to the stage, I would have grabbed a brighter prime instead though (I've got a 28mm f/2, 50mm f/1.7, 100mm f/2 and 135mm f/2.8 that would all have been brighter than the zoom I was using).

You'll see a touch of motion blur in some of the images I took with this lens at ISO 1600 and f/4 (especially the ones where shutter speeds were down around 1/100 second).


But, sometimes a bit of motion blur can create unusual effects, too. For example, the blur in the hair in this one shot at ISO 1600, 1/125 second and f/4 (and you'll see that many of the photos I took had a bit of motion blur at that shutter speed).

If you want to get rid of more of it, you need a brighter lens shooting in similar lighting at ISO 1600 (but, then, you'll sacrifice some depth of field, too, since it's shallower at wider apertures). So, there are tradeoffs.

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Old Oct 9, 2006, 11:29 PM   #13
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My question still is - how do you tell a fast lens from a not-so-fast one (without relying on the guy trying to sell you one)?
The largest available apertures (represented by smaller f/stop numbers) are printed on the front of the lens with most lenses, and are also shown in the lens specs.

But, you have to take each lens on a case by case basis to see how well it's going to perform at a given aperture setting. Most lenses are sharpest about 2 or 3 stops down from wide open apertures.

Aperture when expressed as f/stop is a ratio between the focal length of the lens and the area of the iris opening diameter.

With a prime (non zoom) lens, you will see one aperture listed.

With a zoom lens, you usually see two apertures listed (the largest available aperture at wide angle zoom setting, and the largest available aperture at the full telephoto zoom position).

When in between the widest and longest focal length of the lens, the largest available aperture will fall somewhere in between the apertures shown in the specs (and printed on the lens).

Some higher quality zoom lenses can maintain a constant aperture throughout their zoom range (with f/2.8 being the most common).

But, most lose some brightness as more optical zoom is used. Some of the cheaper zooms may drop down to an aperture of around f/5.6 on their long end (an f/3.5-5.6 lens is relatively common).

When you vary the aperture, you're controlling the iris in the lens (which like a pupil in your eye, can be opened up to let in more light or closed down to let less light in). Larger available apertures require a lens to be larger for a given focal length, too.

So, lens brightness (largest available aperture) impacts the shutter speeds you'll need for proper exposure (since more or less light is getting through to the sensor). Hence, the term "fast" (as in faster shutter speeds) for a lens that's brighter (larger available apertures, represented by smaller f/stop numbers).

The aperture scale in one stop increments (with larger than f/1 apertures theoritically available) goes f/1.0, f/1.4, f/2.0, f/2.8, f/4.0, f/5.6, f/8.0, f/11, f/16, f/22... With each one stop move to a smaller aperture (represented by higher f/stop numbers), you will need shutter speeds twice as long for proper exposure for the same lighting and ISO speed.

Take a look at this handy calculator to give you an idea of the relationship between light levels, aperture, ISO speed (shown as film speed in the calculator) and shutter speed.


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Old Oct 10, 2006, 6:20 AM   #14
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KM 7D with IS on

28-100mm 'kit' lens @ 100mm

ISO-400, spot metered

1/60 sec, f5.6

Last edited by bernabeu; Jun 27, 2015 at 4:24 PM.
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Old Oct 10, 2006, 6:43 AM   #15
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To add another dSLR on the list:


The Pentax K100D

The Pentax IST DS (Not worse than the DS2 model)

The Pentax IST DS2

The Nikon D50

The Nikon D70s

The SAMSUNG GX-1S (Same as the IST DS2 model from Pentax)

All those dSLRs above have one of the best ISO performances IMO!!

EDIT: Sorry, I must have missed out the Pentax and Samsung "L" models!
The Pentax *ist D is also very good;


noise levels are extraordinarily low, even at ISO 1600.


The K.M. 7D is also not bad.

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Old Oct 10, 2006, 8:52 AM   #16
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I heard back from the photographer who took that picture above.

He is a photographer for a local newspaper, the Martinsville Bulletin.

"OK here's the scoop. First getting a light reading in the auditorium. When you're sitting in the audience, point you camera toward the stage and take a light reading, the camera's meter will give you a false reading. WhY?All that black with a small area also with a black background with the subject lit with a spotlight. If you have it you can use a spotmeter or take a guess. The reason the camera gives you a false reading is the meter is built to turn everything to a light grey. To do that it must add light to the dark room, hence overexposing the subject under the spotlight. Take your reading and stop down about 3 stops.If your meter says shoot at 1/30 sec at f2.8 at ISO 800 try 1/125 at f2.8.How I shot the picture you saw in the paperCamera Nikon D2h (digital SLR)Lens : an old Tamron 300mm 2.8 manual focus lensISO : 1600white balance Incandescantexposure: 1/200 sec at f2.8This is a Nikon digital camera. I have a 1.5 magnifier because the capture area is smaller than the standard 35mm negative area. So the 300mm f2.8 lens shoots like a 450mm f 2.8 lens. I was standing in the back of the room shooting on stage. The advantage of the digital, is I can look at what I shoot and make adjustments. You need at least a 2.8 lens, to do inside available light work, the smaller cheaper telephoto lenses that open up to f 4 or f5.6 are way too slow for low light work. "

Mine is an f4 lens.

I had made some pictures years before at a show with Eric Clapton, from about the same vantage point, using the exact same camera, the exact same lens, the exact same film, and they came out pretty well. However, the main difference in those two shows is how the subject was lit. Stage lighting was all that was different in between those two. The Clapton show was well lit, and in some cases, the light was above & behind him as well as being above & in front, while the Sam Bush show was subject to only the stage lighting.

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Old Oct 10, 2006, 10:01 AM   #17
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Interesting. I didn't realise the jump from say f4 to f.2.8 would make such a huge difference to available shutter speeds.
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Old Oct 10, 2006, 10:07 AM   #18
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MrPogo wrote:
Interesting. I didn't realised the jump from say f4 to f.2.8 would make such a huge difference to available shutter speeds.
f/2.8 is exactly twice as bright as f/4, allowing shutter speeds twice as fast for the same lighting and ISO speed.

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Old Oct 10, 2006, 10:08 AM   #19
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Yes, the problem isn't your camera body, it's the lens. For concerts you need something fast, or a bit of luck.

Although I would recommend you a DSLR still. At concerts you'll make a lot of photos, of which maybe 1/10th are good ones. That's 9/10th of wasted film and precious dollars.

A one time investment in a DSLR and a fast lens will earn back that money very easily. (considering printing is less expensive than developing too)

You'll also have more post-processing options.

I shoot with a Pentax *ist DL, and I'm pretty pleased with it. I don't have a fast lens yet, but I am picking up a SMC-A 50mm f1.7 this thursday

Here's what I managed with the kit lens & a Tokina f4-5.6 telezoom:


Keep in mind that these are selections out of about 100 photos and almost all of them are "lucky strikes"...
A fast lens will improve the odds of getting a good shot.

This is a very interesting part of photography, which I like a lot, I'm sure you'll have loads of fun with it

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Old Oct 10, 2006, 10:09 AM   #20
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schatham wrote:
As far as manufacturers go, which ones as a rule are generally better quality/better performing lenses?
I've been reading around about this lately, seems like people generally think that the better Pentax lenses are as good as Nikon's and Canon's without being nearly as expensive.

Something like the Pentax DA 70 mm F2.4 Limited (medium telephoto, maybe not enough) which is made particularly for digital.

The smc P-FA 85mm F1.4 (IF)is the only (somewhat) telephoto Pentax lens I see with really low F (wide apeture) which will let in a lot more light than typical lenses.

They do offer some longer telephoto/zoom lenses at F2.8.
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