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11-02-2010, 12:57 PM   #16
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QuoteOriginally posted by Lowell Goudge Quote
I tested an XR Rikenon 135/2.8 side by side against an SMC Yakumar 135/3.5
Japaneze gangsters have taken over the lens industry? The Yakuzas produce Yakumars? Oh, the humanity...

11-02-2010, 05:20 PM   #17
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WTF: With crazy ISO noise control and image stabilization in both bodies and lenses, who really cares if a lens is F1:1.4 or F1:4. Throw in several noise reduction programs and the issue is both moot and muted. Cheers. Don A.
11-02-2010, 05:56 PM   #18
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QuoteOriginally posted by donallison13 Quote
WTF: With crazy ISO noise control and image stabilization in both bodies and lenses, who really cares if a lens is F1:1.4 or F1:4. Throw in several noise reduction programs and the issue is both moot and muted. Cheers. Don A.
Except that image stabilization can't freeze subjects and small apertures can't give shallow depth of field for creative control
11-02-2010, 07:15 PM   #19
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QuoteOriginally posted by donallison13 Quote
WTF: With crazy ISO noise control and image stabilization in both bodies and lenses, who really cares if a lens is F1:1.4 or F1:4.
Y'know, I thought that to myself today as I wandered around Carson Pass (Calif. Sierras Nevada, SW of Lake Tahoe) with my Sears-Tomioka 55/1.4 on my K20D, and I had to stop down to f/8-11 to cut the sunlight at 8900 feet. So I swapped it for my Macro-Takumar 50/4 (1:1) and proceeded. But when the sun disappeared behind the peaks around Kirkwood, I had to go for the Sears/1.4 again.

1.4 vs 4.0? In some situations, no matter. In other situations, great matter, for the reasons Lowell listed. When light's not a problem and/or thin DOF doesn't matter and/or you use a tripod and/or your subject is sedated, a slow lens is fine. Otherwise, not.

Don't mistake me. Some of my favorite glass is slow. (Not like the science fiction SLOW GLASS; that's another subject.) From a Meyer Primagon 35/4.5 and Helioplan 40/4.5 and Telemegor 180/5.5, to the MacTak 50/4 and Schacht Albinar 135/4.5 and Tele-Takumar 200/5.6 and Alpa-Chinon 300/5.6 (and not forgetting the mighty Industar-50/3.5), they do wonders. But I don't take those lenses into dark alleys. Wouldn't be prudent, at this juncture. Not without a tripod.

11-03-2010, 02:55 AM   #20
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QuoteOriginally posted by RioRico Quote
Y'know, I thought that to myself today as I wandered around Carson Pass (Calif. Sierras Nevada, SW of Lake Tahoe) with my Sears-Tomioka 55/1.4 on my K20D, and I had to stop down to f/8-11 to cut the sunlight at 8900 feet. So I swapped it for my Macro-Takumar 50/4 (1:1) and proceeded. But when the sun disappeared behind the peaks around Kirkwood, I had to go for the Sears/1.4 again.

1.4 vs 4.0? In some situations, no matter. In other situations, great matter, for the reasons Lowell listed. When light's not a problem and/or thin DOF doesn't matter and/or you use a tripod and/or your subject is sedated, a slow lens is fine. Otherwise, not.

Don't mistake me. Some of my favorite glass is slow. (Not like the science fiction SLOW GLASS; that's another subject.) From a Meyer Primagon 35/4.5 and Helioplan 40/4.5 and Telemegor 180/5.5, to the MacTak 50/4 and Schacht Albinar 135/4.5 and Tele-Takumar 200/5.6 and Alpa-Chinon 300/5.6 (and not forgetting the mighty Industar-50/3.5), they do wonders. But I don't take those lenses into dark alleys. Wouldn't be prudent, at this juncture. Not without a tripod.
I think some of the point is that if you are going to always shoot at the sharpest aperture of any lens, typically that is around F8 so in that respect it does not matter, but if you want narrower DOF, LOw Light, or even just a brighter view finder, fast is better. Also, when considering focusing, fast glass is more accurate to focus because with slower lenses DOF makes focusing to the exact correct point difficult.
11-03-2010, 01:17 PM   #21
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Once plenoptic handheld cameras come out all this fstop stuff will become moot. All you'll need to do is select a focus point like an eye or eyes. Or you could select the eyes of a couple. Then you select the forground and background you want. You tell the
11-03-2010, 01:22 PM   #22
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AI what kind of old fashioned f1.2 Canon 85mm L you want to emulate and the angle you were at. With the fake light sources. Etc just like 3D Studio Max or Maiya or Lightwave. You'll all be out of a job with how easy it'll be.

11-03-2010, 01:51 PM   #23
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QuoteOriginally posted by brofkand Quote
How many lenses can you point out that are just as sharp wide open as they are at all other apertures?

I don't know about you, but virtually every lens I've seen is softer / less contrast / etc wide open. Whether or not it's a huge difference is one thing, but it is there. It's measurable, like a cup of sugar.

So "sweet spot is a myth" is in and of itself a myth.

I would rather shoot at ISO 100 at f/1.4 than I would at ISO 800 at f/5.6

There may not be much noise at ISO 800, but that noise went somewhere. It wasn't never there; the camera removed it. And it's very likely that in the process it removed some detail that I would have had, had I shot at ISO 100.

High ISO is such a load of baloney. I can shoot at ISO one million, but if there is no detail there what's it mean? I see photos shot at ISO 6400 all the time, people say they're gorgeous. I say yeah, but why can't I count the number of eyelashes the subject has?

I would get more resolution out of instamatic film!

It amazes me the "trends" in photography....Pictorialism, HDR, toy cameras, high ISO, etc etc.
To me, this is the best and most accurate analysis of the subject, although I still think HDR is way too cool when properly done.

I currently do HDR shitily, and am working my way up to crapily.
11-03-2010, 02:23 PM   #24
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Ira,
What I don't like about HDR is the multiple frames. You need at most 11 for a realistic pic which means any movement from a living scene doesn't work. For my best work I use tiffs processed in photomatix.
11-04-2010, 10:02 PM   #25
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QuoteOriginally posted by reeftool Quote
A slightly slower lens is cheaper to manufacture and will probably sell more. This debate is raging on in various threads about the new DA35/2.4. Why not f/2 or faster? How many people would buy one at 3 times the price? The camera manufacturers are running a business. They have to make a profit and balance the fine line of price vs. quality. If a lens ends up being too expensive, very few will buy it.
You defeated your own argument here given the FA 35/2 was $299 shipped when it was discontinued.

QuoteOriginally posted by donallison13 Quote
WTF: With crazy ISO noise control and image stabilization in both bodies and lenses, who really cares if a lens is F1:1.4 or F1:4. Throw in several noise reduction programs and the issue is both moot and muted. Cheers. Don A.
Noise reduction programs aren't the end all. The better the image you start with, the better the end result. Polish a turd, it is still a turd.

Last edited by Blue; 11-04-2010 at 10:09 PM.
11-04-2010, 10:06 PM   #26
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QuoteOriginally posted by Ash Quote
Cameras bumping ISO up secretly? I'm not so sure. My Tamron 70-200 is optically quite a complex lens. I shoot with it at f/2.8 and 4 often at ISO 1600 on my K20D. Results from these shots show no sign of them being any noisier than any other ISO 1600 shot I've gotten from a simpler FA 50 or 77.

Not a believer.
That's the point I make when the subject comes up. I can still shoot at ISO 1600 whether I'm using the FA 50/1.4 or A 50/1.2. In low light, the bigger aperture helps with metering and focusing as well, especially when mf is required in part or completely.
11-05-2010, 05:50 AM   #27
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I think there are a whole lot of opinions here being expressed, based upon different points of view, but not really consistent with the issue at hand

First and foremost, After doing testing using the same lens on 3 different cameras, there is no significantly obvious loss of sensor performance at large apertures.

regardless of camera type and sensor technology, the biggest change I see is more than likely due to the fact that the lenses are simply not true at maximum aperture, and / or there are variations in the accuracy of the aperture.

What is suprising is that, all cameras are so close in performance as a function of aperture.

Also note that this issue was supposed to be a predominantly C Moss issue, yet the K7 actually appears to be better than the CCD sensors in the K10 and *istD, which is the inverse of the published paper.

so, point 1, bumping ISO for fast lenses is a myth, there is no sensor related issue requiring it. (Note that 2 of the 3 sensors that I tested are also used in sony and nikon cameras , therefore if pentax does not need it why should the others?)

Point 2) no matter how you slice it, software cannot replicate correctly depth of field, you cannot immitate shallow DOF with software or the bokeh of different lenses, if people want narrow DOF they need fast lenses

point 3) while there may be noise at high ISO, regardless of NR programs, chips themselves are getting better. the high ISO gains in current cameras are not all software, there are hardware gains at the base of high ISO. so the noise hasn't magically gone somewhere, electronics manufacturers have improved processes and designs to reduce the noise at the source.

point 4) while in theory, slower apertures "cost less" because there is less glass involved, that is in reality pure BS. the cost of optical elements is going and lenses as a total, is laregely dependant on process, and production runs. Sure if you are going to make 1 copy of an F1.4 lens for every 100 copies of the F2.4 lens, yes the F1.4 will cost more, BUT, if you are going to make 100 copies of the F1.4 lens for every 1 copy of the F2.4 lens, the F2.4 lens will cost more, because production runs are smaller, development costs amprtised into the lens are more heavily loaded, machine setup and non recurring costs are more in teh production phase, and inventory costs are higher because you will be stocking parts longer, or finished product longer. where you win is picking the most desireable spot, and getting price vs quantity correct.

with the 35F2.4, pentax may have missed the mark, when you consider sigma and samyang doing faster 35mm lenses. and here is the risk. what if no one buys the 35F2.4 because it is not what they want.

I think marketing got it wrong.
11-05-2010, 10:28 AM   #28
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We will see. I predict the DA 35 2.4 will sell fantastically. Shallow DOF creative work is a niche market - most good photographs are not abstracts and flowers. Most people want high quality sharp images of people and places at a reasonable cost. Very few photographers are good enough to shoot good pictures of a person at f 1.4. Most prefer the look of f 2.8. The people who want those low DOF shots can pay the premium, I'm sure Pentax would prefer to sell a cheap lens to many people, who do not care that it is "slower" than the bulky sigma prime for 2X the cost.

I agree with the contention that lenses should be marked with T-stops. Most lenses I have tried let in different levels of light at equivalent f-stops. For me, the f-stop is less about DOF, and more about getting the light in. Occasionally I'll use one of my 50's to blur the background but the fact is my two 50's let in different levels of light at equivalent f-stops! It's a dated way of measuring lens performance and I think it's going to need to change if the primary format has moved from film to 1's and 0's.
11-05-2010, 11:03 AM   #29
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QuoteOriginally posted by paperbag846 Quote
We will see. I predict the DA 35 2.4 will sell fantastically. Shallow DOF creative work is a niche market - most good photographs are not abstracts and flowers.
what about low light, at 1.5 stops slower than the sigma 35mm, that is a much darker viewfinder at night, regardless of shooting aperture.
QuoteQuote:
Most people want high quality sharp images of people and places at a reasonable cost. Very few photographers are good enough to shoot good pictures of a person at f 1.4. Most prefer the look of f 2.8.
but that was with 50-85mm lenses on film, what does F2.8 give you with a 35mm lens , about 4 times the Depth of field
QuoteQuote:
The people who want those low DOF shots can pay the premium, I'm sure Pentax would prefer to sell a cheap lens to many people, who do not care that it is "slower" than the bulky sigma prime for 2X the cost.
that is where the argument will be. I am not so sure that an F1.4 /35mm needs to be any bulkier. look at the simple math Fstop = focal length / aperture diameter. F1.4 on 35mm is a 25mm diameter element, this is already very small compared to the diameter of the lens mount, which to some extent determines the lens dimensions. The bulk will be in the packaging not the glass.
QuoteQuote:
I agree with the contention that lenses should be marked with T-stops. Most lenses I have tried let in different levels of light at equivalent f-stops. For me, the f-stop is less about DOF, and more about getting the light in. Occasionally I'll use one of my 50's to blur the background but the fact is my two 50's let in different levels of light at equivalent f-stops! It's a dated way of measuring lens performance and I think it's going to need to change if the primary format has moved from film to 1's and 0's.
but you don't need T-Stops unless you are going to do away with internal metering, and, by the way, digital has much more exposure lattitude than slide film, where F stops were found to be acceptable, so why go back to something painful to measure.

T-Stops are only of need when you do not have an internal light meter, that is why they disappeared they were no longer needed.
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