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01-22-2019, 08:29 AM   #61
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QuoteOriginally posted by Fogel70 Quote
The last couple of years it seems like the trend is long heavy lenses are getting lighter, and short light lenses are getting heavier.

Latest Canon super teles have lost a lot of weight in the latest version.
600/4 IS from 3920g to 3050g.
400/2.8 IS from 3850g to 2820g

50/1.2 from 580g to 950g
Doesn't Fresnel lens design help the most with telephoto lenses? This seems to be what Nikon and Canon are doing with their telephotos. Maybe in the long run every lens in our bags will be between 900 and 2000 grams regardless of the focal length.

01-22-2019, 08:54 AM   #62
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Horses for courses.
It is a little strange to see these very large, very wide aperture lenses, as it seems to me the real use case for them is pretty limited. Astrophotography clearly benefits from very sharp, very wide lenses, but that's a pretty narrow use case and limited market.
Beyond that, I'm not sure how many people really need lenses that provide both paper-thin depth of field and edge to edge sharpness. Not sure how many people really need the upcoming Nikon 0.95 Noct Z lens.

On the other hand, some of this is more sophisticated in lens focusing. Faster, quieter, more accurate. There are, it seems to me, a fair number of use cases for that. Sports, wildlife, wedding. The 55-300 PLM lens is great on that front. Enough so that I use that and my KP frequently instead of my K-1 and 70-200. The weight penalty isn't worth the IQ gains. But my understanding is that the PLM tech doesn't scale up to heavier glass. i.e., you couldn't use that on the 150-450, or probably not on a f4 600.
01-23-2019, 08:12 AM - 1 Like   #63
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QuoteOriginally posted by SteveinSLC Quote
Beyond that, I'm not sure how many people really need lenses that provide both paper-thin depth of field and edge to edge sharpness. Not sure how many people really need the upcoming Nikon 0.95 Noct Z lens.
I agree. It's simply another example of human irrationality. Over the years, I've run across photographers who were absolutely obsessed with fast apertures. This obsession, as far as I could make out, seemed to arise from a fairly widespread photography disease known as tripodphobia. In short, they want to take hand held shots in very low light, and they believe that fast aperture is the way to do it. They think that at f 0.95 they can finally shoot that black cat in a coal mine without using flash and/or a tripod. Little do they think that at f 0.95, they're only going to be able to get one of the cat's eyes in focus, so that rest of the across the frame sharpness wide open provided by the lens will be lost.
01-23-2019, 09:27 AM   #64
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One reason why I still use APS-C as prime system is because I prefer light lenses. So all those DA Limited lenses are like custom designed for me.
Mirrorless FF is my secondary system mainly for (compact) vintage lenses.

IMO todays camera system has become like distasteful fashion. Kind of like the 80s which where way over the top in ugliness.
Or maybe I'm just starting to get too old.

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01-24-2019, 12:29 AM   #65
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In the past Canon made a 0.95 objective for their rangefinder camera. It was an awful objective, unsharp and with a bad light transmission. I have seen the same issue with my m42 50mm 1.4 Super Multi Coated Takumar objective no 5446137, the last version. At 1,4 it gives the same lightamount as SMC 50 mm 1.8, measured with Spotmatic and Ricoh Single.
I know that today coating is very advanced, but all other topics equal, more lenses in an objective gives less transmission. Is this fundamental problem solved today?
I hope that my english is good enough to explain a technical matter

---------- Post added 01-24-19 at 12:31 AM ----------

getting older is not the same as getting too old
01-24-2019, 01:28 AM   #66
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QuoteOriginally posted by niels hansen Quote
In the past Canon made a 0.95 objective for their rangefinder camera. It was an awful objective, unsharp and with a bad light transmission. I have seen the same issue with my m42 50mm 1.4 Super Multi Coated Takumar objective no 5446137, the last version. At 1,4 it gives the same lightamount as SMC 50 mm 1.8, measured with Spotmatic and Ricoh Single.
I know that today coating is very advanced, but all other topics equal, more lenses in an objective gives less transmission. Is this fundamental problem solved today?
I hope that my english is good enough to explain a technical matter

---------- Post added 01-24-19 at 12:31 AM ----------

getting older is not the same as getting too old
If you are asking about T stops, I don't know how effective modern lens designs are vs designs with fewer elements but poorer coatings and lens materials that are less advanced.
01-24-2019, 01:40 AM   #67
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Whether we like it or not a lot of us are getting older and WEAKER so no matter what comes out it will feel too heavy and or large, I rarely touch my 70-200 now because of weight and size, pity as it is a great lens, HAHA gotta buy some dumbbells, Ian

01-24-2019, 01:47 AM   #68
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QuoteOriginally posted by UncleVanya Quote
If you are asking about T stops, I don't know how effective modern lens designs are vs designs with fewer elements but poorer coatings and lens materials that are less advanced.
Otto Croy writes in Das Contax Buch that just after ww2 many Contax owners got their prewar objectives coated with the result that Zeiss objectives became better than the comparative Leicas. That shows the importance of coating.
The question is: Will a first class objective with a moderate f value have a better transmission than an ultrafast?
01-24-2019, 02:02 AM   #69
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QuoteOriginally posted by niels hansen Quote
.
The question is: Will a first class objective with a moderate f value have a better transmission than an ultrafast?
That's a question I'm interested in as well.
01-24-2019, 04:22 AM   #70
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QuoteOriginally posted by UncleVanya Quote
If you are asking about T stops, I don't know how effective modern lens designs are vs designs with fewer elements but poorer coatings and lens materials that are less advanced.
To me, the biggest thing that modern coatings have done is to improve flare resistance and to maintain contrast in a variety of situations. I know that they do help light transmission some, but I would think in situations that do not involve shooting into a strong light source, the difference would be minimal.
01-24-2019, 07:57 AM   #71
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QuoteOriginally posted by Rondec Quote
To me, the biggest thing that modern coatings have done is to improve flare resistance and to maintain contrast in a variety of situations. I know that they do help light transmission some, but I would think in situations that do not involve shooting into a strong light source, the difference would be minimal.
If I remember correctly transmission rate on old SMC coating was 99.8% and the latest coatings reflect half as much, so they are 99.9%.
So in a lens with 20 lens elements the total loss would be 8% with SMC coating, and with HD coating it is 4%. The change from 92% to 96% in transmission in all lens elements is not something you will easily notice, but twice as much reflections may be quite noticeable in some situations.
01-24-2019, 09:26 AM   #72
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QuoteOriginally posted by Fogel70 Quote
If I remember correctly transmission rate on old SMC coating was 99.8% and the latest coatings reflect half as much, so they are 99.9%.
So in a lens with 20 lens elements the total loss would be 8% with SMC coating, and with HD coating it is 4%. The change from 92% to 96% in transmission in all lens elements is not something you will easily notice, but twice as much reflections may be quite noticeable in some situations.
T values are irrelevant on through the lens systems, because light is measured after the light has passed thought the lens and an 8% drop in light won't change your exposure settings.
01-24-2019, 10:06 AM   #73
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QuoteOriginally posted by normhead Quote
T values are irrelevant on through the lens systems, because light is measured after the light has passed thought the lens and an 8% drop in light won't change your exposure settings.
It is quite relevant when interested in the amount of light transmitted and how this compares across lenses - but you are right in that TTL metering means that there is no direct impact to exposure accuracy. But if a simpler design at f/1.8 gathers the same or more light as a very complex f1.4 design the resulting exposure could favor the f/1.8 lens in low light over the f/1.4 - this is the question the OP is asking. It is largely academic I think as the T number delta's I have seen the past for primes are very very small even for complex designs.
01-24-2019, 10:34 AM   #74
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QuoteOriginally posted by UncleVanya Quote
But if a simpler design at f/1.8 gathers the same or more light as a very complex f1.4 design the resulting exposure could favor the f/1.8 lens in low light over the f/1.4 - this is the question the OP is asking
As you say it could.... but what are the odds?
My guess is, next to zero. Modern sensors have at least a half stop latitude when determining correct exposures. First, for that to be true, you'd have to establish that in your ideal test circumstances where theoretically it could make a difference, there would be a discernible difference in photo quality. Until that is done, it's just speculation. It' pretty pointless discussion the theoretical importance of various lens attributes when no real world differences have been reported. Common practice says it's irrelevant. I'm going with that until shown a circumstance where it isn't. Then we'll have something we can analyze.

First establish that something happens. Then determine how often it happens. Then you have a result you can trumpet form the roof tops. Often, the theoretical difference makes no practical difference. I also don't accept the idea that an extra chocolate chip will in any meaningful way affect the taste of my chocolate chip cookies.

Back when I was a department head, part of my responsibility as i saw it was telling new teachers which parts of the education act they could safely ignore. If you followed everything down to the letter, that was a sure recipe for a mental meltdown. Sometimes, knowing what to ignore is as important as knowing what to do.

What are T-values for you ask? IN the motion picture industry, it is necessary to maintain exact exposure values for different pieces of film that may be spliced together at some point. Exact values are needed because of the need to create the illusion of continuity. And most movie cameras are not TTL metering. T values are of interest to filmmakers and perhaps photographers using hand held light meters. They do have a purpose, but for the most part, it's not still DSLR photography.

Last edited by normhead; 01-24-2019 at 11:32 AM.
01-24-2019, 03:04 PM   #75
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Because I know absolutely nothing about digital camera gear, I can't speak to what is considered acceptable or heavy or light. Perhaps heavy digital photography gear will spur an interest in film cameras and lenses again? Is there a difference between the two? I can say that with film equipment (Spotmatic, two or three Auto-Takumar wide and normal primes, maybe a reasonable telephoto if needed, filters, etc.), it's all pretty light. I have found bulk to more of an issue than weight (I like a small backpack). That said, with all the talk about too much weight and then some talk of goats, maybe we need more pack goats (better than mules)... they're a real thing.
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