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01-23-2019, 10:44 AM - 4 Likes   #826
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Actually, why don't we stop discussing "equivalency"?

01-23-2019, 11:16 AM   #827
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QuoteOriginally posted by Rondec Quote
Actually, using equivalency, 35mm is better than medium format digital as the lenses are faster at equivalent focal lengths.
could they not make 'faster' lenses???
01-23-2019, 11:20 AM   #828
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QuoteOriginally posted by Kunzite Quote
Actually, why don't we stop discussing "equivalency"?
In case you do not suffer from obsessive-compulsive equivalence disorder, it will probably not be too difficult for you to stop discussing it.
01-23-2019, 11:30 AM   #829
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QuoteOriginally posted by Kunzite Quote
Actually, why don't we stop discussing "equivalency"?
Introducing equivalency talk in a thread plays the same role as a forum moderator: it's so powerful it can make any troll derail from trajectory.

01-23-2019, 11:35 AM - 5 Likes   #830
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QuoteOriginally posted by biz-engineer Quote
Introducing equivalency talk in a thread plays the same role as a forum moderator: it's so powerful it can make any troll derail from trajectory.
It can make everyone derail from relevance to meaningless.
01-23-2019, 06:22 PM - 3 Likes   #831
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QuoteOriginally posted by reh321 Quote
could they not make 'faster' lenses???
Of course they. Optical engineers can make anything*. If Pentax took the new Pentax DFA* 50mm f/1.4 and multiplied all the dimensions by 1.3 and they could put out a nice 65 mm f/1.4 for crop 645. However, the lens would literally weigh twice as much as the DFA* 50 and cost a fortune.

Overall, sensor size has a huge influence on lens size which is one big reason larger format cameras come with much slower lenses.

*Lens makers for astronomy make some insane things. There's a spectrographic camera called Binospec that goes on the MMT (Multiple Mirror Telescope) in Arizona. The camera include two huge lenses to couple the sensor to the telescope. The 19 lens elements in the full system range 8" to 15" in diameter. One of the larger elements is 44 pounds and made of fluorite and the craziest element is a 12" diameter lens made of NaCl (table salt). The entire lens assembly weighs about 800 pounds.
01-23-2019, 07:29 PM - 1 Like   #832
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QuoteOriginally posted by photoptimist Quote
Of course they. Optical engineers can make anything*. If Pentax took the new Pentax DFA* 50mm f/1.4 and multiplied all the dimensions by 1.3 and they could put out a nice 65 mm f/1.4 for crop 645. However, the lens would literally weigh twice as much as the DFA* 50 and cost a fortune.

Overall, sensor size has a huge influence on lens size which is one big reason larger format cameras come with much slower lenses.

*Lens makers for astronomy make some insane things. There's a spectrographic camera called Binospec that goes on the MMT (Multiple Mirror Telescope) in Arizona. The camera include two huge lenses to couple the sensor to the telescope. The 19 lens elements in the full system range 8" to 15" in diameter. One of the larger elements is 44 pounds and made of fluorite and the craziest element is a 12" diameter lens made of NaCl (table salt). The entire lens assembly weighs about 800 pounds.
So ultimately that is the same discussion. MF could gather more light than FF if people were willing to spend enough and lug enough. For some people, either cost or weight makes the appropriate FF lenses 'unavailable', so entire discussion comparing FF to smaller formats is a waste of electrons. People weigh options and then make decisions.
01-23-2019, 09:00 PM   #833
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QuoteOriginally posted by reh321 Quote
So ultimately that is the same discussion. MF could gather more light than FF if people were willing to spend enough and lug enough. For some people, either cost or weight makes the appropriate FF lenses 'unavailable', so entire discussion comparing FF to smaller formats is a waste of electrons. People weigh options and then make decisions.
And with the use of equivalence you can make a more educated decision on what format to choose. As it makes it easier to understand the relation between the existing options.

I'm not sure I understand the importance of not using equivalence?

01-23-2019, 09:16 PM - 3 Likes   #834
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QuoteOriginally posted by Fogel70 Quote
And with the use of equivalence you can make a more educated decision on what format to choose. As it makes it easier to understand the relation between the existing options.

I'm not sure I understand the importance of not using equivalence?
When I first got my Q-7, I discovered that it was better on most interior shots than my aging Canon Rebel was ..... all I had to do was to take a few photos to see that; that was a very educated decision based on actual facts. When I purchased a K-30, I found that there were fewer places where the Q-7 was superior - many of them being a result of the Q-7's size and whisper quiet leaf shutter .... again an educated decision based on actual facts. Now I have a KP, and the Q-7 is getting even less use .... guess what - another educated decision based on observation of actual photos. Without "equivalence" I already know where to look for comparison issues, but there is more than just size of sensor involved in superiority, and there is no way to fit age of design, actual implementation, and similar issues into a mathematical analysis {the 'accelerator' is giving me fantastic results, for example}
01-23-2019, 09:34 PM   #835
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Are you saying you bought Q7, K30 and KP blindly, not knowing anything of the advantages they would bring before you bought them?

What disadvantage would equivalence have given you in these decisions? Equivalency is not a religion so it do not claim to give the answer to all the questions you might have, it is only an additional tool for helping on the relation between formats.

For me in this situation would have ment that would have to by K1 and a number of FF lenses to understand that FF would not bring enough adavantages over APS-C for me.

Last edited by Fogel70; 01-23-2019 at 09:43 PM.
01-23-2019, 11:14 PM - 1 Like   #836
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QuoteOriginally posted by Fogel70 Quote

But for exposure there is no difference between sensor and pixel as they both capture the same amount of "light per unit area" in the same exposure.
You undermined yourself in your post 815, Fogel:

"So at the same exposure a larger sensor captures more light. Which is why a larger sensor tend to give less noise in images at the same ISO as a smaller sensor."

It's about the pixels, not the sensor. They are the capturers of light in a physics formula, not the wafer.

That's why DxOMark measured 9.6dB for the noise test at ISO 51200 for the K-5 IIs, and 9.8db at the same ISO for the K-1.
01-23-2019, 11:16 PM - 1 Like   #837
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QuoteOriginally posted by Fogel70 Quote
Equivalency is not a religion
(Laughs)
01-23-2019, 11:32 PM   #838
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QuoteOriginally posted by clackers Quote
You undermined yourself in your post 815, Fogel:

"So at the same exposure a larger sensor captures more light. Which is why a larger sensor tend to give less noise in images at the same ISO as a smaller sensor."

It's about the pixels, not the sensor. They are the capturers of light in a physics formula, not the wafer.

That's why DxOMark measured 9.6dB for the noise test at ISO 51200 for the K-5 IIs, and 9.8db at the same ISO for the K-1.
No, it is you that still do not get dxomark, or understand the difference between exposure and captured images!

What you see above must be the screen score, which compare noise in a fixed number of pixels. The print score will show a much larger difference as it represents the noise difference in whole images.
01-24-2019, 03:44 AM - 2 Likes   #839
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QuoteOriginally posted by Fogel70 Quote
Are you saying you bought Q7, K30 and KP blindly, not knowing anything of the advantages they would bring before you bought them?

What disadvantage would equivalence have given you in these decisions? Equivalency is not a religion so it do not claim to give the answer to all the questions you might have, it is only an additional tool for helping on the relation between formats.

For me in this situation would have ment that would have to by K1 and a number of FF lenses to understand that FF would not bring enough adavantages over APS-C for me.
My account began in the middle of the adventure. I began with 'box' type cameras in the 1950's, including one that used '620' film; by the time I purchased my first 35mm rangefinder camera in 1969, I already knew that an ability to adjust shutter speed was the most important asset to my developing interest in photographing railroads {and the graduation money I had would cover this camera, but not any MF camera available to me then}. By the time I purchased my first SLR in 1979, I knew that an ability to change lenses was now my way to progress. By 2007, when I was ready to go digital, APS-C was my affordable path forward. Over the next eight years, I learned that an APS camera overall met my needs better than any FF camera {I still had working "FF" film cameras over this time period}. In fact, when @Adam gave away a K-1 last June, I chose to avoid the 'excitement' ; By July, I decided that using the K-1 in crop-mode would "be OK" when using a 55-300mm lens, but it was the "best" path for me only if someone else were purchasing the K-1. In 1976 I had used birthday money to purchase a '110' camera as an experiment, and had established the value to me of a 'pocketable' camera; the Q-7 was just the latest in that sequence. Even though I was a math major, I didn't need arcane calculations to do any of that.

Last edited by reh321; 01-24-2019 at 04:11 AM.
01-24-2019, 04:15 AM - 1 Like   #840
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QuoteOriginally posted by clackers Quote
You undermined yourself in your post 815, Fogel:

"So at the same exposure a larger sensor captures more light. Which is why a larger sensor tend to give less noise in images at the same ISO as a smaller sensor."

It's about the pixels, not the sensor. They are the capturers of light in a physics formula, not the wafer.

That's why DxOMark measured 9.6dB for the noise test at ISO 51200 for the K-5 IIs, and 9.8db at the same ISO for the K-1.
I only halfway agree with you. Yes, the print tab on DXO Mark gives you some sort of calculated averaging of noise and dynamic range. But is this calculation real world or just some made up thing?

If you look at a K5 and K-1 image at 100 percent, they will look exactly the same with regard to noise and dynamic range. If, on the other hand, you print both images at, say, A3 size, the K-1 image is going to look better. This makes sense because if you have more megapixels of the same quality, they help your final image, even if on a pixel level the dynamic range and noise for each individual pixel is exactly the same. I'm not smart enough to know if DXO Mark's calculations are valid, but I do know that to truly compare images you need to print them at the same size, not zoom in to the pixel level, when the number of pixels is vastly different from one camera to another.
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