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02-22-2012, 08:35 PM   #196
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QuoteOriginally posted by Zygonyx Quote
Hence the crop factor equal to sensor's diagonal ratios, rather than to "size" ratios
To be precise, the crop factor is equal to the ratios of the square root of sensor area. This makes the result invariant WRT aspect ratio.

(I cover this in one of my articles on the subject -- see blog.)

02-22-2012, 09:43 PM   #197
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QuoteOriginally posted by falconeye Quote
Another reason why I wrote this
-> Falk Lumo: Camera equivalence (click the title)
Falk, I only quickly checked out your article and still have to read it in full, but I stumbled across your statements about dynamic range.

You argue correctly, that equivalent settings produce the same scene referred dynamic range independently of sensor size.

But clearly a larger sensor allows settings that have no equivalent for the smaller sensor. Imagine a scene that just about fully saturates all sensels of the small sensor. On the big sensor, the same total amount of light is spread over a larger area, thus reducing the flux. In other words, sensels on the larger sensor will not be fully saturated yet.

If we further increase the total amount of light, the larger sensor can still reduce the ISO value, whereas the smaller cannot anymore and will blow out highlights. This will also translate into better SNR figures (which may not be a fair comparsion because the images aren't equivalent anymore, but the fact remains that the smaller sensor cannot cope anymore).

Sorry if I just misread or skipped too much of your article.

Last edited by Class A; 02-22-2012 at 10:09 PM.
02-22-2012, 10:07 PM   #198
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QuoteOriginally posted by falconeye Quote
I am sorry, but boldface postings make me blind.

Krruazifix nochomoal

Don't exactly know what it means, but the leaderhosen wearing guy at the Munich beer hall table next to mine yelled this when he spilled his beer. I had heard it many times in Munich so I wrote it down phonetically and I am using it her now in the hope it is appropriate. (If not, I beg your forgiveness)

I wonder, what is the fascination and dislike over the occasional bold typesetting practice to make text more legible. Any trained compositor will learn to apply this text formatting practice in the interest of said legibility. So why do take forum members offense to it when there is no obvious personal accusation/malice intended ?

I know it's totally off topic , but...

Greetings
02-22-2012, 11:01 PM   #199
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QuoteOriginally posted by recando Quote
Well FF is nice but I doubt that the IQ will be much better! especially in the corners. The K5 has a pretty good quality and if you compare it wit the D700 there is no big difference on IQ (checkt on DxOMark - DxOMark by DxO Labs).
Pentax says they are keen on searching for niches for there products.
Well I really do not want a nich product!
I just want good quality to a reasonable price. Nothing more or nothing less.
If you are just shooting landscapes, yes.. take in to account Nikon's far superior AF system, better brighter FF viewfinder, better flash system, shooting at 10 FPS w/Battery Grip and you will start noting the differences in the amount of keepers and camera abilities. I did love my K-5, but I'm ready for the upgrade.

02-23-2012, 01:10 AM   #200
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QuoteOriginally posted by Chex Quote
If you are just shooting landscapes, yes.. take in to account Nikon's far superior AF system, better brighter FF viewfinder, better flash system, shooting at 10 FPS w/Battery Grip and you will start noting the differences in the amount of keepers and camera abilities. I did love my K-5, but I'm ready for the upgrade.
I'm not sure if FFA (full-frame addiction) is not your main problem Having played with D300, D700, D2x and D3s I'm not sure that K-5 is *really* that bad. Surely, Pentax needs to improve in many areas but is the technology *really* the limiting factor here?
02-23-2012, 02:29 AM   #201
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QuoteOriginally posted by Chex Quote
If you are just shooting landscapes, yes.. take in to account Nikon's far superior AF system, better brighter FF viewfinder, better flash system, shooting at 10 FPS w/Battery Grip and you will start noting the differences in the amount of keepers and camera abilities. I did love my K-5, but I'm ready for the upgrade.
If I had the money, I like to use the best camera on the market...
So I have to choose a camera I can afford.. The FF has it´s advantages, shure.
But the cheaper sensors get better. So the IQ differnce is not so big now.
Well lets wait for D4 and D800, and talk agin.
02-23-2012, 02:45 AM   #202
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Check out todays Dilbert... something about niche market :-D
02-23-2012, 05:22 AM   #203
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QuoteOriginally posted by elho_cid Quote
Check out todays Dilbert
yeah..... maybe we should get our minds out of our niche...

02-23-2012, 07:19 AM   #204
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QuoteOriginally posted by rparmar Quote
To be precise, the crop factor is equal to the ratios of the square root of sensor area. This makes the result invariant WRT aspect ratio.

(I cover this in one of my articles on the subject -- see blog.)
Yes, thank you and congrats for your blog/photos
02-23-2012, 10:48 AM   #205
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QuoteOriginally posted by rparmar Quote
To be precise, the crop factor is equal to the ratios of the square root of sensor area. This makes the result invariant WRT aspect ratio.
Because this got cited, let me respond to it.

The crop factor is indeed defined by the ratio of sensor diagonal or image circle diameters. This is so because Field of View (an angle) is defined this way.

What you refer to is important when it comes to discussions related to noise. But it isn't the crop factor. It only differs if the aspect ratios differ. However, then every discussion will have to assume a given aspect ratio of the final product. This makes such discussions inconclusive and it is best practice to use the image circle ratio even in discussions related to image noise if the final aspect ratio is an unknown. In my article, I did the same by simply ignoring the issue on purpose.
02-23-2012, 11:17 AM   #206
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QuoteOriginally posted by falconeye Quote
Never again I want to hear the words "niche" and "full frame" together in one sentence
Nikon sold 22 million cameras in 2011.
Even if they sell 0,6 million FF per year, that'd be 2,7% vs. 97,3% others. A niche it stays.

PS: This excludes people who keep mobile phones for making pictures, which will be not a small number of people.
02-23-2012, 11:29 AM   #207
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Transcript??

Adam, I'm still hoping to find that [English] transcript. Have you posted it anywhere here or in any other thread?

To stay on-topic in this thread, evidently we are required to add at least one spurious comment about FF. OK, here's mine:
I'm thankful that Pentax/Ricoh clearly has NO plans to sell a FF body -- because it means upcoming K-mount lenses may take full advantage of APS-C crop factor and better high ISO, by being smaller and lighter. With a little luck, such lenses will also be slightly less-expensive, or more likely, have slightly better glass or more features (WR?) at whatever price point Pentax has chosen to aim at.

My personal dream is for a DA 200-560 f5.6 LTD WR at half the weight of a Bigma, and a US$999 price point.
02-23-2012, 11:46 AM   #208
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QuoteOriginally posted by beholder3 Quote
Nikon sold 22 million cameras in 2011.
Even if they sell 0,6 million FF per year, that'd be 2,7% vs. 97,3% others. A niche it stays.

PS: This excludes people who keep mobile phones for making pictures, which will be not a small number of people.
We say only about DSLR cameras...Nikon couldn't sell 22 millions of DSLR
02-23-2012, 02:37 PM   #209
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QuoteOriginally posted by falconeye Quote
The crop factor is indeed defined by the ratio of sensor diagonal or image circle diameters. This is so because Field of View (an angle) is defined this way.
Well, which is it then? Image circle diameter is not the same as sensor diagonal, since there are no circular sensors.
02-23-2012, 03:30 PM   #210
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QuoteOriginally posted by rparmar Quote
Well, which is it then? Image circle diameter is not the same as sensor diagonal, since there are no circular sensors.
I don't see the difference. The diagonal of a rectangle is the same as the diameter of the smallest circle it will fit in.
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