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01-04-2016, 02:39 PM   #286
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QuoteOriginally posted by normhead Quote
Too, funny, everyone does it so it must be right. Having had academic parents, that kind of argument would have seen me laughed into the next county. That's not proof. That's an admission that you're a victim of herd mentality.

What does this have to do with under-exposing? If you understand equivalence, you'd understand under-exposing is not part of the equation.

APS-c- ISO 100, ƒ5.6, 1/50s
36x34- ISO 200, ƒ8, 1/50s
The underexposing is so you can measure the same amount of noise at the same ISO on both APS-C and FF, because it seems to be breaking some sort of taboo suggesting that FF has better ISO noise performance than smaller sensors.

When I earlier suggested "The normal procedure to compare noise is to compare at the same ISO with same light conditions." it was commented as "You mean the endless pro full frame drivel that gets posted on the web?..." and "Then your "normal" is apples versus oranges..."

And when I suggested "I mean, stopping down the lens one extra stop on FF do not change anything in the measurement as one stop slower shutter speed will then be used" it was commented as "Sorry, but that's the 36x24 cool aid speaking..."

So by using...
APS-c- ISO 100, ƒ5.6, 1/50s
36x34- ISO 100, ƒ8, 1/50s
Both capture the same same image and same ISO noise performance can be measured on both for the same ISO.
Everyone happy?


QuoteQuote:
The big question I would like answered, is why did all those people on all those sites publish all those tables, comparing different images?

The question is why did all those folks you talk about do this?
APS-c ISO 100, ƒ5.6, 1/50s
36x24 ISO 100, ƒ5.6, 1/50s

The 36x24 image uses double the light and there for has a stronger signal and has better signal to noise... but it's not the same picture, the DoF is different.
They use these exposure settings because they measure noise at a specific ISO, using equivalent DOF would not change anything as they then have to compensate with shutter speed to not underexpose the FF image, and the larger sensor will still capture twice as much light and the ISO noise performance would be exactly the same as if both use the same f-stop.


Last edited by Fogel70; 01-04-2016 at 04:18 PM.
01-04-2016, 02:50 PM   #287
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100% agree with normhead, for most image there will be almost no visible difference.

Sure on some case the FF get an edge and if you know your gear you'll use it to its strengths but this is not the night and day affair some people want us to think of.
01-04-2016, 02:52 PM   #288
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QuoteOriginally posted by Fogel70 Quote
and "Then your "normal" is apples versus oranges..."

APS-c- ISO 100, É5.6, 1/50s
36x34- ISO 100, É8, 1/50s
Both capture the same same image and will same ISO noise performance can be measured on both for the same ISO.
Everyone happy?
Not.

One of the two now is exposed -1 EV versus the other, or simply put: quite a bit "darker". I would not consider this "the same image". And few people would.
01-04-2016, 03:08 PM - 13 Likes   #289
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I think this discussion is starting to get ridiculous! Happy with APS-C and dont need FF? Fine for you! In my line of work, there is a BIG difference between FF and APS-C. Even Nikon's old D700 walks all over K-3 II on ISO. Only reason i still are loyal to my contract, is that i really belive in what is coming and Ricoh are real good to me.

I got warned about the stupidity on this forum..too bad i didn't belive it was this bad.

01-04-2016, 03:11 PM - 1 Like   #290
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QuoteOriginally posted by Fogel70 Quote
APS-c- ISO 100, ƒ5.6, 1/50s
36x24- ISO 100, ƒ8, 1/50s
Both capture the same same image and same ISO noise performance can be measured on both for the same ISO.
Everyone happy?
The most common case were FF get a benefit and justifiy the better number is:
APS-c- ISO 100, ƒ5.6, 1/400s
36x24- ISO 50, ƒ8, 1/100s
The FF picture will have better quality, more dynamic range, more definition etc... The only practical issue is that to really see it you would need a 60" print and an high end FF with 36MP+.

Another case is:
APS-c- ISO 1600, ƒ/2, 1/50s
36x24- ISO 3200, ƒ/2.8, 1/50s
Noise is comparable but the FF guy can use an f/2.8 zoom (like a 70-200) while on APSC you'd need a fast prime. This is quite common case for shooting events (weddings...) and maybe the biggest reason for a pro to get an FF.

And of course ultimate shallow deph of field
APSC ISO 100 f/1.4 24mm
36x24 ISO 100 f/1.4 35mm
When you want to isolate a big subject with a WA, there always too much deph of field. If you can't use a tele instead (not enough working distance to have the whole,subject) or if you want the perspective rendering of a WA instead of a tele, then you need a fast WA. But that's a very specific use case.
01-04-2016, 03:17 PM   #291
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QuoteOriginally posted by Fogel70 Quote
They use these exposure settings because they measure noise, using equivalent DOF would not change anything as they then have to compensate with shutter speed to not under exposure the FF image, and the larger sensor will still capture twice as much light and the ISO noise performance would be exactly the same.
QuoteQuote:
They use these exposure settings because they measure noise,
Setting don't measure anything.

QuoteQuote:
using equivalent DOF would not change anything as they then have to compensate with shutter speed to not under exposure the FF image,
No they wouldn't, they would have to change ISO to maintain shutter speed, which is what I did.

There is no logical reason for going with your assumptions of how this should be done, You are simply trying to justify how all mistaken people did it.
01-04-2016, 03:21 PM   #292
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QuoteOriginally posted by kenspo Quote
I think this discussion is starting to get ridiculous! Happy with APS-C and dont need FF? Fine for you! In my line of work, there is a BIG difference between FF and APS-C. Even Nikon's old D700 walks all over K-3 II on ISO. Only reason i still are loyal to my contract, is that i really belive in what is coming and Ricoh are real good to me.

I got warned about the stupidity on this forum..too bad i didn't belive it was this bad.
Happy new year ken,
Let's hope the waiting gets only shorter now
01-04-2016, 03:24 PM - 1 Like   #293
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QuoteOriginally posted by Zygonyx Quote
Happy new year ken,
Let's hope the waiting gets only shorter now
Happy New Year! And the waiting is getting shorter as we speak

01-04-2016, 03:26 PM   #294
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QuoteOriginally posted by kenspo Quote
I got warned about the stupidity on this forum..too bad i didn't belive it was this bad.
This isn't bad. When it gets really bad you click the little button on top that says "Unsubscribe from this thread". Usually when they start arguing about stuff like the above I just tune out. I'm not technical enough to understand what they are talking about anyway. And the only thing that matters to me is what MY pictures look like so whatever someone else needs/wants is irrelevant to me.

Glad you are sticking with Ricoh, it must be frustrating not having the gear you have been told about. But hopefully it will not be much longer.
01-04-2016, 03:28 PM   #295
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QuoteOriginally posted by normhead Quote
There is no logical reason for going with your assumptions of how this should be done, You are simply trying to justify how all mistaken people did it.
Are you going to contact all test sites that test camera and tell them they are doing their comparisons wrong, and tell DxOmark that they have to change the way they draw their graphs, so that FF cameras at ISO400 is compared with APS-C at ISO200 and mft at ISO100?
01-04-2016, 03:32 PM - 1 Like   #296
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QuoteOriginally posted by kenspo Quote
I think this discussion is starting to get ridiculous! Happy with APS-C and dont need FF? Fine for you! In my line of work, there is a BIG difference between FF and APS-C. Even Nikon's old D700 walks all over K-3 II on ISO. Only reason i still are loyal to my contract, is that i really belive in what is coming and Ricoh are real good to me.

I got warned about the stupidity on this forum..too bad i didn't belive it was this bad.

Amen.

Yes I am going to get a full frame when it comes out. Simple reason. My old eyes simply do a lot better with a full frame viewfinder. Plus if it has a split image viewfinder with a wonderful micro prism circle around it I will be in hog heaven. If not, maybe a viewfinder from one of my old Ricoh XRM's or Pentax film cameras will work in it.
01-04-2016, 04:17 PM   #297
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QuoteOriginally posted by gaweidert Quote
Plus if it has a split image viewfinder with a wonderful micro prism circle around it I will be in hog heaven. If not, maybe a viewfinder from one of my old Ricoh XRM's or Pentax film cameras will work in it.
Amen to that! I fear we will have to still rely on very imperfect autofocus (many shots I've missed due to that, GRRR) but if it were to have the split image thing it would be a big selling point for me, I really miss them from my MX days. Never have really got on with ground glass screens but i know there would be big technical issues to overcome to get split screen focussing working properly.
01-04-2016, 04:24 PM - 2 Likes   #298
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QuoteOriginally posted by kenspo Quote
I got warned about the stupidity on this forum..too bad i didn't belive it was this bad.
Anticipation makes people crazy...

01-04-2016, 04:45 PM   #299
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QuoteOriginally posted by kenspo Quote
Happy New Year! And the waiting is getting shorter as we speak
I understand that is not as good for you to use an APSC theses days but so what do you do? Do you have to always have a Pentax while waiting for the FF? Or do you happen to use an FF from another manufacturer in the meantime?

If you can't use anything else than Pentax and you are actually making money from your photos, outside of the Ricoh contract did you notice a relevant drop in income due to lower quality pictures coming from having only an APSC body?
01-04-2016, 04:55 PM - 1 Like   #300
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QuoteOriginally posted by kenspo Quote
I think this discussion is starting to get ridiculous! Happy with APS-C and dont need FF? Fine for you! In my line of work, there is a BIG difference between FF and APS-C. Even Nikon's old D700 walks all over K-3 II on ISO. Only reason i still are loyal to my contract, is that i really belive in what is coming and Ricoh are real good to me.

I got warned about the stupidity on this forum..too bad i didn't belive it was this bad.

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