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05-07-2014, 02:27 PM   #766
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QuoteOriginally posted by ElJamoquio Quote
F/1.8 on APS-C is exactly as capable as F/2.8 on FF. Same DOF range, same SNR range. So it's really a straight comparison.

The F/2.8 zooms are generally wider and longer than the F/1.8. I guess the one exception is the olderish Tamron 28-75 that is no wider, but is still longer.
QuoteOriginally posted by ElJamoquio Quote
It's the same snr. No better, no worse. The iso readout on the ff says a higher number but it allnworks out to be the same (because of equivalence! )
That was what I was saying when I mentioned the noise although I wasn't very articulate and expected people to 'get' my meaning by implication

05-07-2014, 03:16 PM   #767
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QuoteOriginally posted by bossa Quote
That was what I was saying when I mentioned the noise although I wasn't very articulate and expected people to 'get' my meaning by implication
OK. The trouble I had was that you said the F/1.8 APS-C lens is faster than the F/2.8 FF lens.

They're the same speed in practical terms.
05-07-2014, 05:06 PM - 1 Like   #768
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Throwing SNR into the mix confuses things. It depends on what cameras you are comparing.

There are some newer APS-C sensors that will outperform some older FF sensors. You can't assume that just because somebody has FF, that they would be using the latest FF camera, since that can be quite expensive. There are probably plenty of people that can afford a new APS-C, but would have to settle for a FF that was a generation or two (or three) old.

All things being equal (meaning that the FF and APS-C sensor perform similarly), the f/1.8 lens will obviously allow you to use a faster shutter speed and/or a lower ISO.
05-07-2014, 05:20 PM   #769
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QuoteOriginally posted by Edgar_in_Indy Quote
Throwing SNR into the mix confuses things. It depends on what cameras you are comparing.
The entire discussion depends on sensor performance, and assumes equal performance between different sensor sizes. Fortunately for this discussion sensor technology has been stagnant and equal for Sony/Nikon/Pentax for the past 4 years.


If you'd like to see if the sensors are better/worse, you can, very easily, all you need to do is compare SNR at equivalent ISO's.

05-07-2014, 07:19 PM   #770
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QuoteOriginally posted by ElJamoquio Quote
The entire discussion depends on sensor performance, and assumes equal performance between different sensor sizes. Fortunately for this discussion sensor technology has been stagnant and equal for Sony/Nikon/Pentax for the past 4 years.

If you'd like to see if the sensors are better/worse, you can, very easily, all you need to do is compare SNR at equivalent ISO's.
What are the FF f/2.8 standard-zoom lenses that have shake reduction?
05-07-2014, 07:53 PM   #771
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QuoteOriginally posted by Edgar_in_Indy Quote
What are the FF f/2.8 standard-zoom lenses that have shake reduction?
Tamron 24-70
Anything on the Sony A7R, A7, A900, A850
Any K-mount sensors on the future Pentax FF


Glad I could help! Maybe you could help me... do you know any APS-C F/1.8 lenses that can resolve ~3700 lp/ph on older sensors?
05-07-2014, 08:05 PM   #772
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QuoteOriginally posted by ElJamoquio Quote
Tamron 24-70
Anything on the Sony A7R, A7, A900, A850
Any K-mount sensors on the future Pentax FF


Glad I could help! Maybe you could help me... do you know any APS-C F/1.8 lenses that can resolve ~3700 lp/ph on older sensors?
A7 and A7R do not have SR on the sensor.

---------- Post added 05-07-2014 at 09:25 PM ----------

QuoteOriginally posted by ElJamoquio Quote
If you'd like to see if the sensors are better/worse, you can, very easily, all you need to do is compare SNR at equivalent ISO's.
Tell me which of these crops is from a full frame camera and why you think so. I'll leave the discussion if you can spot it, these are all from the RAW files at low ISO on 16 MP models of a similar age.


Last edited by Mock; 05-07-2014 at 08:32 PM.
05-07-2014, 08:26 PM   #773
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QuoteOriginally posted by Edgar_in_Indy Quote
What are the FF f/2.8 standard-zoom lenses that have shake reduction?
AF-S VR Zoom-NIKKOR 70-200mm f/2.8G IF-ED

05-07-2014, 08:45 PM   #774
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QuoteOriginally posted by ElJamoquio Quote
Tamron 24-70
Anything on the Sony A7R, A7, A900, A850
Any K-mount sensors on the future Pentax FF


Glad I could help! Maybe you could help me... do you know any APS-C F/1.8 lenses that can resolve ~3700 lp/ph on older sensors?
I'll grant you the Sony SR, but you are aware that the VAST majority of FF cameras out there are Canon and Nikon, and for Canon and Nikon your only option that is truly equivalent to the 18-35mm f/1.8 is the Tamron. If you are using one of the nice Canon or Nikon f/2.8 zooms, then you may be giving up 2-3 stops when you are shooting handheld. Something to consider since you are including SNR in the mix.

Not that the Tamron is a bad option, but my point is that you cannot just lump all FF f/2.8 lenses together and say they are the functional equivalent of the 18-35mm. But then again, the Tamron is $1300, while the Sigma is only $800.

---------- Post added 05-07-14 at 11:47 PM ----------

QuoteOriginally posted by ennacac Quote
AF-S VR Zoom-NIKKOR 70-200mm f/2.8G IF-ED
That's a telephoto. I was asking about standard zooms that would be equivalent to the 18-35mm on APS-C. And for Nikon and Canon the only lens that can replicate the 18-35mm f/1.8 on a Pentax is the Tamron 24-70mm f/2.8 VC. There are no first-party equivalents from Canon and Nikon.

Last edited by Edgar_in_Indy; 05-08-2014 at 10:51 AM.
05-07-2014, 09:24 PM   #775
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QuoteOriginally posted by Mock Quote
I'll leave the discussion if you can spot it
Why? I'd like for you to stay in the discussion.
05-07-2014, 09:26 PM   #776
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QuoteOriginally posted by ElJamoquio Quote
Why? I'd like for you to stay in the discussion.
Alright, if you insist, but please take my challenge. Is it not so easy?
05-07-2014, 09:28 PM   #777
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QuoteOriginally posted by Mock Quote
Alright, if you insist, but please take my challenge. Is it not so easy?
The one on the upper left looks the best to me.

But there are many, many, many ways to screw up the testing... so I usually decline to take the test.

That looks like it might've been an Imaging Resource pic? They get a lot of things wrong.
05-07-2014, 09:47 PM   #778
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QuoteOriginally posted by ElJamoquio Quote
The one on the upper left looks the best to me.

But there are many, many, many ways to screw up the testing... so I usually decline to take the test.

That looks like it might've been an Imaging Resource pic? They get a lot of things wrong.
Don't blame the test. The source is dpreview, I screen-capped the page, cropped out the relevant part of the page, painted over the camera-identifying information with a rectangular marquee selection so I did not contaminate the images, and then saved it as a lossless PNG file.

Last edited by Mock; 05-07-2014 at 10:06 PM.
05-08-2014, 02:04 PM   #779
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top left is the image that looks best to me, but that does not necessarily mean it was the FF camera.

I will go with either top right or bottom left as the FF, with me leaning towards the bottom left image and I would even go so far as to say it's a canon. I'm stating this on color reproduction.
05-08-2014, 03:03 PM   #780
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QuoteOriginally posted by Wired Quote
top left is the image that looks best to me, but that does not necessarily mean it was the FF camera.

I will go with either top right or bottom left as the FF, with me leaning towards the bottom left image and I would even go so far as to say it's a canon. I'm stating this on color reproduction.
Thanks for responding.
I'll reveal all once ElJamoquio actually answers properly which one he believes is FF and why based on the relative SNR alone.
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