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12-30-2015, 12:33 PM   #121
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QuoteOriginally posted by normhead Quote
35x23
36*24 surely...

12-30-2015, 12:36 PM   #122
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QuoteOriginally posted by Rico Quote
This could have been suggested already but Pentax should add an APS-H crop option as well. It can be done as it falls between FF and APS-C. Some DA lenses sweet spot may fall at APS-H size. Like several of the DA LTD's.

Isn't this all really moot though in the sense that why crop a FF sensor? I understand the need for cropping when a true APS-C lens is being used. But for lenses like the DA*55 DA*300 DA 560 used in the teaser shooting FF them cropping it later if need be should be the way to go.
Shoot in 35x23 mode and crop to whatever size you want. People seem to be overly concerned about the file size here. How are you going to feel the first time you use the 35x23 sensor in crop mode, and then don't get the crop you want, because you tossed useful information when you shot in crop mode? If I pay for a 35x23 sensor, I'm using a 35x23 sensor. Crop mode schmock mode. Unless I'm using my 18-135 with already vignettes a bit, I don't see any point. Even if I get APS-H instead of APS-c out of an image on my final crop... it's still more resolution.

---------- Post added 12-30-15 at 02:38 PM ----------

QuoteOriginally posted by bertwert Quote
36*24 surely...
I usually just post a rough number and wait for someone to correct me. You guys are slow today. That's about the 5th time I posted that number.

And don't call me ShIrley.
12-30-2015, 12:42 PM   #123
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QuoteOriginally posted by normhead Quote
That's about the 5th time I posted that number.
I know, I only just caught up on this thread right now.
I've got other things to do than read FF speculation threads...
12-30-2015, 12:45 PM   #124
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QuoteOriginally posted by bertwert Quote
I know, I only just caught up on this thread right now.
I've got other things to do than read FF speculation threads...
Ya right, everybody claims that, and yet, here they are.

12-30-2015, 12:48 PM   #125
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QuoteOriginally posted by normhead Quote
Ya right, everybody claims that, and yet, here they are.
I know, I did the other things and now I can speculate about FF
12-30-2015, 12:57 PM   #126
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QuoteOriginally posted by bertwert Quote
I know, I only just caught up on this thread right now.
I've got other things to do than read FF speculation threads...
I don't expect the FF to fit into my budget any time soon, but I've been keeping up with this thread, and making an occasional comment, because FF is where all the attention and "energy" are, so I figure that anything important to Pentax will be pulled in here sooner or later. FF has become Pentax's "black hole" in that sense, I guess. I just hope that something good eventually happens.
12-30-2015, 01:28 PM   #127
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QuoteOriginally posted by monochrome Quote
O. M. G. There really is a squirrel.

Ha! I know what you mean, I initially did not feel the need to open the link until I read the squirrel reference, and then opened. Otis appears again! I'm thinking that he got tired of the non-paid gigs.
12-30-2015, 01:56 PM   #128
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QuoteOriginally posted by normhead Quote
Shoot in 35x23 mode and crop to whatever size you want. People seem to be overly concerned about the file size here. How are you going to feel the first time you use the 35x23 sensor in crop mode, and then don't get the crop you want, because you tossed useful information when you shot in crop mode? If I pay for a 35x23 sensor, I'm using a 35x23 sensor. Crop mode schmock mode. Unless I'm using my 18-135 with already vignettes a bit, I don't see any point. Even if I get APS-H instead of APS-c out of an image on my final crop... it's still more resolution.
Agreed, I too will use the FF mode for everything, and I notice that Pentax seem to indicate some form of in-camera correction for vignetting etc., for suitable DA(*) lenses when in in FF mode.

FF mode will considerably extend the range of compatible lenses at the wide end and although I will in theory lose some resolution at the long end of say my DA*300 compared to the K-3, not so compared to the K-5. Anyway, I find it difficult to get maximum sharpness from the DA*300 handheld on the K-3 so in practice, I'll have a 200 to ~300mm DA* zoom (via cropping), very useful at say airshows as I have no zoom of comparable quality. At the other end, the DA 10-17mm fisheye should produce some "interesting" images in FF mode.


Last edited by Dave L; 12-30-2015 at 02:03 PM.
12-30-2015, 03:08 PM   #129
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QuoteOriginally posted by bertwert Quote
Bigger pixels!
I think this does not explain the large gap in the S/N numbers between FF and APS-c.

QuoteOriginally posted by bertwert Quote
Also newer sensors are better than older sensors.
Some APS-c sensors are also new. And, even older FF sensors yield much better noise figures than more recent APS-C ones.
12-30-2015, 03:10 PM   #130
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QuoteOriginally posted by bxf Quote
And, even older FF sensors yield much better noise figures than more recent APS-C ones.
Due to...
...
...
...
...PIXEL SIZE
12-30-2015, 03:18 PM   #131
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QuoteOriginally posted by bertwert Quote
Due to...
...
...
...
...PIXEL SIZE
Nikon D810 and Pentax k-5 have very similar pixel pitch...

---------- Post added 30-12-15 at 22:28 ----------

QuoteOriginally posted by normhead Quote
Because they don't normalize the DoF. Remember 35x23 is one stop shallower DoF. SO if you stop the 35x23 down to achieve the same DOF, and maintain shutter speed, you have to increase the ISO one stop, and both your total light and noise advantage are gone. The whole "better in low light" , "total light" advantage is predicated on using settings that give you narrower DOF. It;s been a slight of hand used by 35x23 protagonists for years.

Equivalence actually proves equivalence, not an advantage for one over the other.

The advantage to 35x23 is one stop shallower depth of field wide open, coupled with one stop better noise, shooting wide open. In any other circumstance, there is not advantage. People talk about wider angle shots looking more natural, there's a window where an FF image shot for narrow DOF looks quite a bit better than an APS-c shot at 35mm.. there are other advantages, but most of the other advantages are offset by higher pixel density of APS-c creating the illusion of more reach.

Because of the smaller pixels for equivalent APS_c the one stop more DoF at the long end, you'd expect to be an advantage for APS-c really doesn't exist. Shooting ƒ32 on APS-c to get that extra stop is so diffraction limited, it's not really an option.
I totally understand the DOF factor in the equivalence debate, and it is clear that if one strives for identical DOF and identical exposure, the FF noise advantage vanishes.

But DOF is not a factor in exposure, as are f-stop, shutter speed, and ISO. DOF, as I see it, is not a factor in the amount of light being transmitted. For any given f-stop and shutter speed, we are going to transmit a certain amount of light through the lens. Why does this quantity of light translate to such vastly different noise figures?

If I'm not mistaken, the large pixel and newer tech arguments have already been dismissed as being satisfactory explanations.
12-30-2015, 03:29 PM   #132
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QuoteOriginally posted by bxf Quote
Nikon D810 and Pentax k-5 have very similar pixel pitch...
D810 is newer than K-5... 4 years newer
12-30-2015, 03:34 PM   #133
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QuoteOriginally posted by normhead Quote
…And don't call me ShIrley.
I don't know: it kind of suits…

Just go with it.
12-30-2015, 03:49 PM   #134
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QuoteOriginally posted by redimp Quote
Both as in bigger sensor equates to more mp. Going on the correct figures, a K-5 APS-C sensor scaled up to FF would have 36mp. Therefore, if they are making a APC-C sensor with 24mp in the K-3, why not scale this up to give higher mp in the FF and 24mp in crop mode?
That would be a 54 MP sensor. Rule of thumb is that more MP comes with a trade off of less image quality (c.p.). See K-3 and 5dsr which both don't shine in low light and DR comared to lower resolution comparisons. So, with a FF 36 MP you have both a high resolution and high image quality.

If you want more of that, move to the Z and you'll have 50 MP and even better iq because the pixel density is even lower as on a 16 MP aps-c / 36 MP FF. (Roughly like 10 on aps-c and 22 on FF.)

With current technology we can't have all that in a small sensor, there is always a trade off between resolution and iq.
12-30-2015, 04:02 PM   #135
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QuoteOriginally posted by Alizarine Quote
When the DA 55-300 was first made, Pentax labeled it for digital and their digital was APS-C. It "may" cover the FF image circle somehow, but the point is that time it was made, Pentax was purely APS-C. So I think it cannot be safe to assume and say it has a "crop equivalent" of 450mm when it was designed for a system and labeled properly as 55-300mm too. It's the other way around. Sounds confusing but it isn't, if basing it from that point in time when majority of Pentax glass were purely APS-C
You have it backwards. If you use equivalence at all then a 300mm APSC is always going to give approximately the same Field of View on APSC as a 450mm FF lens on a Full frame. That's just the way it works. The focal length never changed and it has nothing to do with if the 300 covers the FF sensor or not. The cropped view is simply put - similar to the same field of view of a 450mm used on Full Frame.

The question really is if the 55mm end covers the full frame sensor and can actually give the same width on the Full Frame as a 55mm Full Frame lens or if it is limited to only covering the APSC crop. If the lens can cover the 55mm Full Frame adequately you can use one lens to cover the full frame equivalent of 55-450. If the 55 falls short and can't cover the full frame sensor then you have the same equivalence you have now 55*1.5=82.5 to 300*1.5 = 450 (82.5-450) in terms of Field of View. None of which changes the fact that it is always still a 55-300 it's just what you see in the viewfinder and on the sensor is different depending on sensor size and viewfinder size. Another way to think of this is that in terms of APSC equivalence it is like getting the equivalent of the APSC range of a 37mm-300mm range out of your 55-300. This is because the wide end is wider than you would expect (assuming coverage on the ff - which is admittedly not a given).

Think about looking with your eyes out a window - if the size of the window changes your view changes but your native eyes didn't. That's what happens with sensor size changes.
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