[Mash4077]

Thanks everyone for the thoughts and advice.

Seems the majority are suggesting the K1 route rather than the K3II route. From reading around it seems there is little to no information yet on a replacement for the K3II.

[interested_observer]

From reading around it seems there is little to no information yet on a replacement for the K3II.

Nothing heard and no hints. That said, and this is pure unadulterated speculation - a WAG (as in Wild A$$ Guess). Just trying to think out loud.

The K1 was just released, and both the crop sensor (K3 seems to indicate about an 18 month replacement cycle) and the 645 product lines have to be in the design and development pipeline. Also, there must be some forward thinking going on in terms of what the K1 replacement will offer. That tends to point to the crop sensor (K3II replacement) as the next release (in 2017) - which makes sense. The K70 was released in very short order with a fair amount of capability from the K1 - which will indicate that the crop replacement will need to outshine the K70 by a substantial capability margin. Pentax will need to take some risks on both the new 645 (at a 4 year cycle - so 2018?) and the K1 replacements - so to mitigate and reduce this risk on their premium product lines, they will use the crop replacement as the experimental platform for any new technology. The rumored new Nikon D7300 is though to be continuing with the current sensor technology. Going to a new sensor technology now, would get Pentax a step ahead, while affording Pentax the ability to always fall back to the technology in use, if things do not pan out. It's always good to have a risk-less Plan B for a backup.

So, what is the new technology that may be currently available? In terms of sensors its the new Sony IMX378 Stacked BSI CMOS sensor - or the Backside illumination technology. Sony used it in their newest release of the A7R mk II.

• Sony IMX378: Comprehensive Breakdown of the Google Pixel's Sensor and its Features

All of the following speculation is just extrapolating off of the A7R mkII - which is dangerous, but the only data point really available. So, here is the dive into the swimming pool - hopefully with some water...

• PDAF Auto Focus - Pentax could possibly use this to help continue to modernize their AF. How they may do this without lifting the mirror for the OVF is a problem with this approach.
• High Frame Rate - This could help Pentax with their continuous AF, and improve their video, especially with video AF while recording, and may afford them the ability to go to 4K video. Pentax could probably use this in their Pixel Shift to reduce the amount of time between exposures - gated by the amount of time required for the sensor movement.
• SME-HDR - I am going to wonder out loud, if Pentax is considering possibly combining their Pixel Shift with this new Spatially Multiplexed Exposure HDR approach. Pentax should also be able to improve their in camera HDR capability along with possibly doing something with the traditional bracketing.

What might this mean for some of the more traditional measurements. Using some currently available measures web sites to help here..

• https://www.dxomark.com/cameras#hideAdvancedOptions=false&viewMode=list&yDataType=rankDxo
• The Sensor Noise DB. – Brendan Davey Photography

The links above, provide measurements across both the A7R and the A7RmkII, which marks the transition to the BSI CMOS sensor.

• ISO - Sony between the A7R and the A74mkII appears to have improved their DXO sport score (ISO) by 25% or that would be about 1/4 of a stop - up to ~ 3400 (full frame). The K5IIs is at 1208, so a 25% improvement would push it to about 1500 which would be very nice and make it the best APS-C score. The K3 was a step back from the K5 for Pentax. If they could step forward here, that would be tremendous. In the Sensor Noise Database, the chipouts do provide a numerical measurement of mean, standard deviation and median valuations. What is interesting here is that the A7R's histogram values were reasonably flat (level) across the exposure times (1, 30 and 300 seconds), while the new sensor had substantially increasing values - essentially doubling (from 1 sec to 300 sec). The BSI CMOS sensor's construction has the circuity under the photosites, while reducing the distance between them. I am going to guess heat, that thermal dissipation is a larger problem with the new sensor technology. Thermal transfer and dissipation will be an increased problem for the packaging engineers - which means the camera bodies are not going to get any thinner.
• Resolution - The A7RmkII went to 42MP, scaled to a crop sensor, that would put the size in the neighborhood of about 28MP - not that we need any more MP. Perhaps Sony would reduce the resolution (maintaining 24MP) to make the photosites larger, which may lower noise at higher ISO values. Having larger pixels should also help with dynamic range.
• Dynamic Range - Sony was able to keep the A74mkII DXO landscape score (DR) at 13.9 a small decrease from 14.1. Hopefully, Pentax could keep it in the 14 area - hopefully at the high end of 14.

I'll also guess that the replacement will have something like the K3 body with either the K1 or K70 articulating rear screen, built in GPS and WiFi, along with coming in the color of basic black - for $1100 to $1200 (the rumored price of the new Nikon D7300).

That's my guess for the K3II replacement. Having said all of that - what ever it comes in with, it will still be a stop behind the K1 just based on sensor real estate.

[Mash4077]

Having spoken with Pentax and Sigma this morning it appears that the only lens I have that works FF is the 150-500 all the rest will not work and would need to be used at crop mode.

I am wondering if one option open to me would be to jump K3II with a black friday deal (assuming one crops up) and work on changing over my lenses (or certainly the ones I use the most) and then changing the camera to FF which maybe a case of it then being the K1 replacement.

[C_Jones]

The K-3II will show you the most advanced performance of the Pentax APS-C camera line. It is noticeable. K-5IIS is an exceptional performer, but the K-3II is the advanced performance body. I have both, as I mentioned before. To satisfy the APS-C category the K-3II is a wise decision, you would not be backtracking, and later if you want to switch to the K-1 you will have that option.

[MikePlunkett]

Having spoken with Pentax and Sigma this morning it appears that the only lens I have that works FF is the 150-500 all the rest will not work and would need to be used at crop mode.

The key word that both Pentax and Sigma will have left out from their advice is officially as in, the only lens you have that officially works FF is the 150-500. In practice quite a lot of your lenses will do just fine at FF. The DA 35mm f2.5 and DA 50mm f1.8 do extremely well FF with only small amounts of vignetting when wide open (easily removed in post processing). If you want to check how the rest of your Pentax lenses do take a look at the Pentax K-1 Laboratory which has a very comprehensive set of test photos taken with most (if not all) Pentax lenses on the K-1.

Bottom line, I was originally going to upgrade from an original K-5 to a K-3II but decided to wait and instead make the bigger jump to the K-1 and do not regret that decision in the slightest. It is an absolutely incredible camera and while the K-3II may be great too I can't help thinking you'd end up kicking yourself for not going the whole hog!