FPN shows mainly in Shadow areas of Canon Eos: 5d-III 6d-II 7d-II... included Eos 5D Bias-Map Fixed Pattern Noise, FPN - Click Image, Ctrl+ to Enlarge
The way the sensor's designed leads to high Pixel Response Non Uniformity.
Power Supply corrupts sensor Analog Signal before ADC: Electronic Noise?
Even a 30 sec. Mid Exposure at ISO 100 in Low Light is a Banding disaster: Canon Eos DSLRs are mostly Unusable at Low-ISO setting in Low-Light
Lifting Shadows was very touchy in PP with almost all these Canon DSLR. In
AstroPhotography, we used to Subtract a Bias-Map (offset frame) from each
Raw file. So, it was more of a pain to deal with the Amp-Glow at bottom-right.
High Conversion Noise, Signal Corrupted fore ADC: Canon Eos (x)xD...2019
FPN unseen by Dxo method is back here - Clic Image, Ctrl+ Enlarges
Pentax K5 Revolutionary imx071 Exmor, see this 5 min. ZWO Dark-Frame imx071 Dark-Frame 1000x less Noise, 0 Amp-Glow - Click Image Enlarges
The way the sensor is designed cancels 99% Pixel Response Non Uniformity
Nothing really can Corrupt sensor Digital Signal output = close to Zero Noise.
Long Exposures in Low Light at ISO 80 protecting High Lights are a pleasure
The frame is totally free of Amp-Glow even on a 300 seconds Long Exposure.
--The howto both images are from and made is written in their IPTC infos.
Pixel Response non Uniformity Levels have been Reduced a lot. Tartan Fabric,
Fixed Pattern Noise and Banding were totally absent since the Pentax K5 Sony
imx071 "Exmor" sensor. An analog Correlated double Sampling circuit before Analog to Digital Converter, plus a Digital CdS After the ADC lowers the PRnU
levels to never seen levels. Astro Pics from Exmor Sensor w/o any other Frame
that 3,4 Flat-Fields and only a few SubFrames are far better than what I got w/...
Exmor sensor ADConverter + Digital CdS Timing Chart Click Image, Ctrl+ to Enlarge
Stacking is very efficient to Maximize the SNR of low Light Raw files that include
an imperative " Only Random Noise inside the Raw files " Condition.
RAW Smoothing Destroys the ' Random Noise Only ' Condition by introducing
Artifacts and by Erasing many Faintest True Stars from the Raw files. Astro Pics Pentax Q10 w/ 4 min. exposures and w/o Raw-NR beats Samsy NX mini
require True RAW. Avoiding any Raw Smoothing or Star Eating. The Smoothing
of K5's RAW files begins at ISO 2000. Who will use the Pentax K-5 at ISO 2000
knowing that it doesn't have any Analog Amplification after ISO 80. It's far easier
to get very hight SNR stacking a handful of ISO 80 Long Exposures than with 60
ISO-1k6 30sec. Expos. Am I still the only one using his PK-5 at its best ISO 80 ?
Of course, you may keep shooting Astro-Photography at Hight ISO settings.
But, for the K5(II(s)), when shooting at ISO-80 instead of ISO-12800 : Constant Light Value =160x more photons from 12800 to 80
+ ISO 80 DR Value 14,1 = ~twice ISO 12k8 DR-#...
... it's ~17929 vs only ~155 Luminance Values (Print).
+ ISO 80 SNR Value is ~2 times~ ISO 12k8 Value...
... this means ~42 dB instead of only ~21,3 dB ! (Print).
- ISO 12k8 Raw file Size is about ~twice ISO 80 Raw Size...
... this Huge Difference in File Size is due to NOISEs included !
- ISO 12k8 makes you Stack Much More Sub-Frames to get rid of Noises.
- ISO 12k8 implies to Subtract Bias-Maps, Dark-Frames to Clean Sub-Frames Pentax K-5 Astro-Photography at ISO-80
Bad habit to shoot at Hight ISO-Setting in Low-Light began w/ Eos DSLRs :
100% unable to get Raw files w/o Banding, FPN, Tartan Fabric at ISO 100-400.
Eos 20d, 5D, etc's Optimum Setting is ISO-1600. ISO-800 in Warm-Summer.
For Astro-, Bird-Photography, there are not so many APSC ILCs available with a Crop Mode down to 4:3 or 1" for stills. Now that they all get Fully Addressable CIS, CMos Image Sensor, RoI, Region of Interest, is a 100% CostLess Option. Very useful for Astro-Photos of Deep Sky Small Objects or Bird photography.
Let's examine 2 pairs of APSC DSLRs through P2P.net, a Used vs a New one.
Click Image, Ctrl+ Enlarges
Used APSc cameras. Pentax K5(II(s)) better Eos 60d in every characteristic, except for the Read Noise where the 60d's slightly better. Canon DSLRs were at Top of Conversion Noise. Eos-60d: 8.5 vs PK-5: 0.6. Red Layer especially suffers from that Huge Conversion Noise level. A Stock Pentax K5 with UHCS filter shows at least equivalent Red Performance than an Expensive Eos 60dA. The proof is here : dpreview.com/challenges/Entry.aspx?ID=1195990 dpreview.com/galleries/7467909648/photos/4208343/pentax-k5-rosette Note the 52mm secondary mirror of my 200/1000 SkyWatcher is far too small.
At least a ~70mm 2nd Mirror, to light ~24mm Circle in 28mm Diagonal CMos.
Pentax K-5 is Weather Sealed, its specified min.operating Temperat°C is -10. K-5 also has a very low Dark Current level so that you can Expose until 30 min. ISO 80 by 12-25°C Ambient Temperature and get so Clean Raw files that any Bias Map, Dark Frame's useless. In most cases, you only need 3-8 Raw files : www.DPReview.com/Galleries/Tags/ISO-80 17 min. Exposure through an UHCS filter to darken M-51. Then Pushed 6 Ev : www.cloudynights.com/gallery/sizes/32054-pk5lv-5-6/large/ Not a bit of Banding, nor any Fixed Pattern Noise. Not even only 1 Hot-Pixel ! Pentax K5 is IsoLess, far Better results are achieved stacking ISO 80 subs to get a High SNR image you can Push, than a lot of ISO 1600 subs as you have to with Noisy Canon DSLR near Base-ISO. 1st Exception in last Eos R5 +R6. Image-Quality Bonus is huge from ISO 1600 up to 80 : A look at DxO Curves. SuperBonus : 20x more photons from 15 to 300sec. imx071 exmor sensor in the PK-5 is so fine that chinese camera makers did not hesitate launching their Asi071, Qhy168C, etc. at Top Price of $3000€ = 3 times, 3x the Price I bought my Pentax K-5 New in Mars 2011. Models are still available ~1/2 2/3 that price, see how low is their imx071's Dark Current level: ZwoAstro.com/Asi071mc-Pro~Cool
Replace 'Cool' by 'Pro'. Add '+Manual' in Browser's Search-bar for more infos:
= 1st "Exmor" CMos sensor. Still in the Race after ~15 years on the market.
The 1st CMos sensor w/o any Amp-Glow.
Click Image, Ctrl+ to Enlarge
New APSc Camera: to buy an APSc camera for Long Exposure in Low Light or Astro-Photo today, I would certainly choose a Nikon D7500 over the Canon Eos 80d. Pentax K3-I, II, III are Not at the IQ level of the K-5. The later do Need Strong Raw Smoothing to follow Modern Dual-Gain BSIs. Proof, the K-3 Mono w/ imx571 doesn't need that strong Raw NR to gain 2+ Ev DR. The Eos 80d is now closer to the Pentax K5, but 6 years later, the Nikon D7500 beats them all in all characteristics. Except the K5 for Close DR and Long Exposure Noise : www.brendandaveyphotography.com/more/Long-Exposure-Sensor-Tests Pentax K5 is still the Long Exposure King, far less Noisy than either the D500 and the D7500 which share very Similar sensors, if not exactly the same. Eos 80d is roughly in between both for long exposures, but way more Noisy than both the Nikon and the Pentax for Exposures of 30 seconds or shorter.
Click Image, Ctrl+ to Enlarge
DxoMark don't allow comparing more than 3 camera. But it wasn't that difficult to add the Canon Eos 60d over the screen shots of the 3 other DSLR. Canon Eos 80d, Pentax K5, Nikon D7500, here sorted by their IQ Performance rate.
Nikon-D3X-vs-Sony-Alpha-850-vs-Pentax-K5-Perfs-Compared The Pentax K5 beats all these Flagships in almost every criteria measured by DxoMark. Except the Nikon D3x's better of 1 bit Color-Depth in Portrait Mode. But, it was launched at ~$8800 - more than 8x the price I paid for my K-5 New PENTAX, me revoila : mon K-5 arrive juste ! The better ISO score of 24x36 is logical, it's because their 2,33x sensor Area. All other things kept equal Dxo-ISO score is function of sensor's 2 dimensions Low-Light Photography + Sensor Sensitivity Comparison Tools for Astronomy The 24x36s are far from reaching ISO 2707 ; The Sonys are only 1,2x the K-5. Dynamic Range Ability to show Noiseless Details from the Deepest Shadows. Here the K-5 shines: 2,4 Ev better than the 2012 Eos 5dIII, 1,8 Ev better than the Sony Alpha-900, 1st DSLR to implement an OnSensor ADC, an Analog to Digital Converter prevents aSaP the Signal to be ruined by Conversion-Noise External ADC, Weak Filtering PSU, Weak Shielding, ruin the Dynamic Range
2010. Sales of Samsung NX cameras took off quickly. Everyone noticed the Fine Colors they got. A few months later, was the turn of
Sony-Nex. Adapters Makers, Sellers, were popping up everywhere. Brands' Lens Systems always closed, opened quickly. 2012 was
Fujifilm X moment. Ricoh released its k-01, their 1st and Last APSc MirrorLess. Then you could use almost Every Lens on a ML camera:
Samsy NX, Sony E, Fuji X. Except Ricoh that was 100% wrong keeping its big K Mount, thus depriving itself of using all other lenses
available new or used, on its cameras. This was a Big Mistake - would have been Much Better to provide the K Adapter at a low price to the K
users. Especially since the k-01 didn't shine by any decisive advantage: as Big as a K-5 and crippled by a Slow hesitating AF in Low light.
Worse, No EVF available and 12 bit only RAWs. 4 years later, you could always buy a k-01 New for less than a Quarter of its launch price... 2013 Diagram of K-01 Fiasco - Click to Enlarge
Despite having 50% More pixels (Print) +being 5 years younger, the K3,II show slightly lower performance than the D7k ~5 years ago. The 2015 D7200 has an overall Score 7 points better than the K3II. The D7200 and the D7500 are 1 - 2 steps
upward from the K3 in Image Quality, especially for the DR and ISO rating.
DxoMark Print-Mode comparison from 2010: D7k, K5 - to 2015: D7200, K3II
Better Scores expected from Higher pixel counts - Click to Enlarge
The K3-III Mono w/ an imx571 let us see the big step-up from the K3-III Bayer:
Mono: Dual Gain boosts DR, thus No Need for Destructive 2 Steps Raw-NR.
No interest to cripple a basic CMos w/ Raw-NR, too low Mono Sales Volume
Plus we do know its Dark Current level is very low vs unknown in K3 III Bayer.
But as the later 'Basic' is just a Cost-Killer to lower the High Cost of a SLR...
Bayer: 2 Stages Raw NR starting at ISO-160 as on a Q-Q10 boosts the DR,
but it kills one part of Stacking Bonus which is based on Random Noise only.
High DR Numbers'll never get the Stacking Efficiency of same CMos w/o NR: Pentax Q10 Raw-NR kills Stacking Efficiency -vs- Samsung NX mini is 5/5
Even by Multiplying the subs, the gain tends to a limit, a Glass Ceiling effect.