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Forum: Digital Processing, Software, and Printing 1 Day Ago  
Fixing Adobe's problem with maps in LR 5 and LR 6
Posted By beholder3
Replies: 3
Views: 218
Since Adobe seems to try to grab a lot of money from users but not fix their self caused problems, some users have worked on the issue that LR 5 and 6 map functionality is still broken.

GitHub - astuder/lightroom-map-fix: Fixing the Map module in Lightroom Classic

This is not for noobs.

The better free map module replacements are GeoSetter (Description - GeoSetter), which can use OpenStreetmaps and darktable (darktable).
Forum: Pentax News and Rumors 1 Day Ago  
Nippon Camera Ricoh/Pentax 2019 Interview
Posted By beholder3
Replies: 800
Views: 33,311
A current Canon DPAF sensor still has leagues better dynamic range than a Sony/Nikon rebadged D5 sensor. It is all not so easy.

---------- Post added 20th Jan 2019 at 09:08 ----------



Since a number of recent Samsung smartphones use Sony sensors with DPAF (Samsung's Galaxy S7 Phone is the First with Dual Pixel Auto Focus) I do not believe it is a patent limitation.
Forum: Photographic Industry and Professionals 1 Day Ago  
Ricoh 3.1% Consumer Electronics Market Share in Japan
Posted By beholder3
Replies: 33
Views: 1,704
Based on the historical data shown above I am confident the market for old school combustion engine cars will go away before the same happens for DSLR as subtype of ILC.

I guess the more pressing thing is that ILC as whole dinosaur (with or without mirror is no difference) is still being pushed aside by cameras in smartphones and the latter are innovating much faster than the likes of Fuji, Sony, Nikon, Canon, Pentax ever will.
Forum: Photographic Industry and Professionals 3 Days Ago  
Ricoh 3.1% Consumer Electronics Market Share in Japan
Posted By beholder3
Replies: 33
Views: 1,704
The most up to date chart for CIPA sales: including Nov 2018.

Usually December, January, February are the hardest months for makers.




Forum: Photographic Industry and Professionals 4 Days Ago  
Ricoh 3.1% Consumer Electronics Market Share in Japan
Posted By beholder3
Replies: 33
Views: 1,704
Many here seem to not understand that discontinueing the k500 and ks1 entry level lines has exactly the effect to sell much fewer units as reported here.

Pentax did intentionally drop the Rebel segment.

Anyone asking for a higher unit share asks for a k600.

A drop in share is only clearly bad if the product portfolio is comparable.
Forum: General Photography 01-13-2019, 09:57 AM  
Mirrorless cameras and sensors - the good, the bad and the really ugly
Posted By beholder3
Replies: 32
Views: 1,001
This here is a quite good example of what we are talking about (even if old news):
Noise comparison between hot and cold sensor (long exposure): Micro Four Thirds Talk Forum: Digital Photography Review
The decrease of image quality in the mirrorless camera after just 10 minutes of video usage and heating the sensor is quite obvious.

Another interesting bit is that Canon even explicitly seems to warn about image degradation after longer liveview shooting:
dslr - Do mirrorless cameras have more sensor noise because they are constantly exposed to light? - Photography Stack Exchange

And here I found a very good graph showing how different the sensor noise for long exposures can grow:
Length of Exposure vs Sensor Temp. - DSLR & Digital Camera Astro Imaging & Processing - Cloudy Nights
At the end of the thread there is a similar measurement to the one I have done, there with a Nikon D5100 doing long exposures.

and here are some interesting evaluations:
https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=10773
(old tiny sensors, but still interesting)
Forum: General Photography 01-13-2019, 04:00 AM  
Mirrorless cameras and sensors - the good, the bad and the really ugly
Posted By beholder3
Replies: 32
Views: 1,001
^^This.

If you follow the links already provided in above threads you'll see that Jim Kasson has clearly identified Sony noise reduction massaging raw files: The Sony a7RIII eats stars
Sony manipulates raw files at least from ISO 1000 (probably even at lower ISO) by "spatial filtering".
And Jim Kasson is rather a Sony fan than somebody being too critical.


Bill Claff's page simply turns a blind eye (as discussed elsewhere, his whole approach is highly questionable in many other ways as well).
Forum: General Photography 01-13-2019, 02:09 AM  
Mirrorless cameras and sensors - the good, the bad and the really ugly
Posted By beholder3
Replies: 32
Views: 1,001
I bet you understand that the subjective bit here is, what is "fringe conditions".
I could argue that the vast majority of photographers uses smartphones and considers all scenarios where a ILC is preferable "fringe conditions". And that would be a sound quantitatively based assumption.

Within the minority group ILC usage class again it is open to debate which items are "fringe conditions". I could argue that all shooting scenarios where the dynamic range differences between a K-7 and a K-1 are important are "fringe conditions". And just the same any shooting scenarios where today noobs complain about improved automation helpers (autofocus, green mode etc) are "fringe conditions" as for vast majority user groups they do not pose any problem.
Since all caneras today are so well rounded I guess all negative findings are for "fringe conditions".

I see only two scientifically sound ways to approach this:
  1. we describe the issues as any general problem plus we describe the caveat : the exact parameters under which they appear and where it will not. Here the burden of evaluation is still on the reader to judge relevancy.
    It is like all "resolution" discussions on forums. I guess only a tiny minority really understands how seldom they'll ever recognize differences between real life images.

  2. (preferred for most levels of readers) we first define a realistic usage pattern in detail (some users who shoot wildlife day in and day out could discuss and describe their usage) and the "test" / "measurement" then tries to emulate the scenario. The findings obviously then only are valid for this usage pattern. Wildlife sensor heatup is not the same as sensor heatup for users who already complain that they have to push the button again after 30 min of non-stop video recording.

Forum: General Photography 01-12-2019, 01:33 PM  
Mirrorless cameras and sensors - the good, the bad and the really ugly
Posted By beholder3
Replies: 32
Views: 1,001
It is casual holiday snapshots versus well composed shots or those for which you need to watch / follow / track the subject for a prolonged time (e.g. any wildlife, birding, sports). In the latter cases you will keep your eyes at the viewfinder for a long time per shot or series of shots.
This will require the DSLM to keep the sensor busy all the time and for long times.

If you just raise the camera to the eye every hour and then quickly take a shot that will not impact sensor temperatures in any ILC.

If I was a wildlife shooter and spending a lot of time checking the viewfinder at anyhow higher ISOs I'd be worried though about the impact of heat induced noise.
Forum: Pentax News and Rumors 01-12-2019, 03:08 AM  
Nippon Camera Ricoh/Pentax 2019 Interview
Posted By beholder3
Replies: 800
Views: 33,311
The Laowa 12mm F2.8 is fast ultrawide glass for FF and it is "small" (but heavy due to top level metal contruction and a lot of glass inside).

If you can somehow transform Laowas design logic into a 20mm F4 (both the longer focal length and then smaller aperture should make it possible to make the lens even smaller), then this would be nice.
Forum: General Photography 01-12-2019, 02:03 AM  
Mirrorless cameras and sensors - the good, the bad and the really ugly
Posted By beholder3
Replies: 32
Views: 1,001
I don't think I have the exact environmental temperature data recorded. I think it was around 23 °C. I did quite some playing around before I did these recordings, so the camera body and sensors were already heated up to the levels shown.
I would expect that the increments will be even higher in the beginning if you start off in cool state.

Since I did measure the temperature with an IR camera it all was with lens off. I'd expect the more limited air circulation with a lens to cause even steeper increases.

---------- Post added 12th Jan 2019 at 10:19 ----------

Here is also more thorough information on Sony's star eater problem:

Star Eater: Documentation of an Issue with the Sony Cameras for Astrophotography (and How to Fix It) – Lonely Speck

and

Sony Star Eater






QuoteQuote:

The “Star Eater” problem is a form of software spatial filtering designed to reduce noise in photos, particularly hot pixels. Unfortunately, the rather rudimentary filtering algorithm that Sony is using easily mistakes sharp pinpoint stars for noise, nearly deleting them from the image or greatly reducing their brightness. The result is an astrophoto with less stars and the appearance of diminished resolution. Sony a7RII, a7SII and a7RIII cameras exhibit this problem for all exposure times longer than 3.2″.



and it was only partially fixed in firmware:






QuoteQuote:

The improvement to the "Star Eater" spatial filtering algorithm was made in firmware v4.0 for the Sony A7RII. It is believed it was also implemented in firmware v3.0 for the Sony A7SII but I haven't yet seen any proof.The improvement makes a difference only for the green pixels. The blue and red pixels are affected just as badly as previously. The effect is that more stars survive than previously but these "new" survivors are predominately green in colour.



One of the main weaknesses of consumer directed simplisitic websites such as DXomark and BClaff's blog pages are the poor documentation of the limitations of the chosen analysis/test setup, making them so untrustworthy.
In this case: Both completely close their eyes to / ignore poor camera performance in normal bulb mode for long term exposures.
If you look at their SNR curves, you'll find not even a hint at the massive raw data massaging going on at all ISO levels for long exposures.
Forum: Photographic Industry and Professionals 01-11-2019, 11:45 AM  
Canon starting to butcher Sony in FF mirrorless (as predicted)
Posted By beholder3
Replies: 54
Views: 2,706
In a month or so we'll see the quarterly figures from Sony, Nikon, Canon. They will be telling a story.
And latest in springtime one quarter later we will see how it all plays out.

The whole ILC market is still shrinking and I would be surprised to hear that more people buy the new (quite overpriced) toys from these three makers than those who either wait a year or two to see how it all develops or those who own Canon/Nikon DSLRs and simply stop investing for now.

I guess down, down, down is where it is going.
Forum: Pentax News and Rumors 01-11-2019, 11:32 AM  
Nippon Camera Ricoh/Pentax 2019 Interview
Posted By beholder3
Replies: 800
Views: 33,311
A slow 1.8 version 85mm only, which is worth $450 new and will probably get to the market for $1000. :lol:
And I bet it will weight twice as much than the 350g DSLR lens, which itself is already a fat piece of glass compared to the 77mm princess.
Forum: General Photography 01-11-2019, 11:25 AM  
Mirrorless cameras and sensors - the good, the bad and the really ugly
Posted By beholder3
Replies: 32
Views: 1,001
This thread intends to spend a little time to analyze the many issues with sensors for mirrorless cameras and which problems and issues they suffer from - beyond typical DSLR sensor attributes.

Lets start with a discussion about inevitable sensor heat up and following image quality decrease through image noise increase.

Indeed, at least some earlier Sony models were known for not supporting extended video recording as they would shut down due to sensor overheating.

It is documented (The new Sony a7RIII camera still eats stars - Photo Rumors) that even the latest Sonys do eat stars due to their (it seems) constant noise reduction. You could call the Sony behaviour as "accelerator on steroids" as it obviously works all the time and not only from ISO 640 onwards.






QuoteQuote:

The smaller body design/size of the Sony A7RIII (and other A series cameras) results in a higher internal camera heat level which means in general a more aggressive noise reduction is necessary across the ISO range, but particularly important in the high ISO range and during long exposures because the accumulated effect of the activated sensor causes the heat to skew the signal/noise ratio and produces much noisier images. This is much more evident in higher resolution cameras like the A7R II & III because the more intense data processing generates more heat and the electronics of a higher resolution sensor means more dark noise in the signal/noise ratio. In order to resolve that a more aggressive noise reduction had to be applied at ISOs > 3200 which causes pixel level stars to be wiped. Pixel level doesn't mean actual pixel sized stars, the threshold is actually 4 pixels that make up an RGB block of the Bayer array since color info is needed to make noise reduction adjustment, so stars that are ~4 pixels or smaller are at risk of getting removed.
The phase detect AF sensors built into the imaging sensor generate dark noise in the sensor readout, and that is also especially noticeable at ISOs >3200. In addition, even though the PDAF system is not active during the actual capture of a photo, the electronics are passively in a "standby" mode and that generates additional dark noise. Because of this, the PDAF hot spot areas follow a noise reduction algorithm that is different than the rest of the sensor and accounts for that in order to deliver a smooth gradation and even noise pattern.
I was also told that currently because of the hardware limitations there is no way to resolve the issue and that it is not technically an issue at all, it is just a limitation of the hardware. Any fixes that would be applied via firmware would end up exposing the higher noise, which the engineering team determined would be a worse problem for users so it doesn't seem like a proper solution is in the works.



This does explain the suprisingly much inferior level of details you get to see from Sony cameras like the A7R3 when compared to Pentax and Nikon DSLR.

The Sony video overheating issue is still ongoing:
  1. SONY a7 III a73 OVERHEATING issue: Sony Alpha Full Frame E-mount Talk Forum: Digital Photography Review

  2. A7R III Overheat Issue: Sony Alpha Full Frame E-mount Talk Forum: Digital Photography Review

It seems there is no solution available even after years and many model changes.

I dont want to see full res Sony image noise under demanding low light long exposure settings after using video. You probably have to not use the camera for 15 minutes at least before you get back average noise /dynamic range performance from a glowing sensor.

I once measured a K-3 II and I wonder if someone has similar data available from a APSC or FF mirrorless camera.





You just need a camera, some time and an infrared camera to measure the sensor.

Maybe even metadata in the images documents temperature (often with 3rd party cameras it is body temperature thoughm which is much lower than sensor temperature).
Forum: Pentax Camera and Field Accessories 01-11-2019, 10:59 AM  
Battery cross compatibility - Pentax D-LI90 and Panasonic BLF19
Posted By beholder3
Replies: 7
Views: 1,373
It is likely the D-LI90 just contains two type 18500 batteries like this 3rd party copy: http://h2097500.stratoserver.net/forumimages/2019/1681/1681_2019010542_bater...psa504f47d.jpg

Lithium ion batteries usually first have two contacts for plus and minus.
The third contact often is a thermo resistor as a safety measure.
More contacts usually are for more advanced protection mechanisms.

There are many cases where cheap 3rd party copy batteries seem to have contacts for thermo resistors or other protection mechanisms but actually are "blind" with nothing behind them.
Unless you open them or have the capability and knowledge to check them this is a health risk.
I do stay away from 3rd party batteries.
Forum: Pentax News and Rumors 01-09-2019, 11:44 AM  
Development update regarding the HD PENTAX-D FA★50mmF1.4 SDM AW
Posted By beholder3
Replies: 720
Views: 52,047
Overall any lens completely failing the autofocus department always looses against any other lens.
No second thoughts there.

The Otus sucks with regards to vignetting and resulting bokeh even against the Sigma, which is worse than the Pentax.
See digital-picture website.
Forum: Pentax DSLR Discussion 01-09-2019, 10:20 AM  
Resurrecting Pentax firmware hacking
Posted By beholder3
Replies: 747
Views: 232,689
The first link in this thread: Datenbank für Lensroms / eeprom / Lenseep ? Pentaxians shows a link to a dropbox.
Forum: Pentax K-1 01-07-2019, 03:13 AM  
Photo District News puts K-1 at #6 for color reproduction.
Posted By beholder3
Replies: 12
Views: 1,238
As a matter of fact (at least for Pentax) the cameras do not struggle from hardware side. The developers creating the camera profiles struggle.

I checked a number of my images where in Lightroom the red colors appeared oversaturated and burnt out.

The raw showed two things:
  1. The reds were fine in raw data

  2. Actually the two green channels were 0.5 to 1 stop closer to burning out than red.

So poor .dcp color profiles were the main issue.
Forum: Pentax K-1 01-07-2019, 02:56 AM  
Photo District News puts K-1 at #6 for color reproduction.
Posted By beholder3
Replies: 12
Views: 1,238
Instead of taking home the message that the Nikon Z7 can't compete with even with a compact camera in this area (tabloids might write "second worst color reproduction camera of the year" :lol:) there is one little interesting bit in the otherwise worthless result presentation:

They ALL fail miserably with the reds.
Forum: Pentax DSLR Discussion 01-07-2019, 02:23 AM  
Resurrecting Pentax firmware hacking
Posted By beholder3
Replies: 747
Views: 232,689
Some people have downloaded the lens rom settings from that lens. Maybe you take a look at those files.
Forum: Pentax K-1 01-07-2019, 01:58 AM  
Photo District News puts K-1 at #6 for color reproduction.
Posted By beholder3
Replies: 12
Views: 1,238
Sadly this is yet another poorly (really, really poorly) documented "test".

Obviously "color" can only be judged in JPG / TIFF or similar, not raw files. So some "recipes" have to be applied. In camera the recipes are the color modes plus white balancing. In raw converters you have the camera color profiles (e.g. .dcp files) which apply base curves, contrast, saturation etc.

Completely undocumented which settings they used.

Even the pdf on test methodology leaves it completely open.


From a color science perspective we need to know the exact illuminant used and the color recipes / color modes used in camera.

As it stands they could have used 3000K WB and "bleach bypass" color mode on any random camera.

And how do you pick the right JPG color mode in the camera? They all have a dozen. Just use the default one that comes up?

Any user who really cares about color would never use JPG straight ooC and even worse: the default color mode and even worse: the default color mode without any adjustments.
That is behaviour like you get it from mobile phone users.
Forum: Pentax DSLR Discussion 01-06-2019, 04:15 AM  
AF-sensors: powerful little things
Posted By beholder3
Replies: 2
Views: 908
I guess most people discussing AF never really appreciate what the little things do and under which circumstances they perform.

Each AF line sensor actually requires two short pixel lines (sometimes double pixels), very much like a short row of single (or two) pixels from the main sensor.

Each of these has to watch the subject through its own optics at the outer part of the image circle of the lens, typically placed where the edge of the aperture blades appear at F5.6.

They only work if they can see the whole framed image in pretty much complete sharpness (maximum DoF), since they do need to compare tiny detail of the frame while the users might see only blur in the viewfinder.

So the image (remember it is not really an image as we know, it is just a single pixel row "crop") is very small and (as I recently read) works as f/30 aperture.

No go combine this with our needs to have fast AF, and let us assume we want the AF to check the image every 1/10th of a second. Obviously this means the "shutter time" plus readout and computation can not be longer than 1/10 of a second.

And now go figure what "ISO" your little sensor row needs to operate at to focus in a scene where the ambient light is only EV 3.
That is roundabout ISO 102.400 at EV 3 already.

With a focus system that works down to EV -3, this requires the AF sensor to work at something like ISO 6,553,600. Obviously in reality the camera prefers to slow down readout times and prolong "shutter time" instead. But still.

Then imagine all the noise existing in that little row of pixels at that ISO, providing false image information.

And still the system needs to compare the two sensor pixel rows to find (and match) a good contrast edge. And we usually do not take images of checkerboards.

I think this is quite an engineering feat. :)
Forum: Troubleshooting and Beginner Help 01-06-2019, 02:56 AM  
K-1 SD Card write time: gets worse with time?
Posted By beholder3
Replies: 21
Views: 735
Memory cards age with wear and then they also are not completely reliable.

The fuller they get the slower they are.


Start off with completely wiping the card using the official format tool: SD Memory Card Formatter - SD Association and then check again writing to the empty card.
Forum: Pentax DSLR Discussion 01-06-2019, 02:03 AM  
Resurrecting Pentax firmware hacking
Posted By beholder3
Replies: 747
Views: 232,689
My best wishes to you to get well soon!

Health is so much more important than gadgets.
Forum: Pentax News and Rumors 01-06-2019, 02:01 AM  
Nippon Camera Ricoh/Pentax 2019 Interview
Posted By beholder3
Replies: 800
Views: 33,311
But facts show that your personal imagination of "everyone" is just a projection of your personal wishes.
In fact "everyone" expects to see other lenses.
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