Forgot Password
Pentax Camera Forums Home

Showing results 1 to 25 of 300 Search:
Forum: Pentax K-1 11-25-2018, 05:26 AM  
Pentax 150-450mm + Pentax Convertor 1.4
Posted By Barry Pearson
Replies: 17
Views: 1,684
I would welcome that, and I would pre-order it now if I could!

But while I've heard rumours and wishes, I haven't seen solid evidence that it is imminent, and it isn't on the lens roadmap.

What do you know about this that I don't know?
Forum: Pentax DSLR Discussion 11-03-2018, 12:21 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
There are two separate aims, depending on the purpose of the archiving:

First, to archive the scene. This would be of use to future historians. This is rather like "photojournalism" or "wildlife" in a competition, where the winning photographer may be required to supply the original raw file so that judges can ensure that the photo is a "true representation". DNG works for this case.

Second, to archive the photographer's interpretation. This is of use to future curators of photography. The archive needs to be as close as possible to the photographer's chosen output medium. TIFF works for some cases, but in other cases prints need to be preserved.

---------- Post added 3rd Nov 2018 at 07:24 AM ----------

I think "Possibly for straight documentary shots" corresponds to part of my response to Steve.
Forum: Pentax DSLR Discussion 11-02-2018, 10:42 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
Here is a possibility that I haven't analysed much yet: The Cloud.

I've experimented with the new cloud-based Lightroom CC. (Which is different from the desktop-based Lightroom Classic CC, which is a descendent of the familiar Lightroom 6).

As I added more files on one PC, they ended up on the Adobe Cloud. They were then accessible from my other PC, and from a web browser after login at I think they were also accessible from an app on Android or iOS. (I was using DNG, but I assume this would apply to other raw formats, and it certainly works with JPEG).

They were stored on media maintained by Adobe; both the raw files and the editing metadata. (There is some tricky synchronisation involved!) So the storage medium is the responsibility of a big corporation rather than individual users. (That itself raises different questions, of course).

While the photos are on the Adobe Cloud, various added-value operations can be performed on them, such as keywording (and I think facial recognition). I assume both archiving and storage media migration will routinely be performed.

Somewhere in all of that are clues about how future-proofing might happen.
Forum: Pentax DSLR Discussion 11-02-2018, 01:56 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
This isn't about me! It is about comparing PEF with DNG.

We need a link to the specification of PEF so that we can see if it has technical advantages over DNG. (Anyone?)

We need a link to the PEF SDK so that we can examine whether PEF is easier to develop for than DNG. (Anyone?)

Are there any cases where where other camera manufacturers felt that it was better to use PEF than DNG? (Several have used DNG).

Why doesn't Ricoh use PEF for Ricoh-branded cameras? (They use DNG).

Why didn't Pentax feel the need to support PEF in the four Q-System cameras? (They used DNG).

We need links to any cases where PEF had been recommended or endorsed as an archival raw file format. (DNG has).

Why did the US Library of Congress endorsed the use of DNG rather than PEF for sustainability of their photography collections?
Re: DNG - yes or no?: Nikon FX SLR (DF, D1-D5, D600-D850) Talk Forum: Digital Photography Review

Here is a 2005 discussion about this topic:
PhotoshopNews: Photoshop News and Information Archive Digital Preservation

Here is a 2011 discussion about DNG and Digital Access Management:
Digital Asset Management Meets Adobe DNG

As far as I can tell from everything written in this thread, the primary merit that has been identified for PEF compared with DNG is that some people simply prefer using PEF!
Forum: Pentax DSLR Discussion 11-01-2018, 02:23 PM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
When I stopped counting in 2010, there were 14 cameras makers using DNG, 47 camera models using DNG, 240+ software products able to process DNG to some or a full extent, and 290+ Adobe-Convertible raw image formats. And about 7 or 8 alternative DNG converters to cater for niche or hacked cameras that the Adobe DNG Converter didn't cater for.

DNG has made it easier for niche and minority camera makers to output raw files and get their raw files processed.

Suppose that you were developing a digiscope that can record raw files. You need a raw file format to write. You needed raw file converters to process those raw files. What do you do?

Answer (and it has been done): use DNG. The format is published and freely available. There is an SDK to help develop the DNG code. Once completed, there are perhaps 100 or more software products that can now process your images.

There are many other niche and minority cameras that have benefited in the same way. Life became easier for those camera makers and users.

DNG is unlike any other raw file format.It is the only one with a freely available specification. It is the only one with a freely available (no questions asked and no NDA) SDK comprising C++ and executables. There are various other aids for using it too:
Digital Negative (DNG), Adobe DNG Converter | Adobe Photoshop CC

There is a weird attitude that some people have towards DNG. It is fairly common for people to say "DNG has problem X, so I'll continue using my ... [CR2s] ... [NEFs] ... [PEFs] ... ". Yet those raw file formats not only also suffer from problem X, but also lots more problems. Somehow, their anti-DNG (or perhaps anti-Adobe) attitude is so strong that they think a problem X with DNG (even if it exists) is vastly more serious than the same problem X and lots more with their own camera makers' non-DNG raw files.

Another common trap that people fall into is that because the format of DNG is specified they can see things that they think (rightly or wrongly) are problems. But because the format of their own camera makers' non-DNG raw files are not published, they can't see what problems are lurking there, so they appear to assume there aren't any!

Some people have criticised DNG for allowing data of unpublished format to be output as DNGPrivateData in the file. While ignoring the fact that everything in their own camera makers' non-DNG raw files is in unpublished format! It is hard to find faults with DNG that are not present (along with many more) in camera makers non-DNG raw files.

DNG is the only archival raw file format

Endorsements for DNG

How many other raw file formats are used by cameras of several different manufacturers? And why not? (As far as I know, DNG is the only raw file format for which explicit permission has been published for everyone and all organisations to use it).
Forum: Pentax DSLR Discussion 11-01-2018, 12:28 PM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
I deleted PEFs until I started to use DNGs in-camera. Then there were no longer any PEFs to be deleted!. That happened perhaps a decade or so ago.

It should be obvious that I am not, and never have been, anxious! I have never had a reason to be anxious, once I established that PEFs were irrelevant and useless to me.
Forum: Pentax DSLR Discussion 11-01-2018, 07:31 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
Having worked as an engineer in the IT industry, I beleieve there is a hierarchy of technical decision-making in Pentax:

Higher-up, there is a decision about what raw file formats are available for Pentax cameras to use. For a long time this was something like "always use DNG, optionally use PEF". We can deduce that from the raw file formats that new Pentax cameras actually used over many years. What we can't deduce is whether that decision has now changed. The last DNG-only camera I know of was announced in 2014. There have only been 6 Pentax cameras announced since then).

Below that higher-level there is a specific decision made for every camera. Perhaps the higher level policy has now changed to "DNG and PEF", or perhaps it is just an accident of history that we haven't seen any more DNG-only cameras since 2014.

Then at the lowest level there are people setting the defaults in the camera. The defaults are somewhat arbitrary. When I get a new camera I go through the menu setting the camera as I want it. I don't take the defaults seriously, because they tend to be chosen by people who don't do photography the way I do. In both the K-1ii and the K-3ii there doesn't appear to be any preference in the operating manual for one or the other. I can't remember which way they were set by default, and I don't care because they are set to DNG now!

It wasn't camera manufacturers who put pressure on Adobe. It was users. I was a user of DNG from 10 days after it was launched at the end of September 2004. The concern of a number of us was that, while the Adobe software at the time didn't need the Makernote which the DNG Converter had used to generate the DNG Metadata, things may change in future. Perhaps a later DNG Converter could exploit more the Makernote? Perhaps software other than that from Adobe could exploit some of the "secret auce"? (The DNG Converter can read a DNG, of course, so a thought was that if the Makernote was preserved, it could be further exploited by the latest DNG Converter).

I kept my PEFs until I was confident that they had been converted properly, and especially until the Makernote was preserved as DNGPrivateData. I was able to reconvert where relevant. Then I deleted all my PEFs. From that point on, (in 2005, about 6 months or so after I started to use DNG), after checking that a batch of conversions had worked, I had the confidence to delete my PEFs. That never caused me a problem.

Which camera manufacturers would be concerned and have sufficient influence to cause Adobe to provide DNGPrivateData? Obviously not those who had their own raw file formats and their own software to process them. Canon and Nikon hadn't made a decision use DNG in-camera and supply software that could process DNG and exploit any "secret sauce" their cameras might have put there. DNG was at best irrelevant to them, and at worst an irritant to be suppressed.

Leica was the first rumoured camera maker to use DNG in-camera, and one of the first to do so. I believe they packaged Photoshop Elements with their first cameras to use DNG. And Photoshop Elements didn't exploit any "secret sauce"in DNGs. Like other Adobe software processing DNGs, it uses the published DNG metadata. So Leica had no reason to put pressure on Adobe.

Ricoh's GR series was the first compact camera to use DNG, and in fact Ricoh exploit DNG more than most. They use DNG in order to use the lens-correction opcodes. (The K-1-series "only" uses DNG

It is worth noting that, when I stopped counting in 2010, there were 14 cameras makers using DNG, 47 camera models using DNG, 240+ software products able to process DNG to some or a full extent, and 290+ Adobe-Convertible raw image formats. And about 7 or 8 alternative DNG converters to cater for niche or hacked cameras that the Adobe DNG Converter didn't cater for.

For comparison, during the first 5 years when about 38 camera models were launched that wrote DNG, Adobe software added support for about 21 Canon models, about 20 Nikon models, and about 22 Olympus models.

That says more about those raw converters than about DNG! DNG is comprehensive. It caters for more capability than a typical camera uses. After all, Adobe software manages with just the published DNG specification features of DNG, so it can be done.

I take the converse view. PEF is irrelevant to me, so the fact that my Q-Series cameras didn't use PEF wasn't an issue to me. All I ask from a Pentax camera is "please use DNG; it doesn't matter whether you support PEF".


I can take a K-1ii DNG which I've used in Lightroom, put it onto an SD Card, put it back into the K-1ii, and view it. In fact, a minute before I wrote this I did precisely this! It has not been changed by Lightroom. (I've also just used the DNG SDK to examine the DNG file and verify this).

I suspect you are talking about using Lightroom to store the catalogued metadata editting back into the DNG. Rather than say, storing it as an XMP file, or simply using the Lightroom catalogue and not interfere with the DNG. I don't do that.

I don't let my DNGs get changed by Lightroom. But PEFs can also be changed by software! To the best of my knowledge, there is no way of detecting whether a PEF has been changed since it left the camera.

---------- Post added 1st Nov 2018 at 02:41 PM ----------


See my experience at the address below:
Support via DNG but not native raws

I one found that Phase One Capture One wouldn't support DNGs derived in any way from rival digital backs. So I used a hex-editor to change the camera/back name in the DNG to a same-size meaningless string of letters, and the software then worked!

It deliberately checked for, and rejected, DNGs that had the names of rivals in them!

---------- Post added 1st Nov 2018 at 02:47 PM ----------

When I stopped counting in 2010, there were 14 cameras makers using DNG, 47 camera models using DNG, 240+ software products able to process DNG to some or a full extent, and 290+ Adobe-Convertible raw image formats. And about 7 or 8 alternative DNG converters to cater for niche or hacked cameras that the Adobe DNG Converter didn't cater for.

Products that support DNG in some way
Forum: Pentax DSLR Discussion 10-30-2018, 08:50 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
My aim isn't to change what you do. I'm trying to establish some facts that will stand up to scrutiny.

I believe the following is true:
From when Pentax began to use DNG in cameras, they have continued to support DNG in all subsequent cameras that support raw
But the converse does not apply. There have been a number of Pentax cameras that support DNG but not PEF.
Not the major K-Mount cameras, but some nevertheless: Q-Series; K-500 (?); K-30 (?); MX-1 (?). Perhaps others.

Edit: Whoops! I've just that "Not a Number" was there before me!

My interpretation is that DNG is now the Pentax main and consistent raw file format, and PEF is an optional extra for historical purposes.
(Ricoh uses DNG, not its own raw file format if they ever had one, for its own cameras that support raw. Such as the GR II, and I'm confident for the GR III next year).

When Adobe software handles a DNG from out of a camera, it uses the published DNG metadata in the file, but not any "secret sauce" that is not in the DNG specification.
(What actually happened is that Adobe identified what it needed to do its raw conversions, and designed the DNG metadata to match!)
I believe the DNG format has never been influenced by the needs of a Pentax camera. Those cameras have used DNG "as-is".
(I believe this leaves something to be desired when Pixel-Shift is used. But that appears to apply whether Adobe is processing a PEF or a DNG).

I accept that there is probably some non-Adobe software that supports PEFs (once they have reversed engineered them) but not DNG.
At one time this was typically because they had already done much of the work to support PEFs, and avoided the extra generic work to support DNGs for any cameras.
I'm not sure what reasons they give nowadays.

Something interesting about DNG is the amount of material available free with no questions asked and no Non-Disclosure Agreements.
Obviously the DNG specifications!
But also the DNG SDK. It comes with both executable programs and lots of C++ files. I often use it to have a peek inside out-of-camera DNGs, hence the DNGs from my own Pentax cameras and also the Ricoh GR II.

I've been using DNG for over 14 years. I've published a huge amount about it:
DNG - Digital Negative format
DNG Barry's blog
In the unlikely event you feel the need to read it, I would welcome being informed of any errors you find.

---------- Post added 30th Oct 2018 at 04:05 PM ----------

Adobe offered DNG to ISO years ago. ISO TC42 WG18 were expected to publish it as an ISO standard. It would then not belong to Adobe in any sense.
For some reason, (my contacts won't say why), this process appears to have stalled.

Adobe did the same with TIFF, (which they "own"). Unfortunately ISO mangled it to become TIFF/EP, which was not prescriptive enough to be useful for interchange. It ended up more as a kit of optional parts.
(DNG and NEF are both based on TIFF/EP. DNG was Adobe's proposal to ISO to make TIFF/EP a more useful standard).

(Adobe also supplied PDF to ISO. It is now, I think, 3 ISO standards, and Adobe don't own it. I think ISO have also taken over XMP, as they presumably needed to for PDF purposes).

---------- Post added 30th Oct 2018 at 04:16 PM ----------

I've haven't time to check, but here is my guess:

The DNG Converter puts XMP into the DNG to record what it has done.
Probably the camera simply can't handle the XMP. After all, it is not needed by the camera and doesn't put it in the DNG.
If that is the reason, I don't know why the camera can't ignore it.

There are other possibilities.
Perhaps Pentax cameras write using a subset of DNG, for example with the image data stored in a particular way. But the DNG Converter (legitimately according to the specification) happens to use a different structure.

In other words, there is no need for a camera to implement the full generality of DNG, because it never expects to encounter it.
Forum: Pentax DSLR Discussion 10-29-2018, 07:52 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
It is important to distinguish between the generic raw file format such as "PEF", and the specific raw file format such as "PEF from K-1".

The former doesn't pose much of a problem. It is the latter that can cause problems, as your example "support for new camera raw formats within months of their release, open-source software within weeks or even days" indicates.

There will be "PEFs from K-1s" around. Will they be sufficient to decide how to perform high quality raw conversions in the new software, without being able to test by experimenting with a camera?

It may be worth noting the vast number of ways that cameras differ from one-another:
DNG and camera innovation

Perhaps it will be possible by using (say) dcraw. After all, Dave Coffin decided to re-design dcraw to conform to some aspects of DNG. So now some features of DNG, including some DNG metadata values for a large range of cameras, are openly available. So in future software will be able to benefit from DNG metadata when processing non-DNG raw files for cameras supported by dcraw. Perhaps in future many people will use PEF in-camera and (perhaps unknowingly) end up with a raw conversion that relies on DNG metadata values.
Forum: Pentax DSLR Discussion 10-29-2018, 06:42 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
A PEF doesn't fully describe the image. That is why software that supports PEFs from existing cameras has to be updated to support PEFs from new cameras. The software developer has to learn about the extra details that the PEF doesn't hold, and build that into the software.

How are future software developers going to discover what those necessary extra details are that are needed for raw conversions? They may not be able to play around with existing cameras to reverse-engineer those details.

A DNG holds those details in extra metadata that enables software to perform a high-quality raw conversion on a new camera without having to build in extra details for that camera. A huge amount and variety of such details is catered for by DNG. That is why there have so far been just 5 versions of DNG in over 14 years. ( to And even the K-1-series only needs and outputs!

(The current Ricoh GR series uses version because it uses lens-correction opcodes which were introduced in that version).
Forum: Pentax DSLR Discussion 10-29-2018, 05:53 AM  
RAW file format
Posted By Barry Pearson
Replies: 57
Views: 4,527
At one time, Pentax cameras didn't use the DNG compression option.

I can't remember which was the first Pentax camera to use the DNG compression option.
Forum: Pentax DSLR Discussion 10-07-2018, 04:16 AM  
Considering Full-spectrum Conversion
Posted By Barry Pearson
Replies: 6
Views: 1,345
As a result of this thread, I'm considering having my K-3 (superseded by my K-3ii) converted for Full Spectrum. Being superseded, I will not want to use it for visible-light photography.

I have a Hoya Infrared R72 which would appear to be useful on such a camera for IR photography.

But what filters would be useful for UV photography?

The B+W 77mm UV Black (403) Filter has been discontinued.
Forum: Digital Processing, Software, and Printing 10-06-2018, 03:20 AM  
Cloud backup for raw files
Posted By Barry Pearson
Replies: 11
Views: 994

It can be synchronised into Lightroom Classic CC, or its desktop-oriented predecessors such as Lightroom 6.

And it is a fundamental feature of Lightroom CC, the newer cloud-based variant of Lightroom.
Forum: Digital Processing, Software, and Printing 10-06-2018, 12:31 AM  
Using Exiftool and Excel to analyse my images
Posted By Barry Pearson
Replies: 5
Views: 792
That is what I use - a lot!

I like it because it doesn't simply provide the numbers. It displays a grid of the photos concerned.
Forum: Digital Processing, Software, and Printing 10-05-2018, 03:14 AM  
PEF & Lightroom - HELP
Posted By Barry Pearson
Replies: 6
Views: 1,155
It will recognise PEFs for cameras released until Adobe stopped updating Lightroom 6.

PEFs have an overall consistent specification, but have detailed differences from one camera to another.

The specification for DNG rarely changes, because of its large amount of metadata which can cater for a huge range of detailed differences. Lightroom 6 recognises DNGs from all current Pentax cameras, and in fact recognises even later versions of DNG that haven't been used by Pentax cameras yet. (With the qualification that it hasn't caught up with pixel-shift technology yet).
Forum: Digital Processing, Software, and Printing 10-05-2018, 12:50 AM  
PEF & Lightroom - HELP
Posted By Barry Pearson
Replies: 6
Views: 1,155
It isn't too late!

Download and install Lightroom 6 (Single App license)

"Last Published: June 27, 2018"
Forum: Pentax SLR Lens Discussion 09-28-2018, 05:06 AM  
24-70 alternative lens for K1
Posted By Barry Pearson
Replies: 43
Views: 4,190
You say you have noted the 28-105mm kit lens. What were you conclusions?

It isn't limited in image quality to what used to be called a "kit lens". It is very good indeed across the frame and at all settings. Often it is the only lens I use all day on my K-1-series, and I read of others who think the same.
Forum: Pentax DSLR Discussion 09-26-2018, 08:02 AM  
Bought K-1 II, Sold K-3 ii--have DA lenses--buy used APS-C as back-up?
Posted By Barry Pearson
Replies: 41
Views: 2,930
Hm! I use my K-3ii as my back-up for my K-1ii.

You appear to have ruled that out.
Forum: Troubleshooting and Beginner Help 09-13-2018, 11:22 PM  
Crop mode on K-1
Posted By Barry Pearson
Replies: 37
Views: 1,936
Others have answer your basic question. I'll add something that I haven't spotted here.

The K-1-series also has "Square" crop mode. About 24 MP. All it really gives you is a visual indication in the viewfinder, which some people may find useful, while others don't.

I discussed it at the DPReview thread below. (Including how to recover images back to 36 MP in Lightroom).

Revisiting SQUARE crop on K-1-series
Forum: Photographic Industry and Professionals 09-06-2018, 12:27 AM  
So glad Pentax isn't making a mirrorless now!
Posted By Barry Pearson
Replies: 69
Views: 4,739
I haven't gone away!

I have all the recent Pentax FF lenses, and with the right Pentax mirrorless camera, plus the K-mount adapter that Pentax would supply (unless they had a death-wish), I would buy such a camera.

(It would co-exist with my K-1ii, hopefully complementing it rather than competing with it or replacing it).
Forum: Troubleshooting and Beginner Help 09-04-2018, 11:39 PM  
Correcting a shot that isn't level.
Posted By Barry Pearson
Replies: 18
Views: 1,270
When I'm cropping in Lightroom (Classic CC), I often also use the "Transform" panel in the Develop module.

The transformations can be done while the crop rectangle is still visible. This means some quite tricky alignment and perspective problems can be mitigated.

So I might (for example) make two or more of the things that are vertical in real life vertical and parallel in the image. A building and a lamp-post, for example.

(If I'm ambitious, I might vary the horizontals as well! But that can introduce some unwanted distortions).
Forum: Pentax Full Frame 09-03-2018, 05:54 AM  
Is Pentax in the need of a M/L system?
Posted By Barry Pearson
Replies: 160
Views: 9,162
The adapter would be a way of saving me lots of money if I decide I could benefit from such a camera from Ricoh/Pentax.

It would be an optional purchase that I would want to make.
Forum: Pentax Full Frame 09-03-2018, 03:19 AM  
Is Pentax in the need of a M/L system?
Posted By Barry Pearson
Replies: 160
Views: 9,162
I responded to establish the fact that introducing a new mount and system does not have to risk losing existing users of that maker's cameras and lenses.

Neither of us is able to say what proportion of existing Nikon (or Canon) users will buy their adapters.

Perhaps we will see some statistics in (say) a year or so.

(I have a Q System with 2 cameras, 4 lenses, and the K-mount to Q-mount adapter. If Pentax released a new mount suitable for larger sensors such as FF, and I found one or more of the new mirrorless cameras was good for me, I would buy such an adapter).
Forum: Pentax Full Frame 09-03-2018, 12:21 AM  
Is Pentax in the need of a M/L system?
Posted By Barry Pearson
Replies: 160
Views: 9,162
The new Canon and Nikon mirrorless systems have (apparently fully functional) adapters to mount their existing SLR lenses. A user only needs to buy 1 adapter.

This means that these new cameras can be used a stand-alone new cameras, or as complements to existing cameras from those companies. Both the companies and their users can make the transition at their own pace. If users even choose to make the transition at all.

If Ricoh/Pentax provided a mirrorless mount & cameras, I would expect them to provide a suitable adapter. (If they didn't, they would indeed alienate existing users).
Forum: General Photography 08-14-2018, 07:30 PM  
How to take photo's for wide resolution? (e.g 3:1)
Posted By Barry Pearson
Replies: 8
Views: 676
Those images are tiny compared with the number of pixels in any Pentax camera.

It is possible to (say) take a photo where the subject only fills about a quarter of the frame, then crop in post-processing and downsize dramatically to those image sizes, with results that should be very sharp if the image was captured properly.

If the image is captured, with plenty of cropping space, as well as any Pentax camera can do, this sounds like a problem in post-processing.

But ... trying to use an 851 x 315 image as a banner will look bad on any decent sized screen. For example, the screen I'm using at the moment is 2560 pixels wide. If the image gets upsized to fit, it will look unsharp.
Search took 0.02 seconds | Showing results 1 to 25 of 300

Forum Jump

All times are GMT -7. The time now is 01:45 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]