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02-21-2015, 06:45 PM   #46
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I think 36MP is probably the right way for Pentax to go. Other considerations aside, it's just right from a marketing perspective. In the marketplace it clearly defines a niche between the K-3 and the Z. I can see the advantage of a 50mp sensor for those who want higher than 16MP for APS-C shooting, but given that this is provided by the K-3, or by shooting at FF with a longer focal length, I'm not sure that this is a good enough reason for going to 50MP, given the performance hit you would take, or expense to keep performance the same.

One of the disadvantages of a high resolution sensor is the size of outputted files and resultant drop in performance when handling these files in PP (yes it's not the only disadvantage I know). It should be possible to output smaller sizes while keeping most of the actual image detail by downsampling the data in-camera. This would reduce the required storage space and speed up processing times significantly. If you downsample a 36mp image to 16mp in Photoshop, it will have a lot more image detail than an equivalent image shot on a 16mp camera. I would have thought it should be possible to output this as a raw file. This type of processing would, I presume, slow down performance somewhat, so it isn't the answer to all of the issues of a high-res sensor, but would help to address some concerns. You could have a number of different sizes in fairly small steps - 28, 22, 18, 14, 10 etc.

Another thing which will help is to allow a number of different in-camera crops from the full sensor - not just the APS-C crop. This should not entail a performance hit as you are simply recording a subset of the captured data. Those that want to work with smaller, lower resolution files will simply need to take account of the crop factor when choosing focal length. This idea could also be extended to include variable aspect ratios, which I think would be great. You would need a means of showing the crop in the viewfinder of course, which may entail the introduction of an LCD overlay along the lines of Canikon. This was proposed in another thread recently but unfortunately was not discussed very much.

02-21-2015, 07:38 PM   #47
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QuoteOriginally posted by jonby Quote
Another thing which will help is to allow a number of different in-camera crops from the full sensor - not just the APS-C crop.
I suspect this is a given. Nikon D810 for example has FX @ 36mp, 1.2x crop @ 25mp and DX @ 15mp. So you have a 36mp FF with ability to give you k-3 or k-5 size images if you want. And the 1.2x crop would almost certainly work with a lot of DA lenses that almost cover FF but might not quite make it without vignetting. So a 1.2x crop gives you the equivalent of a k-3 image will continuing to use many (most?) DA lenses. And if the DA lens cannot handle a 1.2x crop then crop to 1.5x and get a k-5 equivalent image.

For something that requires fast FPS you should be able to select the lower crop mode and shoot the camera as if it were a 15mp camera but with the processing power and buffer that can handle 36mp images. That sounds quite interesting.
02-22-2015, 10:53 AM   #48
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QuoteOriginally posted by jatrax Quote
I suspect this is a given. Nikon D810 for example has FX @ 36mp, 1.2x crop @ 25mp and DX @ 15mp. So you have a 36mp FF with ability to give you k-3 or k-5 size images if you want. And the 1.2x crop would almost certainly work with a lot of DA lenses that almost cover FF but might not quite make it without vignetting. So a 1.2x crop gives you the equivalent of a k-3 image will continuing to use many (most?) DA lenses. And if the DA lens cannot handle a 1.2x crop then crop to 1.5x and get a k-5 equivalent image.
I agree with much of what you say, but I'm not sure we can automatically expect any more than the APS-C crop. Yes the D800/810s have the 1.2x crop, but the Canons don't even have the APS-C mode. Anyway, I'm suggesting that it would be useful to go a little further than the 1.2x and 5:4 crops implemented on the D800 series and include something in between the 1.2 & 1.5x crops, plus other aspect ratios such as square, 16:9 and maybe more.

One thing which makes none of these a given is how these crops will be indicated in the viewfinder. The current Pentax viewfinder implementation may dictate that crop marks are etched onto the focusing screen. With multiple crops available this is likely to mean a lot of clutter in the viewfinder. Nikon uses an LCD overlay for this which allows crop marks to be hidden, but Pentax have never used this and there is some strong opposition to them doing so amongst some Pentax Forum members.

---------- Post added 02-22-15 at 11:48 AM ----------

Also, what do you think of the in-camera resampling options I mentioned? Most cameras these days include some lower-res raw modes, but my experience with them is that they only capture information equivalent to a bayer sensor of that resolution (or less). For example, I have used the M RAW option on the Canon 6D, which is (I think) 11MP. The detail you get from this mode is only around the same as what you would get from an 11MP bayer camera (actually I would say it was a little worse). I presume this is because the camera is binning the information from every other photosite in the sensor, or something like that, rather than gathering all the information and resampling it down to a smaller sized image. In theory, it should be possible to resample down to significantly smaller image sizes in-camera to obtain a high level of per-pixel sharpness in more compact files. Apart from the extra in-camera processing time involved, there may be issues with compatibility with raw converters, but I'm not sure - Adobe DNG converter has options to downsize raw files to DNGs which open fine in ACR. I guess I'm suggesting that it might be possible to get files out of the camera which store image information more efficiently than current raw files from bayer sensors do.
02-22-2015, 02:01 PM   #49
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QuoteOriginally posted by jonby Quote
I agree with much of what you say, but I'm not sure we can automatically expect any more than the APS-C crop. Yes the D800/810s have the 1.2x crop, but the Canons don't even have the APS-C mode. Anyway, I'm suggesting that it would be useful to go a little further than the 1.2x and 5:4 crops implemented on the D800 series and include something in between the 1.2 & 1.5x crops, plus other aspect ratios such as square, 16:9 and maybe more.
No one knows until the camera shows up but with Nikon's example I don't see any reason not to think Ricoh will include such an obviously useful feature. Particuarly since they have a stable of APS-C format lenses they will need to provide a way to use correctly.
I've no problem with other crops, though I have had other cameras with different aspect ratios and crops available and never used them. Waste of time for me since I always shoot in RAW and crop/process on the computer. For others, especially jpeg shooters I can see the utility but not sure anyone would actually think "That scene would look good in a square format, wait a second while I find that in the menu and switch to square mode". If I see something that I think will end up as square I just frame it that way knowing I'll crop on the computer.

QuoteOriginally posted by jonby Quote
One thing which makes none of these a given is how these crops will be indicated in the viewfinder. The current Pentax viewfinder implementation may dictate that crop marks are etched onto the focusing screen. With multiple crops available this is likely to mean a lot of clutter in the viewfinder.
I believe there was a Pentax patent for showing information in the OVF. Not sure what information but possibly the crops? They hinted that something different was going on in the big pentaprism housing.

QuoteOriginally posted by jonby Quote
Also, what do you think of the in-camera resampling options I mentioned? Most cameras these days include some lower-res raw modes,
Possibly useful for jpeg shooters. For RAW shooters, I doubt it makes much sense. Certainly does not to me. If I'm shooting in RAW, which I am, the reason is to get the most information possible in as clean a format as possible. Down sampling or any other mucking about with the image in camera is not something I want happening. ACR and Lightroom do provide a smaller 'lossy' DNG format based on jpeg compression. But the only advantage I can see is saving storage space while retaining some of the editing headroom a RAW file has. Again, possibly useful for some but not something I would bother with.

02-22-2015, 03:37 PM   #50
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QuoteOriginally posted by jonby Quote

---------- Post added 02-22-15 at 11:48 AM ----------

[/COLOR]Also, what do you think of the in-camera resampling options I mentioned? Most cameras these days include some lower-res raw modes, but my experience with them is that they only capture information equivalent to a bayer sensor of that resolution (or less). For example, I have used the M RAW option on the Canon 6D, which is (I think) 11MP. The detail you get from this mode is only around the same as what you would get from an 11MP bayer camera (actually I would say it was a little worse). I presume this is because the camera is binning the information from every other photosite in the sensor, or something like that, rather than gathering all the information and resampling it down to a smaller sized image. In theory, it should be possible to resample down to significantly smaller image sizes in-camera to obtain a high level of per-pixel sharpness in more compact files. Apart from the extra in-camera processing time involved, there may be issues with compatibility with raw converters, but I'm not sure - Adobe DNG converter has options to downsize raw files to DNGs which open fine in ACR. I guess I'm suggesting that it might be possible to get files out of the camera which store image information more efficiently than current raw files from bayer sensors do.
I think it would be a good feature if it could be fast enough. Thing is it would basically be doing in-camera what you can easily do in something like Lightroom (which uses a 'smart' downsampling algorithm during export.)

I can see how it would be a time-saver to have very good downsampling happening in-camera with maybe DNG as an optional output format, for example. You'd have to find a way to sell the feature as distinct from simpler down-res, though, and I'm not sure if Pentax marketing would be confident they could do that... which probably makes it a feature that wouldn't see the light of day.

With regard to other crop modes besides 1.5x - yes, 1.2x, 1.3x, 2x, 5:4, 3:2 would all be welcome as long as the VF overlay wasn't expensive or caused other VF problems.

.
02-22-2015, 04:53 PM   #51
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QuoteOriginally posted by jonby Quote
I'm suggesting that it would be useful to go a little further than the 1.2x and 5:4 crops implemented on the D800 series and include something in between the 1.2 & 1.5x crops, plus other aspect ratios such as square, 16:9 and maybe more.
QuoteOriginally posted by jsherman999 Quote
1.2x, 1.3x, 2x, 5:4, 3:2 would all be welcome as long as the VF overlay wasn't expensive or caused other VF problems.
Maybe I simply lack imagination, but I can't see many users benefiting from such a 'kitchen sink' array of cropping options for stills. Although square would be interesting for Instagrammers, I guess.

Video ratios like 16:9 make sense, but you wouldn't use them in the OVF since you'd be shooting via the rear LCD or an external monitor.
02-22-2015, 05:56 PM   #52
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QuoteOriginally posted by kenspo Quote
They promised me from the start, that a FF would come. It helped me to sign the contract and leave Nikon.
You are under contract with Ricoh/Pentax?


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02-22-2015, 06:24 PM   #53
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QuoteOriginally posted by rawr Quote
Maybe I simply lack imagination, but I can't see many users benefiting from such a 'kitchen sink' array of cropping options for stills. Although square would be interesting for Instagrammers, I guess.

.
Every 'aps-c' lens vignettes a different amount and at different apertures, so a more granular cropping choice would allow you to fit it to the lens more.

I don't think it's any more questionable than a lot of other features cameras ship with I probably use maybe half the features my K20D or D800 have available. Interestingly enough I though 'crop mode' was a gimmick at first, but I use it more than I thought I would. Saves time in post, increases FPS, saves storage card space. Of course I have two aps-c lenses I shoot on my D800 still, if you're not doing that it's even less useful.

02-22-2015, 07:55 PM   #54
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QuoteOriginally posted by jsherman999 Quote
I think it would be a good feature if it could be fast enough.
Thanks for giving some consideration to these suggestions. Yes of course processing speed would be an important factor in its viability. I'm just trying to come up with ways of mitigating some of the negative aspects of having a 36mp+ sensor in the FF camera so that it can potentially meet the needs of a greater number of photographers/shooting situations. A number of contributors have expressed reservations about high res sensors due to the size and manageability of the files, so I think it's worth looking at providing better options for those photographers. An 18MP sub-sampled RAW option is a little too low for many, I suspect.

QuoteOriginally posted by jsherman999 Quote
Thing is it would basically be doing in-camera what you can easily do in something like Lightroom (which uses a 'smart' downsampling algorithm during export.)
I'm not sure that what I'm suggesting can be done in Lightroom actually, or any other program that I'm aware of (do correct me if I'm wrong though). As I understand it, when you downsample on export to DNG format from Lightroom (or DNG converter), you are forced to use lossy compression as well, no? What I am suggesting could be done in-camera is that image dimensions are reduced without using lossy compression, whilst also preserving bit depth, and output as DNG files. Personally I'd be much happier with a bit of downsampling than with anything resembling jpeg compression.

QuoteOriginally posted by jsherman999 Quote
With regard to other crop modes besides 1.5x - yes, 1.2x, 1.3x, 2x, 5:4, 3:2 would all be welcome as long as the VF overlay wasn't expensive or caused other VF problems.
Yes of course - nobody wants to compromise the viewfinder. Some other potential benefits of these crop modes (as seen on the D800 series) are faster burst rates and higher flash sync speeds - useful for some.

QuoteOriginally posted by jatrax Quote
I believe there was a Pentax patent for showing information in the OVF. Not sure what information but possibly the crops? They hinted that something different was going on in the big pentaprism housing.
Interesting - so maybe an alternative to the LCD overlay used by Canikon?
02-22-2015, 08:49 PM   #55
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QuoteOriginally posted by jonby Quote
I'm not sure that what I'm suggesting can be done in Lightroom actually, or any other program that I'm aware of (do correct me if I'm wrong though). As I understand it, when you downsample on export to DNG format from Lightroom (or DNG converter), you are forced to use lossy compression as well, no? What I am suggesting could be done in-camera is that image dimensions are reduced without using lossy compression, whilst also preserving bit depth, and output as DNG files. Personally I'd be much happier with a bit of downsampling than with anything resembling jpeg compression.
Well, Lightroom uses an adaptive Lanczos/bicubic resampling algorithm on export. It's not really 'compression', it's a resampling, with a smaller-dimension (or optionally larger) image as the result. I'm not sure how what you're proposing would be different/better, and you would have less CPU power in camera than in a typical Lightroom-hosting workstation anyway. Maybe I misunderstand what you're proposing, but I don't think anyone's going to beat LR/PS methods in-camera anytime soon... But if you're proposing something to match it in output quality - in camera - that might be nice.
02-23-2015, 01:38 AM   #56
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QuoteOriginally posted by stevebrot Quote
You are under contract with Ricoh/Pentax?


Steve
Yes Steve. Been for around a year now.
02-23-2015, 01:48 AM   #57
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If the k-5 has the best all-around sensor performance, then 36mp would be the magic number for full frame. That is, unless technology progresses.
02-23-2015, 05:14 AM - 1 Like   #58
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Re: Sensor resolution that makes sense on FF

QuoteOriginally posted by biz-engineer Quote
How many Mpixel does analog film has? Infinite?
This was discussed ad nauseum in the early digital photography days. Although I can't remember how the figure was determined, I recall that someone calculated that a high quality lens combined with a high quality 35mm film and scanned with a high quality scanner could deliver ~25Mpix of information.

I would be happy with a 36Mpix sensor; cropped to 2/3 gives me the same 24Mpix of the K-3 and ~7200 x ~4800 gets me 300dpi at my favorite print size. I do miss the low-light performance of the K-5IIs, so pushing pixel density even higher is not a plus in my book.
02-23-2015, 11:44 AM   #59
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QuoteOriginally posted by Buffy Quote
I recall that someone calculated that a high quality lens combined with a high quality 35mm film and scanned with a high quality scanner could deliver ~25Mpix of information.
That is the number of pixels for a 4000 dpi scan such as that delivered by my Nikon 5000ED. The actual resolution of the film itself is generally higher, but translation to Megapixels is problematic since a junk scan is a junk scan regardless of how many pixels are employed to record the junk. Film resolution is a better measure and can be used for direct comparison to theoretical sensor resolutions.

Resolutions for the better current B&W emulsions are respectably high. For example, T-MAX 100 has a MTF 50 of about 150 lp/mm. Specialty films such as Adox CMS II 20 and Rollei ATP claim much higher resolution (Adox claims 800 lp/mm...ha, ha, ha. Rollei claims 300 lp/mm). If one must talk megapixels, here is a link to a discussion on Flickr where the photographer claims 60 megapixel max for Adox CMS 20 with the Voigtlander Scopar 25/4 lens on 35mm film (note that is the previous generation Adox product):

https://www.flickr.com/groups/67377471@N00/discuss/72157638802164193/72157638806628644


Steve

(... It is probably best to not be attempting to compare apples and oranges based on the reflective index of their skins.)

Last edited by stevebrot; 02-23-2015 at 11:59 AM.
02-23-2015, 05:41 PM   #60
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QuoteOriginally posted by Buffy Quote
This was discussed ad nauseum in the early digital photography days. Although I can't remember how the figure was determined, I recall that someone calculated that a high quality lens combined with a high quality 35mm film and scanned with a high quality scanner could deliver ~25Mpix of information.
i think that about half of that film resolution might have been possible with an 8000dpi scanner and the very best film? the film guys just can't let go

here you can see where people who know about these things are arguing about 11mp. vs. mf film.

24mp or 36mp vs. film is not even comparable:

"Based on the equivalence of 10.2 micron pixels with film, I estimate that a full-frame sensor with 8.3 megapixels would have resolution equal to 35mm film. Slightly more pixels would be required for smaller sensors with lenses designed to cover full-frame 35mm. The simulated resolution of the Canon EOS 10D relative to 35mm film (82%) agrees well with my tests on the 10D. Likewise, the simulated resolution of the Nikon D100 agrees with Dennis Wilkins' tests.

The image on the right was cropped from a 3072x2048 pixel image taken with the EOS 10D. Details can be found on the EOS 10D page. It illustrates how digital cameras make highly efficient use of pixels; images tend to be sharper at the pixel level than 35mm scans. There are no MTF losses from film, film flatness error, development, or scanning (optical and mechanical). Sharpness is consistent and there is little noise/grain. That's why digital camera images achieve comparable perceived image quality with fewer pixels.

In interpreting these results, remember that resolution is not the only factor that influences image quality. Digital cameras with large pixels (over 5 µm) have far less noise (the equivalent of grain) than film, hence they will have better image quality with the same resolution. I find the image quality in my 6.3 megapixel Canon EOS 10D to be equal to 35mm film-- remarkable when you consider that 35mm film exposed and processed with excellent technique (fine lens around optimum aperture, perfect focus, sturdy tripod) can produce remarkably sharp 13x19 inch prints-- finer than most people realize. I haven't used much film (except for the Hasselblad XPan) since I got it.

Michael Reichmann's article, Ultimate Shoot-out, compares his 11 Megapixel EOS-1Ds to the medium format Pentax 67II. Although I agree with his conclusion that the EOS-1Ds has better overall image quality-- I'd buy one today if I could comfortably afford it-- I have to dispute one important detail: which camera has the higher resoluton. It's the Pentax. You can see it on the enlargements of the windows in the middle of the page, the second set of images under The Print Evaluation. A vertical line on the wall on the right is visible in the Pentax image but not in the EOS-1Ds image. Should this change Michael's essential conculsions? No. This thin line represents response at a very high spatial frequency that would have little effect on the appearance of a 13x19 inch image. It would be visible on a 24x30 inch image, but the 1Ds still has superior image quality due to the absence of grain-- see the discussion on Shannon channel capacity and image quality. Sharpness is only a part of the equation. Reichmann's earlier review of the D60, with side-by-side images from the D30, D60, 35mm and medium format cameras, is also worth reading.

The Foveon X3 sensor is an important step above the traditional Bayer mask sensor; images will look better at the same pixel count because of reduced artifacts (Moiré, etc.). But Foveon needs to increase the pixel count of its sensors to compete successfully."
Digital cameras vs. film, part 1
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