Wednesday, September 23, 2015

Why has Sony been using lossy compression in their raw files for the A7 and others?

As a software developer, the loss of data has always been inexcusable to me.

I don't understand who would make a decision to use lossy compression for files that encompass all information about a photo, as others have used lossless compression.  Yes, I understand that the file sizes would be huge because of the amount of information, due to the number of pixels the image sensor contains.

Surely, a person buying a camera with a sensor having more than 24 megapixels would understand what a huge problem it is to store and process the files.  Even the JPEG files would be huge, and they use lossy compression.  (Always keep your original JPEG file from the camera and work from it.)  This last bit is unfortunately impossible with the lossy raw file.  You're not getting all the data from the start.  Sad, that.

Friday, September 11, 2015

Not convinced about the Panasonic GX8 Dual Image Stabilization

I bought the Panasonic GX8 a few days ago, along with the 12-35mm f/2.8 lens.  After the GH3, Olympus E-M1, and GH4, it seems that the GX8 has a couple of interesting features, including the tilting EVF and the Dual I.S.

Previously, the 35-100mm f/2.8 I dislike so much was the only lens I had with Optical Image Stabilization (OIS), but I changed that with my purchase of the 12-35mm f/2.8 lens.  With an extra US$200 off, it seemed a useful purchase, rather than buying another Olympus 12-40mm f/2.8 lens.

When viewing video I've taken with the 35-100mm lens, I'm often reaching for dramamine because the OIS doesn't seem to work well, especially compared to lenses that don't have OIS.  It is a compromised design that probably should have been much, much bigger.  Instead of the 58mm filter size, it would probably been sensible to make the lens big enough for a 67mm filter size.  The 12-35mm lens is equally small but feels a better build.

Around 8:30 p.m., earlier than the usual 10 or 11 p.m., I took the GX8 out with the 12-35mm lens mounted.  I wanted to see how the Dual I.S. would work.

I would say that I'm not terrifically satisfied.  Hopefully, firmware will improve the functionality.  At this point, I switched to the Panasonic/Leica 15mm f/1.7 lens.

Hopefully, the in-body Image Stabilization is working well.  I'm not entirely convinced but it probably works as well as that of my Olympus E-5 from 2010.

Update 2016.11.13: As I've seen with the newer Panasonic bodies, the IBIS from the smaller GX85/80/GX7 Mk II and G85/80 is much better, plus they've implemented an electromagnetic-driven shutter mechanism to correct for shutter shock or whatever the term is.

Out of all the comments I've seen, only one person has said that he gets some value from the GX8's IBIS and he said that he got better shots than with the GH4.  That is not my experience, unfortunately, nor does it seem to be the experience of the majority of commenters.  I have better shots with the GH4, and certainly with the Olympus E-M1.

If it works, I can't tell any difference.

Wednesday, September 9, 2015

Panasonic GX8: great second body to GH4, alternative to Olympus E-M1

I'm a long time Olympus user, having used the OM-1N, IS-20DLX, D-300L, C-2500L, E-1, E-5, and E-M1.  My first micro Four-Thirds camera body was the Panasonic GH3.  I traded this for the E-M1 before the trade-in value might have fallen.  About nine months ago, I got the Panasonic GH4.

Today, I bought the Panasonic GX8.  It is quite a bit of money, but it's also a bargain compared to the GH4, giving you a lot of the functionality, plus having a couple of unique items.  I happened to get it with the 12-35mm f/2.8 lens, when there was a US$100 instant rebate on the lens, and an additional US$200 instant rebate on the bundle.  This made the combination about US$1900.00.

For me, the GX8 fills a gap while my Olympus E-M1 is out for repair.  Someone damaged the eye cup mount with a BMX bike, and I apparently passed the 150,000 shutter actuations for which the shutter mechanism is rated.

The GX8 also helps as a secondary 1080p video camera.  There are times when I could put one of the camera bodies on a tripod and let it record separately, while I work the other by hand.  The E-M1 is sufficient for video, but it's hardly great.

Why I like the GX8:

The mode dial is right above the exposure compensation dial.  The mode dial includes 3 custom settings, although the C3 position holds 3 separate sets, just as the GH4 does.

The other dials are similar to any other Rangefinder-like mirror-less body.  There are a number of function buttons, labeled and unlabeled, but the Fn buttons have no numbers.

The fully-articulated rear display is extremely useful, as it is on the GH4.  However, it's the tilting EVF that is so amazing.  The display used seems to be the same one that the GH4 has.  The display is extremely clear, and so is the rear display.  Oh, and the rear display can be turned inward, to save on battery life, and to protect it.

The grip is substantial.  I wish that the battery was substantial but it isn't.  I'm still trying to determine if it's the same battery from the GX7.  (It's supposedly the battery used in the GH2.)  However, the grip feels amazing without being huge.  I have complained about the Olympus E-M1 grip and the tiny battery.  This is what they could have done with the grip.

I'm sure plenty of people will complain about the overall size.  The size is a benefit for me, and I have no pre-determined size limit for micro Four-Thirds, especially coming from Four-Thirds.  The E-M5 is uncomfortably small, and the E-M1 is uncomfortable because of the angular grip.  I never have held the GX7 but I would expect that it is too small for my comfort.  My hands and my use don't represent anyone else: Your mileage may vary.

I took a few shots before the battery died.  (Since it had been out for a few days on the shelf, the battery had been depleted.)

Moon cakes through the window

Update 2015.09.12: Battery life is extremely bad for me so far.  I thought that having the rear display closed would help.  I'm really not sure, but something seems terribly wrong.  I had taken some photos the morning on September 11th, from/to the post office.  I didn't touch the camera until Saturday the 12th.  I took a few photos while walking to a skate park.  Got a few photos there and it complained about the battery.  I didn't have the extra, third party battery, so I turned it off and walked back to the car without taking any video.

On the up side, people may find the shutter sound to be endearing--it's like a leaf shutter's sound.  Hopefully, that doesn't mean that it isn't durable.

Maybe, I've missed some settings.  I found that I had not saved to a custom set after switching to raw files, and I got JPEG files at the skate park today.

As you may have already seen in another blog entry, I'm not sure if the Dual I.S. is working properly.  I expected more from the GX8 + 12-35mm f/2.8.

Update 2015.09.14: Yesterday, I shot at a familiar skate park only with the GX8.  Now that the custom set has been saved, the camera is more likely to do what I want.  As a stills camera, it is quite useful.  However, since December I've been doing video, mostly with the GH4.  It's a tough act to follow.

The GH4 has a good set of physical controls and a great grip holding a great battery.  I can go through three E-M1 batteries and still have a charge left on my second GH4 battery.  The GX8 battery is 1220 mAh, just like the E-M1 battery.  With the GX8's display facing inward, it might not use as much energy, plus you can't easily change the focus point, as you can on the E-M1.

The GX8 defaulted to the same 1080p video parameters that I use on the GH4.  I could go for higher quality but I'm not making films.  I'm making skate park videos.  It has to be fairly steady and you need to be able to keep up with the action.  Naturally, you can do 4K, but I've had around nine months to do that and I've found very little use for it so far.

The real disadvantage of the GX8 is the placement of the video enable/disable button, which is on the top plate.  Yes, I should have a finger up there already, and I do--for the shutter release.  The placement of the video button is inconvenient, but as anyone can adapt, it isn't a serious problem.  It does take a certain acclimation to get it to work reliably, but it's not as bad as my trouble with the GH4's button where I have to almost stab it sometimes to get it to start/stop.

Processing the video files was exactly the same as with the GH4, and it should be easy to mix files from the two.

I also tried the Face Detection and while it works in the strictest sense, it's not very reliable.  It works, but there is a delay, whereas the Olympus E-M1 finds faces almost immediately, and rarely has a false positive.  Considering how poorly the E-M1 does video, the balance is just fine.  Why else would I have Olympus and Panasonic equipment?

Update 2015.09.15: The GX8 works quite well in stills shooting situations, better than I expected.  I stopped quickly last night to get photos of a double rainbow and it didn't take as long (as the GH4) as expected to wake from sleep.

Update 2015.09.30: An ugly EVF problem has returned to me with the GX8.  Using the EVF with sunglasses can often end up with a blackout.  The GH3 was bad and I learned to adapt to the E-M1 and GH4.  Immediately using the GX8 without the sunglasses, it was fine.  The EVF's vertical angle doesn't matter.  It's the angle of the sunglasses to the EVF that causes the problem.  I hope that I can adapt, and the problem lessens.  There is another eye cup available but it's barely available.

The lower frame rate of burst mode can be a problem for skate park photography, but shouldn't be a problem for any other application.  Between the E-M1 (10 fps) and the GH4 (12 fps), I can overdo it, but with the correct timing, I can get almost any shot.  The Nikon D7200 is supposedly a good sports body and at 6 fps, it's a bit slower.  It works well enough, except in lower light, where the D7200 won't allow me to take a photo, except in the extreme ISO Black and White modes.

Update 2015.10.18: DxO Optics have been testing the GX8.  As they're assessing each camera body for their software configurations, the measurements should be accurate but how much it really means, I'm not sure.  Looking at many of their results, I would think a lot of camera bodies are unusable.

GX8 has the best score, but not the Sports ISO figure.  However, I have the GX8, GH4, and E-M1, plus the Nikon D7200.  The D7200 is rated much higher at 1333 and I'm not really seeing the improvement.  It could be the same way I used to look at Olympus E-5 and Nikon D300 photos.  The E-5 photos looked about the same at ISO 1600 as the D300 looked at ISO 2500, better but not incredibly impressive.

There is a bigger difference between the scores than I've seen in real world experiences.

Batteries: D7200, E-M1, GX8, GH4, E-5

Update 2015.10.19: Took a quick photo of the batteries, where the  GX8 and E-M1 batteries are far too small at 1220 mAh, especially since the GX8 has a good-sized grip.  The battery for the Olympus E-5 has 1620 mAh capacity.  The Panasonic GH4 has 1860 mAh and the Nikon D7200 battery has 1900 mAh.  The dSLRs can last a great deal of time on the battery, and so can the GH4, even though it has an electronic viewfinder.  Sadly, the GX8 and E-M1 don't have enough capacity.

Update 2015.11.19: The GX8's 1080p video capabilities are good, and it's a responsive body.  Using video from it and the GH4 is easy and any visual differences, not due to the lenses, seem absent.  I'm ordering a third battery, just in case.

Since the E-M1 is back from repair, it's interesting to have a couple of compatible bodies from different companies.  It's much easier to get the E-M1 to do face detection, so people photography is better with Olympus.  Of course, video is better with Panasonic.  Having smaller cameras is quite good, except for the small batteries, though the GH4 almost always feels like an extension of my hand.

The tilting EVF has been of occasional use, but I wasn't sure it would be an asset or not.  During extremely sunny days, it can eliminate problems at certain angles where I would have to use the rear display but the articulated display is more functional for architectural shots.

Update 2015.11.25: Post focus is included in firmware version 2.0 and it's fun to try.

I'd never tried 4K Photo mode previously, but I held the shutter release and let it do its thing and then, let go.  Since it uses video mode, the electronic shutter is employed and there is no shutter noise.

You then tap the rear display in the upper left hand corner where the icon seems to show multiple layers.  Once in that mode, I selected a point on the display, and it asked if I wanted to save to a photo.  When I confirmed that I did, it saved a file that seemed to be focused where I wanted.

I'm not sure if there is anything more to it.  That seemed so easy to do without instructions.

Update 2015.12.26: Someone told me that the E-M1 and the GX8 were completely different kinds of cameras.  I couldn't understand how the placement of the EVF from corner to center changed the way that the body worked.  I use the two almost interchangeably.  To me,  every camera body (not of the same model) will be a bit different.  We adjust, do we not?

As it has become colder, it's more difficult to do video, since I'm often wearing gloves.  The recording button on the GX8 is particularly small but even the button on the GH4 is difficult to activate without gloves.

Update 2016.01.01: Went to San Francisco and took a few photos as a tourist with the Panasonic 25mm f/1.7 and a wide angle/macro converter, as an experiment.

Panorama with 25mm f1/.7, wide converter

A buddy used the panoramic mode and it worked well enough.  Conditions were not exactly favorable, as it was nearing sunset and the wide angle/macro converter adds optical problems to a lens that isn't amazing.  I probably should have tried the iPhone to take another panorama, but I'd run out of power.

Update 2016.02.22: The GX8 continues to impress with both stills and video.  Equally, it has some of the same occasional difficulty with AF that the GH4 has.   The interaction between the 25mm f/1.7 and the GX8 at a skate park left me wondering if they're both in need of firmware updates.

I was surprised to find that the firmware has a number of languages available, unlike the GH4 with only English and Spanish.  I wonder why French wasn't included on the GH4, given that Canada and the U.S.A. are so close.  Coming from Olympus, Japanese is always available and the GH4 really messed with me, so it's good to have Japanese available on the GX8.

Update 2016.09.27: For a while now, I've seen user experiences and reviews on the GX80/GX85/GX7 Mk II that suggest that it surpasses the GX8.  I'm not sure.  The sad thing is that the G8/G80/G85 is now available and seems to be everything that the G80 is, but with a weather-sealed dSLR-style body.  Except for the Panasonic 25mm f/1.7, I've had a very good experience using the GX8.

If there is one flaw, it's the same one as the GH4 has--the CPU is underpowered.  However, it loses focus less than the GH4.  Using Face Detection is an unfortunate mess, unless I have loads of time to wait.  Otherwise, it defaults to the 49 area scatter pattern, which is less than helpful, unless I truly want to focus on the fence or wall behind the person.  Olympus is far ahead in adding Face Detection to any AF mode.

Firmware updates haven't helped much.  They've added functionality, such as Post Focus.  Post Focus is a simple process to emulate what the Lytro brand cameras do.  You take a number of photos at different focus points automatically and choose the one you want to keep.

Update 2016.11.13: As I've seen with the newer Panasonic bodies, the IBIS from the smaller GX85/80/GX7 Mk II and G85/80 is much better, plus they've implemented an electromagnetic-driven shutter mechanism to correct for shutter shock or whatever the term is.

Out of all the comments I've seen, only one person has said that he gets some value from the GX8's IBIS and he said that he got better shots than with the GH4.  That is not my experience, unfortunately, nor does it seem to be the experience of the majority of commenters.  I have better shots with the GH4, and certainly with the Olympus E-M1.

If it works, I can't tell any difference.