Thursday, July 28, 2016

Blown highlights and exposure Compensation

On a neighborhood walk, I photographed a white flower backlit by bright sunlight and against a dark background. As usual, I took a shot at 0 EV compensation and then with some negative EC. I decided to keep taking shots with increasing EC. Those shots were taken with center weighted metering. Then I switched to spot metering. All pictures were taken with a Panasonic FZ1000 bridge camera in P mode and Automatic white balance. I'm posting these OOC Jpeg images  as visual examples of how EC changes the final image.

EC values: 0, -0.33EV, - 1.00EV, -1.66 EV, - 2.33EV, - 3.00EV, -3.66EV.  The last image with spot metering has 0.0 EV with the cross hairs on the bright part of the flower.

As I added negative EC, I reduced the blown highlights.  However, I also reduced the sense of light on the flowers.  With too much negative EC, the image doesn't look like what I saw through the viewfinder.

Changing to spot metering takes a bit more time (and I have to remember to switch back to center weighted meting) but for a difficult subject like this one, it is often the most reliable method of dealing with blown highlights.

Friday, April 15, 2016

I read a post about the joys of "vinyl" and its superiority over digital music formats on a mostly photography blog site and felt the need to express a different opinion.

After decades of experience with LPs, turntables, phono stages, tapes and tape drives (starting in the mid-60s, I had vivid memories of the practical problems with tape and LPs. I was happy enough to see a new medium with far fewer problems and much better real world sound.

Tape noise, LP surface noise, warps, wow and flutter, hum picked up by the turntable to phono stage cable, scratches and defective pressings are still vivid memories. I have no need to experience them again.

All my music collection has been on a computer hard drive (with backups) for about 10 years, indexed so that I can find and play what I like without effort. As always, sound quality is a question of the care with which the recording and the subsequent steps were made and the skills of the people involved.

Most of the recordings that I own has never been available on vinyl. I buy used Cds on Amazon and have few problems getting perfect transfers. I buy Flac downloads and find that ever easier. I listen on YouTube to music that is not available via commercial recordings. I can download concert recordings from that last few decades.

I miss nothing about LPs and the associated gear. This talk about how wonderful "vinyl" sounds like old guys talking about how wonderful film and darkrooms were.

Monday, March 23, 2015

See those wildflowers now, they will be gone soon

Whenever we visit wildflower areas in California, we are conscious that the flowers will wither and fade as the plants cycle progresses. When we visited Antelope Valley and the Carrizo Plain area this year, we saw that solar energy installations had replaced some fields of flowers. We had a sense that we we return in coming years, there will be fewer fields of flowers and more development.

Wildflower field in the Carrizo Plain area

The Carrizo Plain National Monument itself is not threatened but the private land north of the monument is being converted into large scale solar energy farms. The installation of dense rows of solar panels disturbs the soil and the panels shade out vegetation beneath the panels. As more of these developments fill the north end of the plain, the National Monument will be cut off from the land farther north. The Carrizo Plain has been part of a band of undeveloped land that stretched for about 150 miles from the south end of the monument to the edge of the city of Hollister. The value of the monument as part of a larger natural environment is being diminished.

Solar energy farms are replacing fields of flowers in the Antelope Valley as well. We saw new solar installations along Highway 138 and the side roads where we had seen flowers in the past. The Antelope Valley California Poppy Reserve is not threatened but many of the best flower areas are outside the reserve. Development for homes and businesses as Lancaster and Palmdale expand westward also threaten to replace fields of flowers. Antelope Valley's flowers can be enjoyed on an easy day outing by the large urban populations of Southern California. If we expect urban Califorians to value California's natural environment, we need to preserve places like the flower fields of Antelope Valley so that people can see experience the beauty of nature for themselves.

For several years, the development of solar energy has had a gold rush character fueled by government land give-aways, massive subsidies and short-circuited review processes. The result has been to site installations without adequate consideration for the effect on the natural environment. It will take much more public awareness and concern to replace the gold rush by a process that doesn't permanently damage the natural environment in California.

Sunday, March 22, 2015

Taking pictures in the last hour of daylight

Several times in a recent 9 day wildflower trip as the light level got low, we saw new and interesting flowers that we wanted to photograph. We got some good pictures but we missed others. Some of our pictures were usable but not as sharp as we normally get.

The low light level resulted in slow shutter speeds and made it harder to see the subject well enough for focusing. There was often a breeze blowing which moved the subject around. Lesley uses a monopod and I use a tripod; that helps keep the camera steady but it doesn't help with a moving subject. When you are down to a 1/8 second shutter speed, a gentle breeze is enough to produce a blurry image. An example:

This one is almost sharp.

This one is less sharp.

A breeze made this image completely blurry.

The experience made me think about ways to improve results.

- Increase the sensor sensitivity (ISO value). We normally use ISO 400 and change to 800 as light levels fall. However, if we are losing shots, why not try 1600 or 3200? Each doubling of the ISO setting doubles the shutter speed.

- Upgrade to the latest and greatest camera model. That might allow us to use 3200 or even 6400 with the same results as 1600 or 3200 with our current Panasonic G6 cameras. This is an easy, obvious improvement but it costs real money.

We usually use aperture values of f7.1 or f8 to get enough depth of field to get all of the subject in sharp focus. However, we could use f3.6 or f4 to get a doubling of shutter speed. At our usual working distances (12-14 inches from sensor to subject), depth of field would be reduced. Backing away to 19 inches would give our desired depth of field at the cost of a small subject on the image.

Carry a small “tent” to shield the subject from wind. We often work close to our car on these trips so carrying a “tent” made of plastic sheeting with short rods to hold the plastic in place may be feasible.

Use flash to get more light and to freeze the subject. The built-in flash isn't great but I could try it. An accessory flash unit would be much better but they cost real money.

Monday, September 22, 2014

Macro photography should not be just a club for technique jocks

Defining macro photography as requiring 1:1 and greater magnification is rather absurd. Few currently macro lenses go above 1:1 and many older lenses only go to 1:2. Do we exclude older lenses and only allow current macro lenses when they are used at their minimum focus distance? Do we require that additional equipment such as extension tubes, bellows, additional lenses be used with a regular macro lens to make it legitimately macro photography?

It seems more reasonable to define macro photography as taking pictures of small objects close up to reveal detail that can't be seen with the naked eye.

I believe there are two quite different kinds of macro photography:

- Still life style pictures of plants and dead or immobilized insects in a controlled environment . (and stamps and coins.) The subject will stay put as long as the photographer needs to get the exact picture that he wants. The environment allows him to use all the equipment for lighting the subject and holding it is place. Getting greater than 1:1 magnification is feasible but it requires skill and good gear. This sort of photography attracts people who want to demonstrate their skill in mastering difficulties. Their discussions focus of technique with harsh criticism of those who post less than perfect images. Arguments about the only correct way to do macro photography break out easily and quickly descend into name calling.

- Nature photography of living plants and insects in uncontrolled outdoor environments. At any moment, a breeze may move a flower out of focus or even out of the frame. An insect may light on a flower, be there for a few seconds and the leave. The emphasis is on getting a photo of the subject while the opportunity exists. Setup for a photo has to be minimal. Carrying extra gear for lighting or holding the subject in place may be impractical. Magnification greater than 1:1 is often infeasible. The emphasis is on capturing a record of what the photographer encounters for the love of the subject matter. The joy is in capturing interesting subjects rather than in a demonstration of skill. Discussions among such photographers focus on the subject matter rather than on critiques of technique.

Technique jocks who practice the Still life sort of macro photography seem unwilling to accept the other kind of photography. On some photography forums, they drive off anyone who posts photos that don't fit the greater than 1:1 criteria. The result is that nature photographers have no place to discuss their concerns and their photos on many photography forums.

Sunday, September 21, 2014

Old guy interests

I'm a bit sad that several of my interests (audio gear, camera gear and sports cars) acquired a long time ago increasingly look like old guy interests. And I'm disgusted by the rich guy/conspicuous consumption aspect to those interests.

Gear head hobbies now seem sterile to me and gearhead forums seem populated by people I'd rather not know. However, listening to good music, looking at pictures of subjects I value and driving on winding, country roads are still rewarding activities for me. Those interests attract positive, interesting people.

Tuesday, April 1, 2014

Collecting recordings of classical music

Someone asked these questions on the forum

Do you settle on one that you listen to? When you buy multiple versions of, say, Mozart's Requiem, are you looking for the one you consider to be the best or do you want different listening options? Or are there times you want to listen to X's version of Mozart's Requiem, and other times you want to listen to Y's version?

In the beginning, I wanted to get a copy of all the classical music that I knew I liked really well. Then I wanted to explore other things by the same composer or similar composers. Decades ago, buying recordings was the only way that I could hear things that were not on the beaten path (radio and cvoncerts.) So I purchased recordings of lots of Mozart and Beethoven and so on. Then I wanted to explore more recordings of favorite works in search of the "perfect" performance. Then I wanted to explore more performances to hear different interpretations.

Initially, I concentrated on orchestral, concerto and piano music. Then I began to explore more chamber music. Piano trios, quartets and quintets wwere easy to love. String quartets required more time and effort from me.

When I found exceptional performances, I wanted to recordings of other works by the soloists, conductors and ensembles that had impressed me in one recording. I'm still filling out the gaps so that I can listen to any classical music that I want to try. I'm still filling out my collection of the relevant recordings by the performers I really like.

All my collection is on a computer hard drive managed by the excellent JRiver Media Center software. When I browse my collection, it is often a voyage of discovery. A composer, a work name or a performer name catches my eye and sends my browsing in an unexpected direction. The particular performance of a work that I choose to mplay may be determined at the last moment.

Friday, October 12, 2012

A new MusicPC

A few weeks ago, I made some changes to my dedicated MusicPC.  Here are the changes and the things not changed:

old  ==> new configuration

Intel G6300 Core 2 Duo CPU (1.8 GHz)  ==> Intel G530 Sandy Bridge CPU (2.4 GHz)
2 GB RAM  ==> 8 GB RAM
Intel G945 based micro-ATX motherboard         ==> Intel H67 based micro-ATX motherboard
(2 PCI slots)                                                          (1 PCI slot)

Windows XP Professional                         ==> Windows 7 Home Professional
JRiver Media Center 16  ==> MC 17
UltraVNC remote control s/w                    ==> not installed yet

(no KVM switch)                                     ==> KVM switch (USB keyboard and mouse)

Antec Solo case                                       ==> no change
Seasonic SII 380W power supply            ==> no change

Seagate 500 GB 7200 RPM hard drive   ==> 128 GB Crucial m4 SSD (OS boot drive)
Western Digital 2 TB 5400 RPM 3.5" hard drive ==> no change (music storage)

Some notes:

1. I was feeling cheap.  I kept parts that still worked well and chose new parts that were adequately fast and not expensive.  The changes cost about $ 400.  The process took time of building the new system took time and was not fun but it was very routine.

2. The G945 motherboard had been a trouble free sweatheart for over 5 years but a couple of USB ports had failed.  I wanted to switch to a new system before a wider failure occurred.  Windows XP had been fine but I wanted  to have support for > 2 TB hard drives (for backup) on the MusicPC.

2. IvyBridge components were available but I chose a Sandy Bridge CPU and motherboard.  The G530 CPU chip was fast enough and cheap.  The Intel H67 based uATX motherboard was cheap and had a PCI slot that allowed me to continue to use my ESI Juli@ soundcard.  The H77 based equivalent motherboard was significantly more expensive and did not have a PCI slot.

3. I had been operating the MusicPC using UltraVNC software for remote control from other PCs (my PC, my spouse's PC and a laptop.)  Now I'm using a KVM switch to control the MusicPC from my personal PC and JRiver's TRemote functionality to control JRiver MC from other PCs.

4. I did only minimal tuning on the new configuration.  I turned off Windows update, hard drive indexing, no anti-virus and no system restore checkpointing.  I wanted to preserve network functionality and normal support for Windows applications.  I monitored activity using various system tool including the DPC latency checker, Task Manager and Process Explorer.  When I'm playing music with MC, there isn't much else going on.  I am not conscious of a change in sound quality between the old system and the new one.

5. The MusicPC boots and start MC in a bit under 30 seconds.  That's about the same as for the previous more optimized Win XP based system.  Power use is down from 75-80 watts to 35-40 watts.  I think a modern Seasonic G350 power supply would make a difference of close to 10 watts.

I expect this MusicPC system to remain in use for at least 5 years.  When it needs to be replaced, a compact form factor PC like a Mac Mini will be a likely choice.  Either a 2TB 2.5" drive or 1 or 2 SSDs storing 2 TB will be sufficiently cheap.  I'll move to completely USB based audio output on the MusicPC by then.

I've felt for some time that computer based music playback was becoming mature.  Building a new generation MusicPC felt like a concrete step toward that maturity.  The old system worked just fine and the new system works equally well.