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Dealing with large digital files for events and other applications where large file size is not necessary.

Dealing with large digital files for events and other applications where large file size is not necessary. Ok, admit it. It’s a first world problem. Your yacht, house, digital file is too big. But if you are photographing events with say, a Sony A7rII, this really is an issue. You reasonably won’t want to shoot JPGs, which can be dumbed down in camera settings. But you should shoot raw files that can’t be reduced in camera to a reasonable pixel count, they’re always 42mp on this camera.  So here’s a strategy to consider. Use the Adobe DNG Converter app to both compress (or further compress) and at the same time reduce the pixel dimensions of your raw files.  Give this a try (see screen shots): Download Adobe DNG Converter (free) Select folder for files to convert, and destination (maybe try testing this on your memory card with your latest images first) Rename if you like In the bottom dialog box change preferences to the most recent compatibility, jpg preview to full size (speeds ed
Recent posts

Should I ditch my Sony a6500 for a A7r IV?

Recently, I bought a Sony a7r IV. The main reason was for stock photography. The high resolution along with improved focusing and biggish buffer would allow me to make better people (and other) stock photos for my various stock endeavors.  The Sony system has treated me well. I own two A7r II's for stock and other work, and two a6500's for event photography. The A7r II's aren't ideal for events for a couple reasons. The focus tracking is pretty good, but maybe not enough for fast paced people on stage. Another reason is that silent shooting is only available on single shot mode. And (admittedly a first world problem,) the files are much bigger than needed. Well, the last problem, too big files isn't an issue with the A7rIV if you use it in APS-c mode. The files are effectively the same size as the a6500: 24 mp. Focus with the IV is even faster and more effective than the very capable a6500. And with those smaller files, the IV has no problem with buffer overflow. So

Lossy DNG File Sizes by ISO.

Fairly recently I discovered the magic of lossy DNG's. My stock photo library is ever growing. Though JPG's might really be enough for my archive, I've been keeping my raw files. RAW files take up lots of space. And RAW files can't typically keep user generated EXIF data in the file. RAW files keep their keywords and other metadata in a sidecar, that is if you regularly save the EXIF data to file. So recently I've been converting all my RAW files to lossy DNG's. After testing the highest ISO setting on the new-to-me A7R IV, I converted the files to lossy DNG's only to find a surprise. The very high ISO lossy DNG's were much larger than the original Sony RAW files! Lossy ARW vs Lossy DNG full image sample So I thought it would be a good test to shoot from the lowest to highest ISO, convert to lossy DNG and see where the file size savings invert. Here's the data as seen in the above screen shot: ISO Lossy Sony ARW Raw file size (MB) Lossy DNG file siz

Negative scans with a new method

  For years I used a Nikon Coolscan to scan my slides and negs. Those scanners use a less-common Firewire connection (Apple sucks!) Now at the school lab I run, we use Epson V700 scanners. The quality of scans for 35mm especially leaves a lot to be desired!  Here's what I did...... Put my Sony A7rII with a macro (a real macro that can do 1:1) on a copystand Put a flat panel LED light box on the stand Put my negative in a negative carrier (I tried a few carriers, in this case the neg carrier is for a Besler 45) Put a couple of boxes (in this case 100' rolls of Kodak Plus X from the 1980's) to space out above the light box (prevents dust showing from on the lightbox) For comparison, I also scanned a set of negatives on the Epson V700. The results showed me that I shouldn't be scanning 35's on the Epson! Epson vs Camera Scan, overview Right off the bat, some of the exposures from the Epson in default mode looked pretty crappy. But I chose this Epson scan (on the left)

The Making of a 1.7 Gigapixel Infrared Stitched Photo

  Here's an example of 45 20megapixel photos stitched together. ca: 88x40in @ 300ppi ca: 132x60 @ 200ppi ca: 260x120 @ 100ppi (~21x10 feet!) It's possible to stitch without distortion like that shown in my example. Also, FYI the camera is a tiny mirrorless camera (sony a5100) that was modified by removing the infra-red filter that covers the sensor.  It's hard to wrap your head around the process. Typically, you will be using a moderate telephoto lens for the process and can make a super-wide angle final pano. In this case, the lens was a 50mm on APS-c (75mm equivalent).

Vintage Minolta AF vs Less Vintage Canon Macro Lens

 Surprise!  Wide open the much less expensive old Minolta 50mm Macro outperforms Canon's 50mm f2.5 stopped down to f2.8  But wait, there's another twist....look at the out of focus areas in front of the focused areas. Though the Minolta was visibly much better wide open, it has some ugly rendering in this area. Stopped down there's little difference in the sharpness of both lenses. But the weird rendering of the Minolta was something of a disappointment. Though honestly if I wasn't looking at results side-by-side I don't know if I'd care.

Voigtländer Color-Skopar 28mm f3,5 on Sony Full Frame Mirrorless

 If you want the TL:DR version of this, the Voigtländer Color-Skopar 28mm lens is absolute crap on my Sony A7RII. Check out the samples. So I work at Mills College in Oakland California. We got an amazing donation - well actually several separate donations from someone who's mom graduated in 1939. There was a Leica M3 and a number of lenses for said Leica in the donation. The school doesn't have any mirrrorless cameras, but I do and wanted to test out some of these classic legends to see how they fair against modern lenses.  There were a few reviews online like this one I found that talked positively of this lens. Can't say I agree. I bought a Fotodiox (or as my friend refers to this company "Foto Detox") Leica M- to Sony FE adapter . It was $20 and is a simple adapter that all it does is hold the lens in place on the body. I believe they also make an adapter that will autofocus which blows my mind.  In any case, I put this lens on and walked around campus to do a