Wednesday, May 31, 2017

Photographing night skies with medium format

Phase One XF, IQ1-100 Schneider LS45mm
f/2.8 10-seconds ISO 3200 10:24pm

This this not meant to be a discussion on which is better, Phase One or Fujifilm 50s.  What I hope to accomplish is showing just how well either system is in capturing nightscape photography using high ISO and long shutter speeds.  If you think you’re about to read how I favor one over the other then give it up and stop reading.
Let's begin our discussion with the following observations.  Up until a very short while ago you couldn’t think of capturing the Milky Way or any nightscape images using digital medium format.  That is unless you had a Phase One P45+ which is capable of 60-minute exposures.  I’ll only address Phase One and the new Fujifilm 50s as those are the two systems I’m familiar with so if I miss a product from Leica or Hasselblad please forgive me.
2-shot panorama
Fuji GFX 50s GF63mm
f/2.8 5-seconds ISO 800 2:34am
Phase One introduced their first CMOS sensor with the 50 megapixel IQ150 crop sensor offering ISO range between 100-6400 and a 60-minute exposure.  Phase One now offers a 100-megapixel IQ1 and IQ3-100 full frame sensor with an ISO range of 50-12,800 and a 60-minute exposure.  The Fujifilm GFX 50s is a crop 51.4 megapixels sensor offering ISO range of 100-12,800 (extended range of 50-102,400) and a 60-minute exposure.
When you research night photography all the information is centered on using a 35mm system which makes sense when you think about it.  The sensor used in 35mm is a CMOS while the typical medium format is CCD. (CMOS is complementary metal oxide semiconductor and CCD is charged couple device). CMOS sensors will typically offer a better battery life as well as higher ISO. The other difference is a slightly different color and dynamic range offered between the two-sensors.

Phase One XF, IQ1-100 Schneider LS 35mm
f/3.5 5-seconds ISO 800 11:42pm
Since 35mm has been the king of the hill the vast majority of images produced are from them as well as historic testing.  What I’ve been doing is reading the 35mm testing and attempting to use it in using medium format.
The 500 Rule.  This rule is simple on the surface; divide 500 by the lenses being used. If you’re using a 21mm lens, 500 divided by 21 equals 23.80 (rounding down to 23).  23 becomes the longest shutter speed I’d use using this lens before introducing star smear.  This is fine if I’m using a standard full frame 35mm camera such as a Sony A7rII.  What about medium format…
Fujifilm GFX 50s GF32-64 at 32mm
f/4 8 seconds ISO 3200 2:44am

Take a look at any medium format lens and it will offer the equivalent range in conventional 35mm terms thus the Phase One 45mm f/2.8 when used on my IQ1-100 is 28mm and my Schneider LS 35mm is equivalent to 22mm.  Take a look here on Capture Integration's web store for information on the Schneider 35mm.  Keeping these equations in mind, when using my Phase One XF, IQ1-100 I factor in the 35mm equivalency dividing 500 by 28 for the 45mm (17-seconds) and 500 by 22 (22-seconds) the 35mm.  I also err on the safe side by rounding downwards for the maximum shutter speed.  This works since I’m using a full frame digital medium format sensor with the 100-megapixel IQ1-100.  What about crop sensors..
Fujifilm GFX 50s GF63
f/2.8 5 seconds ISO 1000 2:54am
The Fujifilm 50s medium format camera uses a crop sensor of approximately 0.79 rounding up to .80 for ease.  I currently have 3-lenses with a 4th-on order.  The crop factors of the current lenses are as follows.

GF 32-64mm f/4 is equivalent to 25-51mm in 35mm and has an equivalent 35mm f/stop of f/3.2
GF 63mm f/2.8 is equivalent to 50 in 35mm and has an equivalent 35mm f/stop of f/2.2
GF 120mm f/4  is equivalent to 95 in 35mm and has an equivalent 35mm f/stop of f/3.2
GF 23mm f/4 is equivalent to 18mm in 35mm and has an equivalent 35mm f/stop of f/3.2
Based on the above information I divide 500 by 25 (20) for the 32-64 if shooting at 32, 500 by 50 (10) for the 63mm and 500 by 18 (27) for the new 63mm.
All research so far show the wider the lens the better it is for nightscape and Milky Way images since the wider the lens the longer the shutter can be opened before star smear.
Fujifilm GFX 50s GF63
f/2.8 10 seconds ISO 3200 11:50pm
I’ve covered shutter speeds and will address ISO next.  Your ISO setting will depend on the environment you are shooting in as well as how fast your lens is.  A lens at f/2.8 can capture at a lower ISO than one which is f/4.  You’ll also need to experiment as you shoot.  I normally will begin at ISO 1600 and go to 3200 if needed or lower to 1000 or 800.  The final figure depends on what I see on the histogram.
Another factor is noise.  The higher the ISO the more noise you’ll introduce thus the need for “dark frames”.  The easiest way to describe this is that when using a dark frame the amount of time you shoot a single capture is double; a 20-second exposure takes 40-seconds.  Phase One does this automatically while Fujifilm GFX 50s must be set up.
Phase One XF, IQ1-100 Schneider LS 35mm
f/3.5 8 seconds ISO 1000
I like both systems and enjoy using them both.  Stay tuned for more. And as always, thank you for your comments and suggestions.



Saturday, May 13, 2017

Fujifilm GFX 50S

I’ve gotten questions regarding my thoughts concerning the GFX and my Phase One IQ1-100 and while I’ve answered them as they came in I thought I’d do it here as well.

I really like the GFX however nothing beats 100-megapixels the Phase One IQ1-100 produces.  Am I going away from Phase One? The very short answer is no, then reread the previous sentence.  Granted, the more I use the GFX the more I like it however I don’t see it as a replacement; it is more of an additional tool.  Folks who use the Phase One XF with any digital back will readily admit to having a very heavy package.  Add a lens and you can quickly exceed 8 pounds.  Not so bad if you’re shooting off a tripod however there are times you need to have the XF around your neck.  Enter the Fuji GFX 50S which weighs considerably less.
Sunrise in Monument Valley
GF32-64 @64mm f/5.6 1/125 ISO 250
I’ve only had the GFX 50S since March 30th and hadn’t had the time to devote to using and learning the camera.  April brought us into the Monument Valley area for our annual anti-workshop workshop with Ken Doo Photography, Capture Integration, and Phase One.  While I had my complete Phase One kit I also had the GFX50S which was the camera I chose to shoot behind the scenes photos saving the Phase XF for more serious late on.  
Sand Dunes
GF32-64 33mm f/6.4 1/160 ISO 250
Monument Valley Overlook
GF32-64 @32mm f/16 1/125 ISO 400
I kept the 32-64 lens almost on the entire time wanting to have a lens offering a range of focal lengths.  I managed to sneak in a couple shots along the way showing the beauty of the area.  Thanks to Capture Integration, I was also able to give the Cambo CA-GFX a test run along with a Canon 17mm TS lens.
Cambo CA-GFX (cropped)
Canon 17mm TS
f/8 1/1000 ISO 200
Cambo CA-GFX 
Canon 17mm TS
f/8 1/1600 ISO 200
What I’ve learned so far:
Again, at the risk of sounding like a broken record; the more I use the GFX the more I like it.  I currently have three-lenses; 32-64, 64, and the 120 and have gotten a lot of use from all of them.  I’ve recently placed an order for the new 23mm lens.  
Cambo CA-GFX 
Canon 17mm TS
f/8 1/3200 ISO 200
The camera is very easy to use off tripod.  The viewfinder is bright and clear as is the rear LCD. I like the easy access to the ISO as well as shutter speeds and I’m currently have it set in such a way as to use the front wheel to quickly change the shutter speed and the rear wheel the f/stop.  I carried the camera around my neck for several hours without any strain.
What I don’t like is the stupid way the neck strap is connected to the body.  I’ve now gone through two-straps and each one suffer the same fate of twisting into a knot.  Once twisted you’ll need to spend a couple of minutes untwisting one end or the other until you have a usable neck strap.  While on the issue of the strap connector, they get in the way when changing the battery and when accessing the card slots.  The access problems are minor compared to the twisting of the strap.  Fuji, if you’re listening change the strap design.
Fence line
Near Shiprock Arizona
GF32-64 @ 32mm f/8 1/400 ISO 100
Wolf Annex near Winslow Arizona
GF32-64 f/8 1/250 ISO 100
It’s not all bad. I shot much more in one day than I normally would to the point I almost shot a compete 32GB card. I mention this to say I never ran out of battery.
Camp Ground
near Joseph City Arizona
GF 32-64 @ 32mm f/8 1/500 ISO 100
Cambo CA-GFX
The adaptor is small and light weight.  While connected to the GFX and Canon 17mm it added some weight however not overly so and remained well balanced. I like the idea of being able to attach the 17mm to a medium format camera and in doing so I got some stunning test shots.
However,  I have one issue with the adaptor I used.  The LCD is too dim. It’s so dim that I was unable to read the screen in bright day light. I tried to shield it with my body adding some shade and still could not read the screen. I had to walk back to my truck and either sit beside it in a darker shade or actually get in before I could see and read the screen. Unacceptable for landscape work. This is the main issue I returned the unit after only one-day deciding not to use it.  If Cambo fixes this fault then I’d highly recommend it for those who need/require super wide.
This is the result of 4-shots using a Canon 17mm shifting to the stops left, right, top and bottom. Near Mexican Hat Utah, f/8. 1/1250 ISO 100. Initial processing in Adobe ACR the Photoshop CC where it was stitched together and finally Nik Software before returning to Photoshop CC for final processing. The finished image measures 8192x9084 @300 for 74.4 MP.
Post Processing
I’d love to be able to process the GFX files directly in Capture One. Please, if anyone from Phase is listening do us all a huge favor. Since I can’t open the files in C1 I use Adobe instead.  All the images contained here were opened using Adobe ACR before sending then into Photoshop.  Some of the images also received a little help from either Nik Software or Topaz. I’d rather show images as a final product that I would use than the non-processed file.
GF120mm Macro
f/8 1/2000 ISO 2500
How well does the GFX 50S handle low light? The following is just an example.  The image was processed just to the point of showing the silhouettes.  
Where do I go from here?
I keep learning the camera. I’m still learning the manual focus function while using the 120 macro.  I’ve also started using a WACOM Mobile Studio which I’ll address soon.  The Phase One gear is resting until the end of the month when I’ll be back outside capturing the milky way over an abandoned ranch house.
Stay tuned for more and as your comments, questions and suggestions are always welcome.