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Breaking in the Sony A7R: Part One


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#1 Andrea B.

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Posted 27 March 2016 - 05:51

I've just gotten my new, full spectrum converted, 36-MP Sony A7R for UV/IR work. I'll be testing it out over the next couple of weeks to get everything configured for serious work this spring and summer.

Observations: I cannot review every feature of the already well-reviewed Sony A7R. So I am only going to mention what catches my attention as I prepare to use this camera for my UV work.
  • Sony A7R batteries are underpowered. I had bought 4 to start with: 2 Sony and 2 Watson knock-offs. I may need to get 2 more batteries. UV work makes hard use of Live View which eats batteries even when they are not underpowered. Because the A7R does not arrive with a battery charger in the box (why Sony why?), I also got a double-slotted Watson charger. That thing is huge! But I can already see that it will be heavily used. For added battery power, see next.
  • Battery grip: I got a 3rd party Vello 2-battery grip for $89 which is almost identical to the $298 Sony stock grip. Both grips feature repeats of the shutter button, off/on button, C1 button, AF/MF button and front & rear dials - all for easy use of the gripped camera in portrait mode. The grip fits into the A7R battery hatch whose door is easily removable using the door's release switch. When gripped, the monitor shows usage info for both batteries.
  • Setting custom WB in UV caused an error message most of the time. But the A7R still permitted me to save the errored UV-WB setting. My guess here is that the extreme low "temperature" required for UV-WB causes these kinds of error messages? However, the saved UV-WB seemed to be a good one as you will see.
  • Due to conversion (I suspect) metering is underexposing by 1-2 EVs outdoors in bright sunlight. This occured using matrix or center-weighted metering. Fortunately the physical EV dial is right under your thumb on top of the camera. I don't think this underexposure is a big deal. As I go along I will try to narrow down the role a particular lens or filter might have played in this initial observation.
  • The A7R has two memory banks available on the top mode dial. This is cool beans. Thank you, Sony. As soon as I finish working out the desired settings for the A7R in UV and in Visible light, I will save them in these banks for easy access while making photos. I typically have different ISO settings for UV vs. Visible along the lines of 400-800 vs. 100-200. And always have different white balance settings for UV and Vis.
Let me interrupt for a second: I like this nifty full-frame, full-featured A7R, so please do not let any minor negative observations dissuade you from giving it a try sometime. It is important to point out little difficulties as they arise and figure out work-arounds. Every camera system I've ever used has its particular quirks.
  • Focus peaking is really a mixed bag. It works quite nicely indeed for wide, landscape-y shots. It works less well for close work. Some subjects don't pick up the focus peaking at all even when in focus - flowers, for example. IMHO, focus peaking is not precise enough for medium-close to close work to skip using focus magnification on the LCD (see next).
  • Focus peaking works with dark UV-pass or IR-pass filters as long as you have enough UV or IR illumination, of course. I've been using aperture pre-set on my manual lenses to ensure this. Focus in Live View with the lens wide open, then stop down. As always a UV-torch is useful for focusing in UV. Remember that there can be focus shift between aperture changes. Once you know that, it is easy to compensate for if not covered by increased depth of field.
  • Use the stepped Focus Magnifier for better focusing capability. I configured the AF/MF center button to provide the Focus Magnifier. (The + button on Nikons provides focus magnification. On a Sony body you have multiple choices for placing this configuration.) First press brings up the focus rectangle for you to move around with the wheelie dial on the back of the camera. Second press magnifies. Third press magnifies more. Fourth press returns to the unmagnified view on the LCD.
  • Perhaps due to conversion (?) the in-camera white balance measurements seem slightly off?? This is just preliminary observation. There are so very many variables which contribute to WB that it will take some time and further practice to sort this out.

This photo was originally posted in another thread. From left to right:
Meritar 50/2.9, Isco 35/3.5, CZJ 60/4.0 UV-Objektiv, Vivitar 35/3.5, Sony Alpha 7R
Attached Image: sony_and_lenses.jpg
Andrea G. Blum
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#2 Andrea B.

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Posted 28 March 2016 - 17:26

Before I show you the boring colour profiling shots, here is a teaser from the A7R. Michael brought home a small Easter bouquet for me. Naturally I rushed it right outside for practice shots with the new gear.

I have not yet finalized the profiling I want/need to do, but I can see that things are lookin' good with the A7R in these preliminary shots. I am very pleased so far.

I'm showing you the converted, edited After before the Before 'cause I want you to see the good version first. But note that the Befores aren't so bad! :D

The following photos were highly cropped because the Vivitar wouldn't let me get too close. The crops represent only about 1/15 of the original photo area. The cropped photos were then resized for viewing here and jammed into an sRGB box. Amazing to me that they held up so well after undergoing all this!!


Equipment [Sony A7R-broadband + Vivitar 35/3.5 + Sunlight]
....and Color Checker Passport and Spectralon Standard


Visible [f/8 for 1/400" @ ISO-400 with Baader UV/IR-Cut Filter]

After Photo Ninja conversion.Highlights pulled back. Shadows lifted (maybe too much). Detail slider. Custom colour profile. Other minor edits.
Note: Like every other digital camera I've ever used, the A7R has minor problems with dark magenta/violet colours. This rendition is almost but not quite accurate, but you wouldn't know that unless you could see the flowers for reals. I should have pulled back the saturation a bit because I lost some recorded details in the dark pink flowers.
Attached Image: a7r_bouquet_visSun_20160326wf_165058pn02.jpg

Before SOOC JPEG.
Note: Still learning the A7R, so I do not yet have anything set in the camera to deal with highlights and shadows. This Before is overexposed by a bit. But if I were using the Sony in-camera DR setting, I might have gotten better shadows in this strong contrasty sunlight. There is too much yellow in the flower colours so the in-camera white balance was not quite accurate.
Attached Image: a7r_bouquet_visSun_20160326wf_1650580101.jpg


Ultraviolet [f/8 for 1/400" @ ISO-400 with BaaderU UV-Pass Filter]

After Photo Ninja conversion. Highlights pulled back. Shadows lifted. Detail slider. Visible custom colour profile applied, then white balance reset. Other minor edits. I could have added a tiny bit more saturation/contrast to improve these rather dull blues.
Attached Image: bouquet_uvBaadSun_20160326wf_043pn01.jpg

Before SOOC JPEG.
Note: This is really a pretty nice SOOC shot. I probably could have boosted the exposure by a bit. Takes a while to learn how to read the LCD in UV when breaking in a new camera. Exposure meters are always just a little off in a full spec cam when looking thru a dark UV filter. Stop down focusing doesn't help matters. There is a slight amount of magenta cast in the white balance.
Attached Image: bouquet_uvBaadSun_20160326wf_0440101.jpg

After before cropping.
To show you the scale of the preceding crops, here is the uncropped Visible "After" photo.
Attached Image: a7r_bouquet_visSun_20160326wf_165058pn01.jpg
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#3 Andrea B.

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Posted 29 March 2016 - 01:03

Here is one set of photos made to use in creation of a good colour profile or colour preset depending on the converter/editor of choice.

Setting an in-camera white balance with the A7R seems almost trivially easy as far as the mechanics go. But I was a little surprised at just how far the converted colours have 'drifted' in the sense that performing an in-camera WB does not fully restore the proper for the given illumination.

Equipment [Sony A7R-broadband + Carl Zeiss Jena 60/4.0 UV-Objektiv + Overcast Sunlight]
and Color Checker Passport and Spectralon Standard.

I had a rather grey day for this experiment, so I popped the ISO up to a speedy 1600 to support good hand-held shots.

The UV-Objektiv produces some chromatic aberration which I have not yet tackled when converting & editing.

Visible Spectralon Square [f/8 for 1/5000" @ ISO-1600 with EV+1.0 and Baader UV/IR-Cut Filter]
Visible Color Checker Passport [f/8 for 1/2500" @ ISO-1600 with EV+1.0 and Baader UV/IR-Cut Filter]

Before SOOC JPEG.
The Spectralon is underexposed but it is neutral. (The extracted JPEG version was measured with a Photoshop colour dropper.) The CCPassport looks nice enough until you compare it to the colour corrected version. Then it can be noted that the pink and red patches have moved towards orange, the violet patch has too much red and the blue patches are too light.
Attached Image: a7R_standard_visSun_CZJobjek_20160327wf_10172601before.jpgAttached Image: a7R_ccPassport_visSun_CZJobjek_20160327wf_10181201before.jpg


After application of Custom LIght colour profile in Photo Ninja with white balance taken from the Spectralon frame.
The Spectralon frame's exposure was corrected. The CCPassport shows considerable change on the pink, red, blue and violet patches after applying colour profiling. PN's Neutral +65 was chosen here although for visible conversions I somtimes move to Standard +65.
Attached Image: a7R_standard_visSun_CZJobjek_20160327wf_101726pnafter.jpgAttached Image: a7R_ccPassport_visSun_CZJobjek_20160327wf_101812after.jpg

Before & After Composite
The circular area shows the colour prior to application of the Photo Ninja Custom Light colour profile and choice of Neutral +65.
Attached Image: a7R_ccPassport_visSun_CZJobjek_20160327wf_beforeAfter.jpg


Ultraviolet Spectralon Square [f/8 for 1/10" @ ISO-1600 with EV+3.0 and Baader UV/IR-Cut Filter]
Ultraviolet Color Checker Passport [f/8 for 1/4" @ ISO-1600 with EV+3.0 and Baader UV/IR-Cut Filter]

Before SOOC JPEG.
Although the A7R gave an error message when performing an in-camera white balance under the BaaderU filter, I was permitted to save and store the results. Typically a converted full spectrum camera will produce CCPasport colours in tones of greyed-blues, grey and black prior to colour profiling. That seems to be the case here. There is be a tiny bit more red than green in these greyed-blues.
Attached Image: a7R_standard_uvBaadSun_CZJobjek_20160327wf_10132901before.jpgAttached Image: DSC0028901before.jpg


After application of Custom LIght colour profile in Photo Ninja with white balance taken from the Spectralon frame.
The greyed-blue patches have become more saturated. Now they seem to have just a tiny bit more green than red. (Also I increased the saturation slightly by choosing PN's Neutral +65.) I think the blues here are prettier than in my initial flower bouquet effort.
Attached Image: a7R_standard_uvBaadSun_CZJobjek_20160327wf_101329after.jpgAttached Image: DSC00289after.jpg
Andrea G. Blum
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#4 Andrea B.

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Posted 29 March 2016 - 14:09

Further Observations about the Sony A7R:
  • The A7R body is small but reasonably ergonomic. I had my piano playing husband with the muscular big fingers use all the buttons and he did just fine. The buttons and dials have a good feel. The outer wheelie dial might is prone to bumping when the body is hand-held. The front grip worked for both me and Mike. Front and rear rotating dials have click detents. Every push button has a click detent also. The body is very right-handed. The only button on the left is the Menu button on the back upper left.
  • Adapted older, heavier lenses may stress the front mount because of the added adapter? Only use over time will tell this tale. The Sony E-mount certainly looks well-made and well-fitted to the body.
  • Configurable buttons: There are 3 configurable buttons C1, C2 & C3. The MF/AF - AEL switch has a configurable button which can be set differently for each switch position. The wheelie dial's center button and bottom detent are both configurable. So there are at least 7 configurable locations in which to store settings. You just have to get those 7 settings memorized in order to be able to zip through settings changes while shooting. I'm working on it.
*************************************

LIGHT LEAK or FOGGING with a specific lens/filter combo (nothing to do with the Sony A7R): BaaderU + Vivitar 35/3.5

No need to worry about light leak through the A7R electronic viewfinder! However, as always, light leak or fogging in UV can be happen from a variety of other causes. Here's a check list:
  • Check adapter-mount fitting.
  • Check lens-adapter fitting.
  • Check lens windows, if any.
  • Check body battery bay doors and plug-in hatch doors.
  • Check lens internals for reflective parts.
  • Verify that any reflective ("shiny") filter does not interact with sensor or lens parts.
  • [Internal IR producing shutter monitors on some DSLRs.]
  • [On DSLRs add: Cover viewfinder.]
Equipment [Sony A7R-broadband + Vivitar 35/3.5 + Novoflex Adapter + Sunlight]
I was also using the Vello remote whose cord plugs into A7R Multi socket into the left-side, lower hatch.

Ultraviolet [f/8 for 1/400" @ ISO-400 with BaaderU UV-Pass Filter]
This is an extensive light leak.
Added later: This is a flare problem, not a light leak.
Attached Image: bouquet_uvBaadSun_20160326wf_041lightLeak.jpg


So, running down the checklist:
  • The Novoflex adapter to E-mount bayonet fitting seems tight with no gaps.
  • The Vivitar to Novovlex adapter T2-screw mount seems tight with no gaps.
  • The Vivitar 35/3.5 has no lens windows.
  • The open lower left-side hatch door? A subsequent test with the CZJ 60/4.0 and wide open hatch doors produced no light leak. So this problem is specific to the Vivitar 35/3.5.
  • A7R has no IR producing shutter monitor.
  • Only one thing left to test: filter/lens reflection problem.
I found a reasonably evenly lit area and tested the Vivitar 35/3.5 with 4 filter configurations.

The actual subject here is a black canvas set up against a table leg. When photographed in UV, scuff marks on the canvas show up as patchy light areas.


FILTER TEST 1: All looks good.
In this first test set, the window light illumination was from behind the camera. What is evenly distributed light to the eye turns out not to be quite so to the lens. But no matter, at the end of the filter tests I found what I was looking for. These were meant to be made at f/8, but in the first test set I stupidly forgot to return the preset aperture to f/8 after the set-up.

Unfiltered [f/3.5 for 1/125" @ ISO-6400 with no filter]
Attached Image: a7R_filterTest_noFilter_20160329wf_142928.jpg


top left Ultraviolet [f/3.5 for 1/2" @ ISO-6400 with AndreaU UV-Pass Filter]
top right Ultraviolet [f/3.5 for 1" @ ISO-6400 with U-360/2mm + S8612/2mm UV-Pass Filter Stack]
bottom left Ultraviolet [f/3.5 for 1/1.6" @ ISO-6400 with BaaderU UV-Pass Filter, Pink Side Out]
bottom right Ultraviolet [f/3.5 for 1/1.6" @ ISO-6400 with BaaderU UV-Pass Filter, Green Side Out]
Attached Image: a7R_filterTest_andreaU_20160329wf_142957.jpgAttached Image: a7R_filterTest_u360.2+s8612.2_20160329wf_143016.jpg
Attached Image: a7R_filterTest_baaderUpinkOut_20160329wf_143043.jpgAttached Image: a7R_filterTest_baaderUgreenOut_20160329wf_143058.jpg


FILTER TEST 2: Found the problem.
In this test set, the window illumination is at a right angle (perpendicular) to the lens axis. I remembered to set the preset aperture back to f/8. You will see the reflection problem begin to appear.

Unfiltered [f/8 for 1/60" @ ISO-6400 with no filter]
Attached Image: a7R_filterTest_noFilter_20160329wf_143154.jpg

top left Ultraviolet [f/8 for 1.3" @ ISO-6400 with AndreaU UV-Pass Filter]
top right Ultraviolet [f/8 for 2.5" @ ISO-6400 with U-360/2mm + S8612/2mm UV-Pass Filter Stack]
Attached Image: a7R_filterTest_andreaU_20160329wf_143212.jpgAttached Image: a7R_filterTest_u360.2+s8612.2_20160329wf_143234.jpg

And here it comes........do you see it on your monitor?
bottom left Ultraviolet [f/8 for 2" @ ISO-6400 with BaaderU UV-Pass Filter, Pink Side Out]
bottom right Ultraviolet [f/8 for 2" @ ISO-6400 with BaaderU UV-Pass Filter, Green Side Out]
Attached Image: a7R_filterTest_baaderUpinkOut_20160329wf_143255.jpgAttached Image: a7R_filterTest_baaderUgreenOut_20160329wf_143322.jpg


FILTER TEST 3: Confirmed the problem.
Now that I was beginning to see the reflection problem was caused by some interaction between the BaaderU and the Vivitar 35/3.5 lens, I wanted to make it worse. I turned the lens towards the light by about 30 degrees (rough estimate) from its position in Test 2. And indeed the problem worsened. The shiny BaaderU and the Vivitar 35/3.5 do not play well together.

Unfiltered [f/8 for 1/60" @ ISO-6400 with no filter]
Attached Image: a7R_filterTest_noFilter_20160329wf_143406.jpg

top left Ultraviolet [f/8 for 1.6" @ ISO-6400 with AndreaU UV-Pass Filter]
top right Ultraviolet [f/8 for 3" @ ISO-6400 with U-360/2mm + S8612/2mm UV-Pass Filter Stack]
Attached Image: a7R_filterTest_andreaU_20160329wf_143423.jpgAttached Image: a7R_filterTest_u360.2+s8612.2_20160329wf_143442.jpg

Now the reflection problem is more apparent.
bottom left Ultraviolet [f/8 for 2.5" @ ISO-6400 with BaaderU UV-Pass Filter, Pink Side Out]
bottom right Ultraviolet [f/8 for 2.5" @ ISO-6400 with BaaderU UV-Pass Filter, Green Side Out]
Attached Image: a7R_filterTest_baaaderUpinkOut_20160329wf_143458.jpgAttached Image: a7R_filterTest_baaaderUgreenOut_20160329wf_143514.jpg


Let's take all 6 of the shots using the BaaderU and pump 'em up with Auto Levels to better see where the reflections are causing a problem.
The left-hand shots are made with the BaaderU Pink Side out, as recommened.
The right-hand shots are made with the BaaderU Green Side out, which causes a worse reflection problem.
Again, please ignore the random light patchy areas which are just scuffs on the black canvas which show up brighter in UV.
Please expand your browser so that the fotos appear in three rows of two each.
From top to bottom: Test 1, Test 2, Test 3
Attached Image: a7R_filterTest_baaderUpinkOut_20160329wf_143043amp1.jpgAttached Image: a7R_filterTest_baaaderUpinkOut_20160329wf_143458amp2.jpg
Attached Image: a7R_filterTest_baaderUpinkOut_20160329wf_143255amp3.jpgAttached Image: a7R_filterTest_baaderUgreenOut_20160329wf_143322amp4.jpg
Attached Image: a7R_filterTest_baaderUgreenOut_20160329wf_143058amp5.jpgAttached Image: a7R_filterTest_baaaderUgreenOut_20160329wf_143514amp6.jpg


Unfocused snapshot, no edits, with light at 45 degree angle to lens axis: Vivitar 35/3.5 + BaaderU, Green Side out.
A lens hood might cure the problem?
Attached Image: DSC00582.jpg
Andrea G. Blum
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#5 Andrea B.

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Posted 29 March 2016 - 23:10

Now it is time to go make some UV photos with the new gear. I will post a Part Two later when I have gotten more experience with the Sony A7R.

**********

I'm always happy to receive information about any typos or errors and make the correction. Sometimes it is difficult to edit one's own writing.
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#6 nfoto

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Posted 03 April 2016 - 16:31

Did you ever manage to solve the light leakage issue?

#7 Andrea B.

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Posted 03 April 2016 - 20:01

Yes. The explanation is in Post #4. The BaaderU and the Vivitar 35/3.5 do not interact well. The BaaderU is "too shiny" and causes reflection problems. Bad with the Pink side out and even worse with the Green side out. Other UV-pass filters like the AndreaU or a U-360 filter stack work just fine in the Vivitar 35/3.5.
Andrea G. Blum
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#8 Jonny

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Posted 17 May 2016 - 08:49

Hi Andrea, I wondered if you could clarify the process you are using here so I can further understand it -

When you create the profile in vis are you then applying that to the UV images or are you creating a new 'UV' profile with the filter attached?
Also what is the difference between profile light source and profile camera sensor and which is it we should use?

I don't own any spectralon but I am going to make a PTFE/Alu white balance tool, which I hope will give me a close approximation to neutral

#9 Andrea B.

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Posted 17 May 2016 - 18:12

The visible colour profile corrects the visible colours in the converted camera when a photo is made using some kind of UVIR-cut filter such as the Baader UVIR-cut or a BG filter of some type. Colour profiling is necessary because white balance alone does not always fully correct colours. And also because the UVIR-cut filters of various types may not fully replicate the original UVIR-cut filter which was removed from the camera. However, note that the differences between a colour-profiled visible photo and a white-balanced photo may be extremely subtle in some cases.

It is only in reproduction work or documentary work that we begin to care about such fully corrected colour. Please note that there are additional factors in this kind of work which are not considered here. For example, you need to consider (1) end-to-end colour manangment (colour spaces) from camera through converter, editor, printer (2) light in which the document is to be viewed (metamerism) (3) device on which the document is to be viewed and (4) so forth.

For my personal Visible work such as the floral documentation shown here on UVP I make use of white balance and colour profiles and post online photos in the sRGB colour space.

****

For a UV photograph, the notion of correcting false colours is most likely moot. However, the practice has typically been to apply a white balance step made either in-camera or later in a converter. This UV white balance step is the key to a standardized appearance of the UV false colours. Bjørn and I choose to do this for our botanical UV floral signature photos so that results for the same flower will be similar over a differing range of equipment.

For one's own personal UV photo work, anything goes, and there is no requirement to apply white balance steps at all.

In Photo Ninja, after white balance has been applied to a UV photo, I have also been applying the visible colour profile so that the standardized UV false colours are also "corrected". Like anything involving UV false colours, this is simply my personal preference.

****

I hope that clarifies a bit what I do. I'm always happy to answer follow-up questions about anything which is not clear.

***

Added: A proper colour profile is typically made for each combination of camera + lens + filter when working with converted cameras and specialized UV/IR-capable lenses. With new modern lenses, colour profiling, as seen in Adobe Camera Raw or other apps, does not include the lens but usually does include information about the colour response at each ISO level.
Andrea G. Blum
Often found hanging out with flowers & bees.