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Author Topic: KolariVision Astro-photography cover glass modification, Sony a7r (v.1 & 2)  (Read 2201 times)

Paul Roark

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Some readers of this forum may be interested in my use of the astro-photography cover glass to achieve better B&W landscape image files.  As with my pursuit of carbon based inks for B&W printing, I do not hesitate to modify the color-oriented OEM products to achieve better B&W.  At any rate, this astro cover glass modification is my latest attempt to improve my image files.  It is not for those who want the most accurate colors.

The summary of where I am with this is at http://www.paulroark.com/BW-Info/KolariVision-Astro-BW.pdf  .

(A similar post was made yesterday at https://groups.yahoo.com/neo/groups/DigitalBlackandWhiteThePrint/conversations/messages/109428 which is a mostly printing oriented forum.)

Paul
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roscoetuff

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New to some of this but trying to follow along - and frankly LOVING many of the B&W photos you've posted, I find the KolariVision material a tad bit obtuse.. especially with respect to the full OEM thickness cover glass. See no mention of it as a standard item so assume it is special order, or "by request only". But to be fair and not impose, I imagine I need to simply go back and try to fill in the rest of the story. THanks for the update!
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Paul Roark

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... See no mention of it as a standard item so assume it is special order, or "by request only"....

Contact Ilija at [email protected] .

Paul
www.PaulRoark.com
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roscoetuff

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In pursuing additional information, I stumbled on two alternative providers: http://www.spencerscamera.com/astro-filter-options.cfm and http://www.sciencecenter.net/hutech/prices/sony.htm

The first, Spencer Camera claims to have done Nikon conversions for NASA et al which while perhaps irrelevant to landscape photography and perhaps an accident of availability at the time, it's possibly "good advertising". And they provide a tad more explanation on what it is they're offering, the options, etc.  Yet none of these folks offers much guidance. Mostly, the inquirer is assumed to already have a pretty good idea about what they're looking for.

Guess the part that I find most interesting in this is how you came to the conclusion to use an Astro Photography conversion for standard B&W as I don't really see this discussed much. I'd suspect that one or the other of these providers was more forthcoming with the sort of support to encourage your path. Perhaps it's the Infra-Red B&W images seen from long ago that piqued your interest. Or maybe it's KolariVision's "Thin cover glass" conversion for Leica lenses that drew attention. In either case, the linked PDF is more of an account of some of the benefits and only teases the tech issues a tad. I found myself want to know more.

But perhaps you felt that discussion is better left for inquirers to have directly with the providers. FWIW, both seem to offer fairly similar solutions for a fairly broad range of equipment. Hutech is more interested than the others in actual astronomers... which isn't my bit. Like you, I'm drawn by the B&W possibilities, and would have loved a more direct comparison with the Leica Monochrome as well...as now I'm curious whether this might indeed be the sum total of the Leica engineer's own tech insight, and explain something of the higher price. Surely there's more than that, and folks are (always) ready to concede something magical to Leica, but it's curious whether there's more or not.

Comparing the offerings, KolariVision lists "Naked" and "H-Alpha" which corresponds to Spencer Camera's "Full Spectrum/Clear" and "Visible plus H-Alpha". Spencer also offers removal of the AA filter as well as installation of a "Heat Reduction System" but seems (without further inquiry) to offer these as mutually exclusive options. Implementation is always trickier, but with no sense that your interest included either Infra-Red or Astrophotography per se but simply a red spectrum enhanced B&W image, I'm betting you may opted for "Naked". Good guess?
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Paul Roark

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The www.Spencerscamera.com products look much like those from KolariVision, including the prices.  These outfits are probably getting the glass from the same suppliers -- Schott glass being my best guess as to the source.

I'd also guess that they are selling it "as is", which I found was not appropriate for at least some of the Sony and Zeiss lenses.  Note that long lenses, like telescopes, will not have any problems with the glass thickness.

I think I found my way to Kolarivision via some positive reviews on the internet.

My interest in the astro filter (visible light plus extended red for some specific spectral lines in astronomy) was due to my experience with Kodak Technical pan's similar response curve and its outstanding B&W rendition.  If I were to carry only one filter in the B&W film days, it would be a deep orange.  The astro conversion is a bit like having a very light red filter on the camera, though note that tungsten lighting is warmer when it comes to setting the white point.

I actually am not a fan of infra red B&W at all.  The astro filters give a very traditional B&W look, with, as best I can tell, improved red channel dynamic range.

It would be interesting to be able to compare to a Leica monochrome, but for me the ability to do the multi-color filtering in PS is too valuable to go the monochrome route.  I am rather confident that the Sony with the astro glass is a better combination for my type of photography.

I will continue to update my PDF at http://www.paulroark.com/BW-Info/KolariVision-Astro-BW.pdf as I gain more experience with this B&W approach.  It is obviously not what I would consider a "mainstream" approach, and I make no recommendations.  That said, after testing the astro cover glass on my "old" Sony a7r, finding the flaws in that thin filter, but also seeing the results, I opted to convert my newer a7rii with Kolari Vision's "thicker" glass.  Moreover, after testing that, I am not sending it back.   So, I obviously concluded that for my type of photography, this investment appears to be a positive move. 

Paul
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roscoetuff

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Paul: Thanks for your responses. One last question: Did you have your camera converted to "Naked", "H-Alpha" or something else - perhaps even custom? Thanks for sharing this.
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Paul Roark

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Paul: Thanks for your responses. One last question: Did you have your camera converted to "Naked", "H-Alpha" or something else - perhaps even custom? Thanks for sharing this.

H-Alpha Filter -- Filter with expanded spectral response that covers the H-alpha and sulfur II emission lines.

https://kolarivision.com/astrophotography-h-alpha-and-sulfur-ii-conversion/

If you go that route, be sure to be in contact with them about whether you want the "thin" (stock) version or the thicker version they put together for my Sony a7rii.  I assume they'll have that as a standard option at some point, but I don't know when.

See my PDF for more detials -- http://www.paulroark.com/BW-Info/KolariVision-Astro-BW.pdf

Paul
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roscoetuff

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My interest in the astro filter (visible light plus extended red for some specific spectral lines in astronomy) was due to my experience with Kodak Technical pan's similar response curve and its outstanding B&W rendition.  If I were to carry only one filter in the B&W film days, it would be a deep orange.  The astro conversion is a bit like having a very light red filter on the camera, though note that tungsten lighting is warmer when it comes to setting the white point. The astro filters give a very traditional B&W look, with, as best I can tell, improved red channel dynamic range.

It would be interesting to be able to compare to a Leica monochrome, but for me the ability to do the multi-color filtering in PS is too valuable to go the monochrome route.  I am rather confident that the Sony with the astro glass is a better combination for my type of photography.

Paul: Having now read a little of the hype, I have to admit it's hard not to join the Leica Monochrom borg... in fact, it's like resisting the gravity pull of a black hole. Almost feel as if you have to a rental "just to see". I'd done a Fuji X-Pro2... and didn't find the hybrid anything really special in my time with it. And fact is, I'm pretty much committed to the EVF way of shooting these days so I'm not sure a true rangefinder would fit. More, the Leica approach is not just tripple the cost of what I've got in my Sony/Zeiss combo, but as you mention, gives Leica control over the spectrum mapping. There's simplicity in that for sure, and some prefer it. I get that, too. Clearly, exercising control argues for the post-processing B&W solution over the Leica B&W shooting solution. Yet you seem to have mentioned using Leica lenses... and then opted for assuring usability of the Loxia 21mm. Begs the question on the glass. Glad to hear it by the way as an owner of... well, a collection of Zeiss Contax CY and Loxia lenses, and retention of color shooting as an option.... but wonder if you found the Loxia as sharp as it sounds. So I'm pondering all this and in the meantime trying to spend more B&W shooting time, and especially printing. The latter with B&W is really much more artsy where a little more time yields much more than it seems to do with color. Appreciate your commitment to documenting your path here, thanks!
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Paul Roark

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Paul: Having now read a little of the hype, I have to admit it's hard not to join the Leica Monochrom borg...

 I'm pretty much committed to the EVF way of shooting these days

...you seem to have mentioned using Leica lenses... and then opted for assuring usability of the Loxia 21mm. ... but wonder if you found the Loxia as sharp as it sounds. ...

I do appreciate the quality of Leica optics.  It was a major disappointment after buying into the Sony a7r platform that the normal and wide angle Leica lenses did not work as well as they did no my M9.  So, at that point I seriously considered the Monochrome.  However, the first Sony lens I had -- the 35mm f/2.8 -- was so good and compact that my distress of losing the use of the compact M wide angles was minimized.  All of the advantages of having RGB there even for B&W and the other state of the art aspects of the Sony made the decision rather easy, and I don't see me going back to a Leica body.  Although there is clearly room for improving the EVF, that method of through the lens viewing is obviously the best way to go for me. 

I had not given as much though as I should have to the impact of the cover glass that is on our digital cameras.  Any glass over the sensor is going to affect the image.  The higher the ray angle, the more the impact.  The move to the huge retrofocus designs like the Otus is one approach to solving the problem, but I greatly value compactness and weight. 

Until the first "thin" Kolari Vision astro filter conversion on my a7r, I didn't fully appreciate the extent to which the cover glass optical effects are incorporated into the modern Sony/Zeiss lens formulas.  Now I do, and that also answers the question of how they can make a compact lens that is so good.  There are, no doubt, limits and compromises in this approach, but so far, I have not seen them in my shooting.  So, the bottom line for me was that, with the *thicker* (contact the company directly) Kolari Vision astro (https://kolarivision.com/astrophotography-h-alpha-and-sulfur-ii-conversion/) filter, the Loxia 21 at f/2.8 gives me a better corner performance than the Leica WATE at f/4 when both are focused to infinity in the center.   

My favorite shot from this year's Golden Trout [High Sierra Wilderness, not fishing] Workshop -- http://www.paulroark.com/Campfire-MilkyWay-GTCamp-BW.jpg -- would have been noticeably better if I had been able to use the Loxia 21mm instead of the Leica wide angle Tri-Elmar (at 18mm, f/4, multiple frames).  As I said, that is the bottom line.

Paul
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roscoetuff

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If I understand it rightly, you've dropped the Leica in favor of the Sony. Do you still shoot Medium Format? or did you run out of Techni-Pan? Again, there's pull of the Leica mystique... and a ready Borg to join if you will, but I concede the temptation may have more to do with participating in "lore" than any real impact on imagemaking. Sticking with Sony's probably more rational for a host of reasons. Sometimes, I wonder whether the pull of the Leica has less to do with the wonders of the camera and more to do with managing the over-all size of the camera-lens combination. For my part, I share your affinity for Zeiss's Loxia line for just these reasons (undecided about the new 85mm given I've a nice Contax CY 85mm 1.4 about the same size).

Separately, I want to compliment you notes on red shift and focus on textured patterns for B&W images in one of the articles. Given me something to think about.
« Last Edit: January 13, 2017, 05:52:45 PM by roscoetuff »
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Paul Roark

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If I understand it rightly, you've dropped the Leica in favor of the Sony. Do you still shoot Medium Format? or did you run out of Techni-Pan? ... Sometimes, I wonder whether the pull of the Leica has less to do with the wonders of the camera and more to do with managing the over-all size of the camera-lens combination. ...

For most of my shooting, the Sony has replaced Leica.  I still use the Leica for a few things where accurate color is needed, since I converted the Sony to the extended red, astro cover glass.  I must say after getting used to the Sony, the M9 feels very "old school" and limited.

I don't use medium format film any more, though I've kept my Rollei SL66 and GX (TLR), mostly for emotional reasons, I suppose.  One of these days I'll go out with the TLR just for nostalgia reasons.

I had quite a bit of frozen 120 Tech Pan and sold it after being convinced digital full frame "35" had exceeded the medium format.  I must say, it's the only time I actually made money off selling old film.

The Leica M camera and lens compact sizes are major draws, but the quality of their optics is also very impressive.  In many respects, the company deserves its reputation for quality.  Given the extent to which digital cameras are electronics products, however, it's going to be tough for Leica to keep up.  On the other hand, one of the three lenses that went with me on my travels this last week was the Leica M 135mm.  You might be interested to see how that lens on the Sony resolves some of the moons of Jupiter: http://www.paulroark.com/Jupiter-30th-400iso-135mm-Apo-Telyt-at-100pc.jpg

Paul
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