p.2 #2 · A thinner sensor stack may be possible after all!
Hello everyone,
Ilija from Kolari Vision here, I was the one working on the development of this. Right now we are using uncoated BG39 glass, our manufacturers have told us that coatings would not help delay the corrosion issues. The BG39 is more durable than the S8612 glass that had the recent corrosion issues. We have seen some issues crop up after a year or so of BG39 use in very humid climates, but so far in temperate areas we have not had any issues. I am working with our suppliers to upgrade the BG39 to a more durable highly humidity resistant version, but the time frame for that is unclear now, possibly much later this year. In the meantime, we will be offering a full warranty on the glass and free replacements (and upgrade, when it becomes available) if the corrosion issues ever crop up. Right now the conversion as well as the first real image results can be seen here. So far all tests have been done at much closer than infinity and we are still seeing significant improvements, even at smaller apertures, I am excited at what improvements might be seen with more telling tests.
p.2 #4 · A thinner sensor stack may be possible after all!
mdemeyer wrote:
I have a modified A7 on the way back to me and will post some before-and-after photos in a week or two as time and weather permit. WA lenses on-hand include Leica Elmar 24mm 3.8, Summicron 35mm (v4), and a Voigtlander 21mm Skopar (particularly bad on the unmodified Sony and really improves a lot with the mod). I'll also test other longer RF lenses but expecting less improvement there.
If someone in the San Francisco area with an unmodified A7 and/or other lenses wants to collaborate to broaden the testing set, PM me.
FYI, I was involved in the project (initiated it) but don't have any commercial interest in Kolari Vision, who is offering the modification.
Michael, I'm pretty much ready to pull the trigger and follow you into the wild. I've already emailed Kolar with some basic questions:
What precisely is the spec on the new filter cover? Part number if possible. What is the new thickness?
How is the new stack fixed over the sensor?
How will the new sensor cover effect auto WB?
How will it effect AF with Sony lenses?
Obviously the huge test will be on distant objects at infinity, and your 24SEM is perfect for that. I beg you to do some long shots with it WO, 5.6 and f/8 with details POF at least in one corner. That would be huge.
TY so much for all your work in this area. I was ready to just sell my A7, as I have M9, but if I can get it working, it would be nice to have as second body.
p.2 #6 · A thinner sensor stack may be possible after all!
Kolari wrote:
...Right now we are using uncoated BG39 glass, our manufacturers have told us that coatings would not help delay the corrosion issues. The BG39 is more durable than the S8612 glass that had the recent corrosion issues. We have seen some issues crop up after a year or so of BG39 use in very humid climates, but so far in temperate areas we have not had any issues...
Thank you Ilija for your answer!
I think a coating would help for the corrosion issue, but on BG 39 coatings have bad bonding to the glass - I suppose because of this your manufacturer hesitates.
p.2 #9 · A thinner sensor stack may be possible after all!
Romain, there are different optical workshops that have some stock sizes and thickness. It is relative unlikely to find a filter in the correct width and height and thickness, probably at some camera converting workshops. Edmund Optics is well known, but 3mm thickness is likely not what you want ;-) Präzisions Glas & Optik GmbH probably has better thickness on stock. Likely they also offer tu cut it down to the size you need. But prices for one piece are high.
For my interchangable filter project for my old Canon EOS Rebel XT I have cut some filters with a handhold Dremel tool, but to very low quality.
p.2 #10 · A thinner sensor stack may be possible after all!
My A7 is in the post to Kolari
I've taken a series of infinity test shots with the SEM21 "Before", WO 5.6,8 and f/11. Once I have the camera back I'll put a before/after set up in flickr.
p.2 #13 · A thinner sensor stack may be possible after all!
Just thought to mention that, if the rumors are true, Sony and Zeiss are filling the gaps very quickly with some fantastic looking glass, reducing somewhat the need to adapt RF glass.
p.2 #14 · A thinner sensor stack may be possible after all!
Here is SEM 21 @5.6, with LR corrections and mild pp on A7: SEM21_5.6_corrected by unoh7, on Flickr
If you really want to see the travesty, follow the cottonwoods below the mountain from center to edge.
Here is my "test shot", OOC from raw f/5.6: SEM21_5.6_OOC by unoh7, on Flickr
I may be crazy but I would expect the SEM21 to clean up a bit more with a thin cover than will the CV21/4, just because it's not a small lens like the CV.
Here it is next to the not-small ZM35/2 another candidate from dramatic improvement DSC04451 by unoh7, on Flickr
and the ZM18 another serious prospect, which could turn spectacular, here with a7: 2 roads by unoh7, on Flickr
not to mention the 28cron, here f/8 on a7r: cron_a7r_f8_ by unoh7, on Flickr
p.2 #15 · A thinner sensor stack may be possible after all!
rscheffler wrote:
Apparently Charles is sending in his a7R too... Looking forward to your before and after images!
You are right Ron I am sending my A7r on Monday, with FedEx so hopefully it will be only couple weeks return. My reasoning is the A7r will depreciate quickly after the release of the A9, so upgrading with the thin glass cover, this will open the possibility getting better performance from a whole range of M mount glass and extend the life of the A7r.
Charlie, looking forward to your comparison shots!!
p.2 #16 · A thinner sensor stack may be possible after all!
Charles, you are in a similarly high humidity environment as I live in I believe. I see where Kolari Vision state they will offer a free replacement warranty but they also note they have seen corrosion issues within about a year in high humidity environments. That does not seem like a long time before you might be sending the camera back for a fix. In any case, I'm very interested to see what sort of performance benefits you see.
p.2 #17 · A thinner sensor stack may be possible after all!
I figured this would happen eventually, and the geek in me wants to ship off my a7, which is just sitting in a storage cabinet waiting to become a digital back for a Cambo Actus this summer, as soon as possible. But the geek will have to be satisfied living vicariously through those of you going through with the mod. My complaints about the a7/r had nothing to do with their IQ when using the adapted lenses I want to use, and the a7II fixed my issues.
So if this works out well, will the only burr left in peoples' saddles be the compressed RAW?
p.2 #20 · A thinner sensor stack may be possible after all!
Tariq Gibran wrote:
Charles, you are in a similarly high humidity environment as I live in I believe. I see where Kolari Vision state they will offer a free replacement warranty but they also note they have seen corrosion issues within about a year in high humidity environments. That does not seem like a long time before you might be sending the camera back for a fix. In any case, I'm very interested to see what sort of performance benefits you see.
Jordan, yes you are right about the humidity. I did ask the question about warranty, and if I get 12 to 18 months before a new and improved replacement glass I will be very pleased. With the rate of new bodies arriving and improvements on the horizon I don't think this will be an issue.
With my M9/M240 bodies, I never had an issue with Leica with repairing any faults or issues, just the time factor of 2 to 3 months on average.
The M9/M240 always there were dust issues. Some you could clean yourself, but mostly for the serious cleaning I would leave to a Camera repair centre where they had the equipment and could do while you waited.
With Kolari vision, a quick turnaround to replace the glass is a great service, and with the view to new and improved thin glass covers, this will be interesting. It is more to take advantage of my existing M lenses, so the cost relative to what I have invested does not seem too bad. I am sure there will be varying degrees of improvements with different M lenses.
I do like to support Kolari with their efforts as Sony may take note and implement some of the improvements in their future models.
I had also spoken to Wayne from Camera Clinic in Melbourne, and they also do regular upgrades for IR for DSLR's. The problem here in Australia was the cost factor for doing smaller run of thin filter replacements.
