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Is it possible to use Sony A7S Mark II for UV/IR?


Andy Perrin

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Andy Perrin

I've been thinking of upgrading to a newer camera body, and because my current body is a Sony NEX-7, I'm looking at others in the Sony lineup. Quite a number of them have the following alarming warning on LifePixel's website:

 

Note: The Sony A7S II uses an IR LED as part of the electronic shutter monitor. Once these models are converted to IR or to Full Spectrum, the internal IR LED will contaminate all images shot at exposures greater than 1 second.

https://www.lifepixe...mera-conversion

 

I am not quite sure what the "electronic shutter monitor" does, and whether there is some way of switching off/disabling this troublesome LED in software or hardware, or if it's totally necessary to camera function until all circumstances. Anyone know if this is an insurmountable problem or something that can be worked around?

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I have been eyeing this camera myself, but I have not heard this warning before. The A7sII does not even have a shutter in the traditional sense (merely a guard curtain,) so I don't know what a "shutter monitor" would be. It certainly sounds like a crippling problem if the offending device cannot be turned off.
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Not familiar with this A7 series camera. However, on some Nikons there is a 'shutter monitor' operating via an internal IR LED and this feature causes a lot of grief and issues for any work outside the visible range. I once gave up modifying a Nikon D3 due to this, as I couldn't avoid internal flare or image fogging.
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well I'll be.......!!!!

 

First time I've heard of this, but very important to know. And I must immediately update the UV/IR Stickies to include this info.

 

A shutter monitor is controlled by the camera's operating software. The IR Led is turned on to shine thru the open shutter onto a small sensor to measure the amount of time the shutter is actuated. For the Nikons having this kind of shutter monitor, we know that there is no way to turn it off. I think if there was a way to turn off an internal IR shutter monitor for either Sonys or Nikons, the conversion shops would be happy to advertise the fact rather than warn you off converting a camera which has one.

 

Kolari Vision lists the following Sonys as having the IR Led shutter monitor:

A7 II, A7R II, A7S II, A7R III, A9, A7 III (No! Do not convert.)

Linkie: https://kolarivision...red-conversion/

Interestingly, Kolari says that IR contamination happens for 30-second long exposures at 6400 ISO. But you will have to take your chances on that. I meself find it very difficult to believe that there would not be any IR contamination in shorter, lower ISO exposures made under UV illumination and filtration. That certainly happened with my old Nikon D700 conversion disaster.

 

I'm trying to recall whether anyone was previous successful at taping over (or simply removing) the contaminating IR Led back when we were discussing the Nikons which have this monitor. We had always thought that perhaps either taping or removing it would confuse the timing software and result in some kind of error. If anyone would know, it might be Dan L. at MaxMax.com.

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More IR shutter monitors found. Geez.......

 

Panasonic G85*, GH3*, GH4*, GH5*, GX7*, GX8*, GX85*, GX9*, GM1* (No! Do not convert.)

Linkie: https://kolarivision...red-conversion/

For the Panasonics, Kolari Vision notes this: Can be worked around in most cases by using the camera in silent mode.

So, again, you might be taking your chances there, who knows?

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The following gives an example of someone who did a DIY modification on a camera with such a system. I do not judge its applicability here. Follow such advice at your own risk!

 

https://www.nickspik...dak-aerochrome/

 

A dedicated UV conversion might get around the problem if the LED light is stopped by the sensor filter. But I do not presume to know.

 

Also: the A7 series does have a silent mode. This presumably parks the guard curtain open during shooting and disables the auto dark frame. Does it disable the LED? That is indeed the question. Perhaps some of the techs at MaxMax or Lifepixel know something...

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That is a very sweet IR Led swap. This is good to know. Thanks for this link!! (I will add this link to the Sticks also.) My first question is -- where do I get a SWIR Led and sensor which would fit the Nikons? Second question -- who could I get to do this swap?

 

Good question about the dedicated UV converson -- it's hard to know whether an internal UV-pass filter would successfully block all of the IR-Led output during a long exposure? We have managed to capture some IR leakage through most UV filters during long exposures (20 secs - 30 secs) unless they have somewhat thick IR blocking BG glass. (The StraightEdgeU being the exception amongst the named filters.)

And I worry there may not be enough room internally for thick filtration over the sensor? This is not to say that someone should not investigate a dedicated UV conversion, because it is likely to be a good (and only!) solution if you are wanting one of the shutter-monitored Nikons, Sonys or Panasonics for UV.

 

(I've never wanted a dedicated UV conversion because I didn't want to be tied to one particular peak like 350 nm or 360 nm. Although maybe eventually I'll try one.)

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Addition to preceding:

 

Andy, what camera you convert depends on what UV/IR lenses you have. The primary dependence is on your lenses' flange focal length - and that only if focusing to infinity is a need.

 

So, you have plenty to choose from even if certain Nikons, Sonys and Panasonics are not suitable. We have happy users of Pentax, Canon and Olympus conversions as well as conversions from the non-shutter monitored versions of the N, S and P lines. Think about your needs and propose a couple of choices and perhaps you can get some feedback from users of those models here.

 

I would surely like to get a handle on this IR-Led swap method and find someone willing to perform that! This is the first real solution seen to the IR-Led shutter monitor problem. I've always been fairly fearless about opening up a camera (in spite of my two disasters. :rolleyes: But I find myself reluctant to tackle IR-Led swapping.

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Andy, only if Nick is willing to start a business would he probably take on this kind of work. It's pretty tedious. :D And more & more I want to have conversions done by those shops which have a table for working dust free because over the years both Bjørn and I have had so many trapped dust disasters - even from the big retail conversion shops. (Forget what those tables with hoods are called.)

 

But we should write Nick and get some details on the IR-Led swap.

 

if only I were younger......lol......i might start a little business of my own.

 


 

Clark: Also: the A7 series does have a silent mode. This presumably parks the guard curtain open during shooting and disables the auto dark frame. Does it disable the LED? That is indeed the question. Perhaps some of the techs at MaxMax or Lifepixel know something...

 

Also I was wondering whether using the electronic first curtain feature on certain cameras could be permanently used. Does this work in Live View, for example? Let's all try to find some answers on this stuff.

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Andy Perrin
Well, I'm not sure how he FOUND the darn diode and detector within the camera, for that matter, it looks like a mess in there. But as far as SWIR replacements go, he probably just picked something out from Thorlabs' site. Edmund may also have them, but I haven't checked because their prices are usually even worse than Thorlabs'. However, the question is what kind of package is needed for this LED to fit in the same place as the original?
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In a Nikon, it is not hard to find the IR-Led and detector. I haven't opened a Sony so don't know about those.

 

Presumably you would measure the old Led and detector and aim for that sizing?

 

If you want to try modding a camera yourself, first get a "parts" body sold for cheapie-cheaps on Ebay. Practice opening/closing it until you are comfortable with seating and reseating ribbons and other connectors. Sometimes you also have to break and replace a drop of solder.

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Andy Perrin

Andrea, I mean the LED packaging in the sense of type - there are loads of kinds of packaging:

https://www.thorlabs...ectgroup_id=285

 

SWIR LEDs can be a little pricy and you would want to know which one before taking apart the whole camera, if possible, so you wouldn't have to make two trips.

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More IR shutter monitors found. Geez.......

 

Panasonic G85*, GH3*, GH4*, GH5*, GX7*, GX8*, GX85*, GX9*, GM1* (No! Do not convert.)

Linkie: https://kolarivision...red-conversion/

For the Panasonics, Kolari Vision notes this: Can be worked around in most cases by using the camera in silent mode.

So, again, you might be taking your chances there, who knows?

 

 

I have a full spectrum converted Panasonic GH3, I never had a problem with IR leakage so far (I use the shutter).

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Andy Perrin

Andy, what camera you convert depends on what UV/IR lenses you have. The primary dependence is on your lenses' flange focal length - and that only if focusing to infinity is a need.

 

So, you have plenty to choose from even if certain Nikons, Sonys and Panasonics are not suitable. We have happy users of Pentax, Canon and Olympus conversions as well as conversions from the non-shutter monitored versions of the N, S and P lines. Think about your needs and propose a couple of choices and perhaps you can get some feedback from users of those models here.

All my current lenses (Noflexar, EL-Nikkor 80/5.6, a couple of others) are for using with APS-C, so going to a full frame sensor will certainly affect the crop factor across the board. But as far as FFL goes, that's another reason I thought I should stick with Sony. Unfortunately they seem to have made it difficult. I thought the Nikkons looked REALLY big and heavy for my tastes, and I would like to remain mirrorless.

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Look into Olympus or Canon. Or one of the older Sony NEX. Some of the older cams are still quite good. "-)

little edit: forgot canon is dslr and you want mirrorless.

 

The smaller Nikons like D5300 (or wherever the numbering has got to these days) are also a possibility.

FWIW, the EL-80 is quite fine over a standard size sensor. But methinks you probably have other considerations than just image circle size in wanting APS-C.

 

Andrea, I mean the LED packaging in the sense of type - there are loads of kinds of packaging.

Yes, got what you mean and Good Point. "-)

 


 

I have a full spectrum converted Panasonic GH3, I never had a problem with IR leakage so far (I use the shutter).

Werner, thank you for this comment. I was thinking that if Kolari Vision (or others) had put up a warning, then someone must have complained about contamination. But perhaps it was simply a "blanket" warning about Lumix models having IR-Led monitors? Hard to know without talking to the techs.

 

 

 

.

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Canon also have mirrorless cameras, the EOS M-series.

One nice thing if you already have Canon EOS DSLR-lenses, there is an adapter giving full functionality with those lenses.

 

I have one M1 awaiting a conversion until I get access to a cleanroom.

I do not know how the latest models are built , but the first one is built as a tank.

Astronomik.de sells suitable replacement windows to to replace the UV-IR cut filter if needed.

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Andy Perrin

Look into Olympus or Canon. Or one of the older Sony NEX. Some of the older cams are still quite good. "-)

little edit: forgot canon is dslr and you want mirrorless.

 

The smaller Nikons like D5300 (or wherever the numbering has got to these days) are also a possibility.

FWIW, the EL-80 is quite fine over a standard size sensor. But methinks you probably have other considerations than just image circle size in wanting APS-C.

I currently own a Sony NEX-7, which is APS-C, and I want to go to a standard size sensor. I like my NEX-7, which is an older cam, and was indeed quite good. But I feel like I'm ready to move on? I would dearly like better performance in low light. I take a lot of night pics, in visible and sometimes full spectrum. I wanted the A7S-II because it was rated highly for its low light pics.

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To add some more context to the subject... I also had (still have!) this problem with a full-spectrum-mod. After a number of attempts I was never able to fix the problem, and to this day it is a functional imposition to all of my images.

 

(OP here: http://www.ultravioletphotography.com/content/index.php/topic/1910-full-spectrum-mod-gone-bad/page__view__findpost__p__13266)

 

I would strongly recommend to avoid conversion of any cameras with this problem.

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Andy Perrin
Yeah, unless I can find someone willing to do the SWIR LED swap at the same time as the conversion then I think my dreams of A7s Mark II’s must die here.
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Andy, yes, that's a tough one then. A "good in low light" requirement together with a "mirrorless" requirement does limit your choices if cameras with IR-Led monitors must be excluded.

 

But there is the older A7S which does not have an IR-Led monitor (do verify!) and is way up there on the list for being good in low light. DxO Mark ranks the A7S higher than the A7S-II for good low-light capability. Now some folks quibble a lot over how DxO Mark does their measurements, but I've found that their rankings seem to hold up well enough in practice.

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I have converted a Sony A7S to full spectrum recently, it does pretty well in UV and IR, just like Andrea has said, A7S is actually a better low-light still camera than A7SII. A7SII has better video features, that's what the extra money is paid for.
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Andy Perrin

Considering that it is also a grand less, that sounds like very good news.

 

By the way, the specs list TWO sets of ISO ranges, one of which starts with 50. What does that even mean?

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https://www.dpreview...raw-compression

 

The only issue to be aware of is the unusual lossy raw compression in the first Sony a7/a7R/a7S cameras. You can read about it in the link above and try to determine whether it might ever cause a problem for your files.

 

Also note, for the record, that the MPs are: a7S = 12 MP, a7 = 24 MP, a7R = 36 MP. Unless you are printing a lot or wanting fine detail, the 12 MP should be enough?

 

edit: corrected typo.

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By the way, the specs list TWO sets of ISO ranges, one of which starts with 50. What does that even mean?

 

Not sure where you are seeing that? Is it a listing for video ISO versus photography ISO? Sometimes they are different. Or it could refer to the extended ISO range? That's where the native ISO is pulled/pushed in some way. In Nikons, for example, the pulled ISO is marked with an L and tends to clip highlights. The pushed ISO is marked with an H and is more noisy.

 

(Truth to tell I don't think I can define native ISO! Better go look that up. Aren't all ISO values over the base amped in some way? I think I'm no longer being helpful. :rolleyes: )

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