TP: Infra-red with exisiting A-mount cameras

This is a rather old thread, but I thought it might be worth bringing it up-to date a little, as the mirrorless cameras (e-mount) are very different to use for IR.

My A7ii was full spectrum converted on immediately after I brought it.
With mirrorless cameras there is no problem seeing through any filter that the camera can see through. The EVF shows what the sensor see's irrespective of if the eye can see those wavelengths...

IMO this very much improves the flexibility of converted cameras. I can stick a 860nm filter on the lens & the camera allows me to frame, focus etc just as it would with no filter at all. I can then switch to a filter that shows UV & again frame without problem.

So far I've used over 20 different filter types on my converted camera exploring combinations of visible & invisible light that can't be seen with a more restrictive conversion. I can the install a clip in behind the lens (UV/IR block) filter to restore relatively normal behaviour.

I'm not sure how hard IR converted bodies are to find.
So, when I bumped into one when looking for something else, I thought y'all miht want to know - posted to external links:
https://www.dyxum.com/dforum/uk-export-too-used-a7r-infrared-not-mine_topic139085.html

neilt3 wrote: Off memory , there's a couple of firms in the UK that do camera conversions , so availability isn't an issue . So if you've got a spare camera , contact one of them about a conversion . I've converted some of my own cameras to either full spectrum of infrared ( done a few for some friends too ) . I've done a few Nikon D70's and a few NEX 3's and 3c's . The NEX 3 I have is full spectrum do I can put any filter over the lens to determine what spectrum I'm shooting in , the 3C is 720nm . There quite easy to work on .

cool beans ... is there a thread in here showing the different results with each type (e.g. 720, full-spectrum, 900?)

ideal cameras/lenses to go for?
I saw a link awhile ago (fujifilm) on which lenses have hotspots and which don't

dCap wrote:    ... is there a thread in here showing the different results with each type (e.g. 720, full-spectrum, 900?) I saw a link awhile ago (fujifilm) on which lenses have hotspots and which don't

The LifePixel website (link above in my earlier post) has a very nice presentation of the looks of the different IR conversions options. Kolari (link above as well) has the hot spot lens data base for many, many lenses, listing ones that don't have a hot spot and those that do.

My (very very limited) understanding of hotspots is that is it "lens" and "aperture" and "sensor" specific ... so mileage may well vary.

I shot a few rolls of Kodak and Konica IR film back in the 90s when lenses had IR markings on them.

And I've had a 52mm Hoya R72 for about 10 years (still sealed) as a 'one day' try this again thing. So fast-forward to the benefits of digital (and more so mirrorless) and not the expensive guesswork of film! Gotta give it a whirl one day in 2021.

AS the Kolari lens hot sport database is concerned I would be reluctant with my applause. I did not do a thorough comparison with the Kolari recommendations - but one lens which I sold because it had such a strong hot spot (from wide open to stopped down) was the Zeiss Touit 12mm. It is listed as good performer on the Kolari site.

From my experience stopping down usually intensifies the hot spot - often from a mild one (which can be compensated in PP) to a harsh one. I would be amazed if there are lenses where this relationship is inverted.

It would be great to have information about the IR hot spot "behavior" of lenses at different apertures. The Kolari site is lacking that information.