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GF1-IR, take 2

Jack

Sr. Administrator
Staff member
Any reason why that camera would be harder to convert than a GF1?
Hi Amin:

I'll save you the read through the other thread where I was the guinea-pig for the GF1 conversion. Bottom line is Panny added IR blocking to the dust shake glass in the GF1 and it has to be removed in the GF1 conversion. Apparently this was not the case in the G1. Of course this means we've lost auto clean in the GF1, so we're back to canned air or swabs if you get goop on the sensor, but for me, I pretty much leave the kit 14-45 bolted to the camera and it hasn't been a huge issue yet. I'll probably blow it out daily on the Salton Sea workshop to prevent issues.

As for differences in the images, I doubt we could tell the difference between a converted G1 and a converted GF1 if the images were side-by-side.

So everybody is clear, I went with the GF1 for the reason I wanted my IR camera to fit inside a lens-slot in my MF bag so I always have IR with me. When the visible light goes to crap, the opportunity for IR expands my subject matter and shooting hours tremendously. And the G1 with the 14-45 on it won't make the MF lens-slot, but the GF1 with 14-45 will...
 

Amin

Active member
Thanks, Jack. I don't worry much about dust. I lived happily with dust on a Canon 5D for years, and as you said, sensors don't come much easier to clean than the ones in MFT cameras.
 

DHart

New member
When the visible light goes to crap, the opportunity for IR expands my subject matter and shooting hours tremendously.
Jack... this comment opened my eyes to something I hadn't even thought of... that capturing images with IR light would be less dependent on visible light. So I take it that IR captures after sundown don't require as much increased exposure as regular captures do?

And another thought occurred to me... IR captures can be enhanced in tonal range through exposure blending just as regular captures can, right? Have you tried blending any IR brackets? I would guess that might yield some particularly stunning results.
 

ustein

Contributing Editor
So I take it that IR captures after sundown don't require as much increased exposure as regular captures do?
Don't think so. If I understand Jack right he means the following:

1. Overcast often nice for normal photography not that good IR

2. Harsh noon sun is bad for normal photos and can be good for IR
 
V

Vivek

Guest
Don't think so. If I understand Jack right he means the following:

1. Overcast often nice for normal photography not that good IR

2. Harsh noon sun is bad for normal photos and can be good for IR
Sorry if this sounds confusing.

Harsh noon Sun isn't all that great for IR either. Once (another thread another camera), Jim Collum answered a question of mine by saying that he does not take a camera out (at all) when there is direct, harsh Sunlight. There was a ton of practical experience/wisdom packed in that seemingly simple reply.

From Jack's images (M8, MF backs) earlier, I would say that he meant the evening light around a sunset.

There are quite a few enchanting images from one of the earlier workshops (with an M8) shown.
 

pellicle

New member
Jack

pardon the late entry

excellent stuff. I'm not really a false colour guy, but when my last brick of HIE goes into the soup this will be where I'm going.

its also nice to note there were no optical center halo effects which some lenses cause

great to see
 
V

Vivek

Guest
Uwe, I would freely admit that I have little experience with landscape shooting (I have little interest as of now, yet. But that is besides the point).

What I do know is that, under IR (ie when proper tools are used), contrast is higher than normal, visible light. This creates massive problems, especially when dealing with skin tones and surroundings (urban structures). If you want to show sunlit grass, skies with no clouds and some urban structures in one frame, harsh sunlight is not the one I would prefer.

Of course, with post capture manipulations, the story could be re-told in many different ways. :)
 
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DHart

New member
Perhaps, then, bracketed IR exposures, blended, can allow IR to create stunning results under conditions which might otherwise have been considered undesireable? I've never heard of blended IR exposures, but the concept intrigues me anyway.
 
V

Vivek

Guest
Perhaps, then, bracketed IR exposures, blended, can allow IR to create stunning results under conditions which might otherwise have been considered undesireable? I've never heard of blended IR exposures, but the concept intrigues me anyway.
That calls for a different approach. Either don't take the camera out on a harsh lit day or blend it like you wish after wards.

Either of them are applicable to any type of shooting (Visible or IR).

Harsh light:



Cloudy, overcast light with approaching storm:



Both using a converted Nikon D80-IR (Hoya R72 filter over the sensor) and a kitzoom.

The sunlit image starts to show cracks (grain in shadows and abrupt transitions) when enlarged. Both images have minimal post capture work (curves and contrast).
 

Jack

Sr. Administrator
Staff member
Hi All,

I'll respond to the above 6 or 8 comments en-masse.

DHart and Vivek, Uwe is more correct in what I was meaning.

Jim Collum's philosophy is vastly different from mine on this topic. Jim likes soft, flat light, and when the light's like that, he won't stop shooting even to eat -- seriously! However, if the Sun is out in full force, he will often ride in the car and never pull more than his cell phone camera out to shoot. As a matter of fact, I was joking with him about this very thing the other night. This is also not to say Jim is wrong and I am right, but more an example of differing philosophies on photographing. In this case, harsh light simply does not have anywhere to fit into Jim's artistic style. I on the other hand, am not so easily discouraged by it. But then Jim does what he does very well, and his style clearly comes though in every image he posts and maybe I could learn a thing or two from that...

For IR, I feel you get more dramatic false-color effects in the pre-dawn light or under heavier overcast shooting conditions. In the beginning this is what I was after for IR and why I limited my shooting to those times. Mid-morning through later evening, assuming it's been a sunny day, the IR (heat) lingers in everything, so you do not get the same effects as you will in the early morning as everything has an abundance of IR.

However, during harsher direct daytime light, I feel you can still make interesting IR images. These tend to be the really high-contrast monochrome as there is so much IR present it pretty over-powers the slight bit of color needed for false color -- as in Vivek's example above. Though as can be seen in my full-color images earlier in the thread, at least with this last GF1 conversion, a tiny bit of color hangs in and can be put to interesting use too. All that said, I think straight, harsh Noon light with no clouds in a sky, make for pretty boring images. If one wants to shoot, this is the time for longer lenses and isolations whether you shoot for normal color, monochrome or IR. Invariably though, at least for me, since this type of shooting is usually about capturing shape, form and textures, so this is when my color captures typically get converted to monochromes... What's new for me, is this is also a time when I now am beginning to see and think in monochrome myself. So when that happens, IR can be more interesting than normal due to the inversions and juxtapositions of normal tonal values.

Finally, having a tiny camera all ready to go, makes it convenient to shoot IR and hence I do more of it. With the M8, I had to want to shoot IR bad enough to take the time to screw the IR/UV cut filter off and screw the IR pass filter on, and I am admittedly lazy enough I usually wouldn't bother expending that simple effort to try it. Having a little, dedicated camera all primed and ready to go has changed that for me.

As to HDR blending, I do not see it for IR. Bottom line is even in harsh light, the band is so narrow I almost always have a complete histogram to manipulate, so HDR would be kind of pointless.
 
V

Vivek

Guest
Excellent summary, Jack! :thumbs: :)

Great example of what an adult site with mature discussion can do to disseminate useful information in a friendly way!:thumbs:
 

Jack

Sr. Administrator
Staff member
Thank you Vivek, that's what it's all about IMO, sharing information :). FWIW I like BOTH of those images you posted very much, and they're perfect examples for what I wrote above!
 

pellicle

New member
Ok it is a least my take. All of these images:

http://forum.getdpi.com/forum/showthread.php?t=14187

were taken between 8:45am and 3:30 pm. We had often sunlight with clouds.

This image shows how IR records sunlight and shade:
just curious ... film or digital

if digital blended exposures?

HIE so far has given me pretty good capture range, Australia (when I go home) has much starker contrasts so I will be interested to see how well a digital goes. I have a coolpix 990 awaiting conversion as my preview / lightmeter camera

dam shame there ain't no 4x5 sheets in this anymore, but that's another forum

:)

PS

perhaps even there it might be ok ... this is a quick test done with a coolpix 950 a few years ago



histogram seems to be acceptable
 
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F

firefox23508

Guest
Greetings Jack, new to this forum but have been a member of the IR website for a few years.

I have a question for you regarding your GF1. I have a Panasonic G1 I have been planning on having converted. When I had my Canon Rebel XT converted by LifePixel a few years ago, I noticed some front/back focus issues on different lenses--caused no doubt by the fact that IR focuses on a slightly different plane than visible light. Even though that was supposed to be compensated for in the conversion, it was not perfect for a gamut of lenses (LifePixel claims to have corrected focus to a standard 50mm lens and I have no reason to doubt that, but it was not accurate for all lenses).

My understanding is that IR converted micro 4/3's cameras are immune to this focus problem because focus is achieved on the sensor in live view regardless of the autofocus lens used. Can you confirm this? Have you noticed any focusing irregularities with your camera and lenses?
 

DHart

New member
As to HDR blending, I do not see it for IR. Bottom line is even in harsh light, the band is so narrow I almost always have a complete histogram to manipulate, so HDR would be kind of pointless.
Jack... thanks for all the info!

So, you're saying that the tonal range of IR light is so narrow that with a single exposure you can comfortably capture good detail in both deep shadow areas as well as bright highlight areas? Put another way, increasing exposure beyond a given "midpoint" doesn't really get you any more shadow detail and decreasing it doesn't yield more highlight detail?
 

scho

Well-known member
I found this thread on calibrating raw histograms and WB:
http://forums.dpreview.com/forums/readflat.asp?forum=1041&message=33213571&changemode=1
Works very well for generating a calibrated target for setting WB with IR converted cameras. Basically, just create a new document in Photoshop with white background in RGB mode and set fill to R162 G64 B104 (tweak for your monitor) to get a magenta screen that will produce a neutral WB in camera. Use the screen display (full screen mode) as your target for custom white balance setting. If anyone has already used this procedure to generate appropriate "magenta target" RGB numbers for a nice warm/neutral result with the G series sensor let me know. My default custom WB is a bit on the cool side and I'm looking for a way to warm it up in the mids a bit. Also note that LR, ACR, and perhaps other raw processors will truncate color temp WB settings at 2000 and muck up your nice custom WB setting. RAW Developer (and I think C1 also) do not do this. Wish Adobe would get this fixed.
 

Jack

Sr. Administrator
Staff member
FWIW, posted a few more GF1 IR's in the IR thread. Here are a couple of them:



 

Jack

Sr. Administrator
Staff member
Greetings Jack, new to this forum but have been a member of the IR website for a few years.

I have a question for you regarding your GF1. I have a Panasonic G1 I have been planning on having converted. When I had my Canon Rebel XT converted by LifePixel a few years ago, I noticed some front/back focus issues on different lenses--caused no doubt by the fact that IR focuses on a slightly different plane than visible light. Even though that was supposed to be compensated for in the conversion, it was not perfect for a gamut of lenses (LifePixel claims to have corrected focus to a standard 50mm lens and I have no reason to doubt that, but it was not accurate for all lenses).

My understanding is that IR converted micro 4/3's cameras are immune to this focus problem because focus is achieved on the sensor in live view regardless of the autofocus lens used. Can you confirm this? Have you noticed any focusing irregularities with your camera and lenses?
Welcome to GetDPI! While I cannot confirm for 100% that focus is achieved directly off the sensor, I suspect in fact that it is. The reason for this is all of my Panny m4/3rds lenses focus perfectly on this camera. However, Precision warned me that doing the 665 nm conversion leaves enough visible light coming through that infinity focus cannot be achieved with the wider lenses as part of the conversion process lengthens the distance between the sensor and the lens flange. Obviously this isn't a problem for the heavier IR band as it has a longer flange focal than visible -- that was the primary reason I opted for the 715 nm conversion.
 
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