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GF1-IR, take 2

scho

Well-known member
Carl....what I don't understand is that in LR....the WB bottoms out at 2000K and there is a mild to strong magenta cast to the converted image (depending on time of day, etc.). It seems like you would get less color cast if you could go below 2000K.

In C1, the same image shows up with a WB at ~2350K and has little or no color cast.

Just the way it is, I guess.

Thanks again.....R
I don't understand it either. My files also have a color temp at about 2300K or so in C1 and look exactly as they do in the in-camera jpg preview - very close to neutral with the custom WB setting. ACR and LR take the same files and as you noted, just slam them down to the 2000K min with a slight magenta cast. I've asked about this on the Adobe forum but never got a response. Adobe did post a special tutorial describing a profiling work around for this issue with IR converted cameras and it sort of works, but is another step in the workflow and although the camera profile does push the WB color temp back up into a workable range for ACR/LR you still have to manually correct WB during raw processing.
 

Lisa

New member
Jack (or whoever else knows) -
I'm considering getting an IR-converted GH1. Is the sensor the same as the one in the GF1? Is there any reason to believe an IR conversion will work any less well on a GH1?

I use the 14-140 zoom lens - has anyone here tried that lens on an IR-ized GF1 or GH1 to check for hot spots or other problems?

Thanks,
Lisa
 
V

Vivek

Guest
Lisa, There are no indications that the GH1's NMOS sensor would behave any differently than that of the G1 when it comes to IR.

However, all GF1 IR converted (Precision) have no dust shaker left in them. So, it is possible that an IR converted GH1 will also be without its dust shaker.

No experience on the 14-140 for IR. I do not like the 45-200 for IR. Way too soft (a manifestation of the "hot spot", flare, etc). I would suspect that the 14-140 will behave very similarly to the 45-200.
 

Cindy Flood

Super Moderator
Still pretty low on the learning curve compared to others. I want to thank Carl Schofield for some very much appreciated workflow hints....and of course, Jack for his PS actions.

GH-1 (IR) + Hexanon UC 15/2.8

Converted in C1 with Jack's "false color" action

Looks very good, Rich.
 

Rich M

Member
Jack (or whoever else knows) -
I'm considering getting an IR-converted GH1. Is the sensor the same as the one in the GF1? Is there any reason to believe an IR conversion will work any less well on a GH1?

I use the 14-140 zoom lens - has anyone here tried that lens on an IR-ized GF1 or GH1 to check for hot spots or other problems?

Thanks,
Lisa
Lisa.....I am using a converted GH-1......just got it back last week from Precision. Apparently, it was the first one they did.

I am quite happy with it. I have used mainly the 7-14mm and several wide legacy lenses with absolutely no problems. I took a few pics with the 14-140mm, but only on the wide end. No hot spots to report.

Precision actually requests the lens you will be primarily using to be sent in with the camera for calibration.....I followed Cindy Flood's advice and sent in my 7-14.....I am glad I did.

It was great advice (thanks Cindy).

R
 
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DavidB

Guest
Newcomer to GetDPI here. But as some of you know I've been around digital IR for a while. Several years ago I was doing IR conversions commercially, but these days I'm happier back concentrating on actually making images.

Here's one of my favourite IR landscapes, taken on a PowerShot Pro1 with 715nm filter:


I'm currently waiting to get my Panasonic G1 back from conversion at Spencer's Camera & Photo with a clear "full spectrum" filter. I'll be using a variety of external filters on it: B+W 486 for "normal" images, and 720nm and 830nm filters for IR. This setup doesn't work for DSLRs, but with EVIL cameras is perfect.
Unfortunately the Lumix 7-14mm doesn't take external filters, but once the camera checks out with the 14-45mm lens I have plans to take on an Olympus 9-18mm (which does take filters).

I don't understand it either. My files also have a color temp at about 2300K or so in C1 and look exactly as they do in the in-camera jpg preview - very close to neutral with the custom WB setting. ACR and LR take the same files and as you noted, just slam them down to the 2000K min with a slight magenta cast. I've asked about this on the Adobe forum but never got a response. Adobe did post a special tutorial describing a profiling work around for this issue with IR converted cameras and it sort of works, but is another step in the workflow and although the camera profile does push the WB color temp back up into a workable range for ACR/LR you still have to manually correct WB during raw processing.
I wrote about this last year.
Using a custom DNG profile in LR/ACR is great for this. But note that most IR shots can use the same WB!
So once you've set the profile in the Camera Calibration tab and chosen an appropriate WB you can save these in a LR Develop Preset and quickly apply them to the relevant shots. In fact, you can save these as part of a new Camera Raw Default for both systems.
This works great if the default applies just to your modified camera (for example if the tuple of model/serial identifies that camera). Unfortunately ACR is not able to detect the serial number of μ4/3 cameras (I don't think they put it into the EXIF at all) and thus if you set a new default for DMC-GF1 it would apply to images from all GF1 cameras (unless the images already had XMP data: it's only used when things are being reset to default).

Where I'm using converted DSLRs where ACR can identify the individual camera this works wonderfully. Import the RAW files, and the hard work is already done! The WB I saved as part of the default is usually fine, although sometimes I will tweak it a bit to suit the way I want to process the image. There's no "additional step in the workflow".

Unfortunately resetting the Camera Raw Default isn't going to work well for my G1, as the filters (and thus appropriate DNG Profile) may differ from shot to shot. I expect to be making big use of LR's Develop Presets...
 

Cindy Flood

Super Moderator
Newcomer to GetDPI here. But as some of you know I've been around digital IR for a while. Several years ago I was doing IR conversions commercially, but these days I'm happier back concentrating on actually making images.

Here's one of my favourite IR landscapes, taken on a PowerShot Pro1 with 715nm filter:


I'm currently waiting to get my Panasonic G1 back from conversion at Spencer's Camera & Photo with a clear "full spectrum" filter. I'll be using a variety of external filters on it: B+W 486 for "normal" images, and 720nm and 830nm filters for IR. This setup doesn't work for DSLRs, but with EVIL cameras is perfect.
Unfortunately the Lumix 7-14mm doesn't take external filters, but once the camera checks out with the 14-45mm lens I have plans to take on an Olympus 9-18mm (which does take filters).



I wrote about this last year.
Using a custom DNG profile in LR/ACR is great for this. But note that most IR shots can use the same WB!
So once you've set the profile in the Camera Calibration tab and chosen an appropriate WB you can save these in a LR Develop Preset and quickly apply them to the relevant shots. In fact, you can save these as part of a new Camera Raw Default for both systems.
This works great if the default applies just to your modified camera (for example if the tuple of model/serial identifies that camera). Unfortunately ACR is not able to detect the serial number of μ4/3 cameras (I don't think they put it into the EXIF at all) and thus if you set a new default for DMC-GF1 it would apply to images from all GF1 cameras (unless the images already had XMP data: it's only used when things are being reset to default).

Where I'm using converted DSLRs where ACR can identify the individual camera this works wonderfully. Import the RAW files, and the hard work is already done! The WB I saved as part of the default is usually fine, although sometimes I will tweak it a bit to suit the way I want to process the image. There's no "additional step in the workflow".

Unfortunately resetting the Camera Raw Default isn't going to work well for my G1, as the filters (and thus appropriate DNG Profile) may differ from shot to shot. I expect to be making big use of LR's Develop Presets...
David, That is an amazing image.

There is an IR image thread under the "Images to Share" forum here. I hope more people contribute to the thread.
 
V

Vivek

Guest
I'm currently waiting to get my Panasonic G1 back from conversion at Spencer's Camera & Photo with a clear "full spectrum" filter. I'll be using a variety of external filters on it: B+W 486 for "normal" images, and 720nm and 830nm filters for IR. This setup doesn't work for DSLRs, but with EVIL cameras is perfect.
I have hacked a G1 and been using it for a month now. The reason "EVIL" works with various filters is the lack of filter induced focus shift (unlike in DSLRs).

Welcome to the 21st century! :)

You would find that B+W 486 won't cut it for the NMOS sensor. Its IR sensitivity is sky high.
 
D

DavidB

Guest
You would find that B+W 486 won't cut it for the NMOS sensor. Its IR sensitivity is sky high.
Thanks for the heads-up. Have you found a filter that works for you to cut out UV/IR on the G1?
 

scho

Well-known member
David, Welcome to the forum and thanks for posting your beautiful false color IR shot.

But note that most IR shots can use the same WB!
So once you've set the profile in the Camera Calibration tab and chosen an appropriate WB you can save these in a LR Develop Preset and quickly apply them to the relevant shots. In fact, you can save these as part of a new Camera Raw Default for both systems.
True, and that is helpful time saving suggestion, but it would be even better if ACR/LR didn't mess up the camera custom WB when importing the raw files. I find that even with a custom camera DNG profile with adjusted WB, files often need some additional WB tweaking. C1 is the only raw converter I've found that correctly applies the camera custom WB and usually there is no need for further adjustment. I prefer the LR workflow, but just wish it interpreted camera custom WB like C1.
 
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DavidB

Guest
Yeah, unfortunately the in-camera WB is outside the range that the ACR dual-illuminant DNG profile engine can cope with (below "2000" Temp). At least there is a solution available.

When working with your camera, how often do you set a new custom WB? I've found with most IR-modified cameras that once you've set a WB you tend to stick to that (and Auto WB in IR has never been good for me). In that case using a fixed WB in the ACR default shouldn't be a hardship.
However, I usually work with filters of IR cutoffs of either 715nm or 830nm. Filters such as 695nm and 665nm let in more visible light, and thus I suppose it's possible that you'd be wanting to switch WB around a bit more... (?)
 

scho

Well-known member
Yeah, unfortunately the in-camera WB is outside the range that the ACR dual-illuminant DNG profile engine can cope with (below "2000" Temp). At least there is a solution available.

When working with your camera, how often do you set a new custom WB? I've found with most IR-modified cameras that once you've set a WB you tend to stick to that (and Auto WB in IR has never been good for me). In that case using a fixed WB in the ACR default shouldn't be a hardship.
However, I usually work with filters of IR cutoffs of either 715nm or 830nm. Filters such as 695nm and 665nm let in more visible light, and thus I suppose it's possible that you'd be wanting to switch WB around a bit more... (?)
I also don't change the camera custom WB very often and yes, it fine for almost all situations. The issue I have is with the Adobe DNG editor adjusted WB, which I have not been able to adjust to match the camera WB and that is why I need to tweak in post. If you are using the procedure outlined in the Adobe tutorial to adjust WB, how do you decide on an appropriate color temp and tint adjustment? Do you just eyeball the target neutrals and watch the values as you push the sliders for temp/tint or do you adjust the temp/tint sliders to get specific, pre-determined values?
 

Jack

Sr. Administrator
Staff member
Still pretty low on the learning curve compared to others. I want to thank Carl Schofield for some very much appreciated workflow hints....and of course, Jack for his PS actions.

GH-1 (IR) + Hexanon UC 15/2.8

Converted in C1 with Jack's "false color" action

Very nice image Carl! :thumbs:

Glad to hear you're liking the little action set. Just to clarify, and I realize it's personal taste, but you can slide the hue slider left on that adjustment layer and get the sky more true blue if desired ;)
 

Jack

Sr. Administrator
Staff member
Jack (or whoever else knows) -
I'm considering getting an IR-converted GH1. Is the sensor the same as the one in the GF1? Is there any reason to believe an IR conversion will work any less well on a GH1?

I use the 14-140 zoom lens - has anyone here tried that lens on an IR-ized GF1 or GH1 to check for hot spots or other problems?

Thanks,
Lisa
Hi Lisa:

I will echo what Vivek said re the GH1 sensor -- while different, should not present any significant problem, but the folks at Precision are very good and will work with you to get it right.

As for the 14-140, it is a very decent lens and I only recall seeing slight and occasional hot spotting at the shorter focals, like 14 through 18 or so. Since that and the 20 primes ride on my color GF1, I keep the little 14-45 kit lens pretty much on my IR GH1 at all times. Regardless, the 14-140 hot-spotting isn't huge and probably will present only an occasional problem. I am thinking it actually may be more flare dependent than anything, meaning it shows up most when shooting wide toward a bight light source...
 
D

DavidB

Guest
On those DNG profiles I don't care what Temp/Tint values are reported (as long as they're not at their limits) as it doesn't have to match the behaviour of the profile for any other camera.

I've been happy with the results from ACR by themselves, rather than comparing to the JPEGs the cameras produce. The only reason I've changed the camera's WB is to get images that are representative of the final result (and with sensible histograms) but I did start out with a workflow where I would process them heavily through Photoshop and thus didn't expect a perfect match. The Photoshop action I made years ago is still useful, and can be downloaded from here. In the last year I've been getting images out of ACR with most of that work already done, and haven't expected a perfect match to the cameras' JPEGs.

Also most of my IR work has been in monochrome, although with the G1 I expect to dabble a bit more in false-colour work so things may change a bit for me.
 

Jack

Sr. Administrator
Staff member
Re C1 workflow. Seriously, it is so easy to do the IR raw conversions in C1 it is almost ridiculous. I set up a "style" that uses the camera's internal WB and applies my standard sharpening and NR settings. All I do is apply that style to the group of images and process them out. It would be candy easy to add styles for any other filtration, and in fact I have one for the GF1 with the 092 cut filter when used over the lens of my GF1 IR.

Anyway, once the C1 batch out is done, I load them into CS and run one of the 7 actions from my action set on them -- one false color and 6 various monochrome and partial monochrome treatments -- any of which are also easy to batch. Then it's a minor tweak to the Hue/Sat adjustment layer for the false color as needed -- though I have a Hue/Sat custom setting saved and have my action call that up automatically, so any further tweaks are usually not needed. Then a final tweak to the output curve layer to adjust global contrast as needed and I am basically done, except for any local editing that may be required...
 

Lisa

New member
Hi Lisa:

I will echo what Vivek said re the GH1 sensor -- while different, should not present any significant problem, but the folks at Precision are very good and will work with you to get it right.

As for the 14-140, it is a very decent lens and I only recall seeing slight and occasional hot spotting at the shorter focals, like 14 through 18 or so. Since that and the 20 primes ride on my color GF1, I keep the little 14-45 kit lens pretty much on my IR GH1 at all times. Regardless, the 14-140 hot-spotting isn't huge and probably will present only an occasional problem. I am thinking it actually may be more flare dependent than anything, meaning it shows up most when shooting wide toward a bight light source...
Thanks much, Jack! It sounds like it would work mostly OK. Now I just need to wait until one can buy a GH1 without the lens (since I already have one with the lens for color)...

BTW, I did some tests comparing similar photos of the GH1+14-140 with my previous camera, a Nikon D300 with the 18-200 VR DX lens, and it's very difficult to tell the difference in quality.

Thanks,
Lisa

P.S. To DavidB: I *love* the African IR photo. It's a fantastic subject, and the colors go with it well. Cool stuff!
 
V

Vivek

Guest
Have you found a filter that works for you to cut out UV/IR on the G1?

Short answer, is yes and no.

With a Baader Planetarium 2" fringe killer filter (pricey) and custom WB, it comes close but not there yet.

With the B+W filter you could try adding a cyan filter. BG39 and the like. I will check those combos shortly.

..and David, I look forward to your pictorial contributions! :)
 
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