I bought a hoya r72 filter, now i have no idea as to how to use it properly, nor do i have a lens that it fits yet, so i just hooked it over an old K series lens to see what happened. I tried to manually set wb but as i have never done this before i don't know if i did it right or not. Settings were 30 sec exp, f8 iso 400. I literally took 2 shots and thats it. Here they are. If you know what i should be doing or have any ideas please chip in. There is a staining issue on the sensor but im not worried about that at the minute, new to me camera is on its way.
I have just discovered that how I set the white balance was the correct method normally, it was incorrect for ir. I should have had the filter on to set it. That would have been difficult as the filter was just hanging on the end of the lens. I'll keep trying and post any results here. (Good or bad) I think tomorrow is supposed to be nice out so I might get a chance to try it. I have a feeling that subject matter, will be important to this type of photography as in contrasting colours that work well in ir, until I figure out different setting and stuff I will have to make do with what is on My doorstep.
Good to see you branching into another area - I look forward to seeing some IR stuff from you
I'm pretty much the opposite of an expert on IR, but I have dabbled too - I had dismal failures on my K5iis, but I read (on that thing called the internet) that the sensors in some of the older Pentax DSLRs would be better suited to IR, so as I have an *ist DS I gave it a try and the results were much better. I've still not been to take any proper shots, but the back garden provided some entertainment:
I don't remember doing any white balance setting, so hopefully I'll be able to learn a bit more from your adventures
Hi John, i have also looked on the interweb , and yes some of the older models are more suited, as the ir blocker that covers the sensor isnt as strong as some of the newer models and therefore will work better. Newer models can be used it just doesnt work as well. Have just checked the wb thing and to be honest it doesnt seem to make any real difference as wb can be sorted in ps anyway. Shooting raw is a must apparently, to be able to get the adjustments required. Bright sunshine is also good for this type of shooting. Just waiting on that pesky sun to come out to test this. That shot of yours worked out well.
I managed to get out to try a few more shots this evening, but just as I was getting back my alerter went off and we were called out to a fire. So back home now but no chance to see what the shots were like. I'll have to wait till tomorrow.
A quick test to see how likely it is that your camera can pick up ir is to set your camera to f11, iso 100, exp time 1 sec. Get a TV or other remote that has an ir bulb on the end and point it towards the camera while pressing a button and trigger the shutter. The bulb should show up bright. On K5 you can see the bulb is lit, but it's no where near being bright. ( bordering on over exp ), this should be a quick test to see how good your camera would be for this type of shooting. I might have to look at getting an older body if I want to explore this much further. Some of the compact cameras are easily modified so I might have a look at that option.
It's important to get the WB right in camera with IR. If you are going to do much IR its also worth making a camera profile. The easiest way to set WB is to point the camera at brightly lit grass wit the fliter on.. Older lenses tend to be better for IR as the coatings inside a lot of newer lenses cause internal reflections (hotspots).
If you are thinking of getting a converted camera my advice is get one with contrast-detection autofocus: that way you will have autofocus. I think the the K 01 would make an excellent IR camera; if I was still with Pentax I would probably get one converted
I suspect the 'sensor stain' is just flare, something IR is particularly prone to - mainly showing as a 'Hotspot' in the centre.
720nm filters like the R72 are mainly used for B&W whee the white balance is pretty much irrelevant. False colour IR is mainly the reserve of modified cameras with shorter wavelength cut filters (590nm is a favorite) but with unmodified cameras these will effectively just see the 590-700nm portion with the IR so attenuated that it wont be visible.
The tip with a TV remote is a good one, but using a 1s exposure is making things awkward. ISO 1600 & F4 on AV will also allow you to see the IR sensitivity.
I've not checked with a K5, but my old K7 is MUCH less sensitive than my K100d, (The k10d is also less sensitive than the k100). From what I've seen *InstD & K100 models are the best if you want to use an old camera, Another option which will give you MUCH more sensitivity is to get a modified camera where the hot mirror in-front of the sensor has been replaced with something letting IR through. I got a 'full spectrum' modified micro four thirds camera as I wanted to try out many different convertions & fitting a filter to a DSLR can make framing awkward. (An EVF show what the sensor sees even if its beyond the range visible to the eye). Converted cameras allow much quicker shutter speeds
To give you an idea of how the different options stack up have a look at my IR album on Flickr https://www.flickr.com/gp/petrochemist/t356e5 the first six where with the unmodified K100d, then six using 'nightshot' on a Sony V1 compact, followed by the converted GF1 with various filters.
Thanks for that guys, Jon, that a great link,lots of food for thought there and will definitely give it lots of thought. Mike, you have certainly gotten into ir shooting, that London pano is fantastic. either converting or getting a converted camera would seem the way to go as slower shutter speeds wont always work and you get the benefit of proper ir in that the ir isn't being blocked by sensor ir blocker. Lots to ponder and work out.
Cheers Steve, as you can see I know nothing about IR photography either But I am learning. Just realised the camera I was modifying was a sony h50 not h9. I really need to keep a look out for a properly modified camera, to be able to experiment with false colour. I will continue to update this thread as I go.
Ok so i managed to take a couple of snaps to try out the mod from last night, First shot is how night shot used to look, 2nd is how it looks now, 3rd is night shot plus r72 filter, hand held no long exposure, 4th is bw conversion, quick edit.