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View Full Version : Got new stuff today (IR filter + 1.4x)


Longwatcher
18th of July 2003 (Fri), 23:30
This afternoon I finally recieved my IR filter to try out with the 10D. The filter is the Hoya R72 filter. I got the 58mm thread version.

jpeged example at:
http://www.longwatcher.com/images/CRW_2939-IR%20test.jpg

I used my 50/1.4
4 secs
ISO 400
f2.8
[trivia: image was resized to 640, downsampled to 72PPI, sharpened, then jpeged]

Looks fairly good. Unfortunately I was running out of sun as it had just set when I took this so I did not get any other good ones from the first run.

I did get a chance to compare with D60. Same lens. At same settings - way too dark. I had to go to 20 secs, ISO 800 and 1.4 to get to the same level as the 10D at the above settings. Same target, but different then one above. Most interesting, confirms that at least the ir filter on the sensor is different if not the sensor itself.

I also suspect that tomorrow when I play with it again I will need to put a UV filter over the Hoya filter as some of the UV seemed to leak through outside. Could be my imagination though, but the blue channel was brighter then the green. In any case, 10D work for limited IR against still life. D60 pretty useless.

On to the other topic.
Also received my 1.4x extender. Much better then 2x from first looks. Interesting trick. Put 1.4 behind 2x on 100-400L. Was not sure if it would work, but it fit and it focused (manually of course, which means I was off a bit as usual, plus the 2x is not very good in my opinion. However, It did get me closer to the target then just the 2x alone, so not sure if it multiples correctly, but it seems to work out as a cheap 1120mm lens with the 1.6x crop factor that makes a 1792 equivilant telescope. The below link should have all three images.

http://www.longwatcher.com/camera_test.html

In fairness, the aperture and shutter speed changed between shots, so these are probably not good images for seeing actual quality, just telephoto zoom scale. All three are 1-to-1 crops (downsampled to 72PPI, then jpeged, but not sharpened)

In short interesting. Which I could have afforded to get the other 2 IR filters I was looking at to see what those do. Maybe next time. At least I get to play with them this weekend.

Jeppe
19th of July 2003 (Sat), 04:09
Thats nice.. got to get me one of those R72's. :)

Also, yes i found that the EF 2x is pretty useless on zooms, i only use it with my 300/4L
Yes, when stacking the two EF extenders they will not report true aperture, you loose the data from the 2x (or one step from each extender). Also, for those who is interested, its only the version II of the extenders that can be stacked without a tube between.

Setup: 10D, EF 300/4L, EF 2x II, EF 1.4x II = 1344mm (35mm equiv.). 1/10, f11 (wide open)

http://www.fotosidan.se/obj/photo/m_3eb8b539f2c4b.jpg

Longwatcher
21st of July 2003 (Mon), 10:24
Although not posted, I took some pictures of girlfriend using the IR and having her hold still for about 4 seconds. It worked, but really tough to get focusing correct. I read somewhere that I needed to focus in front of the target and apparently this is correct. Seems like about 20% in front of the target. Tried several other pictures with interesting results.

I have decided that I am glad I did not get the other two filters as it makes for some interesting effects, but have decided the 10D IR range is not spectrally far enough out for more radical artistic images.

A note on the 1.4x and 2x mounted together. My EXIF data indicated it was ignoring the 1.4X so my guess is it is position dependent on which one it will read. Can't remember which on is where and forgot to test it out.

I love my 10D.