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A700 IR capabilities?
Topic Started: Nov 11 2007, 09:26 AM (517 Views)
rOnGrEn
Alpha Elite Member
took some impromptu IR shots to test if A700 can take IR pictures, any other bros tried out liao?

Posted my "observations" in the other forum but things seem to be moving slow as i still dun see any reply. Perhaps KM/Sony people dont check IR sub-forum. So post here hope more bros will comment or try out their A700. Hope we can find a good setup for A700 that can take IR photos..

I found that IR light is very much blocked for the a700... the same scene, same aperture (f/4.5) and same iso (iso400) took 2.5 seconds on the KM5d, and but 13 seconds on the a700!!

Both using kit lens, hot spots wise, a700 is much better than the 5d... And comparing lens, kit lens produced less hot spots than Tamron 17-50mm.

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rOnGrEn
Alpha Elite Member
I am still quite a noob to IR.. So don't know how to PP correctly.. just ran it through a downloaded Action. Here are the photos for comparison:

1. KM5D + kit lens
Posted Image

2. A700 + kit lens
Posted Image

3. A700 + Tamron 17-50mm
Posted Image
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rOnGrEn
Alpha Elite Member
As the hotspots are in the middle, the scene above (in pic 1 2 3) might not be so good to judge whether there is hotspot..because different parts of the scene have different brightness..

So I took a picture of a more "average" scene.. can actually see the "gradient" in tone.. but note that this time, the focal length is 70mm. Thus the effect of hotspots might be different.
4. A700 + kit lens
Posted Image

Heres A700 + kit lens at 18mm again. So is there hotspots problem? the photos for A700 were all shot at f/4.5, and hotspots tend to be more obvious at smaller apertures. But stopping down on the a700 would mean a terribly long exposure.. -_-"""
5. A700 + kit lens
Posted Image

Looks quite acceptable to me. Just wondering how come the leaves turn out red for all the a700 pictures.. haha.. What else do I need to do for the PP?
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yokechye
Member Avatar
Shoot for Passion, Passion to Shoot
looks like A700 can take better IR than 7D. but i see there are some red patches at corners and in the middle..
nevertheless, it looks decent enough to me
Story of 油菜
yokechyepictograph
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tankm
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Always Newbie
From the KM5D and A700, looks like A700 is brighter.

From what I heard, IR hotspot is due to lens design. Most lens does not take into consideration of the IR wavelength. Wonder if those older lens with IR marking will perform better ?

The last time I tried IR on the A100, after setting the white balance I switch to B&W mode. Have not tried it on A700.

TKM Photo Album

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yokechye
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Shoot for Passion, Passion to Shoot
tankm
Nov 11 2007, 08:43 PM
From the KM5D and A700, looks like A700 is brighter.

From what I heard, IR hotspot is due to lens design. Most lens does not take into consideration of the IR wavelength. Wonder if those older lens with IR marking will perform better ?

The last time I tried IR on the A100, after setting the white balance I switch to B&W mode. Have not tried it on A700.

oh is it... i didnt realised that it was lens design... always thought it was the sensor filter

ya considering the shutter used its fast when shooting with IR filter
Story of 油菜
yokechyepictograph
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rOnGrEn
Alpha Elite Member
yokechye
Nov 11 2007, 08:46 PM
tankm
Nov 11 2007, 08:43 PM
From the KM5D and A700, looks like A700 is brighter.

From what I heard, IR hotspot is due to lens design. Most lens does not take into consideration of the IR wavelength. Wonder if those older lens with IR marking will perform better ?

The last time I tried IR on the A100, after setting the white balance I switch to B&W mode. Have not tried it on A700.

oh is it... i didnt realised that it was lens design... always thought it was the sensor filter

ya considering the shutter used its fast when shooting with IR filter

yup lens design plays a part...

Look at the A700+ kit lens and the A700 + tamron 17-50mm...


I have KM17-35mm and Tokina 19-35mm too... but don't have 77mm IR filter so cant try whether these two lenses will be better.. hahaaha
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way2see
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Alpha Commander Member
Hi rOnGrEn...

I don't have the A700 so not much to comment... except that during one of my frequent searches online for Sony IR related sites/threads, I found 1 in dyxum.
Depending on your lens, A700 needs much long exposure than A100, just as KM 7D needs more than 5D.

Seems like the LPF for the A700 is blocking IR a lot more than A100.

I use the A100 for IR. Perhaps we can meet up and compare notes??
Posted Image
______________________________________________________________________________________________________________________________________________
Quiet please... Let the picture tell its story...
way2see.sg
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