03-30-2012, 09:50 AM
(This post was last modified: 03-30-2012, 09:57 AM by Brightcolours.)
Any lens with little or no barrel distortion will do. The focal length does not matter much, just the longer the focal length, the bigger the distance to the subject (painting) will have to be.
The Canon 50mm f2.5 macro is a lens often used for reproduction work, but is more ideal on a full frame camera. On a compact APS-C camera it makes a bit less sense, because with the crop factor the distance to the subject needs to increase.
Personally I have used a Tokina 12-24mm f4 , which has very little distortion, in the range of about 20 to 24mm. Here the distortion graph at 24mm:
![[Image: 24mm_distortion.png]](http://www.opticallimits.com/images/8Reviews/lenses/tokina_1224_4/dist/24mm_distortion.png)
I also have used the Canon EF 35mm f2, which also enjoys quite low distortion:
![[Image: 35mm_distortion.png]](http://www.opticallimits.com/images/8Reviews/lenses/canon_35_2_50d/35mm_distortion.png)
However, I have found it not practical to try and shoot many paintings perfectly straight both horizontally and vertically, it takes too much time to try align the camera perfectly for each shot. So I end up straightening out the paintings in a program for Mac OS X, called graphic converter. It allows me to select all 4 corners, and then automatically crops and straightens the painting part.
So, for me it works like this:
- Get a distortion free lens with not too long focal length (at the moment using the Canon EF 35mm f2)
- Set metering with partial/spot metering on a paper with 50% grey (or 15/18% reflective grey), in the light the paintings will be photographed in
- Set the custom white balance on a white paper, in the light the paintings will be photographed in (now both the exposure time and WB are set for many shots, exposing every painting correctly no matter if they are dark or light).
- Shoot the paintings as frame filling as I am comfortable with.
- After RAW conversion (if you shoot RAW), open the images in graphic converter to crop and straighten them
- Save file as new "source file", to be used for whatever future purposes.
You basically can use any lens as long as it has little or no barrel/pincushion distortion, and it should not have too long a focal length else you need too much room to photograph the items. The lens should be able to focus accurately.
If you do not have a huge space but only a few meters room between the paintings and you, you should consider more wide angle (since you mention 6 foot paintings, which is about 1.8 meters). For that, the Tokina 12-24 with its very low distortion can not be beat, I think.
For smaller work (you mention 12") a shorter macro lens like the Canon 50mm f2.5 macro I mentioned are better suited.
For inbetween stuff I use my 35mm f2, because it is quite suited (low distortion, sharp) and I happen to already have it.
The Canon 50mm f2.5 macro is a lens often used for reproduction work, but is more ideal on a full frame camera. On a compact APS-C camera it makes a bit less sense, because with the crop factor the distance to the subject needs to increase.
Personally I have used a Tokina 12-24mm f4 , which has very little distortion, in the range of about 20 to 24mm. Here the distortion graph at 24mm:
I also have used the Canon EF 35mm f2, which also enjoys quite low distortion:
However, I have found it not practical to try and shoot many paintings perfectly straight both horizontally and vertically, it takes too much time to try align the camera perfectly for each shot. So I end up straightening out the paintings in a program for Mac OS X, called graphic converter. It allows me to select all 4 corners, and then automatically crops and straightens the painting part.
So, for me it works like this:
- Get a distortion free lens with not too long focal length (at the moment using the Canon EF 35mm f2)
- Set metering with partial/spot metering on a paper with 50% grey (or 15/18% reflective grey), in the light the paintings will be photographed in
- Set the custom white balance on a white paper, in the light the paintings will be photographed in (now both the exposure time and WB are set for many shots, exposing every painting correctly no matter if they are dark or light).
- Shoot the paintings as frame filling as I am comfortable with.
- After RAW conversion (if you shoot RAW), open the images in graphic converter to crop and straighten them
- Save file as new "source file", to be used for whatever future purposes.
You basically can use any lens as long as it has little or no barrel/pincushion distortion, and it should not have too long a focal length else you need too much room to photograph the items. The lens should be able to focus accurately.
If you do not have a huge space but only a few meters room between the paintings and you, you should consider more wide angle (since you mention 6 foot paintings, which is about 1.8 meters). For that, the Tokina 12-24 with its very low distortion can not be beat, I think.
For smaller work (you mention 12") a shorter macro lens like the Canon 50mm f2.5 macro I mentioned are better suited.
For inbetween stuff I use my 35mm f2, because it is quite suited (low distortion, sharp) and I happen to already have it.