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Rachel Foster
September 27th, 2008, 06:09 AM
I need a better camera. I do a lot of low light moody stuff and have had great difficulty getting sharp, clear images with the Rebel xti. This even with tripod, remote shutter, and good glass. I want to stay with Canon. In my situation, what would you go for? The 50d, the 5d or sell a kid and go for the 5d II?

Rachel Foster
September 27th, 2008, 02:03 PM
I did a publicity shoot for two local guitarists last night and really struggled with the lighting issue. Moving up to a 50 mm 1.4 portrait lens will help, but to get the sharpness I want I need a more light sensitive camera without question.

Mike Shimwell
September 27th, 2008, 02:30 PM
Rachel,

The 50 1.4 is not really that sharp wide open! It's OK at 2.8 up, but on a 50D your not likely to get great sharpness at 1.4.

I suspect that the 5D is likely a better performer than the 50D in low light if you consider noise, but the autofocus is probably better on the 50D - not sure but it's certainly reported to be an improvement. Low light af is a difficulty. (Having said that, Canon offer higher isos on the 50D, so perhaps it's really a big step forwards... perhaps you should try both in a store - make sure you underexpose some high iso shots.)

Of course, the alternative is to add light and then process to give you the look you want?

Mike

Charles L Webster
September 27th, 2008, 03:21 PM
Keep in mind also that your EF-S lenses won't work on a 5D. They will work on a 50D.

Does anyone know for certain that the 50D viewfinder is brighter than the 30D or 40D?

Rachel, are you shooting at high-iso and having trouble seeing the image to focus, or can you not achieve adequate exposure under the low light conditions?

Rachel Foster
September 27th, 2008, 05:44 PM
It seems to be more of a case of not getting enough light in. I am using auto focus, tripod and remote shutter and still not getting what I want.


I want as sharp as a finely honed blade.....

Charles L Webster
September 27th, 2008, 08:33 PM
The problem could be the autofocus. Generally AF doesn't work well in low-light situations.

What autofocus settings are you using, 1-point, all?

Manually focused, your EF-S 60mm Macro should be razor sharp at f4. Getting sharp at 1.8 or faster requires the application of many dollars.

Crop sensor viewfinders are never going to be as bright at their full-frame counterparts. But some are better than others. Sometimes a 3rd party focusing screen can help, I had a Katzeye screen in my 300D and it helped manual focusing, but only at larger apertures.

Rachel Foster
September 27th, 2008, 08:50 PM
I use center 1 point. Could that be the problem?

There was a noticeable difference when I finally got a l-series lens (24-105). I have wondered if that might be part of the problem. I've been considering a 100 mm 2.8 EF lens.

Asher Kelman
September 27th, 2008, 09:43 PM
I use center 1 point. Could that be the problem?

There was a noticeable difference when I finally got a l-series lens (24-105). I have wondered if that might be part of the problem. I've been considering a 100 mm 2.8 EF lens.
Rachel,

The center focus point, at least in the Rebel/XTi/Xsi series needs f2.8 lenses or wider to be activated fully. with the f4.0 24-105, that central accurate point is not activated, unfortunately. With the 50mm 1.4 or 1.8 the central point is always active.

Asher

Asher Kelman
September 27th, 2008, 10:07 PM
Rachel,

The 50 1.4 is not really that sharp wide open! It's OK at 2.8 up, but on a 50D your not likely to get great sharpness at 1.4.
The 50 1.4 is pretty sharp wide open but needs a tad of chromatic aberration correction, although not as much as the 50 1.2 L at f1.2-1.4. In general, Canon lenses are optimally sharp stopped down several stops from wide open.

I suspect that the 5D is likely a better performer than the 50D in low light if you consider noise, but the autofocus is probably better on the 50D - not sure but it's certainly reported to be an improvement. Low light af is a difficulty. (Having said that, Canon offer higher isos on the 50D, so perhaps it's really a big step forwards... perhaps you should try both in a store - make sure you underexpose some high iso shots.)
Mike,

It's likely that with digic 4, the 50D will deal with noise better. with smaller pixels, the 50d will simply image the diffraction aberrations from f8.0 and smaller. I expect the 50D will be one of the finest cameras and even the diffraction issues will likely not be seen in most 8x10 prints. So it all depends on what Rachel's needs are.

The low light issue of the 5D is not so much noise, (which does occur, and can be calmed with Noise Ninja), rather it's the poor ability to achieve focus in low light* especially with the f4.0 lenses but even with the Canon 50mm 1.2L!

Asher

*Here's a trick. Get the person to hold a spoon by their face just to grab focus on that. After that is locked, the pictures from then in will be spot on. I also will focus on something like that spoon on the table a foot from the face and then step forward 1 ft to take my perfect picture.

Rachel Foster
September 28th, 2008, 09:40 PM
I think I'm going for the 5d Mark II. In for a penny, etc.

I switched the focus points to automatic (instead of the center point) and think I got something a bit sharper. This was tonight, low light (ISO 400, 1/500, f/6.3, 24mm ... using the 24-105).

http://i183.photobucket.com/albums/x153/annieblues/opf/IMG_2305001.jpg

Yaron Lenard
September 28th, 2008, 11:29 PM
I have the 5D, and it is not great in low light. I have the 1Ds Mk III, which is considerably better, and I expect the 5D Mk II to perform equally well in low light.

Rachel Foster
September 29th, 2008, 07:13 AM
Thanks, Yaron. I do a awful lot of low light work.

Mike Shimwell
September 29th, 2008, 04:36 PM
Rachel,

Following Asher's comment I thought I'd shoot a few test shots with the 50 wide open and at high iso. Turns out that he was right, the lens isn't really bad at 1.4 after all!

Here are a few samples - I would expect the 5D2 to offer files at least as good as the Ds3.

Scene using 50 at 1.4. iso 1600 -1 stop = iso3200

http://farm4.static.flickr.com/3008/2900491426_9424e4353a_o.jpg

crop from 5D

http://farm4.static.flickr.com/3256/2899647301_b4afb930d3_o.jpg

crop from 1Ds3

http://farm4.static.flickr.com/3244/2899648215_3fa12d7d63_o.jpg

both have had some colour noise reduction in lightroom and sharpening, but no luminance reduction

And for comparison a crop from the 1Ds3 at iso100 with no NR or sharpening masj=king in LR, but with sharpening at 70, 0.5, 70

http://farm4.static.flickr.com/3161/2900493144_3aeef1a472_o.jpg

Mike Shimwell
September 29th, 2008, 04:42 PM
and at f2.8 (and iso 3200-1 = iso6400 for 1Ds3 as it's actually less sensitive than the 5D by the meter and the shutter speed was getting too low)

crop from 5D

http://farm4.static.flickr.com/3185/2899647627_126e19cf92_o.jpg

crop from 1Ds3

http://farm4.static.flickr.com/3205/2899648687_28bc4bf8ac_o.jpg

And just for fun, a crop from the 100 2.8 wide open at iso3200-1 on the 1Ds3. For some reason the light had changed at this point - maybe the computer had gone dark, but the image is noisier as a result.

http://farm4.static.flickr.com/3120/2899649219_a418e56186_o.jpg



Hope they're useful,

Mike

Rachel Foster
September 29th, 2008, 04:50 PM
NICE....but I just preordered the 5d Mark II through Ritz.


Gorgeous child, by the way, and nice images too.

Mike Shimwell
September 29th, 2008, 05:11 PM
NICE....but I just preordered the 5d Mark II through Ritz.


Gorgeous child, by the way, and nice images too.

I'm sure you won't be disappointed with the 5D2.

Thanks about the child, she's my youngest daughter experimenting with paint. I'm biased of course, but I think she's great.

Mike

Rachel Foster
September 29th, 2008, 05:13 PM
The photo that will be included in the Dow exhibition is mine....