Sigma 1.4 30mm or 50mm

[realmike15]

I recently upgraded from a Rebel XS to Rebel T1i. I plan on sticking with this for a while, so I'd like to start my lens collection. First on my list is a nice Bokeh capable lens. After reading a few articles and knowing I want to keep my budget around $500... most people seem to agree the Sigma 1.4 50mm is the best 1.4 lens available for a Canon DSLR. I have a sensitive eye for pixelation and softness, and from what I read the Canon 1.4 can become quite soft in the 1.4-1.8 stops. I like to do a lot of shallow depth of field shot and odd shots that require me to get pretty close with the camera. I'm not saying I need to do macro close ups, but very often get very low to the ground or try to get odd perspectives that the human eye doesn't normally get to see.

Based on that info other than the focal length is there any difference between these two lenses? I was going to buy the 50mm but now that I saw the 30mm and saw that it's cheaper... I'm just wondering what the benefits are besides the focal length.

 

[Big Mike]

I'd suggest that the Canon 24mm F1.4 L and the 35mm F1.4 L are the 'best' F1.4 lenses for these cameras. Of course, either one is more expensive than your camera (and your $500 budget, put together).

The Sigma lenses do offer some great quality and a much lower price. That being said, there might be some issues with the Sigma lenses. Namely, AF accuracy. The 30mm F1.4 has a bit of a reputation for not being accurate...or at least, the QC isn't great and more than a few people have lenses that are out of calibration.

I've got the Sigma 30mm F1.4. It's probably the sharpest lens I own, when it's accurate...but I'm often too scared to use it at wide apertures because I don't know if they will be spot on or not.

They can certainly be calibrated, or maybe even returned if you get a bad one...so even if you actually have to pay for calibration, it's still a lot cheaper than a Canon 35mm F1.4 L.

 

[Dao]

The main issue will be the focal length. If you need a 35mm lens, you need a 35mm lens, and it should not be replaced by a 50mm lens.

i.e. Indoor birthday party photos. The space is tight. No matter how sharp the 50mm lens is, you may want to use a wider lens (shorter focal length lens)

Personally, I will not compare 2 lenses with different focal length (unless the focal lengths are very close)

 

[realmike15]

I'd suggest that the Canon 24mm F1.4 L and the 35mm F1.4 L are the 'best' F1.4 lenses for these cameras. Of course, either one is more expensive than your camera (and your $500 budget, put together).

The Sigma lenses do offer some great quality and a much lower price. That being said, there might be some issues with the Sigma lenses. Namely, AF accuracy. The 30mm F1.4 has a bit of a reputation for not being accurate...or at least, the QC isn't great and more than a few people have lenses that are out of calibration.

I've got the Sigma 30mm F1.4. It's probably the sharpest lens I own, when it's accurate...but I'm often too scared to use it at wide apertures because I don't know if they will be spot on or not.

They can certainly be calibrated, or maybe even returned if you get a bad one...so even if you actually have to pay for calibration, it's still a lot cheaper than a Canon 35mm F1.4 L.

Just to clarify, how far out of focus are you talking about exactly? I typically (90%) of the time will be in full manual mode for taking pictures. Most of my shots are setup and adjusted until I get the depth of field, perspective, exposure, and focus point I want. With my camera even in manual focus mode, when you start adjusting the focus, the focus points (9 of them on this camera) will blink when they're in focus. So if the focusing accuracy is only effected in Automatic mode... I think I'd rather have a sharper lens for the type of photography I'm doing, then worry about Automatic mode since I spend most of my time in manual anyway.

 

[realmike15]

The main issue will be the focal length. If you need a 35mm lens, you need a 35mm lens, and it should not be replaced by a 50mm lens.

i.e. Indoor birthday party photos. The space is tight. No matter how sharp the 50mm lens is, you may want to use a wider lens (shorter focal length lens)

Personally, I will not compare 2 lenses with different focal length (unless the focal lengths are very close)

I'm actually trying to figure out what Focal length I should start out with first... based on the information I gave in my original post. I'm not trying to make a comparison between which is better. I'm asking based on my needs, what's the best lens to start out with?

 

[Big Mike]

So if the focusing accuracy is only effected in Automatic mode... I think I'd rather have a sharper lens for the type of photography I'm doing, then worry about Automatic mode since I spend most of my time in manual anyway.

If you are waiting for the focus points to light up when manually focusing, then you are still relying on the AF system. I just skip that step and use AF .

Besides, with the rather small viewfinders on most of DSLR cameras, it's hard to judge precise focus. Especially when you're shooting hand held and your subject is not stationary.

As for how far it's out...it's not by much. But when your DOF is an inch or less thick, a little bit can make or break the shot.

 

[Dao]

If you have the kit lens, you may want to set the lens at 35mm and try it in different situations. Then do the same thing with lens set to 50mm. In that case, you roughly know what you will see in terms of Field of View with the 2 lenses.

 

[realmike15]

So if the focusing accuracy is only effected in Automatic mode... I think I'd rather have a sharper lens for the type of photography I'm doing, then worry about Automatic mode since I spend most of my time in manual anyway.

If you are waiting for the focus points to light up when manually focusing, then you are still relying on the AF system. I just skip that step and use AF .

Besides, with the rather small viewfinders on most of DSLR cameras, it's hard to judge precise focus. Especially when you're shooting hand held and your subject is not stationary.

As for how far it's out...it's not by much. But when your DOF is an inch or less thick, a little bit can make or break the shot.

I'm not a fan of autofocus, because I'm not always focusing on what's at the center of the lens. And in order to focus on one specific point, I either have to set which focus point I want to use or turn the center focus point towards my focal point and tell it to AF then move it back. My focal points are often distant objects and/or not in the center of the screen.

Anyway to each his own, I appreciate the responses. The canon 1.4 has alot of negatives reviews about it's AF motor going bad... so I don't know. Anyone else want to weigh in on this?

 

[StudioBin]

I personally like the built quality and warranty terms on the Sigma. I have the Sigma 50 1.4 and a colleague have the Sigma 30 1.4. I would suggest the 30 1.4. Great lens although you should be careful as there are known issues with calibration.

 

[dhilberg]

I was looking into the Sigma 30mm f/1.4, but ended up finding mostly negative reviews of it: Focusing issues, sharpness (lack thereof), heavy vignetting wide open, etc. I'd avoid it. I haven't bought it yet, but I'm looking at the Nikon 35mm f/2.0 instead.

Canon has a 28mm f/1.8 and a 35mm f/2.0 that you might consider if you're not into a 50mm.