85 1.8 vs 135 2 vs 200 2.8

Which of the above lenses will have better lowlight capabilities. Is it only dependent on aperture?

I wouldn't know about the two longer lenses, but the 85 1.8 is really sweet in low light and is not as expensive.

EDIT: Welcome to the forum! Can you give us a shot list of the gear you have because the 20D is much better on low light than the 10D. Depending on the equipment you have, the lens does matter, but the camera is as important.

What focal length do you need?

Basically, the answer to your second question is yes. Low light capability only depends on the maximum aperture.
So an f/1.8 lens is (a bit) faster than an f/2.0 lens that again is faster than an f/2.8 lens.

But ... if you want to increase your reach and add a tele-converter, you will lose 1 or 2 f-stops... so when you get to 135 mm using a t-con on the 85, the 135/2.0 will be faster.

Also ... is the lens sharp when used wide open? I would assume that the 135/2.0 is (a bit) sharper wide open than the 85/1.8.
If you want to have low light capability alone, also take a look at the Canon 50/1.4 and the Sigma 30/1.4 EX (or the $$$ Canon 85/1.2 L)

Best regards,
Andy

Thanks for the replies.

Suzie I have added my sig.

regds
sanil

Ok.
let me be clear. if we consider 85 and 135 lenses-

If I have to get a shoulder head portrait, lets say i have to stand 2 feet away from the subject using 85 mm lens

and if I have to use 135 lens to cover the same area i may have to stand 3 feet away.

In the 135 lens case, since i am standing away dont u think more light can be taken in.
regds
sanil

There is a 1.6 crop on the 350D, so you will stand way farther than 2 feet from your subject with any lens. The 85 will be more than adequate. This lens is described as the perfect portrait lens for children in a small area becaues you don't have to be right on top of them to get close ups. The other lenses are way too long. But if I were you, I'd go to a camera shop near you and try all 3. I can guarantee you will love the 85 1.8 because it is not very expensive, but does a wonderful job. Read the reviews on this lens here on the forum. I think it is the best lens Canon makes for the price.

Hi Sanil,

no, it doesn't work that way. Only the light that hits the front element counts. And it will be exactly the same light rays, if the field of view is identical.

It's even worse ... if you want to handhold the lens, to get images without camera shake, you should use 1/250 seconds on the 135 mm lens (1/135*1.6) versus 1/125 (1/85*1.6) or 1/100 (1/50*1.6) on a 50/1.4 or 50/1.8 lens. (all figures rounded to available camera speeds)

Also, 80 mm (on 35 mm film) is a suggested focal length for portraits, which would correspond to 50 mm on a 1.6x crop body.

Best regards,
Andy

Thanks andy for clarification. I was confused because I have seen better reviews for 135 than for 85 lens for indoor sports conditions. They may not be comparing on lowlight capability alone.

Suzie, i think i will be buying 85 or 135 lens very soon. my sisters marriage is coming up next month and either of these lenses I believe will keep me in good stead.

regards
sanil

Most likely so.

When you attend a sports competition and don't have seats directly at the ring, you'll find yourself craving for more focal length easily.

Other than that, the 135/2.0L lens is one of Canons 'pro' lenses, while the 85/1.8 belongs to their 'standard' lineup ... lots of technical differences that are also reflected in price.

Best regards,
Andy

thanks for the reply andy
anil

Lens advice

sorry - mis-posted

This is not the right way to think. The correct exposure will be the same regardless of whch lens you're using, i.e. the amount of light 'needed' will be the same regardless. A larger aperture will allow you to use a faster shutter speed, assisting to avoind both motion blur and handshake.

Be warned, on the 350D, with the 1.6x crop factor you will probably need to be 6 feet away to get a tight head & shoulders.

I have the 85mm f/1.8, 100mm f/2 and the 135mm f/2L. From personal experience the best of the three taking focus accuracy, focus speed and optics into account is the 100mm f/2.

I agree with things said above.

85 1.8 is a great lens for the money and produces some excellent results

the 135 is quite a bit more expensive but you get what you pay for

I have no experience with the 200 2.8, so I am not sure, but you will need a shutter speed of 250+ to get images sharp in low light (which can be a problem)

WoW!! I guess I'll have to try the 100f2 some time because the I can't believe that it is faster with the AF than the 135L!! On my 1D the 135L is blazingly fast........