RF 85mm F1.2 L USM - Can I lower my ISO with this lens?

[ranger052]

Hi everyone, I specialize in pet photography and currently shoot with an R6 MK II paired with an RF 70-200 F2.8 lens. I absolutely love this lens; its performance in terms of focus and depth of field is simply amazing. Lately, I've been venturing into capturing more pet photos within small forests, particularly in shaded areas, between the hours of 4 PM and sunset, around 6 PM.

I aim to maintain a minimum shutter speed of 1/500 to ensure sharp images, but I'm facing the challenge of having to substantially increase my ISO, especially when shooting at those sunset hours. My question is, if I were to switch to using the 85mm 1.2 lens, would I still be able to maintain the same 1/500 shutter speed but with a lower ISO? I understand that the 1.2 aperture is designed to allow more light in, but I want to confirm before making the investment. Additionally, with an 85mm lens, I anticipate being able to work more effectively in smaller areas while still achieving a remarkable depth of field without the need for zooming in. Thank you for your insights.

[rs-eos · Accepted solution]

Exposure-wise, yes.  Even at f/1.4, that's 4 times the amount of extra light being gathered or two stops.  So ISO could be lowered say from 6400 down to 1600.

However, be mindful of the shallower depth of field, especially if your subjects will be quite close.  e.g. if you're say 4 feet away, when at 85mm and f/2.8, DOF is 1.28 inches.  Going to f/1.2 reduces that to half an inch.

At 8 feet away, f/2.8 has a DOF of 5.3 inches and f/1.2 a DOF of 2.25 inches.

[rs-eos]

Just to add, when you mention "remarkable depth of field", what specifically do you mean?  A shallow or deep depth of field?  Using wider apertures will lead to shallow DOF.

If you want to shoot in low-light conditions with narrower apertures, start looking at off-camera flash/strobes.  In this case, remember that it will be the flash that is freezing action and not your shutter. So your shutter speed can be set at the flash sync speed (typically around 1/200 s).   Depending upon the lighting you get, you can end up having enough power for even f/16.  Though be mindful if the pulses of light will freak out your subjects.

[wq9nsc]

As Ricky points out, an 85 f1.2 lens is very good at letting a lot of light through to the sensor AND providing an extremely shallow depth of field and those benefits are inseparable.  The extremely shallow depth of field can make an undesirable background fade away to blur but with the lens wide open with a fairly close capture, much of the subject will also fade away to blur.

The attached was shot with my EF 85 f1.2 and 5DS R body, focal point is on Lynx's left eye and this illustrates how shallow a DoF you can create with this lens.

Rodger

[ebiggs1]

I have the EF 85mm f1.2 and I consider it a very specialized and limited use lens. Where it shines it really shines. In other cases not so much.

[ranger052]

Hello everyone! Apologies for the delayed response! Unfortunately, the notification email ended up in my spam folder. Anyway, I stopped by my local store, asked to see the lens, and they kindly allowed me to test it. After taking just two photos, I couldn't resist and ended up purchasing it. I'll test it more thoroughly when I get home, but my initial impressions are outstanding. Thank you all for your detailed answers and explanations! Have a great weekend!

[ranger052]

Guys! I'm speechless about this lens. OMG! The raw photos resemble ones edited in Photoshop. This is the BEST lens I've ever owned, and I can't see myself using the 70-200 anymore, except maybe for pet races. The autofocus isn't as fast as the 70-200, but it's quick enough for capturing pet portraits. Once it locks onto focus, it won't let go. The color rendition is the most natural I've ever seen from a Canon camera. The sharpness? You can see all the details of the dog's face and more, and low light performance is simply AMAZING!

[rs-eos]

Glad you got it all working and are enjoying your new lens.  If there were replies that helped, pick the best one and mark it as the solution.  That will help readers know this topic has been solved.  Thank you.

[ebiggs1]

The fundamental answer to your original question, "Can I lower my ISO with this lens?" the answer is, no. Most folks don't buy the 85mm f1.2 for the fast aperture gain in low light situations but for the application you have noticed. There is an old saying amongst photographers, "There is nothing like f1.2." It is very true and I am sure you are finding that out on your pet projects.