Last night I was shooting my grandson's 4th birthday party. Flash photography was decidedly out as the only thing I had with me was the built in flash on my Canon 60D, a 1.6 crop factor camera. That simply made the photos too bright and harsh and negated the decorated theme of dim light and overall ghoulishness (assuming that is even a word).

Knowing I would be working with very dim light, I set my camera on manual with a shutter speed of 1 80th of a second (four year old boys can run pretty fast), aperture at 1.8 on my Canon 50mm prime lens and let the ISO float to 6400 after which the light would be reduced. With fast moving 4 year olds, I decided a tripod would be too slow so I did not take one with me.

Over all the shots were not too bad.....not to good either unfortunately, but many were acceptable.

Inside close quarters the 50mm got a little long with the crop factor so I decided to go to my 24mm prime 2.8. Have not had the 24 very long so I got to compare them side by side in low light. The 24 mm was definitely better in terms of focal length, but many more of these pictures were simply too dark to be worth much......the difference between the 1.8 and the 2.8 obviously.

My question is basically two fold:

First, had I been using a FF camera which I am still considering obtaining, would my aperture have been reduced by the crop factor giving me more effective aperture than I was obtaining with my current crop factor camera??? If so that would be a tremendous gain in terms of low light performance.

Second, from you advanced amateurs and certainly from you professionals, what else could I have done to improve my image quality in this situation based on your own personal experiences? Thank all of you for your input!

(I previously researched this last part of my question on the web and found that there seems to be opinions on this topic that do contradict each other, to say the least....I am confused on this issue but would really like to know as it will impact my decision as to purchasing a FF camera).

Last night I was shooting my grandson's 4th birthday party. Flash photography was decidedly out as the only thing I had with me was the built in flash on my Canon 60D, a 1.6 crop factor camera. That simply made the photos too bright and harsh and negated the decorated theme of dim light and overall ghoulishness (assuming that is even a word).

Knowing I would be working with very dim light, I set my camera on manual with a shutter speed of 1 80th of a second (four year old boys can run pretty fast), aperture at 1.8 on my Canon 50mm prime lens and let the ISO float to 6400 after which the light would be reduced. With fast moving 4 year olds, I decided a tripod would be too slow so I did not take one with me.

Over all the shots were not too bad.....not to good either unfortunately, but many were acceptable.

Inside close quarters the 50mm got a little long with the crop factor so I decided to go to my 24mm prime 2.8. Have not had the 24 very long so I got to compare them side by side in low light. The 24 mm was definitely better in terms of focal length, but many more of these pictures were simply too dark to be worth much......the difference between the 1.8 and the 2.8 obviously.

My question is basically two fold:

First, had I been using a FF camera which I am still considering obtaining, would my aperture have been reduced by the crop factor giving me more effective aperture than I was obtaining with my current crop factor camera??? If so that would be a tremendous gain in terms of low light performance.

Second, from you advanced amateurs and certainly from you professionals, what else could I have done to improve my image quality in this situation based on your own personal experiences? Thank all of you for your input!

(I previously researched this last part of my question on the web and found that there seems to be opinions on this topic that do contradict each other, to say the least....I am confused on this issue but would really like to know as it will impact my decision as to purchasing a FF camera).

Here is a question for you: Have you studied and do you understand the exposure triangle and how it works? [ISO, Shutter Speed, Aperture] Each of these factors affects the others. So adjusting one will in general result in a necessary adjustment of the others in order to get the best balance in the captured image. Sometimes one factor has to be less than optimal in order to achieve a usable photo.

For fast-moving subjects, a fast shutter speed is necessary. This reduces the time for the sensor to capture light. It also helps prevent blur from camera shake when your lens does not have vibration reduction. As a result you must increase aperture and ISO, looking for a balance that will give you sufficient depth of field and better light-gathering ability. If the shutter speed is fast enough and an image still comes out looking blurry, the depth of field may not be enough, or your focus point is not on the subject [so you would be focusing on the foreground or background, or on an arm or leg but not the face].

As you noted, using an FX lens on a DX camera puts the crop factor into play. But the basic principles of exposure still apply in the same way. Switching that FX lens to an FX camera eliminates the crop factor, changing the angle of view, so to get the same composition as on the DX camera, you would have to move in closer. [If using a zoom, you could have stayed in the same place but zoomed in for the same composition. But this has no relationship to what aperture you are using.

The crop vs. FF is a debate that continues! The gap between them is getting smaller as technology improves. This results in making the decision which way to go even more difficult and requires more research to choose between cameras. Most digital cameras have many functions in common, the basis of a choice is in the differences. Comparing specifications this will be clearly seen. Reasons for choosing an FX camera include larger sensor size which suggests better image resolution capability, better low-light ISO performance with less noise at higher values, and a variety of "bells and whistles" that you may or may not ever use. Reasons for choosing a DX camera include lower price point, lighter weight, decent size sensor in newer models, and improved ISO performance [all of this in the newer models]. When I bought my first DSLR in 2012, I could not afford an FX camera, so chose the best of the crop-sensors at the time. It has served me well, and I still keep it as a back-up camera to my D810 purchased last fall.

Hope this helps.
Susan

Your best bet by far in a situation like this? Get a good quality auxiliary flash, a flash bracket and off-camera shoe cord.... and possibly some sort of diffusion panel, bounce card or other light modifier.... and learn to use it!

Wow, you are teaching at the college level and I think I might be in Jr. High, lol. I did understand the jist, I think of most of that. Will look some of that up to better understand. Looks like my next purchase will be that flash........will continue to look for a quality used FF camera too. Will probably keep the 60D for backup/telescopic effect of crop factor, but eventually upgrade to newer generation of crop too................technology tends to cause folks to spend a lot of money, lol.

What some people are not taking into account is what's in the frame. Truth is there isn't any appreciable difference between a Crop & Full Frame camera aperture settings, but what the camera "sees" may affect the aperture the camera selects. Since the cop sensor "sees" a narrower field of view, the settings could be different unless the angle of view is identical between the cameras (meaning the crop sensor camera would need to be farther back to show the same field of view)

Good points Susan. However I more or less consider the real exposure triangle to be Shutter Speed, Aperture and LIGHT. ISO to me is something that can be adjusted in Digital photography but think of it as taking your camera's base ISO and then amplifying the signal that the sensor is collecting and the camera is converting from analog light to a digital number. As the signal is amplified more noise is generated and if the electronic components heat up that heat also can contribute to noise. Long exposures can contribute to noise too. My Canon has a long exposure noise reduction function which can be used if desired.

So, the other option is not just ISO increase but to add Light if you can. And if you are going to add light it is then also good to understand the Inverse Square Law and how that relates to the way light spreads.

Best,
Todd Ferguson